Effect of anti-VEGF treatment on choroidal thickness over time in patients with neovascular age-related macular degeneration.

PURPOSE: To evaluate change in subfoveal choroidal thickness (SCT) as measured by spectral-domain optical coherence tomography (SD-OCT) in patients with neovascular age-related macular degeneration (NVAMD) undergoing anti-vascular endothelial growth factor (VEGF) therapy. METHODS: Patients with a diagnosis of NVAMD were retrospectively reviewed to identify those who had at least 12 months of follow-up. The SCT was manually measured from Bruch membrane to the choroid-sclera junction at baseline and last follow-up. Only cases in which the choroid was fully visible were included in quantitative analyses. The SCT measurements were correlated with other characteristics including number and duration of treatments. RESULTS: Sixty eyes of 47 patients with a follow-up of 23.8 months (SD 7.3) met study inclusion criteria, and 49 eyes of 40 patients received anti-VEGF treatment. Mean age was 83.7 years, and 52% were female. Treated eyes received a mean of 7.8 (SD 7.3) intravitreal anti-VEGF injections. The SCT at baseline was 126.7 µm (SD 50.6) for untreated and 136.2 µm (SD 57.6) for treated eyes. The SCT showed a decrease over time in both groups, with a mean rate of reduction of 6.0 µm (p<0.0002) in treated eyes and 3.6 µm (p = 0.3741) in untreated eyes. However, the change in SCT did not differ between the groups (p = 0.5113), and did not correlate with the number of re-treatments (p = 0.552), visual acuity at baseline (p = 0.618), or change in visual acuity over time (p = 0.429). CONCLUSIONS: Although choroidal thickness decreased over time in eyes with NVAMD, anti-VEGF therapy did not appear to accelerate or otherwise alter this decline.

Relationship between visual acuity and spectral domain optical coherence tomography retinal parameters in neovascular age-related macular degeneration.

PURPOSE: Relationship between spectral domain optical coherence tomography (SD-OCT) and visual acuity (VA) in neovascular age-related macular degeneration (NVAMD). PROCEDURES: VA and SD-OCTs of 64 treatment-naive eyes with NVAMD were retrospectively collected at baseline and 1 year (n = 30). Retinal and subretinal spaces were manually analyzed. Volume and thickness measurements were correlated with VA. RESULTS: At baseline, lower VA correlated with increased volume of subretinal hyperreflective material (R = 0.4, p < 0.001) and with decreased volume of the photoreceptor layer (PRL, R = -0.4, p < 0.01). At 1 year, lower VA correlated with decreased volume of the retina (R = -0.7, p < 0.001), outer nuclear layer (R = -0.6, p < 0.05) and PRL (R = -0.7, p < 0.001). Decrease in VA after 1 year correlated with a decrease in PRL (R = 0.4, p < 0.05). CONCLUSIONS: Quantitative analysis of SD-OCT revealed correlations between VA and retinal and subretinal morphological changes in NVAMD. MESSAGE: Atrophy of the outer retina is an important correlate for lower VA in NVAMD.

Atypical outer retinal fluid accumulation in choroidal neovascularization: a novel OCT finding.

BACKGROUND AND OBJECTIVE: To report a novel optical coherence tomography (OCT) finding in choroidal neovascularization (CNV). PATIENTS AND METHODS: The authors identified seven eyes with CNV demonstrating the atypical pattern of fluid accumulation within the outer retina on OCT. Patient demographics, best corrected visual acuity and spectral-domain OCT (SD-OCT) images were collected for all available follow-up visits. Volume and area of the fluid were measured on SD-OCT. Microperimetry was performed in one case. RESULTS: The outer retinal fluid was located between the external limiting membrane (ELM) and the outer photoreceptor band on SD-OCT. Within this area, the outer segments of the photoreceptors were visualized as a continuous band, which appeared to split from the retina, dropping down toward the retinal pigment epithelium (mean area: 2.53 ± 1.23 mm(2); mean volume: 0.19 ± 0.20 mm(3)). All cases demonstrated the finding only at one time point during follow-up. Recovery of the outer retina and retinal function could be detected. CONCLUSION: Atypical intraretinal fluid accumulation externally to the ELM may be detected on SD-OCT in eyes with CNV. This finding may be transient and may not preclude subsequent improvement in visual function. The frequency of the presumed photoreceptor delamination and its full clinical significance remain to be defined.

