Optic Disc Microhemorrhage in Primary Open-Angle Glaucoma: Clinical Implications for Visual Field Progression.

Abstract

To establish the existence of minute-sized optic disc hemorrhage (DH; i.e., optic disc microhemorrhage [micro-DH]) in primary open-angle glaucoma (POAG) and to evaluate its clinical implications for glaucoma progression. Retrospective analysis of prospectively collected data. POAG patients with macro-DH who had met the following conditions were included: follow-up period 7 years or longer (at least 3 years before and at least 4 years after the date of first macro-DH), and more than nine reliable VF results. Micro-DH was defined as a less than 0.01-mm2 area DH that is undetectable on conventional stereo disc photography (SDP) but can be discriminated by enhanced SDP. SDPs were enhanced by customized image-compensation software. Each enhanced image was evaluated to determine the presence of micro-DH. VF progression was confirmed by standard automated perimetry's guided progression analysis. Among the 107 POAG eyes with macro-DH, micro-DH was detected prior to macro-DH in 39 (36.4%), the median time lag being 13.6 months. Over the course of the mean 7.1 ± 0.8-year follow-up period, 40 of 107 eyes showed VF progression: 21 (53.8%) of the 39 eyes of the micro-DH positive group and 19 (27.9%) of the 68 eyes of the micro-DH-negative group (P = 0.008). In the micro-DH-positive group, the cumulative VF-progression probability was significantly greater (P = 0.001), and the overall VF-deterioration rate was much faster (-1.01 ± 0.58 vs. -0.78 ± 0.49 dB/year, P = 0.029). Micro-DH was found prior to macro-DH detection in a significant proportion of POAG patients; micro-DH, moreover, was associated with earlier and faster VF progression.