Ultra-widefield Fluorescein Angiography Research Articles

RELATIONSHIP BETWEEN RETINAL HEMORRHAGE ON GREEN AND RED CHANNELS OF ULTRA-WIDEFIELD FUNDUS IMAGES AND RETINAL PERFUSION IN ACUTE BRANCH RETINAL VEIN OCCLUSION.

To explore the relationship between retinal hemorrhage in the green and red channels on ultra-widefield fundus images and the nonperfusion area (NPA) on ultra-widefield fundus fluorescein angiography in patients with acute branch retinal vein occlusion (BRVO). This was a retrospective cross-sectional study with 96 patients, including 46 with ischemic BRVO and 50 with nonischemic BRVO. Correlation analysis between green channel hemorrhage (GCH), red channel hemorrhage (RCH), and NPA was performed. Panretina was divided into posterior and peripheral areas. Ischemic BRVO showed significantly higher GCH% and RCH% than nonischemic BRVO in the peripheral regions (both P < 0.001), whereas no significant differences were observed in the panretinal and posterior areas (all P > 0.05). Significant correlations were found between NPA% in the panretinal and peripheral areas and the corresponding GCH% and RCH% (all P < 0.01). However, no significant correlation was observed between posterior NPA% and posterior GCH% or RCH% (both P > 0.05). In addition, peripheral GCH% and RCH% were related to panretinal NPA% (r = 0.506, P < 0.001; r = 0.558, P < 0.001). Retinal hemorrhage on ultra-widefield fundus image was significantly associated with NPA, providing insights for assessing retinal perfusion status in acute BRVO patients.

Relationship between ischemic index, leakage index, and macular edema in branch retinal vein occlusion.

To investigate the combined association of the ischemic index and leakage index with macular edema on ultra-widefield fluorescein angiography (UWFFA) in patients with branch retinal vein occlusion (BRVO). Retrospective image analysis study. The leakage index and ischemic index were calculated using Fiji after aligning early and late UWFFA images. Differences in the ischemic index, leakage index, and central macular thickness (CMT) between ischemic and non-ischemic BRVO were compared. Moreover, the association between the ischemic index, leakage index, and macular edema was analyzed. Eighty-three patients with BRVO were enrolled, including 53 non-ischemic BRVO and 30 ischemic BRVO patients. No significant differences were observed in leakage index and CMT between ischemic BRVO and non-ischemic BRVO (all P > 0.05). In all included patients, CMT correlated with the panretina and all subregion leakage indexes (all P < 0.01), but not with the ischemic index (all P > 0.05). In the ischemic BRVO group, CMT showed a correlation with the leakage index in several regions, but not with the ischemic index. After adjusting for the ischemic index and other clinical features, CMT remained significantly correlated with the leakage index in all regions. The leakage index may be a more effective biomarker for monitoring BRVO-associated macular edema compared to the ischemic index. Further follow-up studies are warranted to validate these findings.

Evaluation of Central and Peripheral Retinal Vascular Changes in the Fellow Eyes of Patients with Unilateral Retinal Vein Occlusions

To evaluate the subtle peripheral retinal and macular vascular changes in the fellow eyes of patients with unilateral retinal vein occlusion (RVO). This retrospective study included 53 patients with unilateral RVO and 44 age-matched controls. The frequency of peripheral retinal vascular pathologies in both eyes was evaluated using high quality ultra-wide field fluorescein angiography (UWFFA). Macular vascular density, flow area, and foveal avascular zone measurements from optical coherence tomography angiography (OCTA) were analyzed together with laser flare photometry values in patients and controls. Peripheral retinal vascular pathologies were detected on UWFFA in the fellow eyes of 36 (67.9%) patients. No significant central vascular pathologies were detected on OCTA and there was no significant difference in OCTA parameters between the fellow eyes and the controls. Flare values did not differ significantly between the control and the fellow eyes. Two thirds of the fellow eyes of unilateral RVO patients had subtle peripheral retinal vascular changes, while there was no significant microvascular change detected with OCTA in the macula. This suggests that vascular changes caused by systemic vascular disorders probably first start in the peripheral retina of the fellow eyes of patients with RVO.

