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Abstract

Purpose/Aim: To evaluate the impact of ocular parameters on the visual performance achieved with the multifocal intraocular lens (IOL) Bi-Flex M 677MY. Materials and Methods: 26 subjects were included in the current study. Several physiological variables were retrieved from the 3-month follow-up visit, including pupil diameter and distance from pupil center to the vertex normal of the anterior cornea (µ). These variables were also obtained in the preoperative visit. Binocular and monocular visual acuity defocus curves were measured at 1 and 3 months after surgery, respectively. The area under the monocular defocus curve was computed along the total curve (TAUC, +1.00 to −4.00 D) and for the ranges of far (FAUC, +0.50 to −0.50 D), intermediate (IAUC, - 1.00 to −1.50 D) and near vision (NAUC, −2.00 to −4.00 D). Correlations between these areas and the postoperative physiological variables were assessed. Results: The mean µ was reduced from 0.21 mm to 0.10 mm after surgery, as well as pupil diameters, either photopic (−7.4%) and mesopic (−8.1%) (p < 0.05). The mean AUCs were 2.08 ± 0.74 for TAUC, 0.57 ± 0.17 for FAUC, 0.16 ± 0.09 for IAUC and 0.81 ± 0.29 for NAUC. Significant correlations were found between NAUC and Km (r = −0.39, p = 0.05) as well as between IAUC and temporal decentration of the lens from vertex normal (ρ = −0.41, p = 0.04). Conclusions: The performance at near with the IOL evaluated improved in eyes with less corneal power. On the other hand, a slight temporal IOL decentration from vertex normal also improved intermediate visual acuity. The binocular defocus curve was similar to other trifocal IOLs.

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... 8 Although contrast sensitivity (CS) can decrease for small pupil sizes at far distance, conversely it might be increased at near and intermediate distances. 11 The possible disadvantage of CS decrease for small pupil sizes should be therefore judged considering the possible advantage of incrementing CS at intermediate or near distances. ...
... Procedures to measure variables such as MIOL decentration, chord-mu, and others have been detailed in previous studies. 11,13,14 Statistical analysis Normality of data distributions from variables included in the study was tested with Shapiro-Wilk test. Agreement between postoperative pupil diameters was evaluated by means of computing mean differences and the limits of agreement (LoAs). ...
... As in previous studies, the pupil diameter was found to decrease around 10% after surgery. 11,17 Pupil size measured with a rule at 90 lux of environmental light was closer to the photopic value obtained with Keratograph 5M, and the mean difference was reduced considerably for the average pupil. Average and photopic pupils showed stronger correlations with distance-corrected visual acuities than the pupil size measured with a rule. ...
Article
Purpose: To identify the most sensitive visual performance metric for evaluating the pupil-dependency of a multifocal intraocular lens (MIOL) and to determine the pupil measurement method most correlated with such metric. Methods: Twenty-seven right eyes implanted with a MIOL were included in the analysis. Three pupil size measurements were obtained preoperatively and at 1 month after surgery with the Keratograph 5M system: photopic (PP), mesopic (MP), and the average from both (AP). Pupil was also measured with a rule (RP) under the same light conditions of postoperative visual performance measurements that included, corrected visual acuities (VA) at three distances (far, 67 cm and 40 cm), visual acuity (VADC) and contrast sensitivity defocus curves for optotype sizes of 0.3 logMAR (CSDC3) and 0.7 logMAR (CSDC7). Differences in visual performance were also analyzed for eyes with RP > 3 mm (Group A) and RP ⩽ 3 mm (Group B). Results: PP diameter decreased after surgery by 16% (p = 0.001), whereas MP (p = 0.013) and AP (p = 0.008) decreased by 10%. The best agreement with RP was obtained for AP. Group B showed a trend to better performance than Group A for all the included metrics (p > 0.05). From the three types of defocus curves, CSDC3 obtained generally highest statistical power for testing differences between groups. The strongest statistically significant correlations between pupil size and CSDC3 were obtained for RP and AP. Conclusion: The CSDC3 was the most sensitive metric to detect MIOL pupil-dependency. PR and AP were more correlated with CSDC3 than PP and MP.
... Fu et al. [10] and Piracha [11] found that if the distance of the chord alpha is larger than 0.5 mm, the eye will not be suitable for MIOL implantation. Recently, Fernández et al. [16] have studied how biometric factors could be linked to visual performance in high addition MIOL and found that chord mu was significantly reduced after cataract surgery. Similar results were reported by Wang et al [17]. ...
... Traditionally, it has been emphasized that a larger kappa angle could negatively affect the subsequent satisfaction of patients with MIOL or refractive surgery [12,20,21,32], although this fact is currently under debate [33]. Actually, the kappa angle or chord mu could change after surgery [16,17,34]. Recently, the role of the alpha angle or chord alpha seems to take more importance. ...
... This fact may influence in the amount of both chords. However, although the largest pupil offset could be found in the hyperopic normal patients, recently it was shown that there was also a wide range of pupil offset in myopic and emmetropic eyes [16]. Nevertheless, on the one hand, due to lack of data of some of them-since they were derived from other centers-and in the other hand, because refraction may not be reliable due to preoperative corneal edema status in some of them, we decided not to include the refraction status here. ...
Article
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This paper will evaluate chord mu and alpha length in patients with Fuchs endothelial corneal dystrophy (FECD) and its changes following Descemet membrane endothelial keratoplasty (DMEK). Patients with FECD that underwent DMEK surgery were included in this retrospective study. Scheimpflug Tomography was carried out in order to calculate chord mu and chord alpha lengths prior to surgery and at 3 and 12 months postoperative. This study included 27 eyes from 27 patients. Significant changes in chord mu were observed within the first three months (from 0.47 ± 0.32 to 0.29 ± 0.21 mm, p < 0.01) and remained stable 12 months postoperative (0.30 ± 0.21 mm, p > 0.05). However, chord alpha remained stable throughout the 12 months post surgery (from 0.53 ± 0.19 to 0.49 ± 0.14 mm, p > 0.05). In addition to the pupillary center distance from the corneal apex (from 0.35 ± 0.25 to 0.34 ± 0.20 mm, p > 0.05) also remain stable. In FECD patients undergoing DMEK surgery, chord mu length decreased, and chord alpha length remained stable after 12 months of follow-up.
... Visual outcomes reflect the refractive results. Both IOLs provided sharp vision at multiple distances (far, intermediate, near), and the uncorrected distance, intermediate and near visual acuities are in good agreement with previously published data for these lenses [21][22][23][24][25][26][27][28]. Nevertheless, a remarkably higher proportion of eyes achieved good functional monocular vision at multiple distances with the Liberty lens compared to the plate-haptic AT LISA tri. ...
... Furthermore, the visual function assessment results of the two examined lenses are also comparable-not only in the intermediate range but also for near and far distances. The near vision range provided by the Liberty IOL in our study (from about −1.75 D to −3.5 D defocus) was wider than that of the AT LISA tri and similar to that previously reported by Fernández et al. [24]. This difference may explain the higher percentage of Liberty patients achieving spectacle independence for near vision compared to the AT LISA tri group (100% vs. 92.9%). ...
... Because AXL was similar in the two IOL groups in our study (p = 0.6400), we believe that the differences between groups in the refractive and visual outcomes are not attributable to this anatomical parameter. IOL decentration and tilt were not measured in our study, although both the Liberty and AT LISA tri IOLs have been reported to undergo some decentration following implantation [24,39]. IOL decentration can affect refractive and visual outcomes [38,40]. ...
Article
Full-text available
This semi-prospective, parallel, comparative investigation evaluated the clinical outcomes and quality of vision (contrast sensitivity, visual function, dysphotopsia, spectacle use, overall satisfaction) after mono- or bilateral implantation of two presbyopia-correcting intraocular lenses (IOL)—the Liberty® 677MY or the AT LISA® tri 839M—in 50 eyes of 25 cataract patients. Clinical outcomes were assessed 3 and 12 months postoperatively. Eighty-nine percent of eyes implanted with the Liberty IOL and 59% of eyes implanted with the AT LISA IOL achieved a refractive outcome ±0.5 diopters of the target (emmetropia). Refractive outcomes were stable with both lenses. The proportions of eyes with 20/20 uncorrected distance visual acuity (UDVA) and 20/20 uncorrected near visual acuity (UNVA) were higher in the Liberty group than in the AT LISA group (UDVA: 56% vs. 41%; UNVA: 83% vs. 66%). Optical quality assessment results were comparable for the two IOLs. Superior photopic contrast sensitivity was found with the Liberty lens. The rate of Nd:YAG capsulotomy at the 12-month follow-up was 16.7% in the Liberty group and 40.6% for the AT LISA IOL. Considering that both lenses are made from the same material, we propose that the noted differences in clinical outcomes may derive from differences in design and optical surface between the two IOLs.
... of the spherical aberration corresponding to the mesopic pupil size. 15 Another example is the drawback of halo size increasing with the pupil diameter due to the parasitic near focus when patients are looking at far distance, which has been demonstrated in optical bench studies, 16 but there is a lack of clinical evidence to date. 17 It could probably be explained by the constriction of pupil size, reaching a different diameter than that corresponding to mesopic conditions, due to the glare source during the measurement. ...
... The optical design of these multifocal IOLs has been previously described. 15,18,19 Exclusion criteria were those applicable to any multifocal IOL implantation according to standard clinical practice, including: ocular pathology that could decrease visual acuity (eg, corneal diseases, uveitis, retinopathy, glaucoma, dry eye, or amblyopia) or irregular astigmatism higher than 0.5 µm measured with Pentacam HR (Oculus Optikgeräte GmbH) at 4 mm. 20 Photopic and mesopic pupil sizes measured with the Keratograph 5M (Oculus Optikgeräte GmbH) were included in the analysis and the average from both was also calculated (average pupil size). ...
... 8 Only postoperative measurements of pupil diameter were included in this study because the aim was to evaluate the distribution of pupil size in patients already implanted with multifocal IOLs. The change in pupil diameter after surgery was not included in the analysis because it was already covered in previous studies by our research group, 15,22 with conclusions in agreement with other authors. 15,22,[24][25][26] Studies have reported a statistically significant reduction of the pupil diameter at 3 days postoperatively. ...
Article
PURPOSE: To evaluate the distribution of pupil size in patients implanted with multifocal intraocular lenses (IOLs) and to assess the variations according to age. METHODS: A total of 168 eyes that had implantation of several multifocal IOLs and were measured at the 3-month follow-up visit were included in the analysis. The Keratograph 5M (Oculus Optikgeräte) was used to measure the photopic and mesopic pupil size, as well as the average between both (average pupil size). Eyes were stratified in four groups by age: 50 years or younger, 51 to 60 years, 61 to 70 years, and older than 70 years. RESULTS: Considering the total sample, 84.5% and 95.8% of eyes had a photopic pupil size of 3 and 3.5 mm or less, respectively. The mesopic pupil size was greater than 4.5 mm in 39.3% and greater than 5 mm in 16.7% of eyes. The average pupil size was 3.5 and 4 mm or less in 54.2% and 85.1% of eyes, respectively. Mesopic pupil size resulted in a steeper decrease with age than photopic pupil size: 0.028 versus 0.015 mm/year, respectively. Statistically significant differences were found among the four age groups (P < .0005). No significant mean differences were found between multifocal IOL models for photopic pupil size, mesopic pupil size, or average pupil size (P > .05). CONCLUSIONS: Eyes implanted with multifocal IOLs had a photopic pupil size of 3.5 mm or less and mesopic pupil size of 5 mm or less. Mesopic and photopic pupil size decreased 0.28 and 0.15 mm per decade, respectively. This information can help surgeons to understand the general functioning of multifocal IOLs whose performance varies with pupil size.
... 5 However, the expectations at intermediate vision with bifocal MIOLs were not covered for some patients, and this led to a reduction of the addition, 6 to mix-and-match procedures, 7 and to the emergence of the most implanted category, trifocal MIOLs. 8 Trifocal MIOLs are commonly characterized by focusing the light of intermediate focus at half of the addition of near focus, these trifocal MIOLs provide an effective intermediate vision between ~90 cm to ~99 cm (distance depending on corneal power, effective lens position and IOL power), 9,10 moving away the intermediate vision distance as the near addition decrease from 3.5 D to 3.0 D (i.e. AT Lisa tri 839 from Carl Zeiss Meditec AG & FineVision from PhysIOL S.A.). ...
