Spherical aberration and depth of focus in eyes implanted with aspheric and spherical intraocular lenses: a prospective randomized study.
ABSTRACT To compare distance-corrected, near, and intermediate visual acuities as a measurement of depth of focus and spherical aberration of eyes implanted with aspheric and spherical intraocular lenses (IOLs).
Randomized prospective study.
One hundred twenty eyes of 60 patients with bilateral cataract implanted with 3 IOL models (AcrySof IQ, AcrySof SN60AT [Alcon Laboratories, Fort Worth, TX], and Sensar AR40 [Allergan Surgical, Irvine, CA]).
Pupil diameter was analyzed by using a Colvard pupillometer (OASIS Medical, Inc., Glendora, CA) under photopic, mesopic, and scotopic conditions. Distance (6 m), intermediate (1 m), and near (0.33 m) visual acuities were measured with distance correction in place 90 days after surgery. Wavefront analysis (LadarWave; Alcon Laboratories) was performed using 5-mm and measured photopic pupil diameter at 30 and 90 days after surgery.
To evaluate spherical aberration and depth of focus (by means of distance-corrected near and intermediate visual acuity) in patients implanted with aspheric and spherical IOLs.
Photopic pupil sizes in each group were similar at 30 days after surgery. At 90 days after surgery, mean logarithm of the minimum angle of resolution distance-corrected near visual acuity (+/-standard deviation [SD]) was 0.50+/-0.20 in the AcrySof IQ group, 0.38+/-0.17 in the AcrySof SN60AT group, and 0.45+/-0.16 in Sensar AR40 group. Mean spherical aberration values (+/-SD) were 0.03+/-0.05 microm in the AcrySof IQ group, 0.24+/-0.04 microm in the AcrySof SN60AT group, and 0.14+/-0.07 microm in the Sensar AR40 group. The AcrySof IQ group showed a statistically significant lower induction of spherical aberration and worse distance-corrected near visual acuity. The AcrySof SN60AT group showed statistically significant higher mean spherical aberration values and better distance-corrected near and intermediate visual acuity.
The reduction of total spherical aberration after aspheric IOL implantation may degrade distance-corrected near and intermediate visual acuity.
Article: Near Visual Acuity Following Hyperopic Photorefractive Keratectomy in a Presbyopic Age Group[show abstract] [hide abstract]
ABSTRACT: Purpose. To assess near visual acuity in a presbyopic age group following hyperopic photorefractive keratectomy (PRK). Setting. Private practice in Siena, Italy. Methods. In this retrospective single-surgeon comparative study, PRK with mitomycin C was performed to correct hyperopia using Bausch & Lomb 217z laser for 120 eyes of 60 patients in the presbyopic age group (mean spherical equivalent SE +2.38 D ± 0.71 D and mean age 52 ± 5.09). 120 eyes of 60 age-matched controls (mean age 54 ± 5.09) had their unaided near vision measured. Results. At 12 months mean SE was −0.10 D ± 0.27 D in the PRK group. Mean best corrected visual acuity (BSCVA) was 0.005 ± 0.022 log MAR; 2 eyes lost ≥0.1 log MAR. Mean uncorrected visual acuity was 0.04 ± 0.077 log MAR. Mean distance corrected near visual acuity (DCNVA) in the PRK group was J 3.73 ± 1.06. This was statistically better (P < 0.05) than the mean unaided near visual acuity in the control group J 4.07 ± 1.08. Conclusion. PRK was found to be safe, predictable, and an effective way of correcting hyperopia in this age group. It was also found to give better than expected near vision.ISRN Ophthalmology. 04/2012;
Article: Fellow-eye comparison of 2 aspheric microincision intraocular lenses and effect of asphericity on visual performance.[show abstract] [hide abstract]
ABSTRACT: To evaluate visual performance and aberrations with aspheric and spherically neutral microincision intraocular lenses (IOLs) and assess the influence of asphericity on visual performance, wavefront aberration, and depth of focus. St. Thomas' Hospital, London, United Kingdom. Clinical trial and cohort study. In the first study, patients with bilateral cataract were randomized to receive an aspheric Acri.Smart 36A IOL or a spherically neutral Akreos MI60 IOL in the first eye. The other IOL was implanted in the second eye within 3 weeks. Assessments at 3 months were 100% and 9% corrected distance visual acuity (CDVA) and distance-corrected near visual acuity (DCNVA). Aberrations and depth of focus were computed using iTrace software. In the second study, data from the other published study was combined to assess the visual performance, aberration, and depth of focus in groups of spherical, spherically neutral, and negatively aspheric (asphericity -0.17 μm) IOLs. In part 1, there was no difference in 100% or 9% CDVA, DCNVA, or depth of focus between the 2 microincision IOLs. Total spherical aberration was lower with the aspheric IOL. In part 2, the CDVA and DCNVA were not different between the spherical (n = 44), spherically neutral (n = 32), or aspheric (n = 76) IOLs. Total spherical (P<.01) and vertical coma aberrations decreased with increasing IOL asphericity (P<.01). Depth of focus (4.0 mm pupil) also decreased with increasing asphericity and was significant between the spherical IOL and aspheric IOLs. The DCNVA did not differ between groups. Asphericity of IOLs did not affect distance visual acuity. The difference in depth of focus was significant only between negatively aspheric and spherical IOLs. Asphericity differences up to 20 μm did not influence depth of focus.Journal of cataract and refractive surgery 02/2012; 38(4):625-32. · 2.75 Impact Factor
02/2012; , ISBN: 978-953-51-0230-4