Genetic and clinical characteristics of PROM1-related retinal degeneration in Korean

This scientific report aims to comprehensively describe the genetic and clinical characteristics of PROM1-related retinal degeneration in Korean patients. Medical records of patients diagnosed with retinal dystrophy who underwent comprehensive ophthalmologic examination and genetic testing at Samsung Medical Center between January 2016 and April 2023 were retrospectively reviewed. Genetic testing included targeted gene panel sequencing and Sanger sequencing, with diagnosis based on the presence of a “Likely Pathogenic” or “Pathogenic Variant” in the PROM1 gene, as determined by the ACMG criteria. The study identified seven patients from five unrelated families with PROM1-related retinal degeneration, all carrying the autosomal dominant variant PROM1 p.R373C; no other PROM1 gene variants were detected. All patients exhibited degenerative retinal area within the macula, with peripheral retinal degeneration observed in five patients. Substantial interfamilial and intrafamilial variability was observed in the extent of macular and peripheral degeneration. Ultra-widefield autofluorescence imaging and fluorescein angiography aided in the detection of mild peripheral degeneration in one case. In conclusion, the autosomal dominant variant PROM1 p.R373C constitutes a significant proportion of PROM1-related retinal degeneration cases in the Korean population. The observed clinical heterogeneity may suggests the potential influence of additional genetic, epigenetic, and environmental factors on disease phenotypes.

Month 60 Imaging Findings and Relationship to Treatment Outcomes Following Anti-VEGF Therapy for Macular Edema Due to Central or Hemi-Retinal Vein Occlusion

To evaluate imaging findings from SCORE2 participants through 60 months, to describe the degree of resolution or progression of these variables, and to correlate changes in these imaging findings to treatment outcomes such as visual acuity and the number of treatments administered. SCORE2 participants were followed for up to 60 months. Visual acuity, injection frequency and imaging tests color fundus photography (CFP), optical coherence tomography (OCT), and ultra-widefield fluorescein angiography [UWFA]) were performed throughout this period. Less than 6% of eyes had subretinal fluid at month 60. Disorganization of the retinal inner layers (DRIL) was the most likely finding to persist, present in 96% of eyes at baseline and unchanged at 95% at month 60. For UWFA, at baseline, there was a mean of 5.0% non-perfusion area (95% CI: 3.3%-6.8%) in the NETWORC grid with little change to month 60. For the Early Treatment Diabetic Retinopathy Study (ETDRS) grid, at baseline, there was a mean of 2.3% non-perfusion area (95% CI: 0.7%-3.9%) with little change to month 60. There was no correlation between any of the imaging variables at baseline and change in visual acuity to month 60 or in the number of injections following the variable treatment timeframe (month 12 to month 60). These analyses provide an anatomic explanation for persistent functional deficits many years following initial treatment. Clinical practice patterns should consider evaluation with these imaging tests to help explain persistent functional deficits in many eyes. Additionally, these 8 baseline imaging variables generally should not be relied on to predict visual acuity or intensity of treatment. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.

32-year-old diabetic patient with progressive vision loss and crystalline retinopathy.

To report the case of severe bilateral retinal vascular occlusion in a patient with hyperoxalosis and chronic renal failure. Observational case report. Medical and imaging records were retrospectively reviewed. The patient was imaged with ultra-widefield (UWF) fundus photography and fluorescein angiography (UWF-FA), cross sectional and en face spectral-domain optical coherence tomography (SD-OCT), and OCT angiography. A 32-year-old diabetic patient receiving peritoneal dialysis was referred because of severe vision loss. UWF color fundus photography showed diffuse sclerotic retinal vessels and diffuse intraretinal crystals in both eyes. UWF-FA illustrated near-complete retinal vascular occlusion and capillary wipe out in both eyes. SD-OCT demonstrated diffuse inner and middle retina thinning in both eyes and multiple intraretinal hyperreflective foci consistent with crystalline deposits in all retina layers of both eyes. OCT angiography revealed severe capillary and large vessel non-perfusion in the superficial and deep retinal capillary plexus of each eye. The serum oxalate levels were increased at 28 µmol/L (reference range < 2 µmol/L) and genetic testing was positive for a heterozygous mutation of the AGXT (Alanine-Glyoxylate Amino Transferase) gene that causes type 1 autosomal recessive primary hyperoxaluria. A diagnosis of hyperoxalosis causing severe retinal vascular occlusion was rendered. Hyperoxalosis was the result of multiple factors including heterozygous AGXT mutation, chronic renal failure insufficiently treated with peritoneal dialysis, and a diet high in oxalate. This case highlights the importance of ruling out retinal oxalosis in patients on peritoneal dialysis in order to initiate prompt hemodialysis and prevent severe retinal vascular occlusion.

