Photobiomodulation efficacy in age-related macular degeneration: a systematic review and meta-analysis of randomized clinical trials.

BACKGROUND: Age-related macular degeneration (AMD) is a leading cause of vision loss. Photobiomodulation (PBM) offers a controversial approach for managing dry AMD, aiming to halt or reverse progression through mitochondrial activity modulation. However, the efficacy and clinical relevance of PBM as a potential approach for managing dry AMD remain debated. METHODS: We systematically searched PubMed, Embase, and Cochrane databases for randomized controlled trials (RCTs) comparing PBM versus a sham in patients with dry AMD. We performed trial sequential analysis (TSA) and minimal clinically important difference (MCID) calculations to assess statistical and clinical significance applying a random-effects model with 95% confidence intervals (CI). RESULTS: We included three RCTs comprising 247 eyes. The pooled analysis showed that PBM significant improved BCVA (MD 1.76 letters; 95% CI: 0.04 to 3.48) and drusen volume (MD -0.12 mm³; 95% CI: -0.22 to -0.02) as compared with a sham control. However, the TSA indicated that the current sample sizes were insufficient for reliable conclusions. No significant differences were observed in GA area. The MCID analysis suggested that the statistically significant results did not translate into clinically significant benefits. In the quality assessment, all studies were deemed to have a high risk of bias. CONCLUSION: This meta-analysis points limitations in the current evidence base for PBM in dry AMD treatment, with issues around small sample sizes. Statistically significant improvements do not translate into clinical benefits. The research underscores need for larger RCTs to validate PBM's therapeutic potential for dry AMD.

Choroidal nevus through a broader vision: Retinal imaging acquisition captured with Broad Line Fundus Imaging technology.

OBJECTIVE: To describe the peculiarities in imaging acquisition of fourteen patients with choroidal nevus using the Broad Line Fundus Imaging (BLFI) technology. METHODS: Single-center, retrospective, cross-sectional analysis. RESULTS: All images were acquired using the BLFI technology. We have found that choroidal nevus is undetectable in the blue channel (BC) (435-500 nm) and the green channel (GC) (500-585 nm). The only visible changes are related to the drusen, which appeared in BC and GC as light focal dots, correlated to the yellowish foci in the true-color image. On the red channel (RC) (585-640 nm), all lesions revealed the same pattern: a well-defined dark spot, with enhanced contrast, allowing the better visualization, measuring, and characterization of the nevus when compared with the other color channels, including the true-color imaging. CONCLUSION: BLFI application in choroidal nevus might be helpful at presentation, refining the diagnostic reliability, and monitoring, as it allows for better detection of alterations in the lesions. The peculiarities of the choroidal nevus are better assessed when using the RC due to its longer wavelength and deeper penetration in the retina and choroid.

Optical Coherence Tomography Angiographic Evaluation of Macular Vessel Density in Diabetic Macular Edema After Intravitreal Dexamethasone Implants: A Prospective Interventional Trial.

BACKGROUND AND OBJECTIVE: The goal of this study was to assess macular vascular density evolution, macular thickness, and functional outcomes after intravitreal dexamethasone implants for diabetic macular edema. PATIENTS AND METHODS: Vascular density was evaluated with optical coherence tomography (OCT) angiography in 21 eyes. Macular thickness was evaluated with structural OCT. Visual acuity and contrast sensitivity were evaluated before and after treatment, and these functional outcomes were analyzed for association with anatomic outcomes. Macular vessel density in the superficial capillary plexus was evaluated with OCT angiography and quantified in areas with no fluid, allowing a more accurate measurement and eliminating the segmentation bias in areas with intra-retinal fluid. Such a methodology was possible by positioning the scans only in areas with no fluid before and after the implant. The absence of fluid in these areas was confirmed by three experienced evaluators using both the B-scan and the en face. Visual acuity and contrast sensitivity were evaluated before and after treatment, and these functional outcomes were analyzed for association with anatomic outcomes. RESULTS: At 30, 60, and 90 days after implantation, there was improvement in macular perfusion in areas without fluid after intravitreal dexamethasone implantation, accompanied by reduced macular thickness and improved visual acuity (P < .001). However, there was no improvement in contrast sensitivity after treatment. CONCLUSIONS: Improved macular perfusion after treatment with intravitreal dexamethasone implantation may be associated with modulation of leukostasis, when the release of cytokines leads to capillary endothelial damage and obstruction of the micro-vasculature, leading to impaired capillary perfusion and ischemic damage. Despite the anatomical and functional findings demonstrated, further studies are needed to prove the relationship between the inflammatory mechanisms of diabetic macular edema and its relationship with macular perfusion and functional aspects. [Ophthalmic Surg Lasers Imaging Retina 2023;54(3):174-182.].

