DEVELOPMENT AND VALIDATION OF AN EXPLAINABLE ARTIFICIAL INTELLIGENCE FRAMEWORK FOR MACULAR DISEASE DIAGNOSIS BASED ON OPTICAL COHERENCE TOMOGRAPHY IMAGES.

PURPOSE: To develop and validate an artificial intelligence framework for identifying multiple retinal lesions at image level and performing an explainable macular disease diagnosis at eye level in optical coherence tomography images. METHODS: A total of 26,815 optical coherence tomography images were collected from 865 eyes, and 9 retinal lesions and 3 macular diseases were labeled by ophthalmologists, including diabetic macular edema and dry/wet age-related macular degeneration. We applied deep learning to classify retinal lesions at image level and random forests to achieve an explainable disease diagnosis at eye level. The performance of the integrated two-stage framework was evaluated and compared with human experts. RESULTS: On testing data set of 2,480 optical coherence tomography images from 80 eyes, the deep learning model achieved an average area under curve of 0.978 (95% confidence interval, 0.971-0.983) for lesion classification. In addition, random forests performed accurate disease diagnosis with a 0% error rate, which achieved the same accuracy as one of the human experts and was better than the other three experts. It also revealed that the detection of specific lesions in the center of macular region had more contribution to macular disease diagnosis. CONCLUSION: The integrated method achieved high accuracy and interpretability in retinal lesion classification and macular disease diagnosis in optical coherence tomography images and could have the potential to facilitate the clinical diagnosis.

Consensus Nomenclature for Reporting Neovascular Age-Related Macular Degeneration Data: Consensus on Neovascular Age-Related Macular Degeneration Nomenclature Study Group.

PURPOSE: To establish a process to evaluate and standardize a state-of-the-art nomenclature for reporting neovascular age-related macular degeneration (AMD) data. DESIGN: Consensus meeting. PARTICIPANTS: An international panel of retina specialists, imaging and image reading center experts, and ocular pathologists. METHODS: During several meetings organized under the auspices of the Macula Society, an international study group discussed and codified a set nomenclature framework for classifying the subtypes of neovascular AMD and associated lesion components. MAIN OUTCOME MEASURES: A consensus classification of neovascular AMD. RESULTS: The study group created a standardized working definition of AMD. The components of neovascular AMD were defined and subclassified. Disease consequences of macular neovascularization were delineated. CONCLUSIONS: The framework of a consensus nomenclature system, a definition of AMD, and a delineation of the subtypes of neovascular AMD were developed. Establishing a uniform set of definitions will facilitate comparison of diverse patient groups and different studies. The framework presented is modified and updated readily, processes that are anticipated to occur on a periodic basis. The study group suggests that the consensus standards outlined in this article be used in future reported studies of neovascular AMD and clinical practice.

VISUAL PROGNOSIS AFTER PNEUMATIC DISPLACEMENT OF SUBMACULAR HEMORRHAGE ACCORDING TO AGE-RELATED MACULAR DEGENERATION SUBTYPES.

PURPOSE: This study compared the visual outcome after pneumatic displacement of submacular hemorrhage among patients with different subtypes of age-related macular degeneration (AMD). METHODS: We retrospectively reviewed the medical records of 67 patients (67 eyes) who underwent treatment for submacular hemorrhage associated with AMD. All the patients underwent pneumatic displacement. Demographic parameters, visual acuity, and anatomical features were analyzed among AMD subtypes: typical AMD, polypoidal choroidal vasculopathy (PCV), and retinal angiomatous proliferation (RAP). RESULTS: Among the eyes with submacular hemorrhage, 24, 30, and 13 eyes had typical AMD, PCV, and RAP, respectively. Post-treatment best-corrected visual acuity was best in the PCV group and worst in the RAP group (P < 0.001). The proportion of eyes with improved visual acuity was highest in the PCV subtype and lowest in the RAP subtype (P = 0.044). Logistic regression analysis showed that AMD subtype (P = 0.016) and time to treatment (<7 days) (P = 0.037) are associated with the final visual outcome. CONCLUSION: The final post-treatment visual outcome after the incidence of submacular hemorrhage was best in the PCV group and worst in the RAP group. Age-related macular degeneration subtype is a significant factor associated with the visual prognosis of submacular hemorrhage.

COLORADO AGE-RELATED MACULAR DEGENERATION REGISTRY: Design and Clinical Risk Factors of the Cohort.

