Retinal pigment epithelial characteristics in eyes with neovascular age-related macular degeneration : Long-term retinal changes under anti-vascular endothelial growth factor treatment.

PURPOSE: The aim of this study was to assess retinal pigment epithelial (RPE) and retinal structural changes in eyes with neovascular age-related macular degeneration (AMD) treated with anti-vascular endothelial growth factor (anti-VEGF) during long-term follow-up and to evaluate morphological markers potentially influencing prognosis. METHODS: A total of 18 eyes of 18 patients with neovascular AMD were examined subsequent to completion of the Avastin Versus Lucentis in Age Related Macular Degeneration (MANTA) study following a mean period of 84 months (range 69-93 months). After receiving a loading dose of 3 intravitreal anti-VEGF injections subsequent to baseline of the MANTA study, patients were treated as needed (pro re nata, PRN). Functional and morphological changes were assessed, the latter using spectral domain optical coherence tomography (SD-OCT). RESULTS: Retinal/RPE atrophy generally increased significantly during follow-up compared to baseline (fibrosis 28% vs. 89%, p = 0.0001, geographic atrophy, GA 0% vs. 67%, p = 0.0002, RPE porosity 61% vs. 100%, p = 0.009) whereas regenerative alterations tendentially increased until 3 months and then subsequently declined until the last visit (RPE thickening 28% vs. 11%, p = 0.22 and intraretinal hyperreflective foci 89% vs. 78%, p = 0.39). CONCLUSION: Atrophic alterations of the retina and RPE are progressive and may partly be induced by anti-VEGF. Morphological findings may aid in the identification of prognostic markers in the progression of neovascular AMD. This could lead to a more targeted education of affected patients.

Clinical evaluation of neovascular and non-neovascular chronic central serous chorioretinopathy (CSC) diagnosed by swept source optical coherence tomography angiography (SS OCTA).

PURPOSE: To evaluate the clinical characteristics of eyes with chronic central serous chorioretinopathy based on swept source optical coherence tomography angiography (SS OCTA). METHODS: Twenty-nine eyes presenting with chronic central serous chorioretinopathy (CSC) were examined with the Topcon SS OCTA, using the DRI optical coherence tomography (OCT) Triton machine, and were classified as neovascular or non-neovascular CSC depending on whether a vascular pattern was detected in the outer retina on OCT angiogram. The two groups were compared based on the following clinical findings: best corrected distance and reading visual acuity (BCDVA, best corrected reading acuity (BCRA)), rate of subretinal fluid, intraretinal fluid, hyperreflective flat pigment epithelial detachment (PED), and serous PED. RESULTS: Of 29 eyes with chronic CSC, 10 (34.5%) showed a neovascular pattern, suggesting neovascular CSC, in the outer retina of SS OCTA. Eyes with neovascular CSC showed a significantly worse initial and final BCDVA, with a mean value of 0.39 ± 0.20 logMAR (Snellen equivalent 20/49) and 0.33 ± 0.36 logMAR (Snellen equivalent 20/43), compared to eyes with non-neovascular CSC with a mean value of 0.16 ± 0.15 logMAR (Snellen equivalent 20/29) and 0.04 ± 0.11 logMAR (Snellen equivalent 20/22) (p < 0.05), respectively. Final mean BCRA was 0.14 ± 0.20 logRAD for non-neovascular CSC compared to 0.34 ± 0.28 logRAD (p = 0.031) for neovascular CSC. The mean time between the first and final visits was 3 years for both groups. The mean anti-VEGF injection rate was 6.4 for neovascular CSC and 2.9 for non-neovascular CSC, whereas 26.3% of non-neovascular CSC eyes had an additional half fluence photodynamic therapy (PDT). CONCLUSION: SS OCTA provides a promising CNV detection rate, secondary to chronic CSC, in a clinical setting. Neovascular CSC is associated with a worse outcome in terms of visual and reading acuity compared to non-neovascular CSC.

A novel method to evaluate quality of care from the perspective of cataract patients.

