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ABSTRACT: PURPOSE:: To evaluate the results of indocyanine green angiography (ICGA)-guided verteporfin (Visudyne®; Novartis Pharma, Switzerland) photodynamic therapy (PDT) with half-fluence rate in the treatment of chronic central serous chorioretinopathy. METHODS:: A retrospective review was conducted of 20 eyes of 19 consecutive patients with subfoveal fluid cause by chronic central serous chorioretinopathy with choroidal hyperpermeability on ICGA and symptoms of at least 6 months. ICGA-guided verteporfin (6 mg/m) PDT with half-fluence rate (25 J/cm) was performed. ICGA findings were classified as intense, intermediate, or minimal hyperfluorescence depending on the degree of choroidal hyperpermeability. The resolution of the subretinal fluid and recurrence rates were assessed in relation to the different degrees of choroidal hyperfluorescence. RESULTS:: Best-corrected visual acuity at baseline was 40 letters (±13; n = 20) according to the Early Treatment Diabetic Retinopathy Study chart. At 12 months after PDT, the mean best-corrected visual acuity improved to 44 letters (P < 0.01). Pretreatment central foveal thickness 325 μm and decreased by a mean of 103 μm at Month 12 control (P < 0.05). At Month 1 after PDT, subretinal fluid in spectral-domain optical coherence tomography was completely resolved in 100% of eyes regardless to their degree of choroidal hyperfluorescence. Two eyes of the intense hyperfluorescence group and 1 eye of the intermediate hyperfluorescence group developed recurrence of symptoms over 12 months and received another PDT with half-fluence rate within the 12-month control period. Treatment effect was not depending on the degree of choroidal hyperpermeability at baseline. No systemic side effects were observed during the 12-month follow-up. CONCLUSION:: ICGA-guided half-fluence PDT with verteporfin is effective in treating chronic symptomatic central serous chorioretinopathy with choroidal hyperpermeability in ICGA, resulting in both visual improvement and reduction of central foveal thickness.
Retina (Philadelphia, Pa.) 01/2013; · 2.93 Impact Factor
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ABSTRACT: A fully automated, robust vessel segmentation algorithm has been developed for choroidal OCT, employing multiscale 3D edge filtering and projection of "probability cones" to determine the vessel "core", even in the tomograms with low signal-to-noise ratio (SNR). Based on the ideal vessel response after registration and multiscale filtering, with computed depth related SNR, the vessel core estimate is dilated to quantify the full vessel diameter. As a consequence, various statistics can be computed using the 3D choroidal vessel information, such as ratios of inner (smaller) to outer (larger) choroidal vessels or the absolute/relative volume of choroid vessels. Choroidal vessel quantification can be displayed in various forms, focused and averaged within a special region of interest, or analyzed as the function of image depth. In this way, the proposed algorithm enables unique visualization of choroidal watershed zones, as well as the vessel size reduction when investigating the choroid from the sclera towards the retinal pigment epithelium (RPE). To the best of our knowledge, this is the first time that an automatic choroidal vessel segmentation algorithm is successfully applied to 1060 nm 3D OCT of healthy and diseased eyes.
Biomedical Optics Express 01/2013; 4(1):134-50. · 2.33 Impact Factor
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ABSTRACT: Purpose: Modern therapy of neovascular age-related macular degeneration consists in intravitreal injections of inhibitors of the vascular endothelial growth factor. An increasing number of these injections is required not only in monthly but also in as-needed treatment regimen. In this study, it should be examined whether an additional administered photodynamic therapy (PDT) can considerably reduce the number of injection. Methods: In this prospective, randomized study carried out in three large hospitals of Vienna eyes with neovascular age-related macula degeneration were included. Patients were randomized to either Ranibizumab monotherapy or combined standard fluence PDT and Ranibizumab therapy. All patients received a loading dose of three intravitreal Ranibizumab injections and were thereafter treated in an as-needed regimen based on distance acuity and retinal thickness values. In the combined treatment group, PDT was administered 1 day after the first Ranibizumab injection. Results: Fifty-one patients were randomized, 44 were finally included (four screening failures and three withdrawals). Twenty-four patients were assigned to the monotherapy and 20 patients to the combined treatment group. Fewer injections were required in the combined treatment group (4.7 versus 6.3). Overall the patients lost 0.5 letters; in the combined treatment group, the patients lost mean 7.1 letters; in the monotherapy group, they gained mean 5.1 letters. Retinal thickness decreased significantly in both groups. Conclusion: A significant reduction of the number of required intravitreal injections could be achieved by the additional PDT treatment, but was accompanied by a worse functional outcome in this group.