... Unlike previous designs, this new design modified the location of the intermediate focus at 2/3 the near addition, thus approaching the intermediate focus up to ~70 cm without requiring to increase the addition. 9,10 The main aim of this study was to assess, following the standards, 11 the results of safety, efficacy and predictability for this new MIOL. The secondary aim was to evaluate contrast sensitivity at several conditions and visual acuity defocus curve. ...
... The reason why some authors conducted the intermediate measurement at 60 cm was to maximize VA results at this distance since Carson et al. 27 reported the intermediate focus at 60 cm. However, according to our calculations and in agreement with Savini et al., 9,10 the reported values of Carson et al. 27 might underestimate the distances for all the tested IOLs and the PanOptix IOL really has the maximum intermediate enhancement at ~67 cm and not ~60 cm as many authors have reported. 13,18,19,23,25,28 In fact, the maximum peak at near for binocular defocus curves in our study was at 50 cm (−2.0 D), in agreement with previous studies, 13,18,21,23,24 which corresponds to an underestimation of the near best distance of 42 cm reported by Carson et al. 27 About predictability, we used the Barrett Universal II formula and we achieved a 90% of eyes in ±0.5 D, higher than the 80% reported by Shajari et al. 25 or the 76% by Cochener et al. 24 and closer to the 88% by Rodov et al. 26 or the 94.8% by García-Pérez et al. 23 However, comparisons about predictability from several studies should be interpreted with caution because differences can be explained by the characteristics of the sample or by using different formulas sometimes even in the same study. ...
Article
Purpose/Aim to assess, following the standards, the results of safety, efficacy and predictability for a trifocal intraocular lens and to evaluate contrast sensitivity and visual acuity defocus curve. Materials and Methods 50 subjects operated on cataract surgery or refractive lens exchange with a trifocal intraocular lens have been recruited for the study. The monocular uncorrected visual acuity (VA) at far, intermediate (67 cm) and near (40 cm) distances in addition to corrected VA at far and near distances was evaluated at 1 week, 1 month and 3 months after surgery. Postoperative refraction, binocular contrast sensitivity function (CSF) and binocular defocus curves were also collected at the 3 months follow-up visit. Results Mean uncorrected VA was 0.10, 0.07 and 0.05 logMAR at far, intermediate and near distances. Corrected distance VA at far and near distances was 0.04 and 0.02 logMAR. 90% and 100% achieved a spherical equivalent in ±0.50 D and ±1.00 D, respectively. CSF was above normal range for 12 and 18 cycles per degree (cpd) in all the conditions, inside the normal range in 1.5, 3 and 6 cpd and only decreased below normal range for 1.5 and 3 cpd in mesopic vision without glare. Conclusions The procedure achieved a safety, efficacy and predictability similar to those reported by previous studies. The CSF was generally enhanced after the procedure in comparison to those reported in non-operated subjects above 60 years old. Previous studies might underestimate the effective distance of the intermediate and near foci.
... Visual acuities measured 1 and 3 months postoperatively were similar, although a slight improvement of distance vision could be observed. This might be due to the modification of the ocular inner geometry after IOL implantation [31], neuroadaptation processes [32], or a slight decentration of the IOL, which was previously reported on the Liberty 677MY lens [17]. An important limitation of our current study is that exact measurements of IOL decentration were not performed, and therefore, its contribution to visual outcomes could not be assessed. ...
... An important limitation of our current study is that exact measurements of IOL decentration were not performed, and therefore, its contribution to visual outcomes could not be assessed. Nevertheless, our visual acuity results are in good agreement with the measurements reported by other papers, following the implantation of the same MIOL [17,33]. ...
... Both curves confirm good quality vision along all of the defocus range, which is further confirmed by the complete spectacle independence achieved by the majority of the patients. Our VADCs are similar to those reported in previous studies after the implantation of the same presbyopia-correcting IOL [17,28]. We found it important to plot the visual acuity, in addition to contrast sensitivity defocus curves, as these curves are more sensitive to small changes in optical quality than VA [28,34]. ...
Article
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The aim of our investigation was to examine the possible correlations between optical aberrations, angle kappa, angle alpha, and visual outcomes following cataract surgery. In total, 56 eyes of 28 patients were implanted with the Liberty 677MY trifocal intraocular lens (IOL). Pre- and postoperative higher-order aberrations, coma, astigmatism, angle alpha, and angle kappa were registered, along with uncorrected and corrected visual acuities at multiple distances. Visual acuity and contrast sensitivity defocus curves were plotted, and the areas under the curve were calculated 1 and 3 months postoperatively. Excellent visual outcomes were found at all distances. Patients reported low levels of dysphotopsia, and 96.4% of patients achieved complete spectacle independence. While angle kappa significantly decreased during cataract surgery (p = 0.0007), angle alpha remained unchanged (p = 0.5158). Angle alpha correlated with postoperative HOAs and had a negative impact on near vision (p = 0.0543). Preoperative corneal HOA and coma had a strong adverse effect on future intermediate and near vision. Residual astigmatism significantly affected postoperative intermediate vision (p = 0.0091). Our results suggest that angle kappa is not an optimal predictive factor for future visual outcomes, while angle alpha and the preoperative screening of optical aberrations might help patient selection prior to multifocal IOL implantation.
... 6 The Multifocal Lens Analyzer app 4 has been used to study performance of multifocal IOL. 16 This application has been developed to present calibrated optotypes at a distance of 2 m, it is therefore necessary to optically compensate this distance, taking the optical vergence of 2 m to infinity, by interposing a + 0.50 D lens before starting the scan and the defocus curve. 6,16 This fact could help to control proximal myosis due to the induced convergence when the patient focuses at close distances such as 30 or 40 cms. ...
... 16 This application has been developed to present calibrated optotypes at a distance of 2 m, it is therefore necessary to optically compensate this distance, taking the optical vergence of 2 m to infinity, by interposing a + 0.50 D lens before starting the scan and the defocus curve. 6,16 This fact could help to control proximal myosis due to the induced convergence when the patient focuses at close distances such as 30 or 40 cms. However, despite this fact, the optical behavior of the IOLs is different depending on the addition of each lens, so the influence of the pupil diameter is not decisive in the near vision in this case. ...
Article
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Purpose: To characterize the optical performance of two models of refractive bifocal intraocular lenses, with medium and high addition, using defocus curves. Methods: 20 eyes from 20 subjects were included in this study. 10 eyes underwent caratact surgery with an implant of a medium addition refractive bifocal intraocular lens (IOL) (Lentis LS-313 MF20) and the other 10 eyes underwent cataract surgery with an implant of a high addition refractive bifocal IOL (Lentis LS-313 MF30). Six weeks after surgery, subjective refraction and defocus curve were made. Results: Mean final residual refraction in spherical equivalent was +0.10±0.07D in the LS-313MF30 group and +0.12±0.10D in the LS-313MF20 group. Defocus curve showed a different optical performance in intermediate/near distance depending on the IOL model. The medium addition IOL provided good visual acuity (VA) at far and intermediate distance up to 50cms, and the high addition IOL provided better VA in near distance up to 25cms. Conclusions: The high addition intraocular lens provides better visual acuity in the spatial range from infinity to the point close to 25cm. The medium addition intraocular lens provides excellent visual acuity in far and intermediate vision. The defocus curve seems to be a valid and reproducible tool for evaluating the optical behavior of multifocal sector refractive lenses.
... This finding is in agreement with a previous study with a high addition trifocal intraocular lens, but the increase of performance was presented at the intermediate vision. 21 Therefore, this slight decentration appears to favor the foci with lower energy, either near in a low addition trifocal lens and intermediate in a high addition trifocal lens. However, these results should be interpreted with caution as it is well known that visual acuity is not a good descriptor of visual quality. ...
... The corneal power was the most important factor for predicting the visual acuity along the total curve, this finding is in agreement with a previous study with other high addition trifocal lens. 21 The spherical aberration can show a false relationship with the variation of visual acuity because eyes with lower corneal power have also greater spherical aberration, which means that spherical aberration acts as a confounding variable. Likewise, irregular astigmatism should be considered for the prediction of the near vision with the trifocal IOL evaluated, even for values lower than 0.3 m, because lower irregular astigmatism is related to better near vision. ...
Article
Full-text available
Purpose: To assess the impact of ocular biometric variables on the visual performance achieved with a low addition trifocal intraocular lens (MIOL). Methods: Retrospective observational study including 34 eyes. Preoperative measured variables included mean corneal power (Km), corneal regular astigmatism (RA), anterior chamber depth (ACD), axial length (AXL), total irregular astigmatism (IA), spherical aberration (SA) and distance from pupil center to vertex normal (µ). Same variables were retrieved from the three month visit follow-up in addition to the actual lens position (ALP), the calculated effective addition (EA), the IOL centration from vertex normal (d), and the visual acuity defocus curve. The area under the defocus curve was computed along the total curve (TAUC) and ranges for far (FAUC), intermediate (IAUC) and near vision (NAUC). The sample was split in two groups of 17 eyes with TAUCs above and below the mean, and the differences among groups for different ocular parameters were assessed. Results: The group of eyes above TAUC of 2.03 logMAR*m-1 showed significantly lower Km and greater AXL and SA. Km was negatively correlated with TAUC and NAUC. NAUC was negatively correlated with IA and positively with d. A multiple lineal regression model including Km, d, and IA predicted NAUC (r-square = 34%). No significant differences between IA and SA were found between preoperative and postoperative values but µ significantly decreased after surgery. Conclusions: The mean corneal power, irregular astigmatism, and centration from vertex normal should be considered for optimizing the near visual performance with this MIOL.
... This was consistent with the high levels of refractive predictability achieved, with almost all eyes (99%) having a postoperative spherical equivalent within ±0.50 D. These results were consistent with or even better than those reported with other models of multifocal IOLs. [12][13][14][15][16][17][18][19] Likewise, the UDVA and CDVA outcomes obtained were also similar to those found with EDOF IOLs, confirming the excellent optical performance of this new presbyopia-correcting IOL for distance foci. 12,17,19,20 Manifest residual cylinders of 0.50 D or greater were found to have a significant impact on distance visual outcomes. ...
... This contrast with the defocus curves was reported for most presbyopia-correcting IOLs (especially bifocals), which showed a more or less relevant decrease of visual acuity in the intermediate defocus range. [12][13][14][15][16][17][18][19][20][25][26][27][28] This continuous range of focus may be the main reason explaining the great subjective improvement reported by the patient as evaluated with the Catquest-9SF questionnaire. Indeed, the improvement observed in the Rasch calibrated scoring of item 2 and the Rasch calibrated mean score in our series was higher than that observed in previous studies evaluating the PROMs after cataract surgery with implantation of monofocal IOLs. ...
Article
Purpose: To evaluate the clinical outcomes including patient-reported outcome measures in a sample of eyes undergoing bilateral cataract surgery with implantation of a new model of presbyopia-correcting intraocular lens (IOL). Methods: This non-randomized prospective case series enrolled 206 eyes of 103 patients undergoing phacoemulsification cataract surgery with bilateral implantation of the TECNIS Synergy IOL (Johnson & Johnson Vision). High and low contrast visual acuity, refractive, defocus curve, and patient-reported visual performance (Catquest-9SF questionnaire) outcomes were evaluated during a 3-month follow-up. Results: A total of 96.1% (99 of 103) and 91.3% (94 of 103) of patients achieved binocular postoperative uncorrected distance (UDVA) and near visual acuity (UNVA) of 0.00 logMAR (20/20), respectively. Mean postoperative mesopic UNVA for both eyes was 0.14 ± 0.03 logMAR. Likewise, mean binocular UDVA and UNVA were 0.00 ± 0.03 and 0.04 ± 0.02 logMAR. An almost flat mean defocus curve was obtained, with visual acuities between 0.00 and 0.10 logMAR for most defocus levels in both eyes. A reduction of contrast led to a limited but statistically significant change in UNVA in both eyes (P < .001). The Rasch calibrated scoring of item 2 and the Rasch calibrated mean score of the Catquest-9SF questionnaire increased significantly with surgery (P < .001). Conclusions: This new presbyopia-correcting IOL provides a continuous range of functional focus, with a limited deterioration under mesopic conditions, which is perceived as a satisfactory outcome by the patient if proper patient selection is performed. [J Refract Surg. 2021;37(4):256-262.].
... 10,11,14,15 According to the manufacturer, the 1stQ AddOn diffractive supplementary IOL has an optic similar to the Medicontur Liberty ® 677MY capsular bag IOL, with clinical trifocal performance and spectacle independence of patients being confirmed in related studies. [16][17][18] ...