Practical Utility of Widefield OCT Angiography to Detect Retinal Neovascularization in Eyes with Proliferative Diabetic Retinopathy

To assess the real clinical utility of widefield OCT angiography (WF-OCTA) for detecting retinal neovascularization (RNV) in eyes with proliferative diabetic retinopathy (PDR). A retrospective cross sectional study. Consecutive eyes clinically suspected of PDR by physicians at a tertiary eye center between March 2021 and November2022. All eyes underwent ultrawidefield fluorescein angiography (UWF-FA) (California, Optos) and WF-OCTA (S1, Canon) with a 23× 20 mm scan area. Two independent graders detected individual RNV lesions using UWF-FA and used them as the ground truth. Widefield OCT angiography images were first evaluated to determine whether the images successfully illustrated retinal vasculature, regardless of the image quality index or the presence of vitreous hemorrhage. The graders then identified the RNV lesions with WF-OCTA. We detected RNV by utilizing both the entire retinal slab, including flow signals in the retina, and the custom vitreoretinal interface slab, defined as flow signals from 20 μm below the internal limiting membrane (ILM) to 2000 μm above the ILM. We evaluated the applicability to real clinical practice by not correcting segmentation errors. The success rate of imaging and the detection rate of RNV using WF-OCTA. Initially, 69 consecutive patients who underwent UWF-FA were identified. Of these, 114 eyes from 57 (83%) patients underwent both UWF-FA and WF-OCTA. Of the 114 eyes, 108 (95%) produced gradable WF-OCTA images. Using UWF-FA, the graders identified 175 RNV lesions in 40 eyes. Widefield OCT angiography achieved a sensitivity of 95% and specificity of 88% for detecting eyes with RNV. At the level of individual RNV lesions, graders detected 156 RNV lesions with WF-OCTA, with 118 of these confirmed by UWF-FA (true positive). Among the 57 false-negative lesions, the primary causes were being out of the scan range (26 lesions) and segmentation errors (21 lesions). Widefield OCT angiography imaging had a high success rate, achieving a sensitivity of 95% and a specificity of 88% for detecting eyes with RNV in a real clinical setting. Despite a 67% detection rate for individual RNV lesions, WF-OCTA may serve as a valuable noninvasive method for RNV detection in eyes with diabetic retinopathy. Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Vascular abnormalities in fellow eyes of patients with unilateral coats’ disease

Coats’ disease is an idiopathic retinal vascular disorder, known to usually occur unilaterally; however, recent studies have highlighted vascular abnormalities in the fellow unaffected eyes. This retrospective study investigated the peripheral vascular features and macular vascular structure of unaffected fellow eyes in patients with unilateral Coats’ disease using multimodal imaging tools. We analysed images of patients, including bilateral ultra-widefield imaging, fluorescein angiography (FA), ultra-widefield FA, or standard fundus photography. Available bilateral optical coherence tomography angiography (OCT-A) images were used for macular vascular structure analysis. OCT-A parameters, including foveal avascular zone (FAZ), perfusion index, and vessel density (VD) in the superficial and deep capillary plexuses (SCP, DCP), were calculated using Image J software. The mean age at diagnosis was 34.5 ± 17.9 years. The mean final best-corrected visual acuity of the affected eyes was logMAR 0.78 ± 0.79, while that of the fellow eyes was logMAR 0.04 ± 0.12. Ten fellow eyes had microaneurysms (47.6%), two had tortuous vessel abnormalities (9.5%), and 11(52.4%) had abnormal vascular findings on FA. Although there was a trend towards larger DCP FAZ (1.201 ± 0.086 vs. 1.072 ± 0.226), and lower DCP VD (8.593 ± 1.583 vs. 10.827 ± 3.392) in the affected eyes as measured by the Cirrus machine, the difference was not statistically significant between affected and fellow eyes when measured using the Zeiss Cirrus machine (P = 0.686, P = 0.343, respectively). However, when measured with the Spectralis machine, DCP FAZ was larger in affected eyes (0.828 ± 0.426 vs. 0.254 ± 0.092, P = 0.002) and DCP VD was lower in affected eyes (6.901 ± 2.634 vs. 17.451 ± 7.207, P = 0.002) compared to the fellow eyes, while other parameters showed no significant variations. These findings indicate that there may be subtle vascular abnormalities primarily located in the peripheral regions of the unaffected fellow eyes in patients with unilateral Coats’ disease, while the macular microvasculature remains unaffected.