The retinal disease screening study: retrospective comparison of nonmydriatic fundus photography and three-dimensional optical coherence tomography for detection of retinal irregularities.

PURPOSE: To determine the sensitivity of three-dimensional optical coherence tomography (3D-OCT) versus single field nonmydriatic fundus photography (FP) for detection of a variety of retinal abnormalities. METHODS: Images from consecutive patients in a retina clinic undergoing simultaneous 3D-OCT (512 × 128) and single, foveal nonmydriatic 45° color fundus imaging with 3D-OCT-1000 in a 4 month-period were retrospectively collected. Findings from each modality were graded independently by two graders as present, questionable, or absent. Irregularities were separated into three categories for intermodality comparisons: epiretinal, retinal/subretinal, and RPE/choroidal irregularities. The approximate location of findings in relation to the 3D-OCT field was noted as in field and out of field. Findings from both modalities were combined to form the gold standard for comparison for each modality. RESULTS: Five hundred and one sets of 3D-OCT scans and fundus images of 395 eyes of 223 patients were found in the study period, of which, 474 unique visits were included. Ninety-six percent of the scans had abnormal findings. Twenty-six fundus images (5.5%) were ungradable. 3D-OCT identified some abnormality in 25/26 (96.2%) of the ungradable fundus images. For overall detection of a variety of retinal irregularities or irregularity of each category (epiretinal, intraretinal, or RPE/choroidal irregularity), 3D-OCT was found to be more sensitive than that of nonmydriatic color fundus images. When single specific feature was speculated, 3D-OCT demonstrated various detection abilities: higher than FP for abnormal retinal thickness (or intraretinal hyporeflective features); similar as FP for RPE atrophy; however, lower for pigment migration (or intraretinal hemorrhage). CONCLUSIONS: In this study, sensitivities of 3D-OCT were higher than nonmydriatic fundus images for overall detection of retinal abnormalities or irregularities in each category. 3D-OCT demonstrated good ability to detect most features; however, with limitation to intraretinal hemorrhage and pigment migration. It is likely that OCT will be added to photography screening for chorioretinal diseases in the near future.

Different phenotypes of the appearance of the outer plexiform layer on optical coherence tomography.

PURPOSE: To present a selected case series of different phenotypes of the normal outer plexiform layer (OPL) visualized by optical coherence tomography (OCT). METHODS: Five cases were selected to represent the spectrum of appearances of the OPL in this case series. Categorical descriptions of each manifestation were then developed. Additional SD-OCT scans were obtained from a normal volunteer to further support the hypothesis. RESULTS: The inner one-third of the OPL typically appears hyperreflective on OCT, while the outer two-thirds (Henle fiber layer) may have a more varied appearance. Six different phenotypes of Henle fiber layer reflectivity were noted in this series, and classified as: bright, columnar, dentate, delimited, indistinct, and dark. The brightness of the Henle fiber layer appears to depend on the geometric angle between the OCT light beam and the axonal fibers in this portion of the OPL. This angle appears to be a function of the natural orientation of the Henle fiber layer tissue (θN), the existence of subretinal pathology that alters the angle of the neurosensory retina (θ(P)), and the tilt angle of the tissue on the B-scan (θ(T)) due to decentered OCT acquisition. CONCLUSIONS: Since accurate interpretation of the OPL/ONL boundary is of vital importance to study the thickness of ONL, location of cystoid lesions, hyperreflective crescents over drusen, et al., our case series may aid better understanding of the OPL appearance in SD-OCT. In the absence of clear delineation, it may be most correct to refer to indistinct OPL and ONL together as the photoreceptor nuclear axonal complex (PNAC).

