Fluorescein leakage of the optic disc: time course in primary open-angle glaucoma

To identify and quantify the time course of fluorescein leakage of the optic nerve head in primary open-angle glaucoma (POAG) and controls.

Twenty patients with POAG (aged 58 +/- 10 years) and 14 controls (aged 51 +/- 12 years, p = 0.07) were included in a prospective study. Fluorescein leakage of the optic disc was quantified using digital image analysis. A new leakage ratio (fluorescence of the optic disc divided by fluorescence of the surrounding retina) was defined and fluorescein leakage was quantified at 7-8, 9-10, 11-12, and 13-14 min after injection of 2.5 cc sodium fluorescein (10%).

The fluorescein leakage exhibited a significantly different time course with higher leakage ratio values in POAG compared to controls (7-8 min: 1.24 +/- 0.32 vs 1.16 +/- 0.12; 9-10 min: 1.37 +/- 0.37 vs 1.19 +/- 0.1; 11-12 min: 1.38 +/- 0.36 vs 1.24 +/- 0.13; 13-14 min: 1.44 +/- 0.36 vs 1.27 +/- 0.13; p = 0.004). The change in optic disc fluorescence from 7-8 min to 9-10 min was significantly higher in POAG compared to controls (0.13 +/- 0.09 vs 0.03 +/- 0.07; p = 0.002).

The time course of fluorescein leakage is significantly different in POAG compared to controls. This might reflect damage of the optic disc vasculature related to increased vascular permeability.