Multiple evanescent white dot syndrome (MEWDS) following inactivated COVID-19 vaccination (Sinovac-CoronaVac).

A 38-year-old woman presented with photopsias and progressive but painless loss of vision in her right eye. Of note, she had received the first dose of inactivated COVID-19 vaccine (Sinovac/China National Pharmaceutical Group) 2 weeks prior to the onset of symptoms. Ophthalmic evaluation revealed a wreath-like foveal pattern and multiple gray-white dots throughout the posterior pole associated with discrete vitreous inflammatory reaction. Multimodal imaging analysis confirmed a diagnosis of multiple evanescent white dot syndrome. The patient underwent treatment with corticosteroids and, over the following weeks, her visual acuity improved to standard pattern.

Effects of phosphodiesterase type 5 inhibitors on choroid and ocular vasculature: a literature review.

To provide information on the effects of phosphodiesterase type 5 (PDE5) inhibitors on choroidal vessels and central serous chorioretinopathy (CSC) and possible implications for development of exudative age-related macular degeneration (AMD). Two independent investigators conducted a qualitative review of PubMed to identify studies on the choroidal effect of PDE5 inhibitors in June 2019. The search used key words that included PDE5 inhibitors, sildenafil, tadalafil, vardenafil, choroid, choroidal flow, choroidal vessels, choroidal thickness, CSC, AMD or a combination. Only studies which assessed choroidal findings were included. Many ocular diseases are related to changes in choroidal thickness and perfusion. Patients with AMD, who have decreased choroidal perfusion, may manifest more severely diminished choroidal ability to deliver oxygen and other metabolites to the retina, leading to growth of neovascular tissue. As a result of this engorgement of the choroidal vasculature, some patients may have leakage across the retinal pigment epithelium (RPE) and accumulation of subretinal fluid, resulting in CSC. Transient visual symptoms, i.e., changes in color perception and increased light sensitivity, are well-known adverse effects, but there have been rare reports of vision-threatening ocular complications in users of PDE5 inhibitors, such as nonarteritic anterior ischemic optic neuropathy and cilioretinal artery occlusion. The choroid is a vascular tissue analogous in many respects to the corpus cavernosum, and PDE5 inhibitors may increase the choroidal thickness and perfusion. While it is intuitively obvious that thickness of the choroid alone does not guarantee better choriocapillaris oxygenation, it is a reasonable step towards ameliorating ischemia. These drugs have numerous physiologic effects on the choroid related to blood flow, such as clinical consequences in CSC and AMD.

Comparison of choroidal thickness in normal eyes and different ocular pathologies in a Brazilian population

Abstract Objective: To evaluate the choroidal thickness (CT) in healthy Brazilian subjects using spectral-domain optical coherence tomography (SD-OCT) and to compare with choroidal thickness measured in Brazilian patients with diabetic macular edema (DME), neovascular age-related macular degeneration (AMD) and high myopia. Methods: A retrospective analysis of spectral domain optical coherence tomography (SD-OCT) images of 181 Brazilian subjects. A total of 74 eyes were included in the normal control group, 50 eyes in the nvAMD group, 44 eyes in the DME group and 13 eyes in the high myopia group. CT was measured from the posterior edge of the retinal pigment epithelium (RPE) to the choroid/sclera junction at the fovea and at 500 μm intervals temporal and nasal to the fovea. All measurements were performed by two independent observers and were averaged for analysis. The statistical analysis and comparison were performed using Mann Whitney (unpaired t-test). Results: Seventy-four eyes from 74 patients with a mean age of 51.4 years were analyzed in the normal group with a mean nasal, subfoveal and temporal choroidal thickness measurements were 301.30 ± 12.86 μm, 311.61 ± 12.62 μm and 309.28 ± 12.28 μm respectively. All groups with disease demonstrated a statistically significant choroidal thinning when compared with matched-aged normal eyes. The mean reduction in the nvAMD group compared to normal were 60.65 μm nasally, 59.77 μm temporally and 56.59 μm at subfoveal position. In the DME group, the subfoveal reduction was 51.10 μm, 63.03 μm and 46.30 μm, nasally and temporally. The patients with high myopia presented the greatest reduction in CT compared to normal eyes, with a mean reduction of 159.9 nasal, 159.98 subfoveal and 154.65 at temporal. Conclusions: The present study evaluated choroidal thickness in Brazilian subjects, with intense miscegenation. The results demonstrated a statistically significant decrease of the choroidal thickness in all subtypes of chorioretinal disease. The small sample size in this study was a limitation. Additional research with a larger study population to better understand these findings.