Acta ophthalmologica 12/2012; · 2.44 Impact Factor
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ABSTRACT: BACKGROUND: To evaluate the effect of half-fluence rate indocyanine green angiography (ICGA)-guided verteporfin photodynamic therapy (PDT) on macular sensitivity (MS) in eyes with acute symptomatic central serous chorioretinopathy (CSC). METHODS: Single-center consecutive case series by retrospective chart review. Sixteen eyes of 16 patients with acute CSC of 3 months duration or less, treated with half-fluence (25 mJ/cm(2)) ICGA-guided verteporfin PDT were reviewed. At baseline and after 1, 3, and 6 months, all patients underwent MS testing of the central 20 °, MS testing of the retinal area covered by the PDT laser spot (MSLS), and evaluation of fixation stability (FS) for the central two degrees with the MP-1 microperimeter (Nidek, Vigonza, Italy). RESULTS: Macular sensitivity improved from 16.4 ± 3.0 dB at baseline (n = 16) to 18.2 ± 2.4 dB (p < 0.001) at 1 month (n = 16). At the 3-month (n = 13) and 6-month (n = 12) follow-up, MS stabilized at 19.5 ± 0.9 dB (p = 0.21) and 19.0 ± 1.3 dB (p = 0.74), without changes when compared to respective precedent follow-up. Mean MSLS improved from 12.9 ± 5.4 dB at baseline to 16.4 ± 4.9 dB (p < 0.001) after 1 month. At the 3- and 6-month follow-up, MSLS was 19.1 ± 1.2 dB (p = 0.1) and 18.9 ± 1.9 dB (p = 0.8) respectively. Mean FS at the central 2 ° was 78.8 ± 30.4 % before treatment and 81.8 ± 29.5 % (p = 0.7), 81.9 ± 27.5 % (p = 0.7) and 83.6 ± 17.1 % (p = 0.5) respectively 1, 3 and 6 months after treatment. CONCLUSION: Half-fluence (25 mJ/cm(2)) PDT significantly increased mean MS of central 20 ° and mean MSLS, in eyes with acute symptomatic CSC. Fixation stability was stable at baseline and throughout 6 months of follow-up.
Albrecht von Graæes Archiv für Ophthalmologie 08/2012; · 2.17 Impact Factor
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ABSTRACT: : To evaluate the results of indocyanine green angiography-guided verteporfin (Visudyne; Novartis Pharma AG, Switzerland) photodynamic therapy with half-fluence rate in the treatment of acute symptomatic central serous chorioretinopathy.
: A retrospective review over 12 months was performed of 19 consecutive patients with subfoveal fluid because of acute symptomatic central serous chorioretinopathy proved by spectral-domain optical coherence tomography and fluorescein angiography, treated with indocyanine green angiography-guided verteporfin (6 mg/m) photodynamic therapy with half-fluence rate (25 J/cm). Acute symptomatic central serous chorioretinopathy was defined as first episode of symptoms and duration of symptoms before treatment of ≤12 weeks.
: Best-corrected visual acuity at baseline was 47 letters (±10; n = 19) according to the Early Treatment Diabetic Retinopathy Study chart. At 12 months after photodynamic therapy, the mean best-corrected visual acuity improved to 56 letters (P = 0.003).Pretreatment central foveal thickness was 406 μm and decreased by a mean of 163 μm at Month 12 control (P < 0.001). At Month 1 after photodynamic therapy, subretinal fluid in spectral-domain optical coherence tomography was completely resolved in all 19 patients. None of the patients developed any recurrence of symptoms over 12 months. No ocular or systemic side effects were observed during 12 months follow-up.
: Indocyanine green angiography-guided half-fluence photodynamic therapy with verteporfin is effective in treating acute symptomatic central serous chorioretinopathy, resulting in visual improvement and complete resolution of exudative macular detachment.