PURPOSE: To study new and existing risk factors related to age-related macular degeneration (AMD) phenotypes in a Colorado cohort. METHODS: Age-related macular degeneration was categorized into early, intermediate, or advanced forms. Controls (n = 180) were patients with cataract and no AMD. Demographic and clinical data were gathered by patient interview and verified by chart review. Image data were reviewed by vitreoretinal specialists. Statistical analysis included univariable and multivariate logistic regression analysis (P < 0.05). RESULTS: Among the 456 patients with AMD, 157 (34.4%), 80 (17.6%), and 219 (48.0%) had the early/intermediate, geographic atrophy, and neovascular forms of the disease, respectively. Adjusted for age, African-American race was associated with a reduced risk of early/intermediate (adjusted odds ratio [AOR] = 0.08, confidence interval [CI] = 0.01-0.67) and neovascular AMD (AOR = 0.15, CI = 0.03-0.72). A family history of AMD was a risk factor for early/intermediate (AOR = 4.08, CI = 2.30-7.25), geographic atrophy (AOR = 8.62, CI = 3.77-19.7), and neovascular AMD (AOR = 3.76, CI = 2.16-6.56). A history of asthma was related to the early/intermediate form of AMD (AOR = 2.34, CI = 1.22-4.46). CONCLUSION: Studying AMD in specific populations may reveal novel risk factors such as our finding of a relationship between asthma history and AMD.

Variable response of subretinal hyperreflective material to anti-vascular endothelial growth factor classified with optical coherence tomography angiography.

PURPOSE: To evaluate the prognosis and response of neovascular age-related macular degeneration (AMD) to anti-vascular endothelial growth factor (VEGF), according to the components of subretinal hyperreflective material (SHRM) classified using optical coherence tomography angiography (OCTA), is the aim of this study. METHODS: We retrospectively studied 39 eyes of 39 consecutive patients with SHRM associated with exudative AMD, who underwent standard examination and multimodal imaging, including fundus photography, optical coherence tomography (OCT), and OCTA. We classified SHRM into type 2 neovascularization (NV), fibrosis, subretinal hyperreflective exudation (SHE), and hemorrhage using OCTA. If compound SHRM was found, components in the foveal center were considered. All patients except one with fibrosis received anti-VEGF treatment for more than 12 months. The best-corrected visual acuity (BCVA) values measured before treatment and at 3, 6, and 12 months after the first injection were compared according to the components of SHRM. RESULTS: Using OCTA, 11 eyes with type 2 NV showed abnormal blood flow and 1 eye with fibrosis showed strong surface projection. Both SHE and hemorrhage components showed projection artifact with no intrinsic flow. However, OCTA enabled eyes with SHE (17 eyes) to be distinguished from those with hemorrhage (10 eyes) because hemorrhage showed masking of choriocapillaris flow. Eyes with SHE showed a significant improvement in the mean logMAR BCVA as compared with the value at the baseline, which was sustained throughout the 12-month follow-up period (p < 0.05). In eyes with type 2 NV and hemorrhage, no significant difference in the mean BCVA values was observed at any follow-up time-point (all, p > 0.05). CONCLUSION: OCTA was useful to noninvasively distinguish SHRM components. It may be important to consider the components of SHRM to predict the visual acuity in patients with AMD.

Imaging Protocols in Clinical Studies in Advanced Age-Related Macular Degeneration: Recommendations from Classification of Atrophy Consensus Meetings.