Resumo Objetivo: Avaliar a espessura da coróide (EC) de indivíduos brasileiros saudáveis utilizando tomografia de coerência ótica do domínio espectral (TCO-DE) e compará-la à espessura da coroide de pacientes brasileiros com edema macular diabético (EMD), degeneração macular neovascular relacionada à idade (DMRI) e miopia alta. Metodologia: Análise retrospectiva de imagens de tomografia de coerência ótica de domínio espectral (TOC-DE) de 181 indivíduos brasileiros. Um total de 74 olhos foram incluídos no grupo controle normal; 50, no grupo DMRI; 44, no grupo EMD; e 13, no grupo com miopia alta. A EC foi medida a partir da borda posterior do epitélio pigmentar da retina (EPR) até a junção coróide/esclera na fóvea e de intervalos de 500 μm, temporal e nasal, à fóvea. Todas as medidas foram realizadas por dois observadores independentes e as médias foram calculadas para análise. A análise estatística e a comparação das ECs foram realizadas usando o teste Mann Whitney (teste t não pareado). Resultados: Setenta e quatro olhos de 74 pacientes com idade média de 51,4 anos foram analisados no grupo normal, o qual apresentou espessura coróide nasal, subfoveal e temporal média igual a 301,30 ± 12,86 µm, 311,61 ± 12,62 µm e 309,28 ± 12,28 µm, respectivamente. Todos os grupos com doença demonstraram afinamento de coroide estatisticamente significativo quando comparados a olhos normais pareados por idade. A redução média de EC no grupo DMRI em comparação ao normal foi de 60,65 μm por via nasal, 59,77 μm por via temporal e 56,59 μm na posição subfoveal. O grupo EMD apresentou redução de EC igual a 51,10 μm em posição subfoveal, 63,03 μm por via nasal e 46,30 μm por via temporal. Pacientes com miopia alta apresentaram a maior redução de EC em relação aos olhos normais; os valores de redução média obtidos foram 159,9 por via nasal, 159,98 em posição subfoveal e 154,65 por via temporal. Conclusões: O presente estudo avaliou a espessura da coróide de indivíduos brasileiros com intensa miscigenação. Os resultados demonstraram reducção estatisticamente significativa da espessura da coróide em todos os subtipos de doença coriorretiniana. O pequeno tamanho da amostra foi uma limitação deste estudo. Pesquisas adicionais com população maior de estudo deveriam ser realizadas para ajudar a entender melhor esses achados.

Short-term eplerenone for treatment of chronic central serous chorioretinopathy; a prospective study.

BACKGROUND: Increased mineralocorticoid activity is one of the plausible causes of chronic central serous chorioretinopathy (CSCR) and mineralocorticoid inhibitors such as eplerenone have been investigated as its potential therapy. This study investigates the short-term safety and efficacy of oral eplerenone in patients with chronic CSCR. PATIENTS AND METHODS: Prospective study of 13 eyes of 13 patients with the diagnosis of chronic CSCR. All patients received eplerenone 50 mg/day for 4 weeks. Enhanced depth imaging optical coherence tomography (OCT) was obtained. Best corrected visual acuity (BCVA), and OCT parameters including sub retinal fluid (SRF), choroidal thickness (CT) and central macular thickness (CMT), were measured manually. RESULTS: The mean SRF height decreased slightly at 1-month follow-up as compared to baseline, but the change was not statistically significant (94.18 ± 17.53 vs. 113.15 ± 18.69; p = 0.08). Subfoveal CT and CMT was significantly reduced as compared to baseline (6.6% [p = 0.002] and 7.05% [p = 0.04], respectively). The BCVA did not change significantly (20/28 vs. 20/30 [p = 0.16]). CONCLUSION: This study suggests that oral eplerenone may be used as a safe and potentially effective treatment in chronic CSCR, however there are minimal short-term effects on subretinal fluid or visual acuity therefore therapeutic trials longer than one month are necessary to test its benefits.Trial registration Clinicaltrials.gov identification number: NCT01822561. Registered 3/25/13, https://clinicaltrials.gov/ct2/show/study/NCT01822561.