Retina (Philadelphia, Pa.) 03/2012; 32(10):2014-9. · 2.93 Impact Factor
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Edward Z Zhang,
Boris Povazay,
Jan Laufer,
Aneesh Alex,
Bernd Hofer,
Barbara Pedley, Carl Glittenberg,
Bradley Treeby,
Ben Cox,
Paul Beard,
Wolfgang Drexler
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ABSTRACT: A noninvasive, multimodal photoacoustic and optical coherence tomography (PAT/OCT) scanner for three-dimensional in vivo (3D) skin imaging is described. The system employs an integrated, all optical detection scheme for both modalities in backward mode utilizing a shared 2D optical scanner with a field-of-view of ~13 × 13 mm(2). The photoacoustic waves were detected using a Fabry Perot polymer film ultrasound sensor placed on the surface of the skin. The sensor is transparent in the spectral range 590-1200 nm. This permits the photoacoustic excitation beam (670-680 nm) and the OCT probe beam (1050 nm) to be transmitted through the sensor head and into the underlying tissue thus providing a backward mode imaging configuration. The respective OCT and PAT axial resolutions were 8 and 20 µm and the lateral resolutions were 18 and 50-100 µm. The system provides greater penetration depth than previous combined PA/OCT devices due to the longer wavelength of the OCT beam (1050 nm rather than 829-870 nm) and by operating in the tomographic rather than the optical resolution mode of photoacoustic imaging. Three-dimensional in vivo images of the vasculature and the surrounding tissue micro-morphology in murine and human skin were acquired. These studies demonstrated the complementary contrast and tissue information provided by each modality for high-resolution 3D imaging of vascular structures to depths of up to 5 mm. Potential applications include characterizing skin conditions such as tumors, vascular lesions, soft tissue damage such as burns and wounds, inflammatory conditions such as dermatitis and other superficial tissue abnormalities.
Biomedical Optics Express 08/2011; 2(8):2202-15. · 2.33 Impact Factor
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ABSTRACT: To evaluate the outcome after two types of retinal pigment epithelium (RPE) transplantation techniques.
Fourteen consecutive patients with advanced exudative age-related macular degeneration (AMD) were randomly assigned to RPE-choroid sheet transplantation (group 1) or RPE cell-suspension transplantation (group 2). Outcome measures included best corrected distance and near visual acuity (BCVA), complication and recurrence rates, autofluorescence (AF), angiography, and time-domain and spectral-domain optical coherence tomography (TD- and SD-OCT).
A gain of three or more lines in BCVA at 24 months was found in two patients in group 1 and in one patient in group 2, whereas a loss of vision of three or more lines occurred in one patient in each group. Revision surgery for proliferative vitreoretinopathy was required in one patient in group 1. Epiretinal membranes developed in two patients in group 1 and in one patient in group 2. No recurrence occurred in this series. AF showed hyperfluorescence coincident with the graft in group 1, and hyper- and hypofluorescence in irregular patterns in group 2. Revascularisation of the graft was present in all patients in group 1, and a normal choroidal vasculature in the area of RPE atrophy in all patients in group 2. OCT showed a decrease in retinal thickness in all patients, with an improved visualisation of inter- and intralaminar structures with SD-OCT.
The anatomical and functional outcome after both RPE transplantation techniques was comparable. Intrastructural irregularities of the sheet assessed using SD-OCT might explain the rather limited visual gain in otherwise successful sheet transplants. Clinical Trial Registration NCT00401713.
The British journal of ophthalmology 03/2011; 95(3):370-5. · 2.92 Impact Factor
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ABSTRACT: A novel non-invasive in vivo multimodal optical coherence tomography (OCT)/photoacoustic tomography (PAT) imaging system capable of obtaining structural and functional information simultaneously has been demonstrated in skin. A 1060 nm OCT system acquiring 47k depth-scans/s with textasciitilde 7 μm axial and textasciitilde 20 μm transverse resolutions has been incorporated into a backward-mode PA system based on a planar, optically-transparent Fabry-Perot interferometer (FPI) sensor. In this study, the excitation wavelength was set to 670 nm and a focused laser beam at 1550 nm was used as the sensor interrogation beam. OCT and PAT images were obtained sequentially and the coregistered images were combined to form the final 3D image. OCT/PAT images obtained in vivo from the skin of a hairless mouse and human palmar skin demonstrated the ability of this multimodal imaging system to provide complementary structural and functional information from deeper depths with increased contrast.
Proceedings of SPIE. 02/2011; 7889(1):788916-788916-6.