PURPOSE: To summarize the results of 2 consensus meetings (Classification of Atrophy Meeting [CAM]) on conventional and advanced imaging modalities used to detect and quantify atrophy due to late-stage non-neovascular and neovascular age-related macular degeneration (AMD) and to provide recommendations on the use of these modalities in natural history studies and interventional clinical trials. DESIGN: Systematic debate on the relevance of distinct imaging modalities held in 2 consensus meetings. PARTICIPANTS: A panel of retina specialists. METHODS: During the CAM, a consortium of international experts evaluated the advantages and disadvantages of various imaging modalities on the basis of the collective analysis of a large series of clinical cases. A systematic discussion on the role of each modality in future studies in non-neovascular and neovascular AMD was held. MAIN OUTCOME MEASURES: Advantages and disadvantages of current retinal imaging technologies and recommendations for their use in advanced AMD trials. RESULTS: Imaging protocols to detect, quantify, and monitor progression of atrophy should include color fundus photography (CFP), confocal fundus autofluorescence (FAF), confocal near-infrared reflectance (NIR), and high-resolution optical coherence tomography volume scans. These images should be acquired at regular intervals throughout the study. In studies of non-neovascular AMD (without evident signs of active or regressed neovascularization [NV] at baseline), CFP may be sufficient at baseline and end-of-study visit. Fluorescein angiography (FA) may become necessary to evaluate for NV at any visit during the study. Indocyanine-green angiography (ICG-A) may be considered at baseline under certain conditions. For studies in patients with neovascular AMD, increased need for visualization of the vasculature must be taken into account. Accordingly, these studies should include FA (recommended at baseline and selected follow-up visits) and ICG-A under certain conditions. CONCLUSIONS: A multimodal imaging approach is recommended in clinical studies for the optimal detection and measurement of atrophy and its associated features. Specific validation studies will be necessary to determine the best combination of imaging modalities, and these recommendations will need to be updated as new imaging technologies become available in the future.

Photoreceptor dysfunction in early and intermediate age-related macular degeneration assessed with mfERG and spectral domain OCT.

PURPOSE: To evaluate the changes of the photoreceptor layer (PRL) thickness with spectral domain optical coherence tomography (SD-OCT) and the retinal function by mfERG, as well as the correlation of morphology and function parameters in subjects with early and intermediate age-related macular degeneration (AMD). METHODS: Subjects with clinical diagnosis of early or intermediate AMD and age-matched healthy subjects were recruited prospectively in this study. Color fundus photography, SD-OCT, and mfERG were conducted. Retinal photoreceptor thickness was measured, and first-order kernel responses were recorded. The differences between AMD group and control group were compared, and the correlations between macular photoreceptor thickness and the mfERG were analyzed. RESULTS: PRL thickness (µm) in four areas including foveola and 0.5, 1.5, and 3 mm away from foveola was 192.48 ± 17.37, 163.73 ± 12.95, 130.93 ± 9.20, and 108.78 ± 7.81, respectively, in normal eyes, whereas in AMD group, they were 158.61 ± 45.25, 138.91 ± 20.92, 118.91 ± 12.85, and 95.00 ± 9.64, respectively (P < 0.001). The mean amplitude response densities of AMD patients decreased significantly compared to the control group in ring 1-6 (P < 0.001). The mean mfERG N1 and P1 latency of AMD patients prolonged compared to the control group, except the ring 1 (P = 0.588 and P = 0.084). The macular PRL thickness was significantly associated with the mfERGN1 and P1 amplitude density in ring 1-4 (r = 0.338-0.533, P < 0.01). CONCLUSIONS: PRL thickness decreases are in accordance with the deterioration of retinal electrophysiological activity. The retinal PRL thickness is important parameter to assess of early and intermediate AMD severity.

PATTERNS OF FUNDUS AUTOFLUORESCENCE DEFECTS IN NEOVASCULAR AGE-RELATED MACULAR DEGENERATION SUBTYPES.

PURPOSE: To test define characteristic fundus autofluorescence patterns of different exudative age-related macular degeneration subtypes. METHODS: Cross-sectional study. Fifty-two patients with choroidal neovascularization because of three different neovascular age-related macular degeneration subtypes were included in the study. Macular and peripheral fundus autofluorescence patterns of study subjects were compared in a masked fashion. RESULTS: Fundus autofluorescence patterns of all three neovascular age-related macular degeneration subtypes revealed similar patterns. However, peripapillary hypo-autofluorescence was more common among patients with polypoidal choroidal vasculopathy (88.2%) compared with patients with retinal angiomatous proliferation (12.5%) and patients without retinal angiomatous proliferation and polypoidal choroidal vasculopathy (21.1%) (P < 0.0001). CONCLUSION: Presence of peripapillary fundus autofluorescence defects in neovascular age-related macular degeneration maybe suggestive of polypoidal choroidal vasculopathy as a variant of neovascular age-related macular degeneration.

Geographic atrophy in patients receiving anti-vascular endothelial growth factor for neovascular age-related macular degeneration.

