Wide-Field Fluorescein Angiography in the Diagnosis and Management of Retinal Vein Occlusion: A Retrospective Single-Center Study

Artificial intelligence-based extraction of quantitative ultra-widefield fluorescein angiography parameters in retinal vein occlusion

OBJECTIVE

To examine the association between quantitative vascular parameters extracted from intravenous fluorescein angiography (IVFA) and baseline clinical characteristics of patients with retinal vein occlusion (RVO).

METHODS

Our prospective single-centre study in Toronto, Canada, recruited patients with a diagnosis of macular edema secondary to RVO presenting with a central macular thickness (CMT) ≥310 μm from 2017 to 2023. IVFA images were captured using an ultra-widefield scanning laser ophthalmoscope and processed using the artificial intelligence-based RETICAD system to extract quantitative measurements of blood flow, perfusion, and blood-retinal barrier (BRB) permeability. Univariable and multivariable regression models were used to investigate associations between quantitative IVFA parameters and baseline best-corrected visual acuity (BCVA), CMT, and macular volume.

RESULTS

The study included 41 eyes from 41 RVO patients. In the multivariable analysis, BRB permeability was significantly associated with both CMT (p < 0.001) and macular volume (p = 0.005). Subgroup analyses revealed that in central RVO patients, central BRB permeability remained significantly associated with CMT (p = 0.022) and macular volume (p = 0.010); however, there was no association with BCVA (p = 0.921). In branch RVO patients, central BRB permeability was significantly associated with BCVA (p = 0.006) and CMT (p = 0.009), but not with macular volume (p = 0.723). Additionally, both central and peripheral BRB permeability were significantly higher in patients with RVO compared to healthy controls (p < 0.001).

CONCLUSIONS

Our investigation reveals novel associations between baseline clinical characteristics and quantitative IVFA parameters in RVO patients, which may serve as clinically relevant biomarkers. Future studies should explore these associations in diverse RVO patient populations with extended follow-up.

Automated interpretation of retinal vein occlusion based on fundus fluorescein angiography images using deep learning: A retrospective, multi-center study

Purpose

Fundus fluorescein angiography (FFA) is the gold standard for retinal vein occlusion (RVO) diagnosis. This study aims to develop a deep learning-based system to diagnose and classify RVO using FFA images, addressing the challenges of time-consuming and variable interpretations by ophthalmologists.

Methods

4028 FFA images of 467 eyes from 463 patients were collected and annotated. Three convolutional neural networks (CNN) models (ResNet50, VGG19, InceptionV3) were trained to generate the label of image quality, eye, location, phase, lesions, diagnosis, and macular involvement. The performance of the models was evaluated by accuracy, precision, recall, F-1 score, the area under the curve, confusion matrix, human-machine comparison, and Clinical validation on three external data sets.

Results

The InceptionV3 model outperformed ResNet50 and VGG19 in labeling and interpreting FFA images for RVO diagnosis, achieving 77.63%-96.45% accuracy for basic information labels and 81.72%-96.45% for RVO-relevant labels. The comparison between the best CNN and ophthalmologists showed up to 19% accuracy improvement with the inceptionV3.

Conclusion

This study developed a deep learning model capable of automatically multi-label and multi-classification of FFA images for RVO diagnosis. The proposed system is anticipated to serve as a new tool for diagnosing RVO in places short of medical resources.

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.

Case Report: Recurrent retinal vein occlusion as the first clinical manifestation of systemic lupus erythematosus in a male patient

Systemic lupus erythematosus (SLE) is a chronic, autoimmune disease characterized by widespread clinical manifestations and immunological disorders. A myriad of ocular manifestations can be seen in patients with SLE. The most vision-threatening complication is vaso-occlusive retinopathy including retinal vein occlusion (RVO). RVO associated with SLE is well described in the literature and its association with antiphospholipid antibodies is recognized. However, RVO as the initial manifestation of SLE is scarcely reported.

Herein, we report the first case of recurrent RVO as the revealing manifestation of SLE in a 40-year-old male patient. He had two consecutive episodes of decreased vision. Ophthalmologic examination disclosed a branch retinal vein occlusion the first time and a central retinal vein occlusion the second time. The diagnosis of SLE was established based on clinical and immunological criteria. He was prescribed antiplatelet therapy, hydroxychloroquine at 5.5 mg/kg/day, and intravitreal anti-vascular endothelial growth factor (VEGF) antibodies regimen. He slowly improved under treatment.

Predictors of visual recovery in patients with macular edema secondary to central retinal vein occlusion after treatment with Conbercept

Background

The use of Spectral domain optical coherence tomography (SD-OCT) to evaluate the predictors of visual acuity-recovery in patients treated with conbercept for macular edema (ME) secondary to central retinal vein occlusion (CRVO) has rarely been seen. We collected 26 CRVO-ME patients with different OCT measures at 6 months follow-up to identify the factors that are most strongly correlated with the best-corrected visual acuity (BCVA) post-treatment in CRVO-ME patients treated with conbercept.

Purpose

To evaluate the effectiveness of intravitreal conbercept injections for the treatment of CRVO-ME and to determine the major predictors of best-corrected visual acuity (BCVA) post-treatment.

Methods

A retrospective study methodology was used. Twenty-six eyes from 26 patients with CRVO-ME were enrolled in the study. After an initial intravitreal injection of conbercept (0.5 mg/0.05 ml), monthly injections for up to 6 months were given following a 1 + PRN (pro re nata) regimen. Data collected at monthly intervals included measurements of the logMAR BCVA, central subfield thickness (CST), macular volume (MV), photoreceptor layer thickness (PLT), outer nuclear layer thickness (ONLT), and the disrupted ellipsoid zone (DEZ). The correlation between BCVA, before and after injections, and each of CST, MV, PLT, ONLT, DEZ was analyzed.

Results

The logMAR BCVA in months 3 and 6 post-injection was significantly improved relative to the baseline. In this same period the CST, MV, PLT, ONLT and DEZ were also significantly improved relative to the baseline. There was a negative correlation between PLT and logMAR BCVA at months 3 and 6 after treatment (r = − 0.549, P < 0.001; r = − 0.087, P < 0.001).

Conclusion

Intravitreal injection of conbercept is an effective treatment for CRVO-ME. With 6 months of follow-up, logMAR BCVA and CST, MV, PLT, ONLT, DEZ improved. PLT was negatively correlated with the visual function in CRVO-ME patients after conbercept treatment, which may be a predictor of vision recovery in patients with CRVO-ME.