Experimental model to evaluate the benefits of lutein to prevent retinal phototoxicity during pars plana vitrectomy surgery using xenon source light illumination in rabbits.

BACKGROUND: To evaluate the benefits of lutein in preventing retinal phototoxicity generated by xenon light sources during vitreoretinal surgery. METHODS: A prospective cross-sectional study in pigmented rabbit eyes exposed to different vitreoretinal surgery lighting simulations. Twenty Dutch-belted rabbits were divided into two groups exposed to two different xenon wavelength light sources filters (420 nm and 435 nm). In addition, two subgroups were administered with daily supplemental of 10 mg of Lutein systemically. Electroretinography (ERG), optical coherence tomography (OCT) and fluorescein angiography (FA) were performed before and after surgery to quantify the retinal damage. RESULTS: All animals submitted to the experiment presented some degree of phototoxicity independent of wavelength light filter used. Retinal damage was evident as the FA presented areas of hyperfluorescence, and the OCT depicted increased reflective areas of the inner and outer retinal layers, and RPE. ERG showed a diffuse reduction of the a and b waves amplitudes in all animals. CONCLUSION: Use of systemic administration of lutein showed no benefit to avoiding retinal phototoxicity generate to xenon light source using filters of 435 nm and 420 nm when comparing to the control group.

INTRAVITREAL ZIV-AFLIBERCEPT FOR NEOVASCULAR AGE-RELATED MACULAR DEGENERATION: 52-Week Results.

PURPOSE: To evaluate the 52-week safety and efficacy of intravitreal ziv-aflibercept in patients with neovascular age-related macular degeneration. METHODS: All patients received three monthly intravitreal injections of 0.05 mL of ziv-aflibercept (1.25 mg) followed by a pro re nata regimen. The best-corrected visual acuity and spectral domain optical coherence tomography were obtained at baseline and monthly. Full-field and multifocal electroretinograms were obtained at baseline and 4, 13, 26, and 52 weeks. For some full-field electroretinography parameters, we calculated the differences between baseline and 52 weeks and then compared those differences between treated and untreated fellow eyes. RESULTS: Fifteen patients were included and 14 completed the 52-week follow-up. The mean best-corrected visual acuity improved from 0.95 ± 0.41 (20/200) at baseline to 0.75 ± 0.51 (20/125) logarithm of the minimum angle of resolution at 52 weeks (P = 0.0066). The baseline central retinal thickness decreased from 478.21 ± 153.48 µm to 304.43 ± 98.59 µm (P = 0.0004) at 52 weeks. Full-field electroretinography parameters used to assess retinal toxicity after intravitreal injections (rod response and oscillatory potentials) remained unchanged during follow-up. The average multifocal electroretinography macular response in 5° showed increased N1-P1 amplitude and decreased P1 implicit time (P < 0.05). One patient presented with intraocular inflammation after the seventh intravitreal procedure. CONCLUSION: The results suggested that intravitreal ziv-aflibercept might be safe and effective for treating neovascular age-related macular degeneration. More patients and a longer follow-up are needed to confirm the long-term outcomes of intravitreal ziv-aflibercept.

Comparison of 577-nm Multispot and Standard Single-Spot Photocoagulation for Diabetic Retinopathy.

OBJECTIVE: To compare two different laser strategies of panretinal photocoagulation for diabetic retinopathy. METHODS: Single-center, randomized study including 41 eyes treated with 577-nm multispot laser with a 20-ms pulse duration (group 1) or a 532-nm single-spot laser with a 100-ms pulse duration (group 2). The outcomes included best-corrected visual acuity (BCVA) and imaging changes at baseline, 6 and 12 months, laser parameters, and results of subjective pain analysis. RESULTS: At 12 months, the treatments did not differ significantly in BCVA, central retinal thicknesses (CRTs), improved macular edema, vitreomacular interface changes, patient-reported pain scores, or angiographic responses. Group 1 had significantly fewer treatment sessions but used more laser spots (p < 0.001). CONCLUSION: The multispot laser required fewer applications with more spots delivered to compensate for lower fluency, showing similar patient tolerance to single-spot laser. Both groups maintained the initial visual acuities and CRTs; about 50% of cases had vitreomacular interface changes and improved macular edema, with similar angiographic improvements after 12 months.

