Venous blood flow alterations in glaucoma patients

To evaluate the correlation between retinal venous blood flow parameters and glaucomatous visual field damage in a retrospective analysis.

Fifty-five (24 male, 31 female) glaucoma patients, under intraocular pressure (IOP) reducing treatment, aged (mean ± SD) 69 ± 10 years, 29 with primary open-angle and 26 with normal-tension glaucoma, were evaluated with regard to the correlation between IOP, color Doppler retinal venous blood flow velocity and glaucomatous damage.

Univariate regression analysis disclosed statistically significant correlations of the visual field index MD with age, IOP and venous blood flow (p ≤ 0.026 for each parameter). A mixed linear effects model disclosed a significant correlation of MD with age, IOP and venous blood flow (p ≤ 0.002 for each parameter), but not with sex, side (right eye versus left eye) and diagnosis (primary open-angle glaucoma versus normal-tension glaucoma). Finally, interocular difference (right eye vs. left eye of the same patient) in MD correlated with interocular differences in venous blood flow velocities (p < 0.001), but not with interocular differences in IOP.

Glaucomatous damage correlated negatively with retinal venous blood flow velocity, be it between subjects or between eyes within individuals. This study is limited by its cross-sectional design, and it is not possible to draw any conclusion with regard to the origin of the correlations.