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ABSTRACT: To assess reproducibility and compare raster scanning protocols of Cirrus high-definition optical coherence tomography (Carl Zeiss Meditec, Dublin, CA).
Five hundred and twenty-eight computed tomography scans were performed in 17 healthy subjects. Four sessions were performed at each visit including two 200 × 200 and two 512 × 128 macular cube scans per session. The examined eye, observer, and order of scanning protocols in-between each session were randomly chosen. Reproducibility was described with intraclass correlation coefficients, coefficients of variance, intervisit, interrater, intersession intra-, and intersubject standard deviations.
Intraclass correlation coefficients ranged from 80.4% to 97.8% and the coefficients of variance from 0.7% to 2.3% for retinal volume and retinal thickness measurements. Intersubject, intervisit, interrater, intersession, and intrasubject standard deviations ranged from 0 μm to 18.54 μm. Differences in retinal thickness between protocols were small (range 3.55 ± 1.95 μm to 0.81 ± 0.59 μm) but significant for the central (P < 0.0001), the outer superior (P = 0.0036), temporal (P = 0.0026), and nasal subfield (P < 0.0001). Average difference of retinal volume between protocols was 0.05 ± 0.04 mm (P = 0.0001).
Both raster scanning protocols of the Cirrus optical coherence tomography showed excellent reproducibility of retinal thickness and volume measures. Significant differences between protocols for retinal thickness in four macula thickness map subfields and for retinal volume were found.
Retina (Philadelphia, Pa.) 01/2011; 31(1):41-7. · 2.93 Impact Factor
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ABSTRACT: The role of changes at the vitreoretinal interface and vitreomacular traction forces in pathogenesis, and the course of exudative age-related macular degeneration (AMD) need further exploration. This study examines the localisation of adhesion and the direction of traction lines in eyes with exudative AMD.
The cubes 512×128 of Cirrus optical coherence tomography (OCT) and volume scans of Spectralis OCT were reviewed in a consecutive series of patients presenting between December 2008 and March 2009 with vitreomacular adhesion in exudative AMD.
30 eyes of 25 patients with exudative AMD and vitreomacular adhesion were studied. 50% had type III lesions, 46.7% occult and 3.3% predominantly classic lesions. The localisation of the adhesion corresponded in 100% with the area of the neovascularisation (CNV), in 73.3% traction directed towards the CNV and in 83.3% towards the optic disc could be noted. Spectral domain OCT and 3D visualisation enabled clearer localisation of vitreomacular adhesion and definition of resulting traction lines.
There is a high prevalence of type III lesions within eyes with vitreomacular adhesions, and complete correspondence between the location of the adhesion and the CNV. There is also a high incidence of vitreopapillary adhesion in these cases, suggesting a possible role in pathogenesis.
The British journal of ophthalmology 01/2011; 95(10):1415-8. · 2.92 Impact Factor
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ABSTRACT: To evaluate the feasibility of intrasurgical spectral-domain optical coherence tomography in a pilot study.
Using a Carl Zeiss Meditec Cirrus HD-OCT system adapted to the optical pathway of a Zeiss OPMI VISU 200 surgical microscope, 512 × 128 macular cube scans were performed during various steps of microsurgical procedures in 25 cases. The acquired volume data were postprocessed and visualized using a ray-traced three-dimensional display system.
The surgical procedures included pars plana vitrectomies for epiretinal membranes (n = 8), macular holes (n = 4), primary rhegmatogenous retinal detachment (n = 1), proliferative diabetic retinopathy (n = 3), silicone oil removal (n = 2), and cataract surgery only (n = 7). It was possible to acquire intraretinal scans with sufficient quality from all patients. Decisions for additional membrane peeling, knowledge about the behavior of the macular hole and the foveal depression during and after membrane removal, information about clinically invisible fluid accumulation under silicone oil or in a clinically diagnosed "macula-on" retinal detachment, and the condition of the fovea immediately after cataract removal could be gained.
Intrasurgical spectral-domain optical coherence tomography evaluation is feasible using the tested system and may positively influence surgical decisions and techniques resulting in an improved patient outcome.
Retina (Philadelphia, Pa.) 01/2011; 31(7):1332-6. · 2.93 Impact Factor
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ABSTRACT: To assess prognostic factors in epiretinal membrane (ERM) surgery using spectral-domain (SD) optical coherence tomography (OCT).
