Angiographic Characteristics in Mild Familial Exudative Vitreoretinopathy with Genetically Confirmed Autosomal...

Area of Science:

• Ophthalmology
• Genetics
• Medical Imaging

Background:

• Familial exudative vitreoretinopathy (FEVR) is a genetic disorder affecting retinal vascular development.
• Autosomal dominant (AD) forms of FEVR are often linked to mutations in Norrin/β-catenin pathway genes.
• Understanding the angiographic features of mild FEVR is crucial for accurate diagnosis and genetic counseling.

Purpose of the Study:

• To characterize the ultra-widefield fluorescein angiographic (UWFA) features in patients with mild autosomal dominant (AD) familial exudative vitreoretinopathy (FEVR).
• To identify specific UWFA biomarkers associated with pathogenic variants in FEVR-related genes (Norrin/β-catenin).

Main Methods:

• Observational case series of 37 patients with mild FEVR and pathogenic gene variants, compared to 32 controls.
• Ultra-widefield fluorescein angiography (UWFA) images were analyzed for peripheral vascular changes.
• Receiver operating characteristic (ROC) curves were used to determine the cut-off for clinically significant avascular retina (csAR).

Main Results:

• Patients with AD-FEVR showed significantly higher frequencies of V-shaped vascular notches (69%), brushy vascular ends (78%), csAR (83%), and vascular stain (70%) compared to controls.
• A combination of V-shaped vascular notches, brushy vascular ends, and csAR demonstrated high sensitivity (82.8%) and specificity (98.3%) for AD-FEVR.
• Loop vessels/anastomosis were less frequent in patients (39%) than controls (73%).

Conclusions:

• The combination of V-shaped vascular notch, brushy vascular ends, and csAR serves as a reliable biomarker for identifying patients with AD-FEVR carrying Norrin/β-catenin gene variants.
• These UWFA findings facilitate more accurate genetic segregation analysis within FEVR families.
• Improved diagnostic biomarkers enhance genetic counseling for individuals and families affected by FEVR.