Abstract
Purpose :
To examine the relationship between retrobulbar blood flow parameters and functional progression in open-angle glaucoma (OAG) patients aged <65 and those ≥65 years old
Methods :
112 OAG patients (50 aged <65 years, 62 aged ≥65 years) were assessed for peak systolic velocity (PSV) and end diastolic velocity (EDV) in the ophthalmic (OA) and temporal posterior ciliary arteries (TPCA) as measured by color Doppler imaging at baseline and every six months for five years. 76 patients (25 aged <65 years, 51 aged ≥65 years) were assessed at five-year follow-up. Visual field analysis was performed with Humphrey 24-2 and functional disease progression was defined as two consecutive visits with mean deviation decrease ≥2 and/or Advanced Glaucoma Intervention Study score increase ≥2 compared to baseline. Mixed model ANCOVA was used to test for statistically significant changes from baseline to five-year follow-up. Time to functional progression was analyzed using Cox proportional hazards survival analysis. Interactions were tested to determine if the effects of factors on progression time differed by age status.
Results :
In patients <65 years old, OA EDV decreased from baseline 6.3 (95% CI: 5.5, 7.3) to 4.4 (3.6, 5.3) at five years, mean change -2.8 (-4.5, -1.4; p<0.001). TPCA EDV also decreased from 2.4 (2.2, 2.7) to 1.9 (1.7, 2.1), mean change -0.7 (-1.1, -0.3; p<0.001). However OA PSV did not significantly change from 23.7 (20.8, 27.1) at baseline to 20.9 (17.6, 24