Evaluation of the axial location of cystoid spaces in retinal vein occlusion using optical coherence tomography.

PURPOSE: To analyze the axial distribution of intraretinal cystoid changes in patients with retinal vein occlusion (RVO), incorporating a new hypothesis about the optical coherence tomographic boundary between the outer nuclear layer and the outer plexiform layer. METHODS: Data were collected from patients with RVO who underwent spectral domain coherence tomography imaging. For each image set, certified graders evaluated each retinal layer for cystoid macular edema, defined as hyporeflective intraretinal cystoid spaces. Subretinal fluid, if present, was also noted. RESULTS: Forty-eight eyes were evaluated (24 branch RVO, 18 central RVO, 6 hemiretinal vein occlusion). Cystoid macular edema was present in 30.8% of eyes in outer nuclear layer, 77.9 % in outer plexiform layer, 77.9 % in inner nuclear layer, 36.9 % in inner plexiform layer, 48.8 % in ganglion cell layer, and 4.9% in nerve fiber layer. Subretinal fluid was assessed as present in 23.8% of patients. The presence of subretinal fluid correlated most strongly with cystoid changes in the outer nuclear layer (r = 0.514, P = 0.001) but was not significantly correlated with these changes in the superficial retina. CONCLUSION: Use of spectral domain coherence tomography allows precise characterization of the axial location of cystoid spaces in RVO and highlights the frequency of fluid accumulation in the outer plexiform layer and inner nuclear layer. Using updated definitions, cystoid macular edema seems to occur less frequently in the outer nuclear layer, but when it does so, it is often associated with subretinal fluid. Future longitudinal studies, documenting the axial progression of such changes, and their response to treatment, may be of clinical relevance as pharmacotherapeutic options evolve.

Juxtapapillary pigment epithelium detachment observed in asymptomatic participants using optical coherence tomography.

PURPOSE: To use three-dimensional optical coherence tomography (3D-OCT) to assess the prevalence of juxtapapillary retinal pigment epithelial detachments (jPED) in an asymptomatic population. METHODS: Asymptomatic participants (i.e., family members of patients) were prospectively recruited over a 6-month period. Each subject completed a questionnaire prior to the acquisition of two undilated 45° fundus images and two undilated raster 3D-OCT scans (512 × 128) covering the macula and optic nerve from each eye using 3D-OCT-1000. Fundus images were graded for the presence of peripapillary atrophy (PPA), peripapillary pigment (PPP), drusen in the macula, and drusen elsewhere, whereas 3D-OCT scans were assessed for the presence of jPED, drusen in the macula, and drusen elsewhere. RESULTS: In all, 276 eyes from 138 participants were evaluated. Mean participant age was 37.6 years (range: 18-74 years; SD: 15.5 years). In all, 87 jPEDs were detected in 26.1% (36/138) of asymptomatic participants (25 bilateral and 11 unilateral) or 17.0% (47/276) of asymptomatic eyes (23 in the right eye and 24 in the left). The maximum height of jPED was 198.3 ± 53.8 (range: 101.8-376.0) µm. The minimum distance of jPED to the border of optic nerve head (OPN) was 2.6 ± 11.1 (range: 0-61.9) µm. The occurrence of jPEDs or drusen elsewhere by subjects increased statistically with increasing age (P < 0.001, respectively). CONCLUSIONS: In this study, definite jPEDs were observed by OCT in asymptomatic participants, which were not seen with fundus photography. jPEDs were seen more commonly with increasing age, although it is not known whether these lesions represent deposition of drusen-like material or aborted choroidal neovascularization adjacent to the natural break in Bruch's membrane at the optic disc.

The retinal disease screening study: prospective comparison of nonmydriatic fundus photography and optical coherence tomography for detection of retinal irregularities.