PURPOSE: To examine factors associated with the apparent growth of geographic atrophy (GA) in a consecutive series of eyes with treatment-naive neovascular age-related macular degeneration receiving intravitreal anti-vascular endothelial growth factor therapy on a treat-and-extend regimen. METHODS: This was a retrospective cohort study. Two independent graders identified areas of GA using near-infrared reflectance imaging and spectral domain optical coherence tomography (SD-OCT). Neovascular lesion subtypes were classified based on fluorescein angiography (FA) as occult choroidal neovascularization, classic choroidal neovascularization, retinal angiomatous proliferation, or mixed choroidal neovascularization, and by the anatomical classification system which utilizes FA and SD-OCT as Types 1 (sub-retinal pigment epithelium), 2 (subretinal), 3 (intraretinal), or mixed neovascularization. RESULTS: Ninety-one patients (94 eyes) fit the inclusion criteria, of which 52 eyes (55.3%) experienced apparent GA growth. The odds of developing apparent GA were significantly lower in Type 1 neovascularization compared to the other lesion types (P < 0.001). Using both FA and SD-OCT to classify neovascular age-related macular degeneration significantly improves the goodness of fit in the correlation between apparent GA growth and baseline neovascular lesion type (P < 0.001). CONCLUSION: Treatment-naive neovascular age-related macular degeneration eyes with Type 1 neovascularization at baseline were less likely to develop GA than eyes with other types. The correlation between apparent GA growth and subtype of neovascularization is stronger when lesions are classified with an anatomic grading that utilizes both FA and SD-OCT.

Correlation between neovascular lesion type and clinical characteristics of nonneovascular fellow eyes in patients with unilateral, neovascular age-related macular degeneration.

PURPOSE: To investigate the association between the type of neovascularization (NV) and the clinical characteristics of nonneovascular fellow eyes in patients with unilateral, neovascular age-related macular degeneration. METHODS: Eighty-three patients with treatment-naive, unilateral, neovascular age-related macular degeneration were retrospectively analyzed. Neovascular lesions were classified using both fluorescein angiography and optical coherence tomography as Type 1 (subretinal pigment epithelium), 2 (subretinal), 3 (intraretinal), or mixed NV. The associations between NV lesion type and baseline clinical and imaging characteristics of the fellow eye, including central geographic atrophy, noncentral geographic atrophy, pigmentary changes, soft drusen, cuticular drusen, reticular pseudodrusen, and subfoveal choroidal thickness, were examined. Subfoveal choroidal thickness was defined as thin if thickness was <120 µm. RESULTS: In the fellow eyes of patients with treatment-naive, unilateral, neovascular age-related macular degeneration, Type 3 NV had an increased adjusted odds ratio of reticular pseudodrusen (15.361, P < 0.001) and thin subfoveal choroidal thickness (21.537, P < 0.001) as well as a tendency toward an increased adjusted odds ratio of central geographic atrophy (4.775, P = 0.028). Fellow eyes of patients with Type 1 NV showed a decreased adjusted odds ratio of reticular pseudodrusen (0.233, P = 0.007) and thin subfoveal choroidal thickness (0.080, P = 0.005). CONCLUSION: In patients with unilateral, neovascular age-related macular degeneration, certain nonneovascular features of the fellow eye correlate with the NV lesion composition based on type, as anatomically classified utilizing both fluorescein angiography and optical coherence tomography. Patients with Type 3 NV were more likely to have reticular pseudodrusen and/or thin subfoveal choroidal thickness in the fellow eye compared with those with Type 1 NV. Patients with Type 3 NV also showed a trend toward increased central geographic atrophy in the fellow eye.

Prevalence of Age-Related Macular Degeneration in Portugal: The Coimbra Eye Study - Report 1.

PURPOSE: To evaluate the age- and gender-specific prevalence of early and late age-related macular degeneration (AMD) in a Portuguese population-based sample. METHODS: All patients aged ≥55 years of a Portuguese primary health-care unit were recruited for a cross-sectional population-based study. Responders underwent complete ophthalmological examination and digital fundus imaging. Early and late AMD was defined according to the International Age-Related Macular Epidemiological Study Group Classification, and the adopted staging for AMD was the same as that used in the Rotterdam study. The age- and gender-adjusted prevalence of early and late forms of AMD was calculated. RESULTS: Of the 4,370 eligible subjects, 3,000 underwent study procedures (68.6% response rate) and 2,975 were included in the analysis; they had a mean age of 68.9 ± 8.6 years. The overall prevalence of early and late AMD was 15.53% (95% CI 14.25-16.88) and 0.67% (95% CI 0.41-1.04), respectively. Neovascular AMD (NV-AMD) and geographic atrophy (GA) accounted for 0.44% (95% CI 0.23-0.75) and 0.27% (95% CI 0.12-0.53) of individuals, respectively. The highest prevalence of advanced AMD was among those aged ≥75 years (1.13% for NV-AMD; 0.63% for GA). CONCLUSIONS: To our knowledge, this is the first AMD epidemiological study in a Portuguese population. The early forms of the disease had a similar prevalence to that of other large-scale population-based cohorts, but late AMD was less frequent than previously reported.