... The defocus curves of the add-on lens were found to be similar to those of the Liberty trifocal capsular bag IOL made by the same manufacturer. [16][17][18] In this study, we also compared the defocus curves of the supplementary IOL to a subset of patients previously implanted with a primary capsular bag trifocal IOL, which is considered the "gold standard" for trifocal lenses. We found that the add-on lens provided better visual acuities in the intermediate (−1.5 to −2.0 D) and near (−3.5 D and −4.0 D addition) ranges of vision. ...
Article
Full-text available
Purpose: To evaluate the refractive and functional outcomes of the trifocal 1stQ AddOn® (Medicontur) supplementary intraocular lenses (IOLs) designed for implantation into the ciliary sulcus. Patients and methods: The study included 18 eyes of 11 pseudophakic patients with uncomplicated previous implantation of monofocal capsular bag IOLs. These patients had a desire for spectacle independence. Distance, intermediate and near visual acuities were measured, and defocus curves were plotted over a period of 6 months following implantation of the add-on IOLs. Intraocular pressure (IOP), endothelial cell density measurements and biomicroscopic evaluation were also performed. Results: In this study, 83.3% of eyes had spherical refractions within ±0.5 D from emetropia and 100% of eyes had spherical equivalent refractions that were within ±1.0 D of the target refraction. Visual acuities and defocus curves clearly confirmed trifocal optical performance (UDVA=0.03 ±0.05; UIVA=0.21 ±0.04; UNVA=0.12 ±0.04 logMAR; expressed as mean ±SD). Depth of focus showed identical results (DOF=0.486 D) compared to a trifocal capsular bag IOL, while the defocus curve was found to be superior in the intermediate and near ranges when compared to a trifocal capsular bag IOL. All patients achieved spectacle independence at all distances. All add-on IOLs were well positioned in the ciliary sulcus. No negative changes were noted in connection with endothelial cell counts, IOPs, the angle structure during surgery and during the follow-up period. Conclusion: The supplementary trifocal add-on IOL seems to be a safe, efficient and stable solution for achieving spectacle independence in pseudophakic patients with monofocal primary IOLs.
... In addition, new metrics can be derived in real time such as the area under the defocus curve, which so far was only possible with complex analysis difficult to implement for the clinician [32]. This new metric can help to predict the visual performance before surgery based on biometric eye characteristics as we have recently demonstrated [35]. ...
Article
Full-text available
Objective To evaluate the repeatability of the fast measurement of the visual acuity (VADC) and contrast sensitivity (CSDC) defocus curves with a new test as well as the agreement of measurements at far distance obtained with the Early Treatment Diabetic Retinopathy Study (ETDRS) chart and the ClinicCSF test for measuring Contrast Sensitivity Function (CSF). Method Records from fifty-nine subjects implanted with Multifocal Intraocular Lenses (MIOLs) were retrieved from our database. VADC and CSDC were measured from +1.00 D to -4.00 D in 0.50 D steps. The agreement with the ETDRS and the CSF at far distance was assessed in comparison to the 0 D location of the VADC and the CSDC, respectively. The repeatability was evaluated in 34 subjects who consecutively repeated two measures. Results Median Visual Acuity (VA) was -0.1 logMAR with the VADC at 0 D of defocus and 0 logMAR with the ETDRS (p>0.05). A total of 45.8% of eyes showed no differences between both tests and the difference was less than one line of VA in 96.6% of the eyes. The intrasubject repeatability was under one line of VA along all the defocus curve except for positive defocus levels. The CSDC showed the best agreement with the CSF for 18 cycles per degree. The CSDC was less repeatable than VADC. Mean time spent on completing the VADC and CSDC was 7.81 and 7.98 minutes, respectively. Conclusion The VADC showed good agreement with the ETDRS and good repeatability despite the short testing time. In contrast, poorer repeatability was found for CSDC. Our method would facilitate the inclusion of VADC in clinical practice as it is a fast test, being also the first one including the measure of CSDC.
... I nterest in the prediction of the postoperative visual performance before the implantation of a multifocal intraocular lens (IOL) has increased in recent years. 1 For individual predictions, new devices have emerged with the aim of simulating how the patient would see after surgery with the implantation of a multifocal IOL. [2][3][4][5][6] However, the main drawback of these technologies is that they would underestimate the postoperative visual performance with increasing age, especially after 50 years of age. ...
Article
Purpose: To evaluate whether the prediction of visual performance based on the modulation transfer function area (MTFa) calculated with optical simulations is better correlated with visual acuity or contrast sensitivity obtained from defocus curves in patients implanted with a trifocal intraocular lens. Methods: Biometric eye data from 43 patients were used to create a mean eye model. A trifocal intraocular lens with a power obtained from the mean of the eyes implanted was incorporated into the model and the MTFa was calculated at the 11 defocus planes corresponding the 11 defocus locations measured in clinical practice. Simulations were conducted for pupil diameters of 2.5, 3, 3.5, and 4 mm. The MTFa correlation with visual acuity and contrast sensitivity was evaluated with the mean obtained after stratification of the clinical sample in four groups according to the previous pupil diameters. Results: A linear model predicted the visual acuity and contrast sensitivity from MTFa with similar accuracy to nonlinear models, with R2 approximately 0.50 for visual acuity and approximately 0.42 for contrast sensitivity. A change of -0.01 logMAR and -0.02 logC was produced per unit of MTFa for visual acuity and contrast sensitivity, respectively. The mean difference between the visual acuity and contrast sensitivity obtained from the model and that measured in clinical practice was close to zero, but the bias varied depending on the defocus lens used, with higher deviation at -0.50 and -3.00 diopters of defocus. Conclusions: The MTFa obtained from optical simulations can be used to predict the mean visual acuity and contrast sensitivity consistently, with contrast sensitivity being more sensitive but with higher bias. [J Refract Surg. 2019;35(12):789-795.].
... Therefore, it was concluded that a slight decentration of such lenses may be recommendable to achieve better visual acuity at near. The same group evaluated visual performance in the presence of a decentred high-addition diffractive multifocal IOL (Bi-Flex M 677MY, Medicontur Medical Engineering Ltd. Inc., Zsámbék, Hungary) [47]. It was revealed that intermediate vision in terms of IAUC (intermediate area under curve) increases with a temporal decentration of less than 0.55 mm. ...
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Tilt and decentration of intraocular lenses (IOL) may occur secondary to a complicated cataract surgery or following an uneventful phacoemulsification. Although up to 2-3 • tilt and a 0.2-0.3 mm decentration are common and clinically unnoticed for any design of IOL, larger extent of tilt and decentration has a negative impact on the optical performance and subsequently, the patients' satisfaction. This negative impact does not affect various types of IOLs equally. In this paper we review the methods of measuring IOL tilt and decentration and focus on the effect of IOL tilt and decentration on visual function, in particular visual acuity, dysphotopsia, and wavefront aberrations. Our review found that the methods to measure the IOL displacement have significantly evolved and the available studies have employed different methods in their measurement, while comparability of these methods is questionable. There has been no universal reference point and axis to measure the IOL displacement between different studies. A remarkably high variety and brands of IOLs are used in various studies and occasionally, opposite results are noticed when two different brands of a same design were compared against another IOL design in two studies. We conclude that <5 • of inferotemporal tilt is common in both crystalline lenses and IOLs with a correlation between pre-and postoperative lens tilt. IOL tilt has been noticed more frequently with scleral fixated compared with in-the-bag IOLs. IOL decentration has a greater impact than tilt on reduction of visual acuity. There was no correlation between IOL tilt and decentration and dysphotopsia. The advantages of aspheric IOLs are lost when decentration is >0.5 mm. The effect of IOL displacement on visual function is more pronounced in aberration correcting IOLs compared to spherical and standard non-aberration correcting aspherical IOLs and in multifocal versus monofocal IOLs. Internal coma has been frequently associated with IOL tilt and decentration, and this increases with pupil size. There is no correlation between spherical aberration and IOL tilt or decentration. Although IOL tilt produces significant impact on visual outcome in toric IOLs, these lenses are more sensitive to rotation compared to tilt.
... The same iPad was used to measure the contrast sensitivity defocus curve (CSDC) with a Multifocal Lens Analyzer (3.0; Snellen letters; https://www.defocuscurve.com/en/; Accessed 5 May 2021) [19,20]. Defocus lenses from +1.00 D to −4.00 D, in steps of +0.50 D, were selected for measuring CSDC at 4 m in the randomly selected eye, with a best distance spectacle refraction and vergence distance correction of +0.25 D. The Light Distortion Analyzer (CEORLab, University of Minho, Braga, Portugal) was used to measure the photic phenomena monocularly, with the best distance correction in the eye randomly selected and binocularly without correction 2 m from the observer (proximal vergence corrected with +0.50 D). ...
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1) Background: To evaluate the efficacy at 6 years postoperative after the implantation of a trifocal intraocular lens (IOL) AT Lisa Tri 839MP. The secondary objective was to evaluate the contrast sensitivity defocus curve (CSDC), light distortion analysis (LDA), and patient reported outcomes (PROs). (2) Methods: Sixty-two subjects participated in phone call interviews to collect data regarding a visual function questionnaire (VF-14), a patient reported spectacle independence questionnaire (PRSIQ), and questions related to satisfaction and decision to be implanted with the same IOL. Thirty-seven of these subjects were consecutively invited to a study visit for measurement of their visual acuity (VA), CSDC, and LDA. (3) Results: The mean monocular distance corrected VA was −0.05, 0.08, and 0.05 logMAR at far and distances of 67 cm and 40 cm, respectively. These VAs were significantly superior to those reported in previous literature (p < 0.05). The total area under the CSDC was 2.29 logCS/m −1 and the light distortion index 18.82%. The mean VF-14 score was 94.73, with 19.4% of subjects requiring spectacles occasionally for near distances, and 88.9% considering the decision of being operated again; (4) Conclusions: Long-term AT LISA Tri 839MP IOL efficacy results were equal or better than those reported 12 months postoperatively in previous studies. The spectacle independence and satisfaction rates were comparable to those reported in short-term studies.
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Purpose To evaluate the visual quality, visual performance, and patient satisfaction after the implantation of the last generation supplementary intraocular lens (1stQ AddOn Trifocal) for achieving near vision spectacle-independence in pseudophakic patients who had primary monofocal capsular bag implantation. Methods Patients who underwent monofocal lens surgery in the past year, and who expressed their explicit desire to become spectacle-independent were included in this prospective observational study. Uncorrected and corrected distance, intermediate and near visual acuities (CDVA, UDVA, DCIVA, UIVA, CNVA, and UNVA), refractive outcomes, lens positioning, contrast sensitivity and patient satisfaction were assessed 6 months postoperatively. Results About 28 eyes of 18 patients were evaluated. No intra- or postoperative complications (iris chafing, iris capture, interlenticular opacification, IOL-dislocation, etc.) could be observed. The postoperative mean UDVA and CDVA were 0.05 ± 0.08 and 0.01 ± 0.03 (logMAR), respectively. The mean UNVA improved from the preoperative 0.50 ± 0.23 to 0.02 ± 0.05 (logMAR), postoperatively ( p = 0.0104). The postoperative mean UIVA and DCIVA were 0.06 ± 0.020 and 0.01 ± 0.00 (logMAR), respectively. Twenty-five eyes (89%) had a residual spherical equivalent within 1.0 D from the target refraction, emmetropia. Contrast sensitivity measured in photopic and mesopic conditions were statistically indifferent from the preoperative curves. All patients had better visual function and quality scores compared to the preoperative responses. The highest improvement could be achieved in near vision activities, dependency, and limitation of social functioning. Conclusion The 1stQ AddOn Trifocal lens represents a safe and effective option for pseudophakic patients aiming for high quality, spectacle-free vision.
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Purpose To evaluate the changes in pupil diameter in women and men after cataract surgery. The correlation of pupillary changes with the variables age and anterior chamber depth will be analyzed. Methods The values of 109 randomized eyes who underwent cataract surgery were obtained and divided into two groups, 71 women and 38 men. Pupil diameter was measured preoperatively and 3-months postoperatively using the pupillometer software of the Topolyzer Vario (Wavelight Laser Technologie AG). Anterior chamber depth was obtained with Pentacam® (Oculus). Differences in pupillary diameters were investigated and correlations with age and anterior chamber depth were analyzed. Results For mesopic pupils, the male group had greater reduction in their postoperative pupillary diameter, −0.56 mm (−12.4%), than the female group, −0.38 mm (−8.2%), P = 0.025. Photopic postoperative pupils reduced to a lesser extent, yet more in men than in women (−0.11mm [−4.5%] vs. −0.04 [−1.6%], P = 0.048). Weak significant negative correlation was found between photopic pupillary changes in women with age (r = −0.24, P = 0.041), and positive correlation for mesopic pupillary changes in men with age (r = +0.34, P = 0.039). Conclusions Patients experience pupil reduction after cataract surgery in general, but more in men than in women and for both photopic and mesopic lighting conditions. The differences are statistically significant and have moderate clinical relevance. Concerning pupillary changes, weak but opposite sign correlations were found between male/female gender and age. Trial registration number at ClinicalTrials.gov Identifier: NCT04286646.
