Aberrant filling of the retinal vein on fluorescein angiography in branch and hemi-central retinal artery occlusion

Objective To study aberrant filling of the retinal vessels on fluorescein angiography (FA) images in patients with branch (BRAO) or hemi-central retinal artery occlusions (hemi-CRAO) and correlate with associated changes on optical coherence tomography (OCT). Methods Cases of acute BRAO or hemi-CRAO having FA and OCT images at presentation between June 2017 to May 2022 were included. Comparisons were made between the cases with and without aberrant filling of the retinal vessel. Results Thirty-nine eyes of 39 patients with acute retinal artery occlusions underwent FA and OCT imaging. Seven of the ten cases with either BRAO or hemi-CRAO showed aberrant filling of the retinal vein on FA. No case with CRAO showed aberrant filling on FA. The cases with aberrant filling showed a better presenting visual acuity and lesser severity of retinal ischemia on OCT. Shunts between the retinal artery in the unaffected region and the retinal vein in the affected segment was seen in two eyes. The remaining five eyes showed no arteriovenous anastomosis. Cases with aberrant filling had a better visual function even at the last visit. Conclusion Aberrant retinal vein filling across the horizontal median raphe in the affected region in BRAO or hemi-CRAO eyes had less severity of retinal ischemia and better presenting and final visual acuities. Reduced perfusion in retinal capillaries with altered retinal vascular anatomy or arteriovenous shunts could be probable reasons for the development of this FA finding. Presence of aberrant filling of the retinal vein could indicate better final visual prognosis.