Prospective, interventional case series.
Forty-one patients.
Patients with a diagnosis of ERM were examined with spectral-domain and time-domain (TD) OCT before and after surgery.
Main outcome measures were functional results and predefined OCT patterns. Cofactors analyzed were the type of ERM, the duration and grading of subjective metamorphopsia, simultaneous cataract surgery, the type of dyes used, the duration of surgery, gender, and age. A multivariate regression analysis was performed.
Thirty-nine patients (95%) showed an improved or stable best-corrected distance visual acuity (DVA) at 3 months, whereas 36 patients (88%) showed an improved or stable best-corrected near visual acuity (NVA) at 3 months. Significant correlations (P>0.4) were found between the course of central retinal thickness (CRT) assessed using SD OCT and TD OCT (P<0.02). No clinically relevant correlations (P<0.3) were seen between CRT and VA (P>0.1). Baseline DVA and NVA were found to be significant prognostic values for the postoperative decrease in CRT in both OCT systems (P<0.04) as well as for the visual outcomes (P<0.007) at 3 months. In addition, the integrity of the junction between the photoreceptor inner segment and outer segment (IS/OS) significantly influenced the visual outcomes at 3 months (P<0.038). The baseline profile of the internal limiting membrane (ILM) significantly influenced the NVA at 3 months (P<0.009), whereas the postoperative foveal contour significantly influenced the DVA at 3 months (P<0.025). The type of ERM, subjective metamorphopsia, simultaneous cataract surgery, the type of dyes used, the duration of surgery, gender, or age had no significant influence on patient outcome (P>0.05). Compared with TD OCT, SD OCT allowed for a more precise differentiation between the ERM and the retinal surface and for a better evaluation of the IS/OS line.
Besides the baseline VA, the integrity of the IS/OS line, better visualized by SD OCT, can be used to predict the functional outcomes after surgery. Additionally, analyzing the ILM profile and the foveal contour may help to understand limited visual outcomes after surgery.
The author(s) have no proprietary or commercial interest in any materials discussed in this article.
Ophthalmology 04/2010; 117(4):798-805. · 5.45 Impact Factor
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Alex Aneesh,
Boris Považay,
Bernd Hofer,
Edward Z Zhang,
Catherine Kendall,
Jan Laufer,
Sergei Popov, Carl Glittenberg,
Susanne Binder,
Nicholas Stone,
Paul C Beard,
Wolfgang Drexler
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ABSTRACT: High speed, three-dimensional optical coherence tomography (3D OCT) at 800nm, 1060nm and 1300nm with approximately 4μm, 7μm and 6μm axial and less than 15μm transverse resolution is demonstrated to investigate the optimum wavelength region for in vivo human skin imaging in terms of contrast, dynamic range and penetration depth. 3D OCT at 1300nm provides deeper penetration, while images obtained at 800nm were better in terms of contrast and speckle noise. 1060nm region was a compromise between 800nm and 1300nm in terms of penetration depth and image contrast. Optimizing sensitivity, penetration and contrast enabled unprecedented visualization of micro-structural morphology underneath the glabrous skin, hairy skin and in scar tissue. Higher contrast obtained at 800 nm appears to be critical in the in vitro tumor study. A multimodal approach combining OCT and PA helped to obtain morphological as well as vascular information from deeper regions of skin.
Proceedings of SPIE. 02/2010; 7554(1):75540V-75540V-6.
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American journal of ophthalmology 01/2010; 149(1):172-3. · 3.83 Impact Factor
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ABSTRACT: To report the reproducibility of macular pigment optical density (MPOD) values assessed with heterochromatic flicker photometry (HFP) in healthy individuals.
Twenty-four volunteers from our department underwent MPOD testing of both eyes by flicker photometry on three separate occasions. To test reproducibility of MPOD, the coefficient of variance was calculated separately for right and left eyes. In addition, we investigated MPOD averages of right and left eyes and interocular correlations (Pearson's r) at every visit.
The mean MPODs at the first visit were 0.61 +/- 0.24 and 0.72 +/- 0.27 in right and left eyes, respectively. Mean values of 0.58 +/- 0.29 and 0.60 +/- 0.21 (second visit) and 0.62 +/- 0.27 and 0.63 +/- 0.24 (third visit) were assessed for right and left eyes, respectively. Differences of the mean values between eyes were not significant. Correlations were weak at visits one and two (r = 0.49, p < 0.014 and r = 0.43, p < 0.038, respectively) and moderate at visit three (r = 0.58, p < 0.003). The coefficients of variance were 36.1% and 23% for right and left eyes, respectively.
