Abstract
Purpose: :
To evaluate the correlation between choroidal circulation with parapapillary and retrobulbar circulation in normal subjects, glaucoma suspects and open angle glaucoma (OAG) patients.
Methods: :
The study included one randomly selected eye from 21 normal subjects, 30 glaucoma suspects based on optic disc appearance and 22 OAG patients that were included after the 15 day medication washout period. The pulsatile ocular blood flow (POBF), which represents choroidal blood flow, was measured using Blood Flow Analyzer whereas mean parapapillary blood flow (MBF) and retrobulbar blood flow velocity was measured using Heidelberg Retinal Flowmeter and color Doppler Imaging respectively. All blood flow parameters,blood pressure (BP) and intraocular pressure (IOP) measurements were obtained within a 2-hour period.Univariate regression analyses were used to evaluate the correlation of POBF with MBF, retrobulbar velocity and resistive index (RI) in each group. A multiple linear regression model was used including: POBF, MBF, age and mean arterial pressure (MAP). A second model included: POBF, temporal short posterior ciliary artery (TSPCA) RI, age and MAP.
Results: :
The mean values of POBF, MBF and TSPCA RI ranged from 13.3-18.1 ml/min, 267.4-282.4 au and 0.70-0.76 respectively, and did not vary significantly between the groups. POBF was significantly associated with MBF (r2=0.54; P < 0.001, positive correlation) and TSPCA RI (r2=0.39; P < 0.001, negative correlation) in normal subjects. Results were consistent when corrected for age, IOP and BP parameters. POBF did not correlate with parapapillary blood flow or retrobulbar flow velocities in glaucoma suspects or OAG patients.(Table)
Keywords: blood supply • optic disc • retina