Prevalence of anti-retinal autoantibodies in different stages of Age-related macular degeneration.

BACKGROUND: Age-related macular degeneration (AMD) is the leading cause of central vision loss in older adults. Anti-retinal autoantibodies (AAbs) have been found in individuals with AMD. The goal of the study was to determine the AAb specificity in different stages of AMD, and determine whether there is a prevalent AAb signature. METHODS: Sera of 134 participants in the Age-related Eye Disease Study were analyzed for anti-retinal AAbs by western blotting. The subjects were classified by diagnostic subgroups based upon their clinical classification: No AMD, Intermediate AMD, and Late AMD - geographic atrophy (GA) and Late AMD - neovascular (NV). RESULTS: The presence of anti-retinal AAb was detected in 58% patients with Intermediate and Late AMD, and 54% of those with no AMD. AAbs bound to fifteen different retinal antigens. Most individuals had 1 specific AAbs (67%), with the remainder having 2 to 4 different AAbs. Over 40% of patients with Intermediate AMD, and 46% of those with GA had anti-enolase AAbs, compared with 29% of individuals with NV and 29% with no AMD. Different AAbs signatures related to NV as compared to GA and/or Intermediate AMD were distinguished. Anti-40-kDa (10%) and 42-kDa (16%) autoantibodies were associated with Intermediate AMD, while anti-30-kDa AAbs (23%) were primarily present in GA. Anti-32-kDa (12%), 35-kDa (21%), and 60-kDa (8%) AAbs were more frequent in NV AMD. CONCLUSIONS: A unique AAb pattern for each of the disease subgroups was present when AMD progressed from the intermediate to the late forms of severity. Differences in the frequency of specific AAbs between AMD subgroups suggested that they may participate in pathogenicity of AMD. Further studies are necessary to confirm these observations in the larger cohort and individual AMD patients over time.

Age-related macular degeneration: linking clinical presentation to pathology.

Age-related macular degeneration (AMD) is one of the leading causes of blindness worldwide in the elderly population. Optometrists, as primary eye health care providers, require the skills and knowledge to accurately diagnose and manage AMD patients. There is an overwhelming body of research related to the clinical presentation, etiology, epidemiology, and pathology of this disease. Additionally, the evolution of new imaging modalities creates new opportunities to clinically detect and analyze previously uncharacterized and earlier changes in the retina. The challenge for optometrists is to combine all this information into an applicable knowledge base for use in everyday clinical assessment of AMD so that timely and accurate referrals can be made to retinal specialists. This review attempts to address this issue by linking the clinical presentation of AMD with the underlying disease biology. We emphasize the contribution of recent noninvasive imaging technologies to the clinical assessment of early and more advanced AMD including optical coherence tomography, fundus autofluorescence, and infrared reflectance.

Intraocular growth factors and cytokines in patients with dry and neovascular age-related macular degeneration.

PURPOSE: To analyze intraocular growth factor and cytokine concentrations in eyes with different stages of age-related macular degeneration (AMD) compared with controls. METHODS: The Clinical Age-Related Maculopathy Staging (CARMS) system was used for assignment of patients into the respective categories. Aqueous humor specimens were taken before cataract surgery in 21 controls (CARMS 1) and in 17 early (CARMS 2) and 16 intermediate (CARMS 3) AMD patients. In 18 neovascular (CARMS 5) AMD patients, specimens were taken immediately before anti-vascular endothelial growth factor intravitreal therapy. Luminex multiplex bead assays were conducted for endostatin, angiogenin, vascular endothelial growth factor, platelet-derived growth factor AA, placental growth factor, thrombospondin 2, and fibroblast growth factor a. RESULTS: Vascular endothelial growth factor concentrations were elevated in CARMS 3 (P = 0.037) and tended to be elevated in CARMS 5 (P = 0.093), whereas levels in CARMS 2 (P = 0.425) were similar to CARMS 1. Platelet-derived growth factor levels were diminished in CARMS 2 (P = 0.020), with a trend to lower levels for CARMS 3 (P = 0.099) and CARMS 5 (P = 0.082) compared with CARMS 1. For CARMS 5, antiangiogenic endostatin was elevated (P < 0.002), while antiangiogenic thrombospondin 2 was reduced (P = 0.029). CONCLUSION: Clinical Age-Related Maculopathy Staging 3 dry AMD was associated with higher vascular endothelial growth factor levels than CARMS 5 neovascular AMD. Therefore, intraocular vascular endothelial growth factor concentrations do not seem to reflect choroidal neovascularization activity in neovascular AMD directly. Platelet-derived growth factor was decreased in most forms of AMD. The antiangiogenic endostatin was exclusively elevated in neovascular AMD, while thrombospondin 2 was reduced. Age-related macular degeneration disease seems to be associated with a generally altered cytokine system.

