Novel angiographic findings in Susac syndrome identified by ultra-widefield imaging technology

Abstract

 

Purpose

 

Susac syndrome is a rare condition characterized by the clinical triad of encephalopathy, branch retinal artery occlusions (BRAO) and hearing loss, most commonly identified in young white women. Ultra-widefield fluorescein angiography (FA) is an emerging technology that allows for visualization of the perfusion of the retinal periphery. This study evaluates novel angiographic features of the retinal periphery in Susac syndrome.

 

Methods

 

Retrospective, observational consecutive case series referred to the Cleveland Clinic Foundation International Susac Clinic and Cole Eye Institute for management of Susac syndrome. All patients underwent comprehensive ophthalmic exam and ultra-widefield FA with the Optos 200Tx system. Recent standard fluorescein angiograms obtained prior to evaluation at Cole Eye Institute were compared to the ultra-widefield FA when available.

 

Results

 

Four patients were identified with Susac syndrome and concurrent ultra-widefield FA. Novel peripheral angiographic findings included fluorescein column segmentation in both arteries and veins, large areas of early capillary dropout and peripheral non-perfusion, and ischemic/proliferative retinopathy changes. Peripheral segmentation of the fluorescein column was associated with delayed venous filling and late hyperfluorescence of both arteriolar and venous vasculature. All patients appeared to demonstrate normal choroidal filling. 2 of 8 eyes had macular involving BRAOs. 7 of 8 eyes had areas of capillary dropout or non-perfusion. 2 of 8 eyes had peripheral neovascularization. In comparison with recent standard angiograms (3 patients), all 6 eyes had retinal vascular changes visible on ultra-widefield angiography that were not seen on standard angiography images.

 

Conclusions

 

Susac syndrome has been typically characterized by recurrent branch retinal artery occlusions predominantly in the posterior pole. This study demonstrates the value of ultra-wide field angiography in the evaluation and diagnosis of patients with Susac disease. Additionally, it shows that the abnormality is panretinal in distribution with significant vascular occlusive disease in the far periphery not visible on standard angiography.

 

 

 

Keywords: 749 vascular occlusion/vascular occlusive disease • 550 imaging/image analysis: clinical