Diagnostic Role of Oral Fluorescein Angiography in Pediatric Ambulatory Clinics

Oral ingestion of fluorescein can be done in ambulatory pediatric clinics. We show that oral ultra-widefield fluorescein angiography is a non-invasive approach to rapidly diagnose and manage a diverse set of pediatric retinal vascular diseases.

Association between macrophage-like cell density and ischemia metrics in diabetic eyes

We previously showed that macrophage-like cells (MLCs) are increased in eyes with advanced diabetic retinopathy (DR). Here, we hypothesized that MLC density was correlated with ischemia using optical coherence tomography angiography (OCTA) and ultra-widefield fluorescein angiography (UWF-FA). Treatment-naïve diabetic eyes were prospectively imaged with repeated OCTA (average 5.3 scans per eye) and UWF-FA imaging. OCTA images were registered and averaged to generate a superficial capillary plexus (SCP), deep capillary plexus (DCP), and MLC slab. We calculated geometric perfusion deficit (GPD), vessel length density, and vessel density for the SCP and DCP. MLC density was quantified by two masked graders and averaged. Ischemia on UWF-FA was measured to generate a non-perfusion area (NPA) and index (NPI). Since MLC density was non-parametrically distributed, MLC density was correlated with ischemia metrics using Spearman correlations. Forty-five treatment-naïve eyes of 45 patients (59 ± 12 years of age; 56% female) were imaged. We included 6 eyes with no DR, 7 eyes with mild non-proliferative DR (NPDR), 22 moderate NPDR, 4 severe NPDR, and 6 PDR eyes. MLC density between graders was highly correlated (r = 0.9592, p < 0.0001). MLC density was correlated with DCP GPD (r = 0.296, p = 0.049), but no other OCTA ischemia metrics. MLC density was also correlated with UWF-FA NPA (r = 0.330, p = 0.035) and NPI (r = 0.332, p = 0.034). MLC density was correlated with total ischemia on UWF-FA and local DCP GPD. Since both UWF-FA and DCP non-perfusion are associated with higher risk for DR progression, MLC density could be another potential biomarker for DR progression.

Macular Thickness Is Associated with Persistent Avascular Retina in Patients with a History of Untreated Retinopathy of Prematurity

To evaluate the relationship between central macular thickness (CMT) and the presence of persistent avascular retina (PAR) in previously premature children. 17 4-8 year olds with a history of retinopathy of prematurity (ROP) screening were recruited, and underwent OCT and ultra-widefield fluorescein angiography (UWFFA). CMT was higher in PAR patients (p < 0.001). A central retina thickness above 260 μm had sensitivity/specificity of 95%/100% for detecting PAR. There may be an association between macular thickness as measured by OCT and the presence of PAR on UWFFA.

Treatment of Intermediate Uveitis-associated Retinal Vasoproliferative Tumors: A Case Series.

To report the use of combination intravitreal pharmacotherapy using anti-vascular endothelial growth factor (VEGF) and short and long-term corticosteroid implants for the treatment of retinal vasoproliferative tumors (VPT) associated with intermediate uveitis. Retrospective chart review of patients with VPT secondary to idiopathic intermediate uveitis that underwent combination intravitreal pharmacotherapy at a single center was performed. Multimodal imaging including ultrawide field color fundus photography, ultrawide field fluorescein angiography, and optical coherence tomography obtained before and after treatment were reviewed. Four eyes of 4 patients were treated with multiple injections of a combination of aflibercept, dexamethasone, and fluocinolone acetonide implants for VPT associated with intermediate uveitis. All 4 patients had improvement in visual acuity, intraocular inflammation, central macular thickness, and retinal vascular leakage, as well as regression of the VPT and reduction in lesion leakage on follow-up. Combination intravitreal anti-VEGF and corticosteroid implants may be a useful approach for the treatment of intermediate uveitis-associated VPTs and can lead to both functional and structural improvement.