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Purpose To compare the visual and refractive outcomes obtained with the implantation of a rotationally asymmetric refractive multifocal IOL after femtosecond laser-assisted cataract surgery (FLACS) and conventional lens extraction (CLE). Methods A total of 78 eyes of 58 patients that had undergone conventional phacoemulsification (36 eyes, CLE group) or FLACS (37 eyes, FLACS group) with the implantation of the toric multifocal IOL LU-313 MF30T (Oculentis, Germany) were enrolled in this retrospective study. Mean age was 57.0 years at the time of surgery, ranging from 44 to 69 years. Visual and refractive outcomes were evaluated during a 12-month follow-up. Likewise, contrast sensitivity was assessed at the end of the follow-up. Results Significant improvements were observed in both groups in uncorrected distance (UDVA) and near visual acuity (UNVA) at 1 month postoperatively (p < 0.001). Differences between groups in these parameters as well as in sphere and cylinder did not reach statistical significance during the whole follow-up (p ≥ 0.079), except for UNVA only at 12 months postoperatively (p = 0.018). Concerning corrected near visual acuity, only significant differences between groups were found preoperatively (p = 0.020). Furthermore, only a minimal but significant difference between groups was found at 12 months postoperatively in contrast sensitivity for the spatial frequency of 18 cycles/° (p = 0.029). Conclusions The rotationally asymmetric toric multifocal IOL LU-313 MF 30T provides good visual rehabilitation for near and distance vision after presbyopic lens extraction in eyes with preexisting astigmatism, independently whether the cataract surgery is performed with the FLACS or conventional technique.
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Purpose: To compare the optical performance and quality of life after implantation of a new progressively apodized diffractive multifocal intraocular lens (IOL) and report the visual and patient-reported outcomes and contrast sensitivity. Setting: Csolnoky Ferenc Hospital, Veszprem, Hungary. Design: Prospective case series. Methods: Patients had bilateral implantation of the trifocal IOL during cataract surgery. The preoperative corrected distance visual acuity (CDVA) and postoperative uncorrected distance visual acuity (UDVA), CDVA, uncorrected (UIVA) and corrected (CIVA) intermediate visual acuities, and uncorrected (UNVA) and corrected (CNVA) near visual acuities (all logarithm of the minimum angle of resolution) were collected. Contrast sensitivity, slitlamp photographs for evaluation of posterior capsule opacification, and a quality-of-vision questionnaire were assessed. Results: The study comprised 100 eyes (50 patients). The mean postoperative UDVA was 0.01 at 3, 6, 12, and 24 months. The mean CDVA was -0.02 ± 0.03 (SD) at 6 months, -0.04 ± 0.05 at 1 year, and 0.06 ± 0.05 at 2 years. The mean UIVA was 0.05 ± 0.11, 0.04 ± 0.09, and 0.06 ± 0.11, respectively. The mean CIVA was -0.01 ± 0.07, -0.02 ± 0.06, and -0.01 ± 0.07, respectively. The mean UNVA was 0.08 ± 0.08, 0.07 ± 0.08, and 0.10 ± 0.09, respectively. The mean CNVA was 0.03 ± 0.06 at 3 months, 0.04 ± 0.05 at 1 year, and 0.05 ± 0.07 at 2 years. The mesopic and photopic contrast sensitivity values were within the upper normal range for age-matched values. Conclusions: Bilateral implantation of a new trifocal IOL with centralized diffractive rings provided good functional vision at all distances. The levels of spectacle independence and patient satisfaction were high with minimal dysphotopsia symtoms.
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Purpose: To evaluate the standard clinical outcomes, defocus curves, and satisfaction obtained with a new diffractive low addition trifocal intraocular lens (IOL). Methods: Thirty patients who were implanted with the Versario Multifocal 3F IOL (Valeant Med Sp.zo.o., Warsaw, Poland) were recruited for a prospective observational study at Qvision, Vithas Virgen del Mar Hospital, Almería, Spain. Variables for reporting standard outcomes were collected at the 1-month visit for monocular vision and the 3-month visit for binocular vision, including best spectacle refraction and corrected and uncorrected visual acuities at far, intermediate (67 cm), and near (40 cm) distances. In addition, monocular and binocular visual acuity defocus curves were measured and questionnaires for grading subjective visual quality, satisfaction, and visual function were supplied at the end of the follow-up. Results: Monocular corrected distance visual acuity decreased progressively from far (-0.05 logMAR) to near (0.25 logMAR) and improved approximately -0.1 logMAR along the defocus curve in binocular vision. The mean residual spherical equivalent (SE) was 0.15 ± 0.47 diopters (D), with 79% of eyes within ±0.50 D and 97% within ±1.00 D with the SRK/T formula. All of the visual function tasks improved after surgery, especially driving at night, which increased from 58 to 79 (P < .05). Of 27 patients, 84.4% were satisfied or very satisfied with their general vision. Conclusions: This new lens was similar in terms of visual performance and satisfaction to other trifocal IOLs. It can be classified as a trifocal extended depth of focus IOL because of the performance between extended depth of focus IOLs and medium-high addition trifocal IOLs. [J Refract Surg. 2019;35(4):214-221.].
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PurposeTo assess the degree of posterior capsular opacification (PCO) and its influence on contrast sensitivity defocus curve (CSDC) after implantation of two trifocal intraocular lenses (IOLs), Alsafit (AT) and Liberty (L), during a 12-month follow-up. A secondary aim was to evaluate the Nd:YAG capsulotomy rate in a long time.Methods Data from 63 subjects, 34 implanted with AT and 29 with L, were retrospectively analyzed for this pilot study. In those eyes without capsulotomy during the first year (n = 58), CSDC at 3 and 12 months after surgery and PCO grading were measured, with additional answering of a visual function questionnaire (VF-14) and a question of general satisfaction. The period after surgery up to capsulotomy or last on-demand visit without Nd:YAG was recorded for survival analysis beyond the 12-month follow-up.ResultsTotal area under CSDC (TAUC) between 3 and 12 months decreased from 2.96 to 1.71 for AT (p < 0.05) and from 2.73 to 2.21 (p > 0.05) for L. Of eyes, 51.6, 19.3, and 29% with AT were graded as level 0, 1, and 2 of PCO, while 85.1, 11.1, and 3.7% of eyes with L were graded as level 0, 1, and 2 (p < 0.05). PCO grading was correlated with a decrease of TAUC (ρ = − 0.27, p = 0.04). Median time to require capsulotomy was 22 months with AT and 30 months with L (p < 0.05).ConclusionsPCO decreases CSDC in patients with trifocal lenses. Despite using the same hydrophilic material, PCO grading and Nd:YAG capsulotomy rate was higher for AT than for L.
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Introduction: To establish the most appropriate curve fitting method to allow accurate comparison of defocus curves derived from intraocular lenses (IOLs). Methods: Defocus curves were plotted in five IOL groups (monofocal, extended depth of focus, refractive bifocal, diffractive bifocal and trifocal). Polynomial curves from 2nd to 11th order and cubic splines were fitted. Goodness of fit (GOF) was assessed using five methods: least squares, coefficient of determination (R2 adj ), Akaike information criteria (AIC), visual inspection and Snedecor and Cochran. Additional defocus steps at -2.25 D and -2.75 D were measured and compared to the calculated visual acuity (VA) values. Area under the defocus curve and range of focus were also compared. Results: Goodness of fit demonstrated variable results, with more lenient methods such as R2 adj leading to overfitting and conservative methods such as AIC resulting in underfitting. Furthermore, conservative methods diminished the inflection points resulting in an underestimation of VA. Polynomial of at least 8th order was required for comparison of area methods, but overfitted the EDoF and monofocal groups; the spline curve was consistent for all IOLs and methods. Conclusions: This study demonstrates the inherent difficulty of selecting a single polynomial function. The R2 method can be used cautiously along with visual inspection to guard against overfitting. Spline curves are suitable for all IOLs, guarding against the issues of overfitting. Therefore, for analysis of the defocus profile of IOLs, the fitting of a spline curves is advocated and should be used wherever possible.
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Purpose To investigate the tilt and decentration of the crystalline lens and the intraocular lens (IOL) relative to the corneal topographic axis using anterior segment ocular coherence tomography (AS-OCT). Methods A sample set of 100 eyes from 49 subjects (41 eyes with crystalline lenses and 59 eyes with IOLs) were imaged using second generation AS-OCT (CASIA2, TOMEY) in June and July 2016 at Okayama University. Both mydriatic and non-mydriatic images were obtained, and the tilt and decentration of the crystalline lens and the IOL were quantified. The effects of pupil dilation on measurements were also assessed. Results The crystalline lens showed an average tilt of 5.15° towards the inferotemporal direction relative to the corneal topographic axis under non-mydriatic conditions and 5.25° under mydriatic conditions. Additionally, an average decentration of 0.11 mm towards the temporal direction was observed under non-mydriatic conditions and 0.08 mm under mydriatic conditions. The average tilt for the IOL was 4.31° towards the inferotemporal direction relative to the corneal topographic axis under non-mydriatic conditions and 4.65° in the same direction under mydriatic conditions. The average decentration was 0.05 mm towards the temporal direction under non-mydriatic conditions and 0.08 mm in the same direction under mydriatic conditions. A strong correlation was found between the average tilt and decentration values of the crystalline lens and the IOL under both non-mydriatic and mydriatic conditions (all Spearman correlation coefficients, r ≥ 0.800; all P < 0.001). Conclusion When measured using second generation AS-OCT, both the crystalline lens and the IOL showed an average tilt of 4–6° toward the inferotemporal direction relative to the corneal topographic axis and an average decentration of less than 0.12 mm towards the temporal direction. These results were not influenced by pupil dilation and they showed good repeatability.
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Background Today, patients often expect to achieve spectacle independance after cataract surgery. New trifocal intraocular lenses have been developed to try and fullfill this demand. The purpose of this study is to report the short-term visual outcomes of a new trifocal intraocular lens (AcrySof PanOptix™). Methods Consecutive adult patients undergoing cataract surgery with bilateral implantation of the study intraocular lens in a private practice clinic were considered for inclusion. Exclusion criteria were the presence of other ocular pathologies or preoperative astigmatism >1.5 diopters (D). Patients with intraoperative complications were excluded from analysis. One month after surgery patients underwent: monocular defocus curve; monocular and binocular uncorrected visual acuity in photopic and mesopic conditions, for far (4 m), intermediate (60 cm) and near (33 cm) distances and binocular contrast sensitivity. Patients completed a visual satisfaction questionnaire between 9 and 12 months after surgery. ResultsOne hundred and sixteen eyes of fifty-eight patients receiving bilateral implantation of the study intraocular lens were analysed. Mean binocular uncorrected visual acuity in photopic conditions was 0.03 LogMAR for far, 0.12 for intermediate and 0.02 for near distances. All patients achieved a binocular uncorrected visual acuity better than 0.3 LogMAR (20/40 Snellen equivalent) for distance and near vision and 94.8% of patients for intermediate vision. Mesopic binocular uncorrected visual acuity values were similar to photopic values. The monocular defocus curves showed that the best visual acuity was reached at a vergence of 0.00D. Visual acuity dropped slightly at −1.00D and peaked again at −2.00D. Visual acuities better than 0.2 LogMAR were maintained between −2.50D and +0.50D. Contrast sensitivity was high and similar in photopic and mesopic conditions. As regards patient-evaluated outcomes, only 2 patients (3.4%) were fairly dissatisfied with their sight after surgery. Three patients (5.1%) reported the need for spectacle correction for certain activities. All other patients (94.8%) reported never using spectacle correction. Conclusions The PanOptix trifocal IOL provides good short-term visual outcomes, with good intermediate performance and excellent patient-reported satisfaction. The similar values achieved in mesopic and photopic conditions in binocular uncorrected visual acuity and contrast sensitivity suggest low pupillary dependence for light distribution. Trial registration numberISRCTN60143265, retrospectively registered on the 24th of April 2017.
