Abstract
Purpose :
To examine retrobulbar blood flow parameters and functional and structural progression in patients with open-angle glaucoma (OAG) over a 5-year period
Methods :
76 patients (Mean age 70 ± 10.9 years; 31 male, 45 female) were assessed every 6 months for a 5-year period for retrobulbar blood flow in the ophthalmic (OA), central retinal (CRA), nasal (NPCA) and temporal (TPCA) posterior ciliary arteries as measured by color Doppler imaging at baseline and functional disease progression was monitored with Humphrey visual field (24-2 Swedish Interactive Threshold Algorithm) defined as 2 consecutive visits with mean deviation decrease ≥2 and/or Advanced Glaucoma Intervention Study score increase ≥2 compared to baseline. Structural progression was monitored with optical coherence tomography and Heidelberg retinal tomography and defined as two consecutive visits with retinal nerve fiber layer thickness decrease ≥8% and/or horizontal or vertical cup/disk ratio increase ≥0.2 compared to baseline. Mixed-model ANCOVA was used to test for significant change from baseline to 5-year follow-up. Times to functional and structural progression were analyzed using Cox proportional hazards models.
Results :
OA peak systolic velocity (PSV) was 23.0 (95% CI; 20.9, 25.4) at baseline, 21.8 (19.4, 24.4) at 5 years, change of -1.3 (-3.5, 0.7; p= 0.21), OA end diastolic velocity (EDV) significantly decreased from 5.6 (5.1, 6.2) at baseline to 3.9 (3.5, 4.4) at 5 years, change of -2.4 (-3.3, -1.6; p<0.0001). CRA PSV and EDV significantly decreased with changes of -0.6 (-1.1, -0.1; p=0.0126) and -0.8 (-1.1, -0.5; p<0.0001), respectively. NPCA and TPCA EDV significantly decreased with changes of -0.7 (-0.9, -0.4; p<0.0001) and -0.7 (-1.0, -0.5; p<0.0001), respectively, while neither NPCA nor TPCA PSV changed significantly. Resistivity indices (RI) in all retrobulbar vessels significantly increased over 5-years (p<0.0001). Lower OA PSV and OA EDV were associated with shorter time to functional and structural progression (OA PSV: p= 0.0162; OA EDV: p= 0.0065).
Conclusions :
Lower OA blood flow velocities were predictive of both functional and structural glaucomatous progression after 5 years.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.