Abstract
Abstract: :
Purpose: To assess changes to the foveolar choroidal blood flow (FCBF)characteristics and potential for visual recovery in patients with central retinal vein occlusions (CRVO). Methods: A prospective series of six patients who presented with non–ischemic central retinal vein occlusions, confirmed with fluorescein angiography, and a seventh patient who presented with an ischemic central vein occlusion were evaluated with laser doppler flow to assess foveolar choroidal blood flow and correlate with visual recovery. Results: : A total of seven patients with CRVOs were evaluated with a mean age of 51.7 years (range 15–85 years) including four men and three women. Four left eyes and three right eyes were affected. The patients with non–ischemic CRVOs presented within 6 weeks (average time to presentation 2.9 weeks) of decreased vision with visual acuity of 20/400 or better (average 20/121) at the time of presentation. The foveolar choroidal blood flow characteristic of the affected eyes with non–ischemic CRVO demonstrated decreased blood velocity by 44.9%, decreased blood volume by 47.5%, and decreased blood flow by 63.5% compared to the unaffected eye. The patient with the ischemic CRVO in contrast to the sub–group that had non–ischemic CRVOs had much more severely affected foveolar choroidal blood flow characteristics with velocity decreased by 96%, volume decreased by 80.5% and flow decreased by 99.25%. The ischemic CRVO patient's FCBF and visual acuity (count fingers vision) did not change significantly at follow–up 3 weeks later. In contrast, in three patients followed longitudinally for 2–4 weeks following a non–ischemic CRVO, vision improved from a mean of 20/183 (20/70–20/400) to 20/48 (20/20–20/70) with blood flow characteristics also improving dramatically with velocity improving by 24.6%, volume improving by 83.9%, and flow improving by 97%. Conclusions: CRVO patients with severely depressed FCBF characteristics(> 80–99.25%) appear to have poor visual recovery as well as poor recovery of choroidal blood flow in the short term. In contrast, CRVO patients with moderate depression of the FCBF characteristics by 50–60% appear to have improved visual function and normalization of the FCBF within several weeks in the absence of significant macula edema. The foveolar choroidal blood flow may prove to be a useful adjunct in evaluating and following patients with central retinal vein occlusion and predicting their potential for visual recovery.
Keywords: imaging/image analysis: clinical • vascular occlusion/vascular occlusive disease • macula/fovea