VISUALIZATION OF CHOROIDAL NEOVASCULARIZATION USING TWO COMMERCIALLY AVAILABLE SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY DEVICES.

PURPOSE: To compare the sensitivity of detection and the measured size of choroidal neovascularization (CNV) on two commercially available spectral domain optical coherence tomography angiography (OCTA) devices, the Optovue RTVue XR Avanti with AngioVue and the Zeiss Cirrus HD-OCT with AngioPlex. METHODS: Patients with CNV lesions were imaged consecutively on both OCTA devices on the same day of their visit. 3 × 3 mm and 6 × 6 mm scans centered at the fovea were obtained. Two independent masked readers evaluated the OCTA images for CNV identification and its area measurements. RESULTS: No significant differences were observed between the 2 OCTA devices in CNV area measurements on their 3 × 3 mm and 6 × 6 mm scans. However, there was suboptimal performance of their automated segmentation algorithms as compared to manually adjusted segmentation for visualizing CNV lesions. CONCLUSION: There was no significant difference in the size of the CNV lesion as measured on either commercially available spectral domain OCTA device. Both devices were comparable in their detection of CNV lesions on manual adjustment of segmentation lines. However, their automated segmentation algorithms need improvement to allow for accurate measurement of CNV lesions for routine clinical application.

Choriocapillaris Hypoperfusion Artifact in OCT Angiography.

BACKGROUND AND OBJECTIVE: To illustrate how optical coherence tomography (OCT) angiography (OCTA) can be misinterpreted if not evaluated along with structural en face OCT to analyze the signal intensity. PATIENTS AND METHODS: Patients with different macular diseases associated with suspicious flow impairment in the choriocapillaris were recruited to be imaged on the RTVue XR Avanti device (Optovue, Fremont, CA) with the Angio Retina mode. En face OCT angiograms, structural en face OCT, and corresponding OCT B-scans with flow signal overlaid were compared to evaluate the correspondence of signal strength to areas of flow reduction in the choriocapillaris. RESULTS: Six eyes from six patients were enrolled. Macular lesions evaluated in this study included acute central serous chorioretinopathy, paracentral acute middle maculopathy, age-related macular degeneration, adult-onset foveomacular vitelliform dystrophy, and branch retinal vein occlusion. In all cases, areas of suspicious flow decrement in the choriocapillaris corresponded to hyporeflective areas in the intensity en face OCT. Thus, a precise confirmation of choriocapillaris flow impairment was not possible. CONCLUSION: It is essential to be aware of the importance of analyzing the structural image alongside with the flow image to interpret flow impairment. This is more important in subretinal pigment epithelial structures such as choriocapillaris and choroid. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:603-610.].

OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY AFTER PHOTOCOAGULATION OF TYPE 2 NEOVASCULARIZATION.

PURPOSE: To illustrate errors in the automated segmentation image analysis of optical coherence tomography angiography after laser photocoagulation therapy for Type 2 neovascularization. METHODS: This case report describes a patient with extrafoveal Type 2 neovascularization treated with argon laser photocoagulation evaluated before and after treatment by optical coherence tomography angiography. RESULTS: Disrupted retinal layers after laser photocoagulation therapy lead to segmentation errors. CONCLUSION: Images of optical coherence tomography angiography are prone to degradation by artifacts in cases in which there is disruption of the retinal layers. Clinicians must be aware of these errors because they can be misinterpreted as active Type 2 neovascularization. Improvement in optical coherence tomography angiography image analysis to minimize automated segmentation errors needs to be further explored.

OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY TO DETECT MACULAR CAPILLARY ISCHEMIA IN PATIENTS WITH INNER RETINAL CHANGES AFTER RESOLVED DIABETIC MACULAR EDEMA.