PURPOSE: To compare the sensitivity of volume scanning with optical coherence tomography (OCT) to nonmydriatic color fundus photography (FP) for the detection of retinal irregularities in asymptomatic populations. METHODS: Asymptomatic subjects without known ocular disease were recruited over a 6-month period. For each eye, two undilated 45° fundus images and four undilated volume OCT image sets covering the macula and optic nerve were obtained. Color images were evaluated for irregularities both inside and outside the area covered by OCT. OCT image sets were evaluated for internal limiting membrane irregularities, abnormal retinal thickness, hyper/hyporeflective features, and photoreceptor/retinal pigment epithelium (RPE) irregularities. Detection sensitivities were compared and false-negative cases were analyzed. RESULTS: A total of 284 eyes (144 subjects) were included, with a mean age of 38.1 years (range 18-77). Among 253 eyes (135 subjects) with gradable images from both FP and OCTs, the detection sensitivities for OCT were higher (96.2% infield and 85.7% in full field) than for FP (19.9% infield and 43.8% in full field) for all irregularities evaluated in the study (including epiretinal irregularities, abnormal retinal thickness, intraretinal hyperreflective/hyporeflective features, and photoreceptor/RPE irregularities). Overall, the presence of definite irregularities on either fundus imaging or OCT by eye in this asymptomatic population was 42.6% (121/284), with 39.4% (112/284) of eyes having RPE irregularities such as drusen. CONCLUSIONS: For detection of a variety of retinal irregularities evaluated in the current study, volume OCT scanning was more sensitive than nonmydriatic retinal photography in our asymptomatic individuals. OCT detected clinically relevant disease features, such as subretinal fluid, that were missed by FP, and had a lower ungradable image rate. It is likely that OCT will be added to photography screening in the near future for chorioretinal disease.

Impact of scanning density on spectral domain optical coherence tomography assessments in neovascular age-related macular degeneration.

PURPOSE: To determine the effect of optical coherence tomography (OCT) B-scan density on the qualitative assessment of neovascular age-related macular degeneration (AMD). METHODS: Data were collected from 59 patients imaged with Topcon 3D OCT-1000 (128 B-scans × 512 A-scans). Custom software was used to generate less dense subsets of scans: 1/16 (eight B-scans), 1/8 (16 B-scans), 1/4 (32 B-scans) and 1/2 (64 B-scans). At each B-scan density, scans were assessed for cystoid spaces, subretinal fluid (SRF), subretinal tissue (SRT) and pigment epithelium detachment (PED). For each sampling density, sensitivity, specificity and predictive values were calculated using the full volume scan (128 B-scans) as the reference standard. RESULTS: For cystoid spaces, the detection sensitivity was 76.3% at 1/16 density; this rose to 89.5% with a 1/4 density. For SRF, the detection sensitivity was 75.0% at a 1/16 density; this increased to 91.1% with 1/4 density. For PED, even at the lowest sampling density (1/16) the detection sensitivity was 86.4%; this rose to 94.9% at 1/4 density. For SRT, detection sensitivity at a 1/16 density was 64.7% and only rose above 90% with the densest sampling subset (1/2). CONCLUSIONS: Use of scanning protocols with reduced sampling densities resulted in decreased detection of key features of neovascular AMD; despite this, a sampling density reduced to 1/4 appeared to allow accurate assessment for most features. Current management of neovascular AMD is dependent on qualitative assessment of OCT images; with the recent proliferation of OCT systems, optimization and standardization of scanning protocols may be of value.

Assessment of differential pharmacodynamic effects using optical coherence tomography in neovascular age-related macular degeneration.