OCT-A characterisation of recurrent type 3 macular neovascularisation.

PURPOSE: To investigate optical coherence tomography angiography (OCT-A) findings in recurrent type 3 macular neovascularisation (MNV). METHODS: In this retrospective cohort study, consecutive patients with type 3 MNV secondary to age-related macular degeneration underwent OCT-A at three different time points: baseline, after anti-vascular endothelial growth factor treatment with complete resolution of the exudative signs (ie, non-exudative stage) and at the recurrence of exudation (ie, recurrence stage). Demographics and clinical findings were analysed, including OCT-A features of type 3 MNV recurrence. RESULTS: Twelve eyes (12 patients, mean age 78±7 years) were included. Using OCT-A, at baseline all type 3 MNVs showed the presence of detectable flow downgrowing from the deep vascular complex (DVC) to the retinal pigment epithelium (RPE)/sub-RPE space. 6/12 eyes (50%) showed anomalous flow under the RPE, while the other 6 eyes showed flow reaching the RPE without anomalous flow in the sub-RPE space. At the non-exudative stage (after treatment), BCVA and CMT significantly improved (p=0.004 and p=0.036), and flow inside the retinal lesions reduced; interestingly the connection to the RPE/sub-RPE space regressed. At the time of recurrence, all type 3 MNVs showed the presence of intra/sub-retinal exudation with restoration of the flow deepening from the DVC to the RPE/sub-RPE space. CONCLUSIONS: Detectable flow deepening from the DVC to the RPE/sub-RPE space using OCT-A is mandatory to have a new exudation secondary to recurrent type 3 MNV. Early detection of type 3 MNV recurrence by OCT-A characterisation may prompt retreatment and potentially prevent progression to late stages of the disease.

Classification of Exudative Age-Related Macular Degeneration With Pachyvessels on En Face Swept-Source Optical Coherence Tomography.

Purpose: The purpose of this study was to classify exudative maculopathy by the presence of pachyvessels on en face swept-source optical coherence tomography (SSOCT). Methods: Consecutive patients with signs of exudative maculopathy underwent SSOCT, fluorescein and indocyanine green angiography (ICGA), ultra-widefield fundus color photography, and autofluorescence examinations. Images were analyzed in a masked fashion by two sets of four examiners in different sessions: (1) the presence of pachyvessels in en face OCT and (2) features of exudative maculopathy in conventional imaging modalities. Quantitative data obtained were subfoveal choroidal thickness (SFCT) and choroidal vascularity index (CVI), which was the ratio of choroidal vessels lumen area to a specified choroidal area from binarized cross-sectional OCT scans. Results: Pachyvessels was observed in 38 (52.1%) of 73 eyes. The pachyvessels group was associated with younger age (69.1 ± 9.4 years, odds ratio [OR] = 0.95, 95% confidence interval [95% CI] = 0.90-0.97, P = 0.04), presence of polypoidal lesions (OR = 3.27, 95% CI = 1.24-8.62, P = 0.01), increased SFCT (OR = 1.08, 95% CI = 1.02-1.14, P < 0.01), and increased CVI (65.4 ± 5.3, OR = 1.12, 95% CI = 1.02-1.23, P = 0.01). In multivariate regression, CVI significantly correlated with pachyvessels (OR = 1.24, 95% CI = 1.03-1.55, P = 0.04). Conclusions: Exudative maculopathy could be classified based on differences in choroidal vasculature morphology. Current results implied that choroidal hemodynamics may be relevant to variable natural history and treatment response in neovascular AMD and polypoidal choroidal vasculopathy.