PURPOSE: To compare foveal vascular anatomy between patients with and without disorganization of retinal inner layers (DRILs) after resolved diabetic macular edema using optical coherence tomography angiography (OCTA). METHODS: Twenty-four eyes of 21 age- and sex-matched patients with resolved diabetic macular edema were included in this retrospective, cross-sectional study. All eyes were imaged with enhanced high-definition line or cross-line structural B scans and 3 × 3-mm OCTA scans. Optical coherence tomography B scans were analyzed for the presence of DRIL, and based on this, eyes were classified as either DRIL present or DRIL absent. The foveal avascular zone area on OCTA was compared between patients with and without DRIL. The foveal avascular zone area was correlated with visual acuity. RESULTS: Nine eyes with DRIL and resolved diabetic macular edema were compared with 15 control eyes without DRIL and resolved diabetic macular edema. Area of ischemia on OCTA scans corresponded to the area of DRIL as determined on OCT B scans. The foveal avascular zone area in full retina as well as superficial and deep retinal plexuses OCTA slabs were significantly larger in patients with DRIL as compared to those without DRIL (P = 0.005, P < 0.001, and P = 0.004, respectively). The larger foveal avascular zone in full retinal segmentation (r = 0.72, P = 0.03) and superficial plexus (r = 0.74, P = 0.02) were positively correlated with lower visual acuity. CONCLUSION: Optical coherence tomography angiography can visualize retinal ischemia in patients with and without DRIL. Correspondence of impaired blood flow with DRIL suggests that retinal ischemia and loss of normal vasculature contributes to DRIL.

Polypoidal Choroidal Vasculopathy on Swept-Source Optical Coherence Tomography Angiography with Variable Interscan Time Analysis.

PURPOSE: To use a novel optical coherence tomography angiography (OCTA) algorithm termed variable interscan time analysis (VISTA) to evaluate relative blood flow speeds in polypoidal choroidal vasculopathy (PCV). METHODS: Prospective cross-sectional study enrolling patients with confirmed diagnosis of PCV. OCTA of the retina and choroid was obtained with a prototype swept-source OCT system. The acquired OCT volumes were centered on the branching vascular network (BVN) and polyps as determined by indocyanine-green angiography (ICGA). The relative blood flow speeds were characterized on VISTA-OCTA. RESULTS: Seven eyes from seven patients were evaluated. Swept-source OCTA enabled detailed enface visualization of the BVN and polyps in six eyes. VISTA-OCTA revealed variable blood flow speeds in different PCV lesion components of the same eye, with faster flow in the periphery of polyps and slower flow in the center of each polyp, as well as relatively slow flow in BVN when compared with retinal vessels. BVNs demonstrated relatively faster blood flow speeds in the larger trunk vessels and relatively slower speeds in the smaller vessels. CONCLUSIONS: Swept-source OCTA identifies polyps in most, but not all, PCV lesions. This limitation that may be related to relatively slow blood flow within the polyp, which may be below the OCTA's sensitivity. VISTA-OCTA showed heterogeneous blood flow speeds within the polyps, which may indicate turbulent flow in the polyps. TRANSLATIONAL RELEVANCE: These results bring relevant insights into disease mechanisms that can account for the variable course of PCV, and can be relevant for diagnosis and management of patients with PCV.

Optical coherence tomography angiography artifacts in retinal pigment epithelial detachment.

OBJECTIVE: To describe optical coherence tomography angiography (OCTA) reflectance artifacts secondary to retinal pigment epithelial detachment (RPED). DESIGN: Retrospective review. METHODS: Four eyes from 4 subjects were included. Three presented with RPED and 1 eye was a normal control. Two eyes diagnosed with RPED and the normal eye were evaluated using en face OCTA centred at the fovea acquired using the RTVue XR Avanti (Optovue Inc). In the third eye with RPED, OCTA imaging was performed using a CIRRUS 5000 prototype modified to do OCTA imaging on a spectral domain OCT platform provided by Carl Zeiss Meditec, Inc. The segmented OCTA angiograms were overlaid to determine if the flow patterns seen at the edge of the RPEDs were due to reflectance from the inner retinal vessels, also known as "decorrelation tails." RESULTS: OCTA projection artifacts were noted when segmentation lines intersected with the boundary of the RPED. The overlaid segmented OCTA from the 3 RPED eyes imaged using each system revealed the same vasculature pattern at the edges of the RPED as that of the inner retina, demonstrating the "decorrelation tails" artifact, which caused the RPED to appear as a bright ring on the segmented OCTA. CONCLUSIONS: OCTA images are susceptible to various known artifacts. This series describes the impact of the projection artifact seen at the edges of an RPED that simulates appearance of flow but is actually due to reflectance of the inner retinal vasculature on the RPED.