PURPOSE: To evaluate quality of care from patient's perspective following cataract surgery using a novel questionnaire and to assess validity of the survey in context with the identification of lacks in quality of care. METHODS: Assessment of quality of care in 150 patients (150 eyes) who underwent cataract surgery in an Austrian clinical setting based on a novel "Quality of Care from Patient's perspective following Cataract Surgery" (QCPCS)-questionnaire including 10 subjective, 10 objective and 7 general health care criteria. Quality of care was graded according to importance (range: 1 = not important to 4 = extremely important) and frequency of occurrence (range: 1 = never to 4 = often, 0 = not applicable). Quality-impact indices (QI-respective grading by patient/4) were assessed. RESULTS: Mean performance score was 3.84 (SD = 0.42, range: 1-4). Mean QI was 0.89 for subjective, 0.90 for objective and 0.96 for general health care criteria (p = 0.29). All-over skewness and coefficient of variation were -2.65 and 5.85 respectively. Internal consistency was high (Cronbach's α = 0.75) confirming causal taxonomy of disease-specific and generic items. CONCLUSION: A valid new method to reliably and holistically evaluate patient's satisfaction related to cataract surgery including a broad range of patient needs is presented, suitable to assess potential lacks in quality of health care in daily ophthalmological clinical practice.

Assessment of long-term intraocular lens (IOL) decentration and tilt in eyes with pseudoexfoliation syndrome (PES) following cataract surgery.

BACKGROUND: To evaluate long-term intraocular lens (IOL) decentration and tilt in eyes with pseudoexfoliation syndrome (PES) following cataract surgery using Visante anterior segment OCT and iTrace Visual Function Analyzer. METHODS: Sixty-four eyes following cataract surgery from 2009 to 2012 were included, 34 eyes had PES and 30 eyes did not show PES. A standard phacoemulsification procedure followed by IOL implantation was performed and patients were followed 4-6 years after surgery (mean = 69 months). Best-corrected visual acuity (BCVA), capsulorhexis size, and intraocular pressure (IOP) were measured. IOL decentration and IOL tilt were evaluated using Visante Omni anterior segment OCT (Carl Zeiss Jena GmBH, Germany). The iTrace VFA (Visual Function Analyzer, Hoya surgical optics) was used to measure corneal, internal, and total optical aberrations. RESULTS: Measurements with iTrace showed that horizontal coma was significantly different between PES and control eyes (p = 0.037). Horizontal as well as vertical tilt showed a significant difference between PES and control eyes (p = 0.035 and p = 0.039). Tilt correlated with capsulorhexis size in PES patients (p = 0.011). This indicates a forward tilt of the superior edge of the IOL in eyes with PES. CONCLUSIONS: Patients affected by PES seem to have a higher risk for long-term complications and changes in visual perception due to IOL tilt and decentration after cataract surgery.

Treatment of Diabetic Macular Edema with Intravitreal Antivascular Endothelial Growth Factor and Prompt versus Deferred Focal Laser during Long-Term Follow-Up and Identification of Prognostic Retinal Markers.

PURPOSE: Long-term follow-up of patients with diabetic macular edema (DME) treated with intravitreal antivascular endothelial growth factor (anti-VEGF) combined focal laser and identification of prognostic morphological characteristics. METHODS: Prospective clinical trial (50 treatment-naive eyes) with DME randomized 1 : 1 receiving intravitreal ranibizumab (0.5 mg/0.05 ml) and prompt grid laser compared with ranibizumab and deferred laser. Morphological characteristics potentially relevant for prognosis were assessed at baseline, month 6, month 9, and years 1, 2, 3, 4, and 5 of follow-up. RESULTS: Although functional results were slightly higher in the prompt group at week 12 (0.5; 20/40 Snellen (SD = 0.04, 0.3 logMAR) versus 0.4; 20/50 Snellen (SD = 0.04, logMAR: 0.4), p=0.4) and month 9 (prompt group: 0.5; 20/40 Snellen (SD = 0.03, 0.3 logMAR) versus deferred group: 0.4; 20/50 Snellen (SD = 0.04, 0.4 logMAR), p=0.4), these were statistically insignificant. There was no significant benefit regarding functionality during long-term follow-up in the prompt group compared to the deferred group. BCVA in the eyes with clusters of hyperreflective foci in the central macular region was inferior compared with the eyes without these alterations at year 5 (0.39; 20/50 Snellen, (SD = 0.25, 0.4 logMAR) versus 0.63; 20/80 Snellen (SD = 0.22, 0.2 logMAR), p < 0.01). CONCLUSION: Grid laser and ranibizumab therapy are effective in DME management during the long-term follow-up. Intraretinal hyperreflective material in SD-OCT is negatively related to BCVA.

