Increased choroidal blood flow velocity with regression of unilateral acute idiopathic maculopathy

The pathogenesis of unilateral acute idiopathic maculopathy (UAIM) is unknown. The aim of this study was to quantitatively examine changes in choroidal circulation hemodynamics in patients with UAIM.

This was a retrospective observational case-series which included five eyes of four patients with UAIM. All UAIM eyes and the fellow eyes in remaining three patients were studied using laser speckle flowgraphy (LSFG) to evaluate the mean blur rate (MBR), a quantitative index of relative blood flow velocity. The changes in MBR between the initial visit and after 1 and 3 months were statistically analyzed. Subfoveal choroidal thickness was measured in three UAIM eyes by enhanced depth imaging optical coherence tomography.

The mean logMAR value of best-corrected visual acuity in the UAIM eyes significantly improved (P = 0.04) with recovery of outer retinal morphology. The average MBR of the UAIM eyes significantly increased at 1 (+21.7% baseline value; P = 0.003) and 3 months (+32.5% baseline value; P = 0.001), whereas the fellow eyes did not show this tendency. The mean values of subfoveal choroidal thickness decreased with time (316.0 µm at baseline, 186.6 µm at 1 month, and 167.3 µm at 3 months).

These results reveal that there is a significant elevation of choroidal blood flow velocity and substantial reduction of choroidal thickness with regression of UAIM, suggesting that impaired choroidal circulation may be involved in the pathogenesis of UAIM.