PURPOSE: To use novel OCT parameters in assessing the differential pharmacodynamic effects of bevacizumab (Avastin; Genentech, South San Francisco, CA), pegaptanib (Macugen; OSI Pharmaceuticals, New York, NY), and verteporfin photodynamic therapy (PDT; Novartis, Basel, Switzerland) in a recently completed phase III/IV clinical trial. METHODS: Data from 122 patients participating in the Avastin (Bevacizumab) for Choroidal Neovascularization (ABC) trial, were evaluated. OCT scans were analyzed with custom software. Changes in the volume of the neurosensory retina, amount of subretinal fluid (SRF), pigment epithelium detachment (PED), and subretinal tissue (SRT), were calculated over the 54-week trial period. RESULTS: Reductions in retinal edema were more than twice as great from bevacizumab as from pegaptanib (-0.82 mm³ vs. -0.31 mm³), whereas SRF reduction was more than three times greater (-0.54 mm³ vs. -0.15 mm³. Both bevacizumab and pegaptanib led to rapid reductions in SRT; however, in those receiving pegaptanib, these improvements were not maintained (at week 54, -0.22 mm³ vs. +0.18 mm³). Acute increases in SRF were seen 1 week after PDT (+0.36 mm³) and, across all treatment groups, PED volume tended to remain unchanged or to regress only slowly. CONCLUSIONS: In clinical trials, quantitative OCT subanalysis increases the amount of clinically useful information that can be obtained from OCT images. In the emerging era of neovascular AMD therapeutics, the capacity of OCT to provide such detailed pharmacodynamic information in a noninvasive manner is likely to attain increased importance. In future comparative studies, evaluation of SRT may highlight differential effects on vascular proliferation, whereas measurement of PED volume may be useful for the estimation of retinal and subretinal pigment epithelium (RPE) therapeutic penetration. (ClinicalTrials.gov number, ISRCTN83325075.).

Clinical significance of B-scan averaging with SD-OCT.

Averaging multiple scans is a potential advantage of optical coherence tomography. The authors evaluate the qualitative benefits of B-scan averaging on the visualization of outer retinal structures. A retrospective analysis was performed on Cirrus OCT (Carl Zeiss Meditec, Dublin, CA) B-scans from 1 eye of 35 patients referred to the imaging unit who underwent three types of scan acquisitions: no averaging, 4× averaging, and 20× averaging. Masked assessment of quality was made using a qualitative scale of 0 (worst) to 3 according to the ability to identify structure, brightness, and continuity. Quality scores consistently improved with 4× averaging, but improved only slightly further with 20×. Averaging appeared to have a statistically significant beneficial effect for the assessment of the external limiting membrane and outer nuclear layer (P < .05), with no significant benefit for visualization of the retinal pigment epithelium and inner segment/outer segment junction. The benefits of oversampling or averaging B-scans for visualizing outer retinal substructures are apparent even when averaging relatively few frames. These findings may be helpful when designing acquisition protocols in clinical trials and clinical practice.

Comparison of manually corrected retinal thickness measurements from multiple spectral-domain optical coherence tomography instruments.

BACKGROUND/AIMS: To compare retinal thickness measurements from three different spectral domain optical coherence instruments when manual segmentation is employed to standardise retinal boundary locations. METHODS: 40 eyes of 21 healthy subjects were scanned on the Cirrus HD-OCT, Topcon 3D-OCT-2000 and Heidelberg Spectralis-OCT. Raw data were imported into custom grading software (3D-OCTOR). Manual segmentation was performed on every data set, and retinal thickness values in the foveal central subfield were computed. RESULTS: 37 eyes of 20 subjects were gradable on every machine. The average retinal thicknesses for these eyes were 236.7 µm (SD 20.1), 235.7 µm (SD 20.4) and 236.5 µm (SD 18.0) for the Cirrus, 3D-OCT-2000 and Spectralis, respectively. Comparing manual retinal thickness measurements between any two machines, the maximum difference was 18.2 µm. The mean absolute differences per eye between two machines were: 4.9 µm for Cirrus versus 3D-OCT-2000, 3.7 µm for Cirrus versus Spectralis and 4.4 µm for 3D-OCT-2000 versus Spectralis. CONCLUSIONS: When a uniform position is used to locate the outer retinal boundary, the retinal thickness measurements derived from three different spectral domain optical coherence instruments devices are virtually identical. Manual correction may allow OCT-derived thickness measurements to be compared between devices in clinical trials and clinical research.

Bevacizumab and ranibizumab tachyphylaxis in the treatment of choroidal neovascularisation.