Our mean MPODs are higher and the interocular correlations weaker compared to the literature. The coefficient of variance in both eyes is high and does not imply good reproducibility of obtained MPOD values.
Acta ophthalmologica 01/2009; 88(2):207-11. · 2.44 Impact Factor
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ABSTRACT: The aim of this study was to examine whether the presence of retinal angiomatous proliferation (RAP) is a prognostic factor in subretinal surgery with transplantation of a suspension of autologous retinal pigment epithelial (RPE) cells.
Eyes that had been followed for at least 12 months after subretinal surgery were reviewed retrospectively and assigned to group 1 (presence of RAP) or group 2 (lesions without RAP). Main outcome measures were logMAR distance acuity and lesion size at 12 months.
A total of 68 eyes of 68 patients were included; 28 were assigned to group 1 and 40 to group 2. A total of 43% of patients were male and 57% were female. Their mean age was 77.8 years. Mean distance acuity was 1.02 logMAR at baseline and 1.06 logMAR at month 12. Mean lesion size was 27.9 mm(2) at baseline and 29.9 mm2 at month 12. The differences between the groups were not significant.
The presence of RAP did not significantly influence the outcome after subretinal surgery with transplantation of autologous RPE cells. Other than age, preoperative lesion size and distance acuity were the only predictive factors for postoperative results.
Acta ophthalmologica 09/2008; 86(5):504-9. · 2.44 Impact Factor
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ABSTRACT: To compare the state of the posterior vitreous in exudative age-related macular degeneration (AMD) with eyes with nonexudative AMD and controls.
Prospective, observational case series.
B-scan ultrasonography and optical coherence tomography (OCT) were performed in 163 eyes from 82 subjects older than 55 years, 50 eyes with exudative AMD, 57 with nonexudative AMD, and 56 control eyes. Main outcome measures were the number of eyes with complete posterior vitreous detachment (PVD) by ultrasound and the number of eyes with central vitreomacular adhesion by OCT.
By ultrasonography, 17 (34.0%) of 50 eyes with exudative AMD had PVD as compared with 41 (71.9%) of 57 eyes with nonexudative AMD (P = .00002) and 34 (60.7%) of 56 controls (P = .017). OCT detected persistent central vitreoretinal adhesion surrounded by a detached posterior vitreous cortex in 18 (36%) of 50 eyes with exudative AMD, significantly higher than in nonexudative AMD (4/57 [7%]; P < .0001) and in controls (6/56 [10%]; P = .002).
Persistent attachment of the posterior vitreous cortex to the macula may be another risk factor for the development of exudative AMD via vitreoretinal traction inducing chronic low-grade inflammation, by maintaining macular exposure to cytokines or free radicals in the vitreous gel, or by interfering in transvitreous oxygenation and nutrition of the macula. Inducing PVD may provide prophylactic benefit against exudative AMD.
American Journal of Ophthalmology 12/2007; 144(5):741-746. · 4.22 Impact Factor
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ABSTRACT: The retinal pigment epithelium (RPE) maintains retinal function as the metabolic gatekeeper between photoreceptors (PRs) and the choriocapillaries. The RPE and Bruch's membrane (BM) suffer cumulative damage over lifetime, which is thought to induce age-related macular degeneration (AMD) in susceptible individuals. Unlike palliative pharmacologic treatments, replacement of the RPE has a curative potential for AMD. This article reviews mechanisms leading to RPE dysfunction in aging and AMD, laboratory studies on RPE transplantation, and surgical techniques used in AMD patients. Future strategies using ex vivo steps prior to transplantation, BM prosthetics, and stem cell applications are discussed. The functional peculiarity of the macular region, epigenetic phenomena leading to an age-related shift in protein expression, along with the accumulation of lipofuscin may affect the metabolism in the central RPE. Thickening of BM with age decreases its hydraulic conductivity. Drusen are deposits of extracellular material and formed in part by activation of the alternative complement pathway in individuals carrying a mutant allele of complement factor H. AMD likely represents an umbrella term for a disease entity with multifactorial etiology and manifestations. Presently, a slow progressing (dry) non-neovascular atrophic form and a rapidly blinding neovascular (wet) form are discerned. No therapy is currently available for the former, while RPE transplantation and promising (albeit non-causal) anti-angiogenic therapies are available for the latter. The potential of RPE transplantation was demonstrated in animal models. Rejection of allogeneic homologous transplants in patients focused further studies on autologous sources. In vitro studies elucidated cell adhesion and wound healing mechanisms on aged human BM. Currently, autologous RPE, harvested from the midperiphery, is being transplanted as a cell suspension or a patch of RPE and choroid in AMD patients. These techniques have been evaluated from several groups. Autologous RPE transplants may have the disadvantage of carrying the same genetic information that may have led to AMD manifestation. An intermittent culturing step would allow for in vitro therapy of the RPE, its rejuvenation and prosthesis of BM to improve the success RPE transplants. Recent advances in stem cell biology when combined with lessons learned from studies of RPE transplantation are intriguing future therapeutic modalities for AMD patients.
