Abstract
Purpose: :
To assess the differences in associations of ocular perfusion pressure (OPP), retinal and retrobulbar blood flow between male and female with primary open angle glaucoma (OAG).
Methods: :
116 patients (age 66.9 +/- 10.9 years, 70 females) with OAG participating in the Indianapolis Glaucoma Progression Study were assessed for OPP, retinal microcirculation and the retrobulbar blood flow. Confocal scanning laser Doppler flowmetry was used to measure peripapillary retinal capillary blood flow. Color Doppler imaging (CDI) was used to measure systolic (PSV) and diastolic (EDV) blood flow velocities and vascular resistance in the retrobulbar blood vessels including the ophthalmic (OA), central retinal (CRA) and nasal and temporal short posterior ciliary arteries (N/T PCA). Bivariate Spearman correlation and multivariate linear regression analysis were performed.
Results: :
In female OAG patients, the inferior retinal capillary flow was associated with OPP (r=0.246, P=0.044). In men, both superior and inferior sector retinal blood flow were associated with OPP (r=-0.402, P=0.006 and r=-0.357, P=0.016, respectively). There was no statistically significant association between OPP with the retrobulbar blood vessel flow velocities in men OAG patients but there was an association between OA and TPCA PSV and OPP in women OAG patients (r=0.290, P=0.015 and r=0.357, P=0.002, respectively), an effect which was independent of age in the multivariate analysis. In female OAG patients, multivariate regression showed no statistically significant effect of any variable on the superior retinal capillary blood flow, with CRA PSV as a sole predictor to the inferior retinal sector (partial rho=0.302, P=0.015) and in male OAG patients, superior sector retinal capillary blood flow was independently associated with IOP (partial rho=-0.371, P=0.016) and OPP (partial rho=-0.456, P=0.002) with a trend of association with OPP in the inferior retina (partial rho=-0.301, P=0.053).
Conclusions: :
In females only, there was a linear association between the retrobulbar blood flow and the retinal microcirculation. OPP was associated with the retinal flow in the inferior retinal sector only in females. Male and female OAG patients may differ in their vascular autoregulation in response to changes in OPP.
Keywords: blood supply • retina • optic nerve