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Background To evaluate the clinical outcomes after the implantation of a new trifocal diffractive intraocular lens (IOL) combined with Enhanced depth of focus (EDOF) technology. Methods The study enrolled 80 eyes of 40 patients who underwent cataract surgery with bilateral implantation of a diffractive trifocal IOL (Reviol Tri-ED) designed with a combination of enhanced depth of focus. Mean age was 52.09 ± 11.32 years (range from 45 to 70 years). Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), uncorrected intermediate visual acuity (UIVA), corrected intermediate visual acuity (CIVA), uncorrected near visual acuity (UNVA), corrected near visual acuity (CNVA), keratometry (K), and manifest refraction spherical equivalent (MRSE) were evaluated pre- and postoperatively. The contrast sensitivity, defocus curves, and a questionnaire evaluating individual satisfaction were also estimated. ResultsThere was a significant improvement in UDVA, CDVA, UNVA, CNVA, CIVA postoperatively. The defocus curve confirmed good visual acuity also in the intermediate distance. The postoperative MRSE was ranged from −0.75 to 0.75 diopters. Contrast sensitivity also significantly improved postoperatively. The patient satisfaction was high. Conclusion The new trifocal EDOF IOL provides visual improvement for far, intermediate, and near distances with a high level of visual quality and patient satisfaction.
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Purpose. To evaluate visual, refractive, and contrast sensitivity outcomes, as well as the incidence of pseudophakic photic phenomena and patient satisfaction after bilateral diffractive trifocal intraocular lens (IOL) implantation. Methods . This prospective nonrandomized study included consecutive patients undergoing cataract surgery with bilateral implantation of a diffractive trifocal IOL (AT LISA tri 839MP, Carl Zeiss Meditec). Distance, intermediate, and near visual outcomes were evaluated as well as the defocus curve and the refractive outcomes 3 months after surgery. Photopic and mesopic contrast sensitivity, patient satisfaction, and halo perception were also evaluated. Results. Seventy-six eyes of 38 patients were included; 90% of eyes showed a spherical equivalent within ±0.50 diopters 3 months after surgery. All patients had a binocular uncorrected distance visual acuity of 0.00 LogMAR or better and a binocular uncorrected intermediate visual acuity of 0.10 LogMAR or better, 3 months after surgery. Furthermore, 85% of patients achieved a binocular uncorrected near visual acuity of 0.10 LogMAR or better. Conclusions. Trifocal diffractive IOL implantation seems to provide an effective restoration of visual function for far, intermediate, and near distances, providing high levels of visual quality and patient satisfaction.
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Angle kappa is the difference between the pupillary and visual axis. This measurement is of paramount consideration in refractive surgery, as proper centration is required for optimal results. Angle kappa may contribute to MFIOL decentration and its resultant photic phenomena. Adjusting placement of MFIOLs for angle kappa is not supported by the literature but is likely to help reduce glare and haloes. Centering LASIK in angle kappa patients over the corneal light reflex is safe, efficacious, and recommended. Centering in-between the corneal reflex and the entrance pupil is also safe and efficacious. The literature regarding PRK in patients with an angle kappa is sparse but centering on the corneal reflex is assumed to be similar to centering LASIK on the corneal reflex. Thus, centration of MFIOLs, LASIK, and PRK should be focused on the corneal reflex for patients with a large angle kappa. More research is needed to guide surgeons' approach to angle kappa.
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To assess the visual outcomes of aspheric multifocal intraocular lenses (IOLs) compared with spherical multifocal IOL after cataract surgery. Potential prospective controlled trials that comparing aspheric multifocal IOL implantation with spherical multifocal IOL group were extracted from the computer database. The statistical analysis was carried out using Stata 10 software. Standardized mean differences with 95% confidence intervals (CIs) were calculated for continuous variables. The pooled estimates were computed in the use of a random-effects model. A systematic review identified five prospective nonrandomized controlled trials, including 178 aspheric multifocal IOL and 164 spherical multifocal IOL. There was no significant difference in uncorrected distance visual acuity (95%CI, -0.248 to 0.152;P=0.641) and uncorrected near visual acuity (95%CI, -0.210 to 0.428;P=0.504) between aspheric multifocal IOL and spherical multifocal IOL. Statistically significant differences were detected less spherical aberration in aspheric multifocal IOL (95%CI, -1.111 to -0.472; P<0.001) when compared to spherical multifocal IOL. Spherical multifocal IOL showed a greater higher order aberration compared to the aspheric multifocal IOL (95%CI, -1.024 to-0.293; P<0.001). Sensitivity analysis suggested that the results were relatively reliable. The overall findings indicated that aspheric multifocal IOL and spherical multifocal IOL provided similar visual acuity at near and distance. Patients implanted with aspheric multifocal IOL had less spherical aberration and higher order aberration than patients with spherical multifocal IOL. Further well-organized, prospective controlled trials involving larger patient numbers are needed.
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Purpose: To evaluate patient satisfaction with multifocal intraocular lens (MIOL) implants (AcrySof Restor) in relation to the size of angle kappa and precise centration of the MIOL. Methods: Fifty-two eyes of 26 patients were included in this study. All patients underwent bilateral phacoemulsification and multifocal intraocular lens implantation (AcrySof Restor) from January 2008 to April 2010. Preoperative and postoperative examinations included slit lamp biomicroscopy, near and distance uncorrected visual acuity (UCVA) and best-corrected visual acuity (BCVA), contrast sensitivity and measurement of angle kappa. Precise centration of the IOL with respect to the centre of the pupil was evaluated postoperatively. Subjective photic phenomena were evaluated separately for each eye and the patients were asked to compare the perception between the right and left eye. Results: Angle kappa was positive in all cases, ranging from +1° to +7°. The mean angle kappa was 2.78° and 2.10° in the right and left eye, respectively. The IOL was centred exactly to the centre of the pupil in 40 eyes. In twelve eyes there was a slight decentration of the IOL (3 nasal, 4 temporal, 2 superotemporal, 2 superior, 1 inferior). Different subjective perception of photic phenomena between the two eyes was recorded only in five patients. All these patients were among those with a decentred IOL. Temporal and superotemporal decentration of the IOL caused pronounced photic phenomena in five cases - in four cases there was a greater angle kappa of +3° to +4°. In one case of temporal decentration and a small angle kappa (+1°), the patient failed to observe a difference between both eyes. In the cases of inferior, superior and nasal decentration of the IOL, no difference between both eyes was seen. Conclusion: According to our results, temporal decentration of the IOL is associated with the greatest risk in multifocal IOL implantation, particularly in cases with a higher angle kappa. An evaluation of angle kappa should be a part of preoperative examination before MIOL implantation. Patients with a high angle kappa should be excluded because of a higher risk of postoperative photic phenomena. Key words: angle kappa, multifocal intraocular lens, photic phenomena.
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To evaluate the visual acuity and quality-related satisfaction of patients implanted with a refractive design multifocal intraocular lens (IOL), and evaluate the factors predicting it including angle kappa. Dr Agarwal's Eye Hospital and Eye Research Centre, Chennai. In this prospective trial, 50 eyes of 44 consecutive patients were included. All patients underwent phacoemulsification with multifocal IOL implantation (Rezoom IOL, Abbott Medical Optics). The preoperative and postoperative assessment included slit lamp biomicroscopy, uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA) and kappa angle assessment. At 1 year, 37 patients (43 eyes), who finished follow-up, were asked to rate their symptoms on a graded questionnaire (0-5 for five queries). The decimal scores for UCVA and BCVA were 0.38±0.21 and 0.47±0.17 (preoperative), and 0.75±0.22 and 0.99±0.11 (postoperative), respectively. Symptom scores were haloes 0.98±1.7, glare 0.69±1.48, blurred distance 1.0±1.7, intermediate 1.34±1.6, near 1.06±1.8. On regression analysis haloes depended on angle kappa and distance UCVA (R (2)=0.26, P=0.029), and glare on angle kappa (R (2)=0.26, P=0.033). Poor satisfactions with distance, intermediate, and near vision were linked with distance UCVA (R (2)=0.17, P=2.3 × 10(-4)), distance UCVA (R (2)=0.1, P=0.04), and near UCVA (R (2)=0.12, P=0.03), respectively. The strongest predictor, however, for overall visual discomfort was distance UCVA (R (2)=0.1, P=0.04). Our study suggests that there may be a role of misalignment between the visual and pupillary axis (angle kappa) in the occurrence of photic phenomenon after refractive multifocal IOL implantation.
Article
Purpose To compare objective methods for assessing backward and forward light scatter and psychophysical tests in patients with cataracts. Setting Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom. Design Prospective case series. Methods This study included patients scheduled for cataract surgery. Lens opacities were grouped into predominantly nuclear sclerotic, cortical, posterior subcapsular, and mixed cataracts. Backward light scatter was assessed using a rotating Scheimpflug imaging technique (Pentacam HR), forward light scatter using a straylight meter (C-Quant), and straylight using the double-pass method (Optical Quality Analysis System, point-spread function [PSF] meter). The results were correlated with visual acuity under photopic conditions as well as photopic and mesopic contrast sensitivity. Results The study comprised 56 eyes of 56 patients. The mean age of the 23 men and 33 women was 71 years (range 48 to 84 years). Two patients were excluded. Of the remaining, 15 patients had predominantly nuclear sclerotic cataracts, 13 had cortical cataracts, 11 had posterior subcapsular cataracts, and 15 had mixed cataracts. Correlations between devices were low. The highest correlation was between PSF meter measurements and Scheimpflug measurements (r = 0.32). The best correlation between corrected distance visual acuity was with the PSF meter (r = 0.45). Conclusions Forward and backward light-scatter measurements cannot be used interchangeably. Scatter as an aspect of quality of vision was independent of acuity. Measuring forward light scatter with the straylight meter can be a useful additional tool in preoperative decision-making.
Article
Purpose To evaluate the preoperative clinical and biometric determinants associated with the actual lens position after cataract surgery. Setting Department of Ophthalmology, University Hospital of Montpellier, France. Design Prospective longitudinal cohort study. Methods The data collected included clinical factors (age, sex, history of vitrectomy) and biometry factors (axial length [AL], anterior chamber depth [ACD], lens thickness, white-to-white [WTW] distance) that might affect actual lens position. Each patient had optical low-coherence reflectometry biometry (Lenstar) preoperatively and 1 month postoperatively. The actual lens position was measured as the postoperative position of the center of the intraocular lens (IOL). Patients were stratified into 3 groups by type of IOL: Acrysof SN60WF or SN6AT (Group 1), Tecnis ZCB00 or ZCT (Group 2), and Asphina 409 MV (Group 3). Results The study comprised 168 eyes (mean age 73.3 years ± 9.8 [SD]). The mean actual lens position was 4.88 ± 0.29 mm, 5.01 ± 0.29 mm, and 5.05 ± 0.32 mm in Group 1 (n = 67 eyes), Group 2 (n = 52 eyes), and Group 3 (n = 49 eyes), respectively. In the overall population, AL, ACD, anterior segment depth, and WTW distance were correlated with actual lens position (r = 0.48, P < .0001; r = 0.64, P < .001; r = 0.58, P < .0001; r = 0.39, P < .001, respectively). Conclusions The AL, ACD, anterior segment depth, and WTW distance correlated with actual lens position after cataract surgery. The integration of these data in IOL formulas could help improve refractive outcomes after the surgery.
Article
Purpose: To compare visual outcomes after cataract surgery with bilateral implantation of 2 intraocular lenses (IOLs): extended range of vision and trifocal. Methods: Each group of this prospective study comprised 40 eyes (20 patients). Phacoemulsification followed by bilateral implantation of a FineVision IOL (group 1) or a Symfony IOL (group 2) was performed. The following outcomes were assessed up to 1 year postoperatively: binocular uncorrected distance visual acuity (UDVA), binocular uncorrected intermediate visual acuity (UIVA) at 60 cm, binocular uncorrected near visual acuity (UNVA) at 40 cm, spherical equivalent (SE) refraction, defocus curves, mesopic and photopic contrast sensitivity, halometry, posterior capsule opacification (PCO), and responses to a patient questionnaire. Results: The mean binocular values in group 1 and group 2, respectively, were SE -0.15 ± 0.25 D and -0.19 ± 0.18 D; UDVA 0.01 ± 0.03 logMAR and 0.01 ± 0.02 logMAR; UIVA 0.11 ± 0.08 logMAR and 0.09 ± 0.08 logMAR; UNVA 0.06 ± 0.07 logMAR and 0.17 ± 0.06 logMAR. Difference in UNVA between IOLs (p<0.05) was statistically significant. There were no significant differences in contrast sensitivity, halometry, or PCO between groups. Defocus curves were similar between groups from 0 D to -2 D, but showed significant differences from -2.50 D to -4.00 D (p<0.05). Conclusions: Both IOLs provided excellent distance and intermediate visual outcomes. The FineVision IOL showed better near visual acuity. Predictability of the refractive results and optical performance were excellent; all patients achieved spectacle independence. The 2 IOLs gave similar and good contrast sensitivity in photopic and mesopic conditions and low perception of halos by patients.