Polarisation-sensitive OCT is useful for evaluating retinal pigment epithelial lesions in patients with neovascular AMD.

BACKGROUND/AIMS: To examine the reproducibility of lesion dimensions of the retinal pigment epithelium (RPE) in neovascular age-related macular degeneration (AMD) with polarisation-sensitive optical coherence tomography (PS-OCT), specifically imaging the RPE. METHODS: Twenty-six patients (28 eyes) with neovascular AMD were included in this study, and examined by a PS-OCT prototype. Each patient was scanned five times at a 1-day visit. The PS-OCT B-scan located closest to the macular centre presenting with RPE atrophy was identified, and the longitudinal diameter of the lesion was quantified manually using AutoCAD 2008. This procedure was followed for the identical B-scan position in all five scans per eye and patient. Reproducibility of qualitative changes in PS-OCT was evaluated. Interobserver variability was assessed. Results were compared with intensity-based spectral-domain OCT (SD-OCT) imaging. RESULTS: Mean variability of all atrophy lesion dimensions was 0.10 mm (SD±=0.06 mm). Coefficient of variation (SD±/mean) was 0.06 on average (SD±=0.03). Interobserver variability assessment showed a mean difference of 0.02 mm across all patients regarding RPE lesion size evaluation (paired t test: p=0.38). Spearman correlation coefficient was r=0.98, p<0.001. Results revealed a good overall reproducibility of ∼90%. PS-OCT specifically detected the RPE in all eyes compared with conventional intensity-based SD-OCT that was not capable to clearly identify RPE atrophy in 25 eyes (89.3%, p<0.01). CONCLUSIONS: PS-OCT offers good reproducibility of RPE atrophy assessment in neovascular AMD, and may be suitable for precise RPE evaluation in clinical practice. PS-OCT unambiguously identifies RPE changes in choroidal neovascularisation compared with intensity-based SD-OCT that does not identify the RPE status reliably.

Progression of retinal pigment epithelial atrophy in antiangiogenic therapy of neovascular age-related macular degeneration.

PURPOSE: To monitor retinal pigment epithelial (RPE) atrophy progression during antiangiogenic therapy of neovascular age-related macular degeneration (AMD) over 2 years using polarization-sensitive optical coherence tomography (OCT). DESIGN: Prospective interventional case series. METHODS: setting: Clinical practice. STUDY POPULATION: Thirty patients (31 eyes) with treatment-naïve neovascular AMD. OBSERVATION PROCEDURES: Standard intravitreal therapy (0.5 mg ranibizumab) was administered monthly during the first year and pro re nata (PRN; as-needed) during the second year. Spectral-domain (SD) OCT and polarization-sensitive OCT (selectively imaging the RPE) examinations were performed at baseline and at 1, 3, 6, 12, and 24 months using a standardized protocol. RPE-related changes were evaluated using a semi-automated polarization-sensitive OCT segmentation algorithm and correlated with SD OCT and fundus autofluorescence (FAF) findings. MAIN OUTCOME MEASURES: RPE response, geographic atrophy (GA) progression. RESULTS: Atrophic RPE changes included RPE thinning, RPE porosity, focal RPE atrophy, and development of GA. Early RPE loss (ie, RPE porosity, focal atrophy) increased progressively during initial monthly treatment and remained stable during subsequent PRN-based therapy. GA developed in 61% of eyes at month 24. Mean GA area increased from 0.77 mm(2) at 12 months to 1.10 mm(2) (standard deviation = 1.09 mm(2)) at 24 months. Reactive accumulation of RPE-related material at the lesion borders increased until month 3 and subsequently decreased. CONCLUSIONS: Progressive RPE atrophy and GA developed in the majority of eyes. RPE migration signifies certain RPE plasticity. Polarization-sensitive OCT specifically images RPE-related changes in neovascular AMD, contrary to conventional imaging methods. Polarization-sensitive OCT allows for precisely monitoring the sequence of RPE-related morphologic changes.