Progress in Retinal and Eye Research 10/2007; 26(5):516-54. · 9.45 Impact Factor
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ABSTRACT: The aim of this investigation was to evaluate prognostic factors influencing the short-term prognosis of occult choroidal neovascularization (CNV).
A consecutive series of 107 untreated occult CNV in 101 patients were evaluated in terms of the effect of their initial lesion characteristics, as determined with fluorescein angiography (FA), indocyanine green angiography (ICG-A) and optical coherence tomography (OCT), on the change in distance acuity, lesion size and retinal thickness over 1-3 months. Descriptive statistics, the Pearson Correlation Coefficient and a multiple linear regression analysis were applied to treat the data.
A total of 107 eyes (101 patients) were examined. The study cohort consisted of 35 males and 66 females, with a mean age of 77.6 years. During the 3-month study period the mean distance acuity decreased from 67.0 to 63.2 letters; the mean size of the lesion increased from 16.1 to 18.4 mm(2); the mean maximum retinal thickness increased from 374.5 to 387.5 mum. Of the lesions, 59.8% included pigment epithelial detachments (serous or fibrovascular) and 29.9% retinal angiomatous proliferation. A better distance acuity at both visits for the entire study population correlated significantly with smaller lesions, as determined by FA and ICG-A (p < 0.0001), and a lower maximum retinal thickness, as determined by the OCT (p < 0.0001).
A small and statistically insignificant change in distance acuity, lesion size and retinal thickness occurred over the 3 months of the study period. This reduced the ability of the study to examine the effect of baseline findings on outcome. Only two factors - the presence of a RAP lesion or the presence of CNV in the other eye - significantly and adversely affected the distance visual acuity at follow-up.
Albrecht von Graæes Archiv für Ophthalmologie 03/2007; 245(3):376-84. · 2.17 Impact Factor
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ABSTRACT: To examine whether the encouraging functional results one year after photodynamic therapy (PDT) can be maintained up to three years.
Prospective interventional case series.
Highly myopic eyes that had been treated with PDT for subfoveal choroidal neovascularization and had been observed at least 36 months were included. Distance acuity (Early Treatment of Diabetic Retinopathy charts), reading acuity (Jaeger charts), 10-degree static threshold perimetry, fluorescein angiography, and optical coherence tomography were performed. The main outcome measures were the differences of the values among the baseline and the month 12 and the month 36 examinations.
Twenty eyes of 18 patients were included: 15 patients were female, and 3 patients were male. The average age was 64 years (range, 36 to 85 years). The mean distance acuity was 43 letters at baseline and 53 letters after 12 months and after 36 months. The mean reading acuity changed from mean J10.8 to mean J8.1 after 12 months and to mean J9.85 after 3 years. The mean defect decreased from mean 13.5 dB at baseline to mean 12.5 dB after 12 months and mean 11.2 dB after 36 months. The maximum retinal thickness decreased from mean 360 mum at baseline to mean 259 mum after one year and mean 238 mum after 36 months.
Distance acuity and central visual field showed stabilization after the month 12 examination up to the month 36 examination. The reading acuity decreased between the month 12 and the month 36 examinations, which might be related to an increase of retinal atrophy.
American Journal of Ophthalmology 10/2005; 140(3):416-25. · 4.22 Impact Factor