Longitudinal Quantitative Ultrawidefield Angiographic Features in Diabetic Retinopathy Treated with Aflibercept from the Intravitreal Aflibercept as Indicated by Real-Time Objective Imaging to Achieve Diabetic Retinopathy Improvement Trial

To report longitudinal trends of quantitative ultrawidefield fluorescein angiography (qUWFA) biomarkers in the Intravitreal Aflibercept as Indicated by Real-Time Objective Imaging to Achieve Diabetic Retinopathy Improvement (PRIME) diabetic retinopathy (DR) clinical trial. Post hoc analysis of the PRIME prospective randomized DR clinical trial comparing intravitreal aflibercept treatment based on the DR severity score (DRSS) or quantitative leakage index for DR improvement (ClinicalTrials.gov identifier: NCT03531294). Patients were enrolled with a DRSS level of 47A to 71A and best-corrected visual acuity of 20/800 or better. Key exclusion criteria were previous intravitreal injection, panretinal photocoagulation, vitrectomy, central-involving macular edema, or vitreous hemorrhage. A previously validated, machine learning-based qUWFA analysis platform was used for panretinal leakage index assessment and differentiation of generalized and perivascular leakage phenotypes. Additionally, microaneurysm count and ischemic index were quantified in panretinal and macular regions. The trends in these biomarkers and therapeutic response were studied over 1 year. Longitudinal trends of qUWFA biomarkers. The impact of these qUWFA metrics on treatment response was assessed by studying their associations with time to 2-step DRSS improvement and number of treatment-free days. Forty eyes from 40 subjects with DR were enrolled. Lower baseline generalized leakage was noted in eyes that attained the 2-step DRSS improvement in < 16 weeks (1.9% vs. 2.8%; P= 0.026). Baseline macular perivascular-generalized leakage ratio had a significant correlation with the number of treatment-free days (r= 0.4; P= 0.012). At the end of 1 year, therapy significantly reduced the mean panretinal (3.9% vs. 5.8%; P= 0.002) and macular (6.2% vs. 12.2%; P= 0.008) generalized leakage indices compared with baseline, as well as the mean panretinal perivascular leakage index (1.5% vs. 2.3%; P= 0.002). The mean panretinal ischemic index demonstrated a small but likely clinically insignificant decrease from 12.5% at baseline to 11.6% at year 1 (P= 0.016). Down-trending leakage indices and microaneurysm counts were demonstrated over 1 year of anti-VEGF therapy. At baseline, DR eyes with lower generalized leakage responded to therapy more rapidly. Eyes with greater perivascular leakage relative to generalized leakage showed a longer-lasting anti-VEGF treatment response. Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Local ocular factors associated with the development of diabetic macular edema: an inter-eye study

To investigate local ocular factors associated with the development of diabetic macular edema (DME), we classified each eye of patients with unilateral DME as the DME eyes or the fellow eyes (without DME). We compared the clinical characteristics, optical coherence tomography (OCT), and OCT angiography (OCTA), ultra-wide field fundus photography, and angiography features of each eye. As a result, fifty-five patients with unilateral DME were enrolled. Although the diabetic retinopathy stage was not different between each group of eyes, DME eyes showed a higher prevalence of venous beading and a larger area of nonperfusion region than did fellow eyes (all P < 0.05). OCTA features of DME eyes also showed a larger foveal avascular zone in the deep capillary plexus and a lower vascular density in both the superficial and deep capillary plexuses (all P < 0.05). This study highlighted ocular features reflecting retinal ischemia, such as venous beading, area of nonperfusion region, and vascular density in the central retinal area, are associated with the development of DME. OCTA and ultra-wide field fluorescein angiography may be useful for evaluating the parameters of retinal ischemia and the risk of DME development.

Persistent Vascular Anomalies in Retinopathy of Prematurity Children: Ultrawide-field Fluorescein Angiography Findings until School Age.