Retinal pigment epithelium findings in patients with albinism using wide-field polarization-sensitive optical coherence tomography.

PURPOSE: To investigate pigmentation characteristics of the retinal pigment epithelium (RPE) in patients with albinism using wide-field polarization-sensitive optical coherence tomography compared with intensity-based spectral domain optical coherence tomography and fundus autofluorescence imaging. METHODS: Five patients (10 eyes) with previously genetically diagnosed albinism and 5 healthy control subjects (10 eyes) were imaged by a wide-field polarization-sensitive optical coherence tomography system (scan angle: 40 × 40° on the retina), sensitive to melanin contained in the RPE, based on the polarization state of backscattered light. Conventional intensity-based spectral domain optical coherence tomography and fundus autofluorescence examinations were performed. Retinal pigment epithelium-pigmentation was analyzed qualitatively and quantitatively based on depolarization assessed by polarization-sensitive optical coherence tomography. RESULTS: This study revealed strong evidence of polarization-sensitive optical coherence tomography to specifically image melanin in the RPE. Depolarization of light backscattered by the RPE in patients with albinism was reduced compared with normal subjects. Heterogeneous RPE-specific depolarization characteristics were observed in patients with albinism. Reduction of depolarization observed in the light backscattered by the RPE in patients with albinism corresponds to expected decrease of RPE pigmentation. The degree of depigmentation of the RPE is possibly associated with visual acuity. Findings suggest that different albinism genotypes result in heterogeneous levels of RPE pigmentation. CONCLUSION: Polarization-sensitive optical coherence tomography showed a heterogeneous appearance of RPE pigmentation in patients with albinism depending on different genotypes.

Lesion size detection in geographic atrophy by polarization-sensitive optical coherence tomography and correlation to conventional imaging techniques.

PURPOSE: To investigate the reproducibility of automated lesion size detection in patients with geographic atrophy (GA) using polarization-sensitive spectral-domain optical coherence tomography (PS-OCT) and to compare findings with scanning laser ophthalmoscopy (SLO), fundus autofluorescence (FAF), and intensity-based spectral-domain OCT (SD-OCT). METHODS: Twenty-nine eyes of 22 patients with GA were examined by PS-OCT, selectively identifying the retinal pigment epithelium (RPE). A novel segmentation algorithm was applied, automatically detecting and quantifying areas of RPE atrophy. The reproducibility of the algorithm was assessed, and lesion sizes were correlated with manually delineated SLO, FAF, and intensity-based SD-OCT images to validate the clinical applicability of PS-OCT in GA evaluation. RESULTS: Mean GA lesion size of all patients was 5.28 mm(2) (SD: 4.92) in PS-OCT. Mean variability of individual repeatability measurements was 0.83 mm(2) (minimum: 0.05; maximum: 3.65). Mean coefficient of variation was 0.07 (min: 0.01; max: 0.19). Mean GA area in SLO (Spectralis OCT) was 5.15 mm(2) (SD: 4.72) and 2.5% smaller than in PS-OCT (P = 0.9, Pearson correlation coefficient = 0.98, P < 0.01). Mean GA area in intensity-based SD-OCT pseudo-SLO images (Cirrus OCT) was 5.14 mm(2) (SD: 4.67) and 2.7% smaller than in PS-OCT (P = 0.9, Pearson correlation coefficient = 0.98, P < 0.01). Mean GA area of all eyes measured 5.41 mm(2) (SD: 4.75) in FAF, deviating by 2.4% from PS-OCT results (P = 0.89, Pearson correlation coefficient = 0.99, P < 0.01). CONCLUSIONS: PS-OCT demonstrated high reproducibility of GA lesion size determination. Results correlated well with SLO, FAF, and intensity-based SD-OCT fundus imaging. PS-OCT may therefore be a valuable and specific imaging modality for automated GA lesion size determination in scientific studies and clinical practice.