AIMS: To evaluate the effect of switching to bevacizumab or ranibizumab after developing tachyphylaxis during anti-vascular endothelial growth factor (VEGF) therapy for choroidal neovascularisation (CNV). METHODS: The authors reviewed the records of all patients who received both ranibizumab and bevacizumab for treatment of CNV to identify those who developed tachyphylaxis, defined as optical coherence tomography evidence of initial decreased exudation followed by lack of further reduction or an increase in exudation. Signs of exudation included subretinal fluid (SRF), pigment epithelial detachment (PED) and/or cystoid macular oedema (CMO). RESULTS: 26 eyes were included. 10 were initially treated with bevacizumab and then changed to ranibizumab for persistent SRF, PED and/or CMO. Of these, seven had occult CNV and three had predominantly classic CNV. One eye in the occult CNV group did not respond after being switched to ranibizumab. Six eyes had a positive therapeutic response, after one injection in four eyes, and after two or three injections in one eye each. In the classic group, two responded to ranibizumab and one did not. Sixteen eyes were initially treated with ranibizumab before changing to bevacizumab. Of these, 15 had occult CNV and 1 was predominantly classic. Three of the 16 eyes failed to respond to bevacizumab; 6 improved after one injection and 5 after two injections. CONCLUSIONS: Patients with CNV who develop tachyphylaxis to ranibizumab or bevacizumab may respond to another anti-VEGF drug. The majority of cases (81%) in this series demonstrated at least some response after switching therapies.

Spatial distribution of posterior pole choroidal thickness by spectral domain optical coherence tomography.

PURPOSE: To study the spatial distribution of posterior pole choroidal thickness (CT) in healthy eyes using spectral domain optical coherence tomography (SD-OCT). METHODS: Fifty-nine eyes from 30 subjects with no retinal or choroidal disease were examined with high-definition (HD) OCT using macular volume cube scanning protocols. A randomly chosen subset also had multifield analysis performed (volume scans centered on and surrounding the optic nerve head [ONH]). CT was manually quantified using a validated reading center tool. For macular scans, mean CT was calculated for each Early Treatment Diabetic Retinopathy Study subfield. Compound posterior pole CT maps were also created through the alignment of OCT projection images. Regression analyses were used to evaluate the correlation between CT and axial length (AL), refractive error, age, sex, and ethnicity. RESULTS: Subfoveal CT was 297.8 ± 82.2 µm, which did not differ significantly from that of the inner macular subfields. CT was greatest in the superior outer subfield and thinnest in the nasal outer subfield. The most predictive models for macular CT included AL and/or age. Outside the macula, CT was thinnest inferonasal to the ONH. CONCLUSIONS: CT demonstrates large variations between individuals, but also at different locations within the posterior pole; substantial choroidal thinning inferonasal to the ONH was demonstrated. CT appears to correlate more with distance from the optic nerve than from the fovea and, thus, in future studies, the ONH may serve as a better reference point than the foveal center for expressing or depicting regional CT variations.

Simple estimation of clinically relevant lesion volumes using spectral domain-optical coherence tomography in neovascular age-related macular degeneration.

PURPOSE: To evaluate simple methods of estimating the volume of clinically relevant features in neovascular age-related macular degeneration (NVAMD) using spectral domain-optical coherence tomography (SD-OCT). METHODS: Using a database of NVAMD cases imaged with macular cube (512 A-scans × 128 B-scans) SD-OCT scans, the authors retrospectively selected visits where cystoid macular edema (CME), subretinal fluid (SRF), or pigment epithelial detachments (PEDs) were evident. Patients with single visits were analyzed in the cross-sectional analysis (CSA) and those with a baseline visit and three or more follow-up visits in the longitudinal analysis (LA). The volume of each feature was measured by manual grading using validated grading software. Simplified measurements for each feature included: number of B-scans or A-scans involved and maximum height. Automated measurements of total macular volume and foveal central subfield were also collected from each machine. Correlations were performed between the volumes measured with 3D-OCTOR, automated measurements, and the simplified measures. RESULTS: Forty-five visits for 25 patients were included in this study: 26 cube scans from 26 eyes of 25 patients in the CSA and 24 scans from 5 eyes of 5 patients in the LA. The simplified measures that correlated best with manual grading in the CSA group were maximum lesion height for CME (r² value = 0.96) and B-scan count for SRF and PED volume (r² values of 0.88 and 0.70). In the LA group, intervisit differences were correlated. Change in B-scan count correlated well with change in SRF volume (r² = 0.97), whereas change in maximum height correlated with change in CME and PED volume (r² = 0.98 and 0.43, respectively). CONCLUSIONS: These data suggest that simplified estimators of some NVAMD lesion volumes exist and are accessible by clinicians without the need for specialized software or time-consuming manual segmentation. These simple approaches could enhance quantitative disease monitoring strategies in clinical trials and clinical practice.