Prevalence of Age-Related Macular Degeneration in Australia: The Australian National Eye Health Survey.

Importance: Age-related macular degeneration (AMD) is a leading cause of irreversible blindness among the elderly population globally. Currently, knowledge of the epidemiology of AMD in Australia remains scarce because of a paucity of recent population-based data. Objective: To examine the prevalence of AMD in Australia. Design, Setting, and Participants: In this population-based, cross-sectional survey performed from March 11, 2015, to April 18, 2016, a sample of 3098 nonindigenous Australians 50 years and older and 1738 indigenous Australians 40 years and older from 30 geographic areas across Australia were examined. Main Outcomes and Measures: Any AMD, early AMD, intermediate AMD, and late AMD graded according to the Beckman clinical classification system. Results: A total of 4836 individuals were examined, including 3098 nonindigenous Australian (64.1%; 58.9% female vs 41.1% male; age range, 40-92 years; mean [SD] age, 55.0 [10.0] years) and 1738 indigenous Australians (35.9%; 53.6% female vs 46.4% male; age range, 50-98 years; mean [SD] age, 66.6 [9.7] years). A total of 4589 (94.9%, 2946 nonindigenous and 1643 indigenous) participants had retinal photographs in at least 1 eye that were gradable for AMD. The weighted prevalence of early AMD was 14.8% (95% CI, 11.7%-18.6%) and of intermediate AMD was 10.5% (95% CI, 8.3%-13.1%) among nonindigenous Australians. In indigenous Australians, the weighted prevalence of early AMD was 13.8% (95% CI, 9.7%-19.3%) and of intermediate AMD was 5.7% (96% CI, 4.7%-7.0%). Late AMD was found in 0.96% (95% CI, 0.59%-1.55%) of nonindigenous participants (atrophic, 0.72%; neovascular, 0.24%). The prevalence of late AMD increased to 6.7% in participants 80 years or older and was higher in men (1.4% vs 0.61%, P = .02). Only 3 (0.17% [95% CI, 0.04%-0.63%]) indigenous participants had late (atrophic) AMD. Age-related macular degeneration was attributed as the main cause of vision loss (<6/12 in the better eye) in 23 of 208 nonindigenous Australians (11.1%) and 2 of 183 indigenous Australians (1.1%). Conclusions and Relevance: In line with data from other white populations, AMD is a prominent cause of vision loss in the nonindigenous Australian population. An increased provision of low vision rehabilitation services may be required to cope with the projected increase in AMD in Australia.

Postreceptor Neuronal Loss in Intermediate Age-related Macular Degeneration.

PURPOSE: To investigate the relationship between ganglion cell complex (GCC) thickness and photoreceptor alterations in eyes with intermediate age-related macular degeneration (AMD). DESIGN: Retrospective case-control study. METHODS: We collected data from 68 eyes with intermediate AMD from 68 patients with spectral-domain optical coherence tomography (SDOCT) imaging. A control group of 50 eyes from 50 healthy subjects was included for comparison. Our main outcome measures for comparison between groups were (1) the average and minimum GCC thickness and (2) the "normalized" reflectivity of the ellipsoid zone (EZ) en face image. RESULTS: The average and minimum GCC thicknesses were thinner in AMD patients (69.54 ± 9.30 µm and 63.22 ± 14.11 µm, respectively) than in healthy controls (78.57 ± 6.28 µm and 76.28 ± 6.85 µm, P < .0001 and P < .0001, respectively). Agreement was found to be excellent in the "normalized" EZ reflectivity assessment (intraclass correlation coefficient = 0.986, coefficient of variation = 1.11). The EZ "normalized" reflectivity was 0.67 ± 0.11 in controls and 0.61 ± 0.09 in the AMD group (P = .006). In univariate analysis, EZ "normalized" reflectivity was found to have a significant direct relationship with average (P < .0001) and minimum (P < .0001) GCC thickness in AMD patients, but not in controls (P = .852 and P = .892, respectively). CONCLUSIONS: Eyes with intermediate AMD exhibit GCC thinning, as well as a reduced EZ "normalized" reflectivity, and these parameters are correlated. This study supports the concept of postreceptor retinal neuronal loss as a contributor to retinal thinning in intermediate AMD.