Large-field high-speed polarization sensitive spectral domain OCT and its applications in ophthalmology.

We present a novel spectral domain polarization sensitive OCT system (PS-OCT) that operates at an A-scan rate of 70 kHz and supports scan angles of up to 40° × 40°. The high-speed imaging allows the acquisition of up to 1024 × 250 A-scans per 3D scan, which, together with the large field of view, considerably increases the informative value of the images. To demonstrate the excellent performance of the new PS-OCT system, we imaged several healthy volunteers and patients with various diseases such as glaucoma, AMD, Stargardt's disease, and albinism. The results are compared with clinically established methods such as scanning laser polarimetry and autofluorescence.

Polarization sensitive optical coherence tomography of melanin provides intrinsic contrast based on depolarization.

Polarization sensitive optical coherence tomography (PS-OCT) is a functional extension of OCT. In addition to imaging based on tissue reflectivity, PS-OCT also enables depth-resolved mapping of sample polarization properties such as phase-retardation, birefringent axis orientation, Stokes vectors, and degree of polarization uniformity (DOPU). In this study, PS-OCT was used to investigate the polarization properties of melanin. In-vitro measurements in samples with varying melanin concentrations revealed polarization scrambling, i.e. depolarization of backscattered light. Polarization scrambling in the PS-OCT images was more pronounced for higher melanin concentrations and correlated with the concentration of the melanin granules in the phantoms. Moreover, in-vivo PS-OCT was performed in the retinas of normal subjects and individuals with albinism. Unlike in the normal eye, polarization scrambling in the retinal pigment epithelium (RPE) was less pronounced or even not observable in PS-OCT images of albinos. These results indicate that the depolarizing appearance of pigmented structures like, for instance, the RPE is likely to be caused by the melanin granules contained in these cells.

Morphologic characteristics of idiopathic juxtafoveal telangiectasia using spectral-domain and polarization-sensitive optical coherence tomography.

PURPOSE: Idiopathic juxtafoveal telangiectasia (IJT) is characteristically associated with pigmentary changes. Polarization-sensitive spectral-domain optical coherence tomography (PS-SD-OCT) enables imaging of the retinal pigment epithelium (RPE) and similar melanin-containing structures based on specific polarization properties. This study examined IJT with the latest-generation SD-OCT and PS-SD-OCT, identifying pathophysiologically relevant characteristics of the retinal layers and RPE. METHODS: Twenty-two eyes of 12 patients with IJT were examined by PS-SD-OCT, with special focus on RPE detection and segmentation. Furthermore, SD-OCT technology (Cirrus, Spectralis, and 3D-OCT-1000) was applied. Characteristics of the retinal layers and RPE were evaluated. A classification system based on OCT characteristics of IJT was suggested. RESULTS: Polarization-sensitive spectral-domain optical coherence tomography together with SD-OCT identified characteristic patterns of IJT, used to classify eyes into three distinct groups. Group 1 (5 eyes) revealed discrete alterations in the inner retinal layers; group 2 (12 eyes) showed irregularities of the junction between the inner and outer photoreceptor segments with outer retinal atrophy but an intact RPE. Group 3 (5 eyes) revealed RPE irregularities and loss in addition to intraretinal alterations and photoreceptor abnormalities. CONCLUSION: This study described characteristic morphologic changes in IJT based on PS-SD-OCT and SD-OCT. Morphologic changes were classified, possibly leading to an OCT-based grading scheme. The intensity images of SD-OCT verified intraretinal and photoreceptor irregularities in great detail, whereas PS-SD-OCT additionally showed RPE alterations.