Binocular optical coherence tomography.

The use of optical coherence tomography (OCT) in the field of ophthalmology has increased rapidly in recent years and may continue on this trajectory as more indications for OCT imaging are described. Recent pressures on the healthcare system, such as rising costs, increasing demand, and decreasing reimbursements, suggest that continued growth in OCT use may be unsustainable unless cheaper and more efficient methods are developed. Binocular OCT has the potential to decrease the cost, increase the quality, and improve the efficiency not just of OCT imaging, but of eye care as a whole. Binocular OCT devices should be cheaper to build and operate than conventional OCT instruments. They may be able to replace labor-intensive, qualitative tests with patient-operated, quantitative examinations. They could also usher in a new era of comprehensive, remote eye care and eye disease screening that has the potential to reengineer the practice of ophthalmology.

Relationship between outer retinal thickness substructures and visual acuity in eyes with dry age-related macular degeneration.

PURPOSE: To explore the correlation between outer retinal substructures and visual acuity in dry age-related macular degeneration (AMD). METHODS: Analysis of spectral domain optical coherence tomography datasets from 100 eyes of 100 consecutive patients with dry AMD was performed. The internal limiting membrane, outer nuclear layer (ONL), external limiting membrane (ELM), inner segment-outer segment (IS-OS) junction, outer photoreceptor border, inner and outer retinal pigment epithelium (RPE) borders, and Bruch's membrane, were manually segmented by Doheny Image Reading Center (DIRC) graders. Areas, thicknesses, and volumes of RPE, IS, OS, ONL, and the total retina in the foveal central subfield were correlated with the logarithm of minimal angle of resolution (logMAR) visual acuity using univariable and multivariable regression analysis. RESULTS: The visual acuity in this group ranged from logMAR 0 to 1.3 with a mean of 0.23. Areas, thicknesses, and volumes of ONL, IS and OS, thicknesses of total retinal and RPE, and intensities of IS, OS, and RPE, showed statistically significant association (P < 0.05) with logMAR best corrected visual acuity. The highest correlations were observed for the ONL (thickness: r = -0.49, volume: -0.47, area: -0.50) and photoreceptor IS (thickness: -0.59, area: -0.63, volume: -0.53). The model with the highest correlation in this study included thicknesses of ONL, IS, OS and RPE, as well as area of ONL, IS, OS, RPE, and intensity of RPE. CONCLUSIONS. Although integrity of outer retinal substructures in the foveal central subfield correlates with visual acuity in the eyes of patients with dry AMD, the correlation is only moderate and does not fully explain the variability in acuity in these cases.

Ultra-wide-field green-light (532-nm) autofluorescence imaging in chronic Vogt-Koyanagi-Harada disease.

BACKGROUND AND OBJECTIVE: To assess the prevalence of peripheral fundus autofluorescence (FAF) abnormalities in chronic Vogt-Koyanagi-Harada disease (VKH). PATIENTS AND METHODS: A retrospective review of cases at the Doheny Eye Institute between December 2009 and April 2010. Patients with chronic VKH who had ultra-wide-field FAF and pseudo-color imaging performed were included. All images were reviewed independently by two reading center certified retina specialists. RESULTS: Twenty eyes of 10 patients were included in this analysis. Fourteen eyes of 7 patients (70%) showed peripheral changes on FAF images outside the posterior pole. Three different patterns were observed: multifocal hypofluorescent spots (n = 11 eyes), hyperfluorescent spots (n = 8 eyes), and a unique lattice-like pattern in both eyes of one patient. There were noticeable disparities between FAF and color images. CONCLUSION: Peripheral FAF abnormalities are frequent in chronic VKH and are readily revealed by wide-field FAF imaging and manifesting with distinct patterns. Further investigation in prospective studies is warranted.