To investigate vascular abnormalities, including persistent avascular retina (PAR), in a large cohort of patients with regressed or treated retinopathy of prematurity (ROP) through long-term follow-up until school age. Retrospective large cohort study. We included pediatric patients (< 18 years old) with a history of nontreated or treated ROP (treated with either photocoagulation or intravitreal injection [IVI]) and regularly followed up until2020. Upon enrollment, we categorized patients into 4 groups: prematurity, regressed ROP, and IVI and laser treatment ROP groups. All patients had undergone visual acuity examinations, OCT, and ultrawide-field fluorescein angiography. Percentage of eyes with PAR (greater than or equal to the area of 2 disc diameters from the ora serrata to vascular termini) and with vascular abnormalities in the peripheral and posterior retina. In total, we included 187 eyes of 95 patients. The prevalence of PAR was 0%, 33.33%, and 31.65% in eyes in the prematurity, regressed ROP, and IVI treatment groups, respectively (P<0.0001). There was no significant difference in the percentage of PAR eyes when comparing regressed ROP group (33.33%) with the IVI treatment group (31.65%). At least 1 type of vascular abnormality was noted until school age in all (100%) treated ROP eyes. Although multivariate analysis found a significant association between IVI treatment and PAR (odds ratio: 10.28, 95% confidence interval: 3.29-32.14) until the school age of 6 to 8 years old, there were no stage 3 eyes in the spontaneously regressed group, suggesting that stage 3 ROP in the IVI group could also drive the association. Approximately one-third of ROP eyes with spontaneous regression or IVI treatment still exhibit PAR when the child reaches school age. Several distinct vascular anomalies at the vascular-avascular juncture and within the vascularized retina can persist in these children. The clinical significance of these anomalies and the decision whether to treat them warrant further investigation to optimize their outcomes. The authors have no proprietary or commercial interest in any materials discussed in this article.

Peripheral and central retinal vascular changes in asymptomatic family members of patients with familial exudative vitreoretinopathy.

To evaluate the peripheral vascular changes and effects of these on macular microvasculature in asymptomatic family members of familial exudative vitreoretinopathy (FEVR) patients. This is a retrospective study including 61 eyes of asymptomatic family members of FEVR patients. Retinal abnormalities were assessed via ultra-widefield fluorescein angiography (UWF-FA) and optical coherence tomography angiography (OCTA). The eyes were grouped into 3: the first group comprised of eyes with normal findings on UWF-FA; the second group comprised of eyes with abnormal findings on UWF-FA but without any retinal ischemia; and the third group involved eyes with retinal ischemia or neovascularization. Best corrected visual acuity (BCVA) was 20/20 in all eyes. Forty eyes (65.6%) had abnormalities on UWF-FA. The most common feature was peripheral vascular looping, increased tortuosity, and anastomosis (63.9%). ODM/ODD ratio was higher in group 3 compared to groups 1 and 2. Deep foveal VD was lower in group 1 compared to groups 2 and 3. The mean FAZ area and perimeter were smaller in groups 2 and 3 compared to group 1. Even asymptomatic family members of FEVR patients may have significant peripheral retinal vascular abnormalities which may be associated with smaller optic disc, macular ectopia, and macular microvascular changes.

Non-invasive biomarkers for close activity monitoring in birdshot chorioretinitis: Optical coherence tomography angiography and beyond.

The purpose of the study was to identify non-invasive imaging biomarkers potentially useful for close activity monitoring in birdshot chorioretinitis (BSCR). Cross-sectional study of BSCR eyes included as per Levinson's and/or SUN criteria. Eyes were blindly classified into active or inactive groups per clinical inflammatory parameters, ultra-widefield (UWF) pseudocolour images, UWF fluorescein angiography (FA) and macular optical coherence tomography (OCT) cube. Qualitative and quantitative OCT and OCT-angiography (OCT-A) parameters at the fundus, superonasal and inferonasal fields were compared between active and inactive eyes. Thirty consecutive BSCR patients (60 eyes) were analysed. 28 eyes (46.66%) were from women and the overall mean age was 59.7 ± 12.3 years. Active eyes showed an abnormal retinal thickening at inferonasal field (nasal retinal thickness) and a higher averaged thickened retinal index (ATRI) (72.36 active vs. 20.12 inactive, p < 0.0001). A significant moderate correlation was observed between ATRI and FA scores (r = 0.259, p = 0.022). Macular vascular loops were more frequent in the superficial vascular plexus of OCT-A in the active eyes (p = 0.028). The vascular perfusion index tended to be higher in all subfields of active eyes but did not reach statistical significance. Multimodal imaging could be key to discerning activity in BSCR eyes. Higher ATRI and the presence of vascular loops in the superficial plexus are potential non-invasive activity biomarkers for the close monitoring of BSCR.