Performance of automated drusen detection by polarization-sensitive optical coherence tomography.

PURPOSE: To estimate the potential of polarization-sensitive optical coherence tomography (PS-OCT) for quantitative assessment of drusen in patients with early age-related macular degeneration (AMD). METHODS: Fifteen eyes from 13 patients presenting drusen consistent with Age-Related Eye Disease Study classifications (grades 2 and 3) were examined ophthalmoscopically, followed by fundus photography, autofluorescence imaging, and three-dimensional scanning using a PS-OCT. For the automated evaluation of drusen location, area, and volume, a novel segmentation algorithm was developed based on the polarization scrambling characteristics of the retinal pigment epithelium (RPE) and applied to each complete data set. Subsequently, the drusen in each individual B-scan were identified by two independent expert graders. Concordance between manual and automated segmentation results was analyzed. Errors in the automated segmentation performance were classified as nonsignificant, moderate, or severe. RESULTS. In all, 2355 individual drusen, with a mean of 157 drusen per eye, were analyzed. Of drusen seen in the individual B-scans, 91.4% were detected manually by both expert graders. The automated segmentation algorithm identified 96.5% of all drusen without significant error. The mean difference in manual and automated drusen area (mean, 4.65 mm(2)) was 0.150. The number of detected drusen was significantly higher with automated than that with manual segmentation. PS-OCT segmentation was generally superior to fundus photography (P < 0.001). Particularly in nondetected drusen, a large variability in drusen morphology was noted. CONCLUSIONS: Automated drusen detection based on PS-OCT technology allows a fast and accurate determination of drusen location, number, and total area.

Evaluation of segmentation procedures using spectral domain optical coherence tomography in exudative age-related macular degeneration.

PURPOSE: The purpose of this study was to evaluate standardized automated segmentation procedures of spectral domain optical coherence tomography (SD-OCT) in imaging of age-related macular degeneration. METHODS: Twenty-nine eyes of 29 patients with neovascular age-related macular degeneration were included. Three groups were assigned, according to the predominant localization of extravasated fluid in the intra-, subretinal, and subretinal pigment epithelium (RPE) compartment. Automated segmentation procedures were evaluated in B scans of 512 × 128 × 1024 and 200 × 200 × 1024 scan patterns using SD-OCT (Cirrus). Alignment errors at the internal limiting membrane, actual RPE, and extrapolation of the physiologic RPE (RPE fit) were graded using a standardized classification system. RESULTS: The rate of severe alignment failures was 56% and 41% for the 512 × 128 and the 200 × 200 raster pattern, respectively. Internal limiting membrane and actual RPE boundaries were most correctly delineated in the 200 × 200 raster pattern. Retinal pigment epithelium fit alignment was generally poor in 50% of scans. Retinal thickness values defined by internal limiting membrane and actual RPE segmentation were 90% accurate and not compromised by RPE fit misalignment. Subretinal fluid was demarcated most reliably. Alignment errors may occur together with a large spectrum of morphologic alterations. CONCLUSION: Automated algorithms of SD-OCT demonstrate a substantial rate of alignment failures in the assessment of exudative age-related macular degeneration pathologies, which are usually associated with misinterpretation of boundaries at the (sub) RPE level.

Quantification of the therapeutic response of intraretinal, subretinal, and subpigment epithelial compartments in exudative AMD during anti-VEGF therapy.