Article
Objective: To evaluate the accuracy of predicting the spectacle plane add power of multifocal intraocular lenses (MIOLs) based on the effective lens position (ELP) using the Haigis formula. Design: Retrospective cross-sectional study. Participants: A total of 26 eyes from 18 consecutive patients who underwent phacoemulsification with Tecnis MIOL (Z*B00) implantation. Methods: The postoperative spectacle plane add power of MIOLs was determined from the monocular defocus curve. The predicted add power error was defined as the difference between the predicted and postoperatively measured spectacle plane add power. The median absolute predicted add power error determined by the preoperatively estimated ELP using the Haigis formula was compared with power error calculated using the value presented by the manufacturer. The correlations among predicted add power error, postoperative spectacle plane add power, and back-calculated ELP were analyzed. Results: The median absolute predicted add power error calculated using the Haigis formula (0.13 D) was significantly smaller than that calculated using the value presented by the manufacturer (0.26 D). The predicted add power error determined by the value presented by the manufacturer was negatively correlated with back-calculated ELP. The postoperative spectacle plane add power was negatively correlated with back-calculated ELP in the ZKB00 IOL (n = 21). Conclusions: The predicted spectacle plane add power of MIOLs using the ELP of the Haigis formula was more accurate than that using the value presented by the manufacturer. The spectacle plane add power of MIOLs decreased as ELP increased.
Article
Purpose: To analyze the effect of decentration on the optical quality of two diffractive-refractive intraocular lenses, a bifocal and a trifocal, when displaced laterally (horizontal direction) from the center. Methods: The AT LISA 809M IOL (+3.75 D add) with two main foci and the AT LISA tri 839MP intraocular lens with three main foci (Carl Zeiss Meditec AG, Jena, Germany) were analyzed. The optical quality of the intraocular lenses was measured with the PMTF (power and modulation transfer function [MTF] measurement for refractive and diffractive intraocular lenses) optical bench (Lambda-X, Nivelles, Belgium). The optical quality of the lenses was evaluated by the MTF at different object vergences, the average modulation in the range of frequencies from 0 to 100 cycles/mm, and the through-focus MTF curves. All measures were recorded when the intraocular lenses were centered and decentered for 3.0- and 4.5-mm apertures. The Strehl ratio and the percentage of energy allocated at each focus at the centered position were also obtained. Results: Our results showed a lower optical quality with increasing decentration. The MTFs for the diffractive-refractive intraocular lenses decreased when the intraocular lenses were decentered. Also, the relative percentages of light energy allocated at each object vergence, for both intraocular lenses, agreed well with theoretical specifications and were consistent with the overall design of each lens. Conclusions: The optical quality of these diffractive-refractive multifocal intraocular lenses was slightly reduced when the induced decentration was less than 0.4 mm. For a decentration of 0.4 mm, the maximum difference in average modulation values was about 18% compared to the centered position.
Article
Purpose: To investigate the visual outcomes between mix-and-match bifocal intraocular lenses (IOLs) (ReSTOR +2.50 and +3.00 diopters [D]; Alcon Laboratories, Inc., Fort Worth, TX) versus bilateral implantation of a trifocal IOL (FineVision; PhysIOL, Liège, Belgium). Methods: Twenty-three patients (average age: 56.3 ± 6.9 years; range: 45 to 71 years) referred for lens phacoemulsification and IOL implantation were included in this study. Patients were randomly assigned to two groups. The FineVision group was bilaterally implanted with the FineVision trifocal IOL and the ReSTOR group was implanted with mix-and-match bifocal ReSTOR +2.50 and +3.00 D IOLs. A 3-month postoperative check was performed, and manifest refraction and logMAR uncorrected (UDVA) and corrected (CDVA) distance and near visual acuities were recorded. Monocular and binocular defocus curve testing was performed under photopic (85 cd/m(2)) conditions in 0.50-D defocus steps. Contrast sensitivity was measured monocularly and binocularly under mesopic conditions at spatial frequencies of 3, 6, 12, and 18 cycles per degree using the CSV-1000 contrast test (VectorVision, Greenville, OH). Results: There were no reported differences in monocular distance visual acuity or refractive outcomes between groups (P > .05). Furthermore, there were no significant differences in contrast sensitivity between the three IOLs (P > .05). The FineVision group achieved better monocular and binocular near and intermediate visual acuities under defocus curve testing than the ReSTOR group (P < .05). Conclusions: Binocular implantation of the FineVision trifocal IOL provided a better range of visual acuities at near and intermediate distances than mix-and-match bifocal IOL implantation. [J Refract Surg. 2016;32(10):659-663.].
Article
Purpose: To compare the visual results and patient satisfaction after bilateral implantation between a bifocal and a trifocal intraocular lens (IOL). Methods: This study is a prospective, randomized, controlled study involving bilateral implantation of one of two multifocal IOLs. Patients were assessed for uncorrected and distance-corrected near (33 cm), intermediate (66 cm), and distance visual acuity. Distance contrast sensitivity under photopic (85 cd/m(2)) conditions with and without glare was also measured. Using a subjective questionnaire, patient satisfaction, spectacle independence, and the perception of glare and halo phenomena were evaluated at the final follow-up; a defocus curve analysis was conducted. Results: Fifteen patients (30 eyes) were implanted with the FineVision IOL (PhysIOL, Liége, Belgium) and 12 patients (24 eyes) received the Tecnis ZMB00 IOL (Abbott Medical Optics, Santa Ana, CA). The average follow-up was 6 months. The mean binocular uncorrected visual acuity was 0.02 ± 0.04 logMAR in the FineVision group and 0.04 ± 0.05 logMAR in the Tecnis group and the mean binocular uncorrected near visual acuity was 0.01 ± 0.00 logMAR in both groups. In the intermediate range of the defocus curve, there was a statistically significant difference between the two IOLs (P < .05). Contrast sensitivity was within normal limits under photopic conditions in both groups. Conclusions: Both the Tecnis and FineVision IOLs provide a satisfactory range of vision, including a high level of uncorrected distance, intermediate, and near acuity and improved contrast sensitivity under photopic conditions. [J Refract Surg. 2016;32(3):146-151.].
Article
Purpose: To calculate the near focal distance of different multifocal intraocular lenses (IOLs) as a function of the 2 parameters that are measured before cataract surgery; that is, axial length (AL) and refractive corneal power (keratometry [K]). Setting: GB Bietti Foundation IRCCS, Rome, Italy. Design: Noninterventional theoretical study. Methods: The IOL power for emmetropia was first calculated in an eye model with the AL ranging from 20 to 30 mm and K from 38 to 48 diopters (D). Then, the predicted myopic refraction for any given IOL add power (from +1.5 to +4.0 D) was calculated, and from this value the near focal distance was obtained. Calculations were also performed for the average eye (K = 43.81 D; AL = 23.65 mm). Results: The near focal distance increased with increasing values of K and AL for each near power add. The near focal distance ranged between 53 cm and 72 cm (21 inches and 28 inches) for a multifocal IOL with +2.50 D, between 44 cm and 60 cm (17 inches and 24 inches) for a multifocal IOL with +3.00 D add, and between 33 cm and 44 cm (13 inches and 18 inches) for a multifocal IOL with +4.00 D add. In the average eye, the near focal distance ranges between 36 cm (near add power = 4.00 D) and 99 cm (near add power = 1.5 D). Conclusions: Longer eyes with steeper corneas showed the longest near focal distance and could experience more difficulties in focusing near objects after surgery. The opposite was true for short hyperopic eyes. Financial disclosure: Dr. Hoffer receives licensing fees for the commercial use of the registered trademark Hoffer from all biometry manufacturers using the Hoffer Q formula to ensure that it is programmed correctly and book royalties from Slack, Inc., for the textbook IOL Power. None of the authors has a financial or proprietary interest in any material or method mentioned.
Article
Purpose: To determine the effect of lens position and corneal curvature on the near focal point of different multifocal intraocular lenses. Methods: Near focal points for various multifocal intraocular lenses were calculated using a refractive vergence formula. Median, high, and low values for lens position and corneal curvature were used. Results: Lens position and corneal curvature both affected the theoretical near point of multifocal intraocular lenses. The effect was more pronounced for lower power adds. There was overlap of near focal points for the different near adds of the Tecnis multifocal lenses (AMO, Abbott Park, IL) across the range of lens positions and corneal curvatures seen in a normal population. Conclusions: Clinicians need to be aware of the effect of lens position and corneal curvature on the near focal point of intraocular lenses. [J Refract Surg. 2016;32(1):64-66.].
Article
Purpose: To compare visual outcomes in patients with cataract surgery and bilateral implantation of a trifocal or bifocal intraocular lens (IOL). Setting: University Eye Clinic Maastricht, the Netherlands. Design: Prospective randomized clinical trial. Methods: Eyes with cataract and less than 1.0 diopter (D) of corneal astigmatism were randomized to receive bilateral implantation of Finevision Micro F trifocal IOLs or Acrysof IQ Restor +3.0 bifocal IOLs. Outcome measures were monocular and binocular uncorrected distance (UDVA), uncorrected intermediate (UIVA), and uncorrected near (UNVA) visual acuities; refractive outcomes; binocular defocus curve; contrast sensitivity; reading speed; patient satisfaction; and spectacle independence. Results: Six months postoperatively, the mean binocular UDVA, UIVA, and UNVA in 56 eyes of 28 patients were 0.01 logMAR ± 0.11 (SD), 0.32 ± 0.15 logMAR, and 0.15 ± 0.13 logMAR in the trifocal group (n = 15) and 0.00 ± 0.09 logMAR, 0.28 ± 0.08 logMAR, and 0.12 ± 0.08 logMAR in the bifocal group (n = 13), respectively. The trifocal group showed a more continuous defocus curve and better results at -1.0 D of defocus (P < .01). The mean mesopic contrast sensitivity was higher in the bifocal group (P = .02). Complete spectacle independence was reported by 80% of trifocal patients and 50% of bifocal patients. There were no significant differences in refractive outcomes, reading speed, or patient satisfaction. Conclusion: This study showed noninferiority of visual outcomes with the trifocal IOL compared with the bifocal IOL, although the defocus curve was better at an intermediate distance with the trifocal IOL. Financial disclosure: Dr. Bauer received study grants from Alcon Laboratories, Inc., Carl Zeiss Meditec AG, and Physiol S.A. and a lecture fee from Alcon Surgical, Inc. Dr. Nuijts is a consultant to Alcon Surgical, Inc., Théa Pharma GmbH, and ASICO LLC; he has received study grants from Acufocus, Inc., Alcon Surgical, Inc., Carl Zeiss Meditec AG, Ophtec BV, and Physiol S.A. No other author has a financial or proprietary interest in any material or method mentioned.
Article
Purpose To evaluate the visual, refractive, contrast-sensitivity, and aberrometric outcomes during a 1-year follow-up after implantation of a trifocal intraocular lens (IOL). Setting Premium Clinic, Teplice, Czech Republic. Design Prospective case series. Methods This study included eyes of patients having cataract surgery with implantation of the trifocal IOL model AT Lisa tri 839MP. Distance, intermediate (66 and 80 cm), and near (33 and 40 cm) vision; contrast sensitivity; aberrometric outcomes; and the defocus curve were evaluated during a 12-month follow-up. The level of posterior capsule opacification (PCO) was also evaluated. Results In 120 eyes (60 patients), 1 month postoperatively, an improvement was observed in all visual parameters (P ≥03) except corrected near and intermediate visual acuities (both P ≤.05). From 1 month to 12 months postoperatively, small but statistically significant changes were observed in uncorrected and corrected distance and near visual acuities (all P ≥;.03) and in uncorrected intermediate visual acuity (P =.01). In the defocus curve, no significant differences were found between visual acuities corresponding to defocus levels of -1.0 diopter (D) and -2.0 D (P =.22). The level of ocular spherical aberration decreased statistically significantly at 6 months (P <.001). Ocular and internal higher-order aberrations increased minimally but significantly from 6 to 12 months postoperatively (P <.001). The mean 12-month PCO score was 0.32 ± 0.44 (SD). Four eyes (3.3%) required neodymium:YAG capsulotomy. Conclusion The trifocal IOL provided complete and stable visual restoration after cataract surgery during a 12-month follow-up, with good levels of visual quality. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.