Relationship between optical coherence tomography retinal parameters and visual acuity in diabetic macular edema.

PURPOSE: To investigate the relationship between optical coherence tomography (OCT)-derived measurements of retinal morphology and visual acuity in patients with diabetic macular edema. DESIGN: Retrospective cross-sectional study. PARTICIPANTS: A total of 67 consecutive patients (67 eyes) with diabetic macular edema (DME) who underwent Stratus OCT imaging (Carl Zeiss Meditec, Inc., Dublin, CA). METHODS: Best-corrected Snellen visual acuity was recorded for each patient. Raw exported Stratus OCT images for each patient were analyzed using custom software entitled "OCTOR," which allows the precise positioning of prespecified boundaries on individual B-scans. Thickness, volume, and intensity were calculated for neurosensory retina and subretinal fluid. In addition, photoreceptor outer segment (POS) thickness was quantified. MAIN OUTCOME MEASURES: Optical coherence tomography-derived measurements of retinal morphology and visual acuity. RESULTS: The Spearman coefficient values (r) of the correlation between OCTOR-derived measurements of central subfield thickness, intensity, subretinal fluid volume, and POS thickness and the logarithm of the minimum angle of resolution visual acuities were 0.3428 (P = 0.005), -0.2658 (P = 0.03), -0.2683 (P = 0.38), and -0.3703 (P = 0.002), respectively. Multivariate models with stepwise selection revealed a cumulative R(2) of 0.4305 in the total study population, with R(2) of 0.4999 and 0.7628 in the untreated and prior focal laser groups, respectively. CONCLUSIONS: Subanalysis and quantification of OCT features in eyes with DME seem to be of value. In particular, POS thickness seems to be an important predictor of function and visual acuity in patients with DME.

Effects of retinal morphology on contrast sensitivity and reading ability in neovascular age-related macular degeneration.

PURPOSE: To investigate the effect of changes in retinal morphology on contrast sensitivity and reading ability in patients with neovascular age-related macular degeneration (AMD) in the Avastin (bevacizumab; Genentech, South San Francisco, CA) for choroidal neovascularization (ABC) Trial. METHODS: Contrast sensitivity obtained with Pelli-Robson charts, reading ability assessed with Minnesota Reading charts, and Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity (VA) obtained by protocol refraction, were recorded. Raw Stratus optical coherence tomography (OCT; Carl Zeiss Meditec, Inc., Dublin, CA) images were analyzed with the publicly available software OCTOR, which allows precise delineation of any retinal compartment of interest. Thickness and volume were calculated for neurosensory retina, subretinal fluid (SRF), subretinal tissue, and pigment epithelium detachment, and the resulting measurements were correlated with each visual function parameter. RESULTS: One hundred twenty-two patients with newly diagnosed neovascular AMD and enrolled in the ABC Trial, were evaluated. Increased subretinal tissue volume correlated with decreased contrast sensitivity (Pearson's correlation coefficient, r = -0.4944, P = 0.001). A modest correlation was detected between SRF volume and contrast sensitivity (r = -0.2562, P = 0.004). Increased retinal thickness at the foveal center also correlated with decreased visual function (ETDRS VA: r = -0.4530, P < 0.001). CONCLUSIONS: The strongest correlation detected between the functional parameters assessed and any of the OCT-derived morphologic parameters was that between decreased contrast sensitivity and increased subretinal tissue. In the future, assessment of contrast sensitivity and reading ability, in combination with quantitative subanalysis of retinal compartments, may lead to the identification of parameters relevant to functional improvement and ultimate prognosis in patients with newly diagnosed neovascular AMD (www.controlled-trials.com number, ISRCTN83325075).