PURPOSE: To analyze the functional and morphologic effects of different ranibizumab treatment regimens on retinal and subretinal as well as sub-RPE compartments in neovascular age-related macular degeneration (nAMD) using spectral-domain optical coherence tomography (SD-OCT) and manual segmentation software. METHODS: Twenty-seven eyes of 27 patients with nAMD were examined over a 12-month period. Two treatment arms received either monthly or quarterly administered intravitreal ranibizumab. Intraretinal, subretinal, and sub-RPE volume equivalents were delineated using manual segmentation software over a defined series of B-scans obtained by SD-OCT. The mean area in pixels was calculated for each compartment at each time interval. RESULTS: SD-OCT and manual segmentation allowed for exact identification of intraretinal, subretinal and sub-RPE compartments and their responses to different treatment regimens. The loading dose demonstrated a corresponding treatment effect on all anatomic parameters. In contrast to the sub-RPE compartment, intraretinal fluid accumulation and subretinal fluid accumulation (SRFA) demonstrated an immediate response to ranibizumab therapy. The overall plasticity of the morphologic response declined over time. In general, SRFA demonstrated greater sensitivity for therapeutic effects and was more frequently associated with recurrent disease. CONCLUSIONS: An exact quantification of fluid in different anatomic compartments based on SD-OCT imaging, using appropriate segmentation software systems, may be useful to determine optimal treatment and retreatment parameters and explains the lack of correlation of best-corrected visual acuity and conventional OCT values.

Performance of OCT segmentation procedures to assess morphology and extension in geographic atrophy.

PURPOSE: Investigating segmentation procedures and morphological findings in time domain (TD) and current spectral domain (SD) optical coherence tomography (OCT) devices in patients with geographic atrophy (GA). METHODS: Fifty eyes of 46 patients with GA secondary to AMD and 15 control eyes were examined in this prospective noninterventional comparative case series. All patients underwent Stratus (model 3000), Cirrus (Carl Zeiss Meditec), Spectralis (Spectralis HRA+OCT; Heidelberg Engineering) and 3D-OCT-1000 (Topcon). Automated segmentation analyses were compared. An overlay of scanning laser ophthalmoscope (SLO) and three-dimensional retinal thickness (RT) maps were used to investigate whether areas of retinal thinning correspond to areas of retinal pigment epithelium (RPE) atrophy. RESULTS: Geographic atrophy areas identified in SLO scans were significantly larger than areas of retinal thinning in RT maps. No convincing topographic correlation could be found between areas of retinal thinning and actual GA size as identified in SLO and fundus photography. Spectralis OCT showed significantly more mild and severe segmentation errors than 3D and Cirrus OCT. CONCLUSION: This study showed substantial limitations in identifying zones of GA reliably when using automatic segmentation procedures in current SD-OCT devices. This limitation should be addressed to visualize and document RPE loss realistically in a frequent disease like GA.

Performance of drusen detection by spectral-domain optical coherence tomography.

PURPOSE: To evaluate the performance of automated analyses integrated in three spectral-domain optical coherence tomography (SD-OCT) devices to identify drusen in eyes with early (i.e., nonatrophic and nonneovascular) age-related macular degeneration (AMD). METHODS: Twelve eyes of 12 AMD patients, classified as AREDS 2 and 3 and having a mean count of 113 drusen were examined with three clinical SD-OCT devices (Cirrus [Carl Zeiss Meditec, Dublin CA], 3DOCT-1000 [Topcon, Tokyo, Japan], and Spectralis [Heidelberg Engineering, GmbH, Heidelberg, Germany]) and five different scan patterns. After standard automated segmentation of the RPE was performed, every druse in each B-scan was identified and graded by two independent expert graders. Errors in the segmentation performance were classified as negligible, moderate, or severe. Correlations were based on the diameter and height of the druse and its automated segmentation. The overall drusen pattern identified by experts' detailed delineation was plotted with a custom-made computer program to compare automated to manual identification outcomes. RESULTS: A total of 1356 drusen were analyzed. The automated segmentation of the retinal pigment epithelium (RPE) by Cirrus made significantly fewer errors in detecting drusen than did the 3DOCT-1000 (P < 0.001). The Cirrus 200 × 200 scan pattern detected 30% of the drusen with negligible errors. Spectralis did not offer a true RPE segmentation. The drusen counts by expert graders were significantly higher in the scans than in the standard fundus photographs (P < 0.05). CONCLUSIONS: SD-OCT imaging proved an excellent performance in visualizing drusen-related RPE disease. However, the available automated segmentation algorithms showed distinct limitations to reliable identification of the amount of drusen, particularly smaller drusen, and the actual size.