Article
Purpose: To evaluate visual and refractive outcomes after implantation of a trifocal intraocular lens (IOL). Design: Prospective, nonrandomized noncomparative case series. Methods: • Setting: Department of Ophthalmology, Goethe University, Frankfurt/Germany. • Patient or Study Population: 27 patients (54 eyes) who had bilateral implantation of the AT LISA trifocal IOL (AT LISA tri839MP, Zeiss) pre-enrollment. Exclusion criteria were previous ocular surgeries excluding cataract surgery and refractive lens exchange, irregular corneal astigmatism of > 1.5 D and ocular pathologies or corneal abnormalities. • Intervention or Observation Procedure(s): Postoperative examination at 1 and 3 months included manifest refraction, monocular and binocular uncorrected (UCVA) and distance corrected (DCVA) visual acuity in 4m, 80cm and 40cm, slit lamp examination and tomography. At 3 months defocus testing, binocular contrast sensitivity (CS) under photopic and mesopic conditions and a questionnaire on subjective quality of vision, optical phenomena and spectacle independence were performed. • Main Outcome Measure(s): 3 months postoperative monocular and binocular UCVA and DCVA in 4m, 80cm and 40cm (LogMAR), defocus curve, CS and quality of vision questionnaire results. Results: Mean spherical equivalent was 0.05 ± 0.32 D 3 months postoperative. Binocular UCVA at distance, intermediate and near was -0.1 ± 0.1 logMAR, 0.0 ± 0.1 logMAR and 0.0 ± 0.1 logMAR, respectively. Despite some optical phenomena, 92% of patients would choose the same IOL again. Conclusion: Evaluation of a trifocal IOL showed good VA (0.1 logMAR or better) at far, intermediate and near distance, high patient satisfaction despite some optical phenomena and high spectacle independence 3 months postoperatively.
Article
Purpose: To examine the influence of astigmatism on the visual acuity of patients with multifocal and monofocal intraocular lenses. Methods: Thirty eyes of 30 patients who underwent five-zone refractive multifocal intraocular lens implantation and 30 eyes of 30 age-matched patients who had monofocal intraocular lens implantation were included. The visual acuities of these patients at 5.0, 3.0, 2.0, 1.0, 0.7, 0.5, and 0.3 m were measured by means of an all-distance vision tester after addition of a cylindrical lens of 0, 0.5, 1.0, 1.5, 2.0, and 2.5 diopters. Results: Mean visual acuity at all distances decreased in proportion to the diopters of astigmatism in both the multifocal and monofocal intraocular lens groups. When astigmatism was 0.5, 1.0, or 1.5 diopters, distance visual acuity in the multifocal group was significantly worse than that in the monofocal group; with astigmatism of 2.0 diopters or more, intermediate visual acuity was also worse in the multifocal group. In contrast, near visual acuity in the multifocal group was significantly better than that in the monofocal group at all astigmatic diopters. When astigmatism was within 1.0 diopter, visual acuity in the multifocal group reached 20/29 at distance and 20/50 at near. Mean contrast sensitivity was also worse in the multifocal group than in the monofocal group. Conclusions: Both distance and intermediate visual acuity deterioration caused by astigmatism was greater with a multifocal intraocular lens than with a monofocal intraocular lens, whereas near visual acuity was better with the multifocal intraocular lens. When astigmatism was within 1.0 diopter, eyes with a multifocal intraocular lens achieved good visual acuity at both distance and near.
Article
To investigate the correlations existing between a trifocal intraocular lens (IOL) and a varifocal IOL using the "ex vivo" optical bench through-focus image quality analysis and the clinical visual performance in real patients by study of the defocus curves. This prospective, consecutive, nonrandomized, comparative study included a total of 64 eyes of 42 patients. Three groups of eyes were differentiated according to the IOL implanted: 22 eyes implanted with the varifocal Lentis Mplus LS-313 IOL (Oculentis GmbH, Berlin, Germany); 22 eyes implanted with the trifocal FineVision IOL (Physiol, Liege, Belgium), and 20 eyes implanted with the monofocal Acrysof SA60AT IOL (Alcon Laboratories, Inc., Fort Worth, TX). Visual outcomes and defocus curve were evaluated postoperatively. Optical bench through-focus performance was quantified by computing an image quality metric and the cross-correlation coefficient between an unaberrated reference image and captured retinal images from a model eye with a 3.0-mm artificial pupil. Statistically significant differences among defocus curves of different IOLs were detected for the levels of defocus from -4.00 to -1.00 diopters (D) (P < .01). Significant correlations were found between the optical bench image quality metric results and logMAR visual acuity scale in all groups (Lentis Mplus group: r = -0.97, P < .01; FineVision group: r = -0.82, P < .01; Acrysof group: r = -0.99, P < .01). Linear predicting models were obtained. Significant correlations were found between logMAR visual acuity and image quality metric for the multifocal and monofocal IOLs analyzed. This finding enables surgeons to predict visual outcomes from the optical bench analysis. [J Refract Surg. 2015;31(5):300-307.]. Copyright 2015, SLACK Incorporated.
Article
Purpose To compare the visual outcomes after cataract surgery with bilateral implantation of 1 of 2 diffractive trifocal intraocular lenses (IOLs). Setting Two clinical centers, Lisbon, Portugal. Design Prospective comparative case series. Methods Phacoemulsification with bilateral implantation of a Finevision Micro F IOL (Group 1) or an AT Lisa tri 839 MP IOL (Group 2) was performed. Over a 3-month follow-up, the main outcome measures were uncorrected distance visual acuity (UDVA), corrected monocular and binocular distance visual acuity, uncorrected intermediate visual acuity at 80 cm, distance-corrected intermediate visual acuity (DCIVA), uncorrected near visual acuity at 40 cm, distance-corrected near visual acuity (DCNVA), spherical equivalent (SE) refraction, defocus curves, contrast sensitivity, presence of dysphotopsia, and use of spectacles. Results Each group comprised 30 eyes (15 patients). The mean values at 3 months were UDVA, 0.03 logMAR ± 0.08 (SD) (Group 1) and 0.08 ± 0.12 (Group 2) (P = .765); DCIVA, 0.04 ± 0.07 logMAR and 0.18 ± 0.18 logMAR, respectively (P = .048); DCNVA, 0.03 ± 0.06 logMAR and 0.11 ± 0.08 logMAR, respectively (P = .032); SE, −0.25 ± 0.30 diopter (D) and −0.02 ± 0.39 D, respectively (P = .087). There was no significant difference in contrast sensitivity or dysphotopic phenomena between groups. Conclusions Both trifocal IOL models provided excellent distance, intermediate, and near visual outcomes. Monocular DCIVA and DCNVA appeared slightly better in Group 1. Predictability of the refractive results and optical performance were excellent, and all patients achieved spectacle independence.
Article
Purpose: To compare postoperative changes in apparent photopic and mesopic pupil size and centration in relation to cornea reflection landmarks after cataract surgery. Setting: LaserVision.gr Clinical and Research Eye Institute, Athens, Greece. Design: Prospective consecutive case study. Methods: Pupils were imaged for pupil size and corneal vertex location before and 1-month after cataract surgery. Digital analysis of pupil images was used to determine the Cartesian coordinates (nasal-temporal, horizontal axis, superior-inferior, vertical axis) of the first Purkinje reflection point (approximating the corneal intersection of the visual axis [corneal vertex]) to the pupil geometric center (approximating the corneal intersection of the line of sight [corneal apex]). Pupil size changes were measured, and the correlation between vertex-to-apex shift changes and postoperative pupil centroid shift was evaluated. Results: The study evaluated 40 eyes. The pupil size (diameter) change corresponded to a relative reduction of -9.8% for photopic pupils and -9.1% for mesopic pupils; the difference was statistically significant (P = .045 and P = .011, respectively). Also, there was a reduction in the centroid shift (all eyes) from a mean of 0.12 mm preoperatively to 0.05 mm postoperatively as a result of the postoperative minus temporal horizontal difference between the corneal vertex and the apex. Conclusions: Cataract extraction surgery appears to affect pupil size and centration. Specifically, a smaller pupil and less temporal shift were recorded. These data may have clinical relevance in targeted intraoperative intraocular lens centration. Financial disclosure: Dr. Kanellopoulos is a consultant to Alcon Surgical, Inc., Wavelight Laser Technologie AG, Allergan, Avedro, Inc., and i-Optics Corp. No author has a financial or proprietary interest in any material or method mentioned.
Article
PurposeTo determine the critical value of the angle kappa in connection with a higher risk of photic phenomena for the AcrySof ReSTOR and Tecnis multifocal intra-ocular lens (MIOL) on a standardized pseudophakic eye model. To analyse the impact of biometric value changes on the critical angle kappa.Methods Geometrical optic rules applied to a suitable optical model of the pseudophakic eye were used to calculate the critical value of the angle kappa for the Tecnis and three types of the AcrySof ReSTOR MIOLs. The angle kappa was defined as critical if the incident ray passed through the first ring's edge area. The influence of different positive optical corneal power (K), effective lens position (ELP) and axial length (AL) on the critical angle kappa (κc) was investigated. The dependence of κc on one of the parameters was studied for standardized values of the remaining parameters.ResultsThe highest value of the critical angle kappa was evaluated for the Tecnis MIOL. The increase in ELP and K caused an increase in κc under the given conditions. On the contrary, an increase in AL led to lower values of κc.Conclusion We demonstrated the dependence of the critical angle kappa on the central part of the MIOL and on biometric parameters of the eye, especially on the effective lens position. According to these results, we conclude that shallow anterior chamber depth in connection with a higher angle kappa is an important risk factor for pronounced photic phenomena after implantation of a diffractive MIOL.
Article
Purpose To describe the inconsistencies in definition, application, and usage of the ocular reference axes (optical axis, visual axis, line of sight, pupillary axis, and topographic axis) and angles (angle kappa, lambda, and alpha) and to propose a precise, reproducible, clinically defined reference marker and axis for centration of refractive treatments and devices. Design Perspective Methods Literature review of papers dealing with ocular reference axes, angles, and centration Results The inconsistent definitions and usage of thecurrent ocular axes, as derived from eye models, limit their clinical utility. With a clear understanding of Purkinje images and a defined alignment of the observer, light source/fixation target, and subject eye, the subject-fixated coaxially sighted corneal light reflex can be a clinically useful reference marker. The axis formed by connecting the subject-fixated coaxially sighted corneal light reflex and the fixation point, the subject-fixated coaxially sighted corneal light reflex axis, is independent of pupillary dilation and phakic status of the eye. The relationship of the subject-fixated coaxially sighted corneal light reflex axis to a refined definition of the visual axis without reference to nodal points, the foveal-fixation axis, is discussed. The displacement between the subject-fixated coaxially sighted corneal light reflex and pupil center is described not by an angle, but by a chord, here termed chord mu. The application of the subject-fixated coaxially sighted corneal light reflex to the surgical centration of refractive treatments and devices is discussed. Conclusion As a clinically defined reference marker, the subject-fixated coaxially sighted corneal light reflex avoids the shortcomings of current ocular axes for clinical application and may contribute to better consensus in the literature and improved patient outcomes.
Article
To evaluate refractive and visual parameters related to distance, intermediate, and near vision after cataract surgery and the optical quality of a new diffractive trifocal intraocular lens (IOL). Vissum Instituto Oftalmologico de Alicante, Alicante, Spain. Case series. Patients had bilateral refractive lens exchange and multifocal diffractive IOL (AT Lisa tri 839 MP) implantation. A complete ophthalmology examination was performed preoperatively and postoperatively. The follow-up was 6 months. The main outcome measures were uncorrected distance (UDVA) and corrected distance (CDVA), intermediate, and near visual acuities; keratometry; manifest refraction; and aberrations (total, corneal, internal). The study comprised 60 eyes of 30 patients (mean age 57.9 years ± 7.8 [SD]; range 42 to 76 years). There was significant improvement in UDVA, uncorrected intermediate visual acuity, uncorrected near visual acuity, CDVA, and distance-corrected intermediate and near visual acuity. The postoperative refractive status was within the range of +1.00 to -1.00 diopter. Total internal aberrations decreased significantly (P<.001). The trifocal IOL improved near, intermediate, and distance vision in presbyopic patients. The use of 3 foci provided significant intermediate visual results without sacrificing near or distance vision. No author has a financial or proprietary interest in any material or method mentioned.
