Purpose: Reduction of visual acuity in patients with central retinal vein occlusion (CRVO) is often caused by macular edema and ischemia. The major causative factor for macular changes may be a disturbance in the macular microcirculation. The authors studied the perifoveal microcirculation in patients with central retinal vein occlusion to quantify the extent of circulatory deficiency in the macular circulation.
Methods: Twenty-four patients (8 men, 16 women) with recently diagnosed CRVO were included in this study. The following data were quantified: mean capillary blood velocity (CBV), foveal avascular zone (FAZ), and mean perifoveal intercapillary area (PIA).
Results: In patients with CRVO, the mean flow velocity was significantly reduced compared with healthy subjects (1.63 +/- 0.220 mm/sec vs. 2.89 +/- 0.41 mm/sec, P < 0.01). The FAZ and the mean PIA characterizing capillary density were significantly enlarged in CRVO (5548 +/- 1151 microm2 vs. 3872 +/- 529 microm2; P < 0.01).
Conclusions: The present study demonstrates that CRVO not only led to a decrease in capillary blood velocities, but also to an enlargement of perifoveal intercapillary areas in early stages of the disease.