Imaging of the retinal pigment epithelium in age-related macular degeneration using polarization-sensitive optical coherence tomography.

Purpose. Spectral-domain optical coherence tomography (SD-OCT) provides new insights into the understanding of age-related macular degeneration (AMD) but limited information on the nature of hyperreflective tissue at the level of the retinal pigment epithelium. Therefore, polarization-sensitive (PS) SD-OCT was used to identify and characterize typical RPE findings in AMD. Methods. Forty-four eyes of 44 patients with AMD were included in this prospective case series representing the entire AMD spectrum from drusen (n = 11), geographic atrophy (GA; n = 11), neovascular AMD (nAMD; n = 11) to fibrotic scars (n = 11). Imaging systems were used for comparative imaging. A PS-SD-OCT instrument was developed that was capable of recording intensity and polarization parameters simultaneously during a single scan. Results. In drusen, PS-SD-OCT identified a continuous RPE layer with focal elevations. Discrete RPE atrophy (RA) could be observed in two patients. In GA, the extension of the RA was significantly larger. Residual RPE islands could be detected within the atrophic zone. PS-SD-OCT identified multiple foci of RPE loss in patients with nAMD and allowed recognition of advanced RPE disease associated with choroidal neovascularization. Wide areas of RA containing residual spots of intact retinal pigment epithelium could be identified in fibrotic scars. Conclusions. PS-SD-OCT provided precise identification of retinal pigment epithelium in AMD. Recognition of these disease-specific RA patterns in dry and wet forms of AMD is of particular relevance to identify the status and progression of RPE disease and may help to better estimate the functional prognosis of AMD.

Association of retinal sensitivity and morphology during antiangiogenic treatment of retinal vein occlusion over one year.

PURPOSE: Evaluation of the association between functional and anatomic retinal changes during anti-vascular endothelial growth factor (VEGF) therapy with bevacizumab (Avastin) in patients with cystoid macular edema secondary to retinal vein occlusion (RVO) using microperimetry and spectral domain optical coherence tomography (SD-OCT). DESIGN: Prospective, uncontrolled study (EUDRACT NR-2005-003288-21). PARTICIPANTS: Twenty-eight patients with cystoid macular edema secondary to RVO. METHODS: Patients initially received 3 consecutive intravitreal injections of 1.25 mg bevacizumab at 4-week intervals. Further treatment was based on morphologic (OCT) and functional best-corrected visual acuity (BCVA) findings. During the 1-year follow-up, a rigorous standardized evaluation was performed monthly. Macular function was documented by microperimetry (Nidek, MP1 Microperimeter) and BCVA based on the Early Treatment in Diabetic Retinopathy Study (ETDRS). Morphologic parameters included central retinal thickness (CRT) as measured by conventional OCT (Stratus), and central subfield thickness (CST), mean retinal thickness (MRT), and retinal volume (RV) measured by SD-OCT. MAIN OUTCOME MEASURES: Imaging of retinal morphology using OCT and SD-OCT and evaluation of retinal function assessed with microperimetry and ETDRS charts during 12 months of anti-VEGF treatment. RESULTS: Within 6 months, the mean area of absolute scotoma was reduced from 21.4% of the central visual field to 6.4% and remained at this level until month 12 (7.4%). Mean BCVA improved from 51 to 66 letters on ETDRS charts. The CRT, CST, and MRT decreased significantly (P<0.002) and remained stable during the follow-up. The RV values did not improve significantly under therapy. Statistical analysis using a linear effects model revealed significant associations between the functional and morphologic outcomes, most notably between BCVA, macular sensitivity, CRT (Stratus OCT), CST, and MRT (Cirrus OCT) values. CONCLUSIONS: Central retinal morphology, especially CRT and CST measured by conventional and SD-OCT, and retinal function improved significantly during treatment of RVO with a flexible dosing regimen of intravitreal bevacizumab. Functional (central visual acuity and visual field) and morphologic parameters (retinal thickness) were significantly related. These associations highlight the value of OCT imaging for assessing this disease entity.