Article
To determine the most appropriate analysis technique for the differentiation of multifocal intraocular lens (MIOL) designs by using defocus curve assessment of visual capability. Four groups of 15 subjects were implanted bilaterally with either monofocal intraocular lenses, refractive MIOLs, diffractive MIOLs, or a combination of refractive and diffractive MIOLs. Defocus curves between -5.0 D and +1.5 D were evaluated by using an absolute and relative depth-of-focus method, the direct comparison method, and a new "area-of-focus" metric. The results were correlated with a subjective perception of near and intermediate vision. Neither depth-of-focus method of analysis was sensitive enough to differentiate between MIOL groups (P > 0.05). The direct comparison method indicated that the refractive MIOL group performed better at +1.00 diopter (D), -1.00 D, and -1.50 D and worse at -3.00 D, -3.50 D, -4.00 D, and -5.00 D than did the diffractive MIOL group (P < 0.05). The area-of-focus intermediate zone was greater with the refractive than with the diffractive MIOL group (P = 0.005) and the near zone was better with the diffractive (P = 0.020) and "mix and match" (P = 0.039) groups than with the refractive MIOL group. The subjective perception of intermediate and near vision agreed best with the area-of-focus metric for the intermediate (r(s) = 0.408, P = 0.010) and near zone (r(s) = 0.484, P < 0.001). Conventional depth-of-focus metrics provide a single value to quantify the useful range of vision; however, they fail to provide sufficient detail to differentiate between MIOL designs. The direct comparison method provides a large amount of information, although the results can be complex to interpret. The proposed area-of-focus metric provides a simple, but differentiating method of evaluating MIOL defocus curves.
Article
To analyze the symptoms, etiology, and treatment of patient dissatisfaction after multifocal intraocular lens (IOL) implantation. Department of Ophthalmology, Maastricht University Medical Center, The Netherlands. Case series. In this retrospective chart review, the main outcome measures were type of complaints, uncorrected and corrected distance visual acuities, uncorrected and distance-corrected near visual acuities, refractive state, pupil diameter and wavefront aberrometry measurements, and type of treatment. Seventy-six eyes of 49 patients were included. Blurred vision (with or without photic phenomenon) was reported in 72 eyes (94.7%) and photic phenomena (with or without blurred vision) in 29 eyes (38.2%). Both symptoms were present in 25 eyes (32.9%). Residual ametropia and astigmatism, posterior capsule opacification, and a large pupil were the 3 most significant etiologies. Sixty-four eyes (84.2%) were amenable to therapy, with refractive surgery, spectacles, and laser capsulotomy the most frequent treatment modalities. Intraocular lens exchange was performed in 3 cases (4.0%). The cause of dissatisfaction after implantation of a multifocal IOL can be identified and effective treatment measures taken in most cases.
Article
To evaluate visual outcomes and patient satisfaction after implantation of an aspheric apodized diffractive intraocular lens (IOL) or a spherical apodized diffractive IOL in cataract surgery. Maastricht University Medical Center, The Netherlands. Nonrandomized clinical trial. This prospective nonrandomized study with a 6-month follow-up compared the results of cataract surgery with implantation of an aspheric AcrySof ReSTOR SN6AD3 IOL and a spherical AcrySof ReSTOR SN60D3 IOL. Main outcome measures were uncorrected (UDVA) and corrected (CDVA) distance visual acuities, uncorrected (UNVA) and distance-corrected (DCNVA) near visual acuities, straylight levels, incidence of glare and halos, and contrast sensitivity levels. The mean UDVA was 0.14 ± 0.15 logMAR in the aspheric group (47 eyes) and 0.14 logMAR ± 0.17 (SD) in the spherical group (45 eyes) and the mean CDVA, -0.01 ± 0.06 logMAR and 0.02 ± 0.10 logMAR, respectively. The mean UNVA was Jaeger (J) 1 in 83.0% of patients in the aspheric group and 55.5% of patients in the spherical IOL group (P = .003). The DCNVA was J1 in 95.7% and 71.1%, respectively (P = .001). There were no significant differences between the 2 groups in contrast sensitivity levels, intraocular straylight levels, incidence of night-vision symptoms, or subjective rating of vision. Patients with the aspheric multifocal IOL had significantly better near vision than patients with the multifocal spherical IOL. The UDVA, CDVA, intraocular straylight, night-vision symptoms, and contrast sensitivity were similar between the 2 groups.
Article
To examine the effect of astigmatism on visual acuity at various distances in eyes with a diffractive multifocal intraocular lens (IOL). Hayashi Eye Hospital, Fukuoka, Japan. In this study, eyes had implantation of a diffractive multifocal IOL with a +3.00 diopter (D) addition (add) (AcrySof ReSTOR SN6AD1), a diffractive multifocal IOL with a +4.00 D add (AcrySof ReSTOR SN6AD3), or a monofocal IOL (AcrySof SN60WF). Astigmatism was simulated by adding cylindrical lenses of various diopters (0.00, 0.50, 1.00, 1.50, 2.00), after which distance-corrected acuity was measured at various distances. At most distances, the mean visual acuity in the multifocal IOL groups decreased in proportion to the added astigmatism. With astigmatism of 0.00 D and 0.50 D, distance-corrected near visual acuity (DCNVA) in the +4.00 D group and distance-corrected intermediate visual acuity (DCIVA) and DCNVA in the +3.00 D group were significantly better than in the monofocal group; the corrected distance visual acuity (CDVA) was similar. The DCNVA with astigmatism of 1.00 D was better in 2 multifocal groups; however, with astigmatism of 1.50 D and 2.00 D, the CDVA and DCIVA at 0.5m in the multifocal groups were significantly worse than in the monofocal group, although the DCNVA was similar. With astigmatism of 1.00 D or greater, the mean CDVA and DCNVA in the multifocal groups reached useful levels (20/40). The presence of astigmatism in eyes with a diffractive multifocal IOL compromised all distance visual acuities, suggesting the need to correct astigmatism of greater than 1.00 D. No author has a financial or proprietary interest in any material or method mentioned.
Article
We analyze theoretically, by means of both computer simulations and laboratory experiments, the limitations of correcting aberrations with ideal customized contact lenses. Four experiments are presented: In the first one, we have analyzed the limitations of a static correction on the dynamic wavefront. In the second one, we studied the rotations of a contact lens on the eye using an optical method. The third one researched the limitations of the wavefront correction, focusing on a group of normal and highly aberrated eyes, when the correction suffers from a permanent rotation or translation. The fourth one estimates, under a simple approximation, the error made when applying on the corneal plane the correction corresponding to the wavefront measured at the entrance-pupil plane. Results show that a static correction of the wavefront leaves a residual aberration of 0.15-0.25 microm for a 5 mm pupil. Rotation of the contact lens (up to +/-4 degrees) diminishes the effectiveness of the correction. Horizontal or vertical translations of 0.5mm could generate a high-order-aberration RMS that is higher than the remaining one after a standard low-order correction. In particular, the group of eyes having normal values of high-order aberrations are more sensitive to translations than the one having higher values. Most of the results could be applied to other methods of aberration correction, such as refractive surgery or correction by means of intraocular lenses.
Article
To theoretically derive and empirically validate the relationship between the actual thick intraocular lens and the thin lens equivalent. Included in the study were 12 consecutive adult patients ranging in age from 54 to 84 years (mean +/- SD, 73.5 +/- 9.4 years) with best-corrected visual acuity better than 20/40 in each eye. Each patient had bilateral intraocular lens implants of the same style, placed in the same location (bag or sulcus) by the same surgeon. Preoperatively, axial length, keratometry, refraction, and vertex distance were measured. Postoperatively, keratometry, refraction, vertex distance, and the distance from the vertex of the cornea to the anterior vertex of the intraocular lens (AV(PC1)) were measured. Alternatively, the distance (AV(PC1)) was then back-calculated from the vergence formula used for intraocular lens power calculations. The average (+/-SD) of the absolute difference in the two methods was 0.23 +/- 0.18 mm, which would translate to approximately 0.46 diopters. There was no statistical difference between the measured and calculated values; the Pearson product-moment correlation coefficient from linear regression was 0.85 (r2 = .72, F = 56). The average intereye difference was -0.030 mm (SD, 0.141 mm; SEM, 0.043 mm) using the measurement method and +0.124 mm (SD, 0.412 mm; SEM, 0.124 mm) using the calculation method. The relationship between the actual thick intraocular lens and the thin lens equivalent has been determined theoretically and demonstrated empirically. This validation provides the manufacturer and surgeon additional confidence and utility for lens constants used in intraocular lens power calculations.
Essentials of biostatistics in public health
  • L M Sullivan
Sullivan LM. Essentials of biostatistics in public health. Burlington, CA: Jones & Bartlett Publishers; 2008. 156.
EA: effective addition; RA: regular astigmatism; IA: irregular astigmatism; SA: spherical aberration at 6 mm; µ: distance from pupil center to vertex normal; µ x : µ in horizontal cartesian coordinates; µ y : µ in vertical cartesian coordinates; d: intraocular lens centration from vertex normal
  • Km
Km: mean corneal power; AXL: axial length; ALP: actual lens position; EA: effective addition; RA: regular astigmatism; IA: irregular astigmatism; SA: spherical aberration at 6 mm; µ: distance from pupil center to vertex normal; µ x : µ in horizontal cartesian coordinates; µ y : µ in vertical cartesian coordinates; d: intraocular lens centration from vertex normal; d x : d in horizontal cartesian coordinates; d y : d in vertical cartesian coordinates; PP: photopic pupil diameter; MP: mesopic pupil diameter; SAM: spherical aberration computed for mesopic pupil.
Visual outcome and patient satisfaction after multifocal intraocular lens implantation: aspheric versus spherical design
  • De Vries
  • N E Webers
  • C A Verbakel
  • De Brabander
  • J Berendschot
  • T T Cheng
  • Y Y Doors
  • M Nuijts
De Vries NE, Webers CA, Verbakel F, De Brabander J, Berendschot TT, Cheng YY, Doors M, Nuijts RM. Visual outcome and patient satisfaction after multifocal intraocular lens implantation: aspheric versus spherical design. J Cataract Refract Surg. 2010;36(11):1897-904. doi:10.1016/j.jcrs.2010.05.030.
Dissatisfaction after implantation of multifocal intraocular lenses
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  • N E Webers
  • Cab Touwslager
  • Wrh Bauer
  • De Brabander
  • J Berendschot
  • T T Nuijts
De Vries NE, Webers CAB, Touwslager WRH, Bauer NJC, De Brabander J, Berendschot TT, Nuijts RMMA. Dissatisfaction after implantation of multifocal intraocular lenses. J Cataract Refract Surg. 2011;37(5):859-65. doi:10.1016/j.jcrs.2010.11.032.
Llovet-Osuna F. Comparison between mix-and-match implantation of bifocal intraocular lenses and bilateral implantation of trifocal intraocular lenses
  • R Bilbao-Calabuig
  • F González-López
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  • G Patel
Bilbao-Calabuig R, González-López F, Amparo F, Alvarez G, Patel SR, Llovet-Osuna F. Comparison between mix-and-match implantation of bifocal intraocular lenses and bilateral implantation of trifocal intraocular lenses. J Refract Surg. 2016;32(10):65963. doi:10.3928/1081597X-20160630-01.
Validation of a new clinical system for the fast measure of defocus curves with iPad
  • M Rodríguez-Vallejo
  • A Tauste
  • C Albarrán
  • I Basterra
  • D Piñero
  • J Fernández
Rodríguez-Vallejo M, Tauste A, Albarrán C, Basterra I, Piñero D, Fernández J Validation of a new clinical system for the fast measure of defocus curves with iPad. Paper presented at the XXXV Congress of the ESCRS, Lisbon, 7-11 October 2017. In 2017.
Refractive Analysis v.1.0.0. A Matlab toolbox for the analysis of refractive results in anterior segment surgery
  • M Rodríguez-Vallejo
Rodríguez-Vallejo M. Refractive Analysis v.1.0.0. A Matlab toolbox for the analysis of refractive results in anterior segment surgery. 2017 [accessed 2018 Jan 25].