Distribution of leakage index using ultra-widefield fluorescein angiography in patients with non-ischemic branch retinal vein occlusion and its association with macular edema

BackgroundTo investigate the distribution of leakage index in patients with non-ischemic branch retinal vein occlusion (BRVO) and its correlation with the severity of macular edema. MethodsRetrospective observational study. Forty-five eyes of 45 patients with BRVO were included. Late ultra-widefield fluorescein angiography images of the affected eyes were processed and analyzed for their leakage index using Fiji software. The visible panretinal area was further divided into the peri‑macular area (PMA), near-peripheral area (NPA), midperipheral area (MPA), and far-peripheral area (FPA). The relationship between the leakage index and central retinal thickness (CMT) was analyzed for the panretina and each subregion. ResultsThe median (interquartile range) leakage indexes of the panretina, PMA, NPA, MPA, and FPA were 5.532% (7.667%), 23.127% (26.073%), 8.303% (16.807%), 1.588% (6.204%), and 0.408% (2.215%), respectively, with a mean CMT of 552.800 ± 183.335 μm. The CMT was positively correlated with the leakage index in the panretina, PMA, NPA, MPA and FPA (r = 0.468, 0.426, 0.463, 0.447, 0.320, respectively; all p < 0.05). ConclusionsThe leakage index in non-ischemic BRVO patients is associated with macular edema severity. The leakage index has the potential to be a useful indicator for monitoring and guiding treatment of macular edema in BRVO patients.

Clinical utility of ultra-widefield fluorescein angiography and optical coherence tomography angiography for retinal vein occlusions.

Retinal vein occlusions (RVOs) are the second most common retinal vascular disease after diabetic retinopathy, and are a significant cause of visual impairment, especially in the elderly population. RVOs result in visual loss due to macular ischemia, cystoid macular edema (CME), and complications related to neovascularization. Vascular assessment in RVOs traditionally relies on standard fluorescein angiography (FA) for assessment of macular and retinal ischemia, which aids in prognostication and guides intervention. Standard FA has significant limitations-it is time-consuming, requires invasive dye administration, allows for limited assessment of the peripheral retina, and is usually evaluated semi-qualitatively, by ophthalmologists with tertiary expertise. More recently, the introduction of ultra-widefield FA (UWF FA) and optical coherence tomography angiography (OCTA) into clinical practice has changed the tools available for vascular evaluation in RVOs. UWF FA allows for evaluation of peripheral retinal perfusion, and OCTA is non-invasive, rapidly-acquired, and provides more information on capillary perfusion. Both modalities can be used to provide more quantitative parameters related to retinal perfusion. In this article, we review the clinical utility and impact of UWF FA and OCTA in the evaluation and management of patients with RVOs.

Deep learning for automated detection of neovascular leakage on ultra-widefield fluorescein angiography in diabetic retinopathy

Diabetic retinopathy is a leading cause of blindness in working-age adults worldwide. Neovascular leakage on fluorescein angiography indicates progression to the proliferative stage of diabetic retinopathy, which is an important distinction that requires timely ophthalmic intervention with laser or intravitreal injection treatment to reduce the risk of severe, permanent vision loss. In this study, we developed a deep learning algorithm to detect neovascular leakage on ultra-widefield fluorescein angiography images obtained from patients with diabetic retinopathy. The algorithm, an ensemble of three convolutional neural networks, was able to accurately classify neovascular leakage and distinguish this disease marker from other angiographic disease features. With additional real-world validation and testing, our algorithm could facilitate identification of neovascular leakage in the clinical setting, allowing timely intervention to reduce the burden of blinding diabetic eye disease.