Optical Coherence Tomography Features Preceding the Onset of Advanced Age-Related Macular Degeneration.

Purpose: Age-related macular degeneration (AMD) is a progressive disease with multifactorial etiology. There is a need to identify clinical features that are harbingers of advanced disease. We evaluated morphologic features of the retina and choroid on optical coherence tomography (OCT) to determine if they predict progression to advanced disease. Methods: Progressors transitioned from early or intermediate AMD to advanced disease (n = 40 eyes), and were matched on baseline AMD grade and follow-up interval to nonprogressors who did not develop advanced AMD (n = 40 eyes). Features of the neurosensory retina, photoreceptors, retinal pigment epithelium (RPE), and choroid were evaluated. Logistic regression was used to evaluate univariate associations between features and progression to overall advanced AMD, geographic atrophy (GA), and neovascular disease (NV). Multivariate associations based on stepwise regression models were also assessed. Results: Ellipsoid zone disruption was associated with progression to overall advanced AMD and NV (odds ratios [ORs]: 17.9 and 30.6; P < 0.001), with a similar trend observed for GA. Drusenoid RPE detachment, RPE thickening, and retinal pigmentary hyperreflective material were significantly associated with higher risk of progression to advanced AMD (ORs: 5.0-8.5) and NV (ORs: 10.8-17.2). Pigmentary hyperreflective material was associated with progression to GA (OR: 7.5, P = 0.009). Total retinal thickness, pigmentary hyperreflective material, nascent GA features, and choroidal vessel abnormalities were independently associated with progression to advanced AMD in a multivariate stepwise model. Conclusions: Abnormalities in the photoreceptors, retinal thickness, RPE, and choroid were associated with higher risk of developing advanced AMD. These findings provide insights into disease progression, and may be helpful to identify earlier endpoints for clinical studies.

Diagnosing Choroidal Neovascularization in Asymptomatic Individuals Using Optical Coherence Tomography Angiography.

Optical coherence tomography angiography (OCTA) is a noninvasive, rapid imaging technique that generates angiographic images without intravenous dye injections. Cross-sectional studies have described the presence of asymptomatic choroidal neovascularization (CNV) in patients with intermediate age-related macular degeneration (AMD). This case report describes the OCT features on longitudinal follow-up of a patient who started with unilateral asymptomatic CNV and eventually developed symptomatic exudative AMD. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:596-598.].

Visualization of changes in the foveal avascular zone in both observed and treated diabetic macular edema using optical coherence tomography angiography.

BACKGROUND: Central vision loss in diabetic retinopathy is commonly related to diabetic macular edema (DME). The objective of this study was to describe changes between consecutive visits on optical coherence tomography angiography (OCTA) of the foveal avascular zone (FAZ) in eyes with DME. METHODS: 20 eyes from 14 patients with DME were imaged on 2 successive clinic visits separated by at least 1 month. The mean interval between visits was 3.2 months. The only intervention used was intravitreal anti-VEGF in 11 eyes; the others were observed over time without treatment. Two different readers measured FAZ area using a pseudo-automated tool in comparison to a manual tracing tool. Qualitative changes in the appearance of the vasculature surrounding the FAZ were also recorded. The retinal capillary plexus was segmented into deep and superficial plexuses, and FAZ measurements were done on the superficial, deep, and summated plexuses. RESULTS: Pseudo-automated and manual measurements of FAZ area decreased significantly (p < 0.05) between visits in the deep, superficial, and summated plexuses. Qualitative analysis of vasculature surrounding the FAZ showed that most of the vascular changes (65%) over time were visible in the deep plexus, compared to 30 and 20% in the superficial and summated plexuses, respectively. CONCLUSIONS: The most significant differences in FAZ size over time were in the summated plexus (p < 0.001), while changes in FAZ appearance were most prominent in the deep plexus. Absolute decrease in FAZ size over visits was largest in the deep plexus. Our results demonstrate that OCTA can effectively be used to measure FAZ area in patients with DME, visualize qualitative changes in retinal vasculature, and visualize the segmentation levels at which these changes can be best appreciated. However, larger studies are needed to evaluate the reproducibility of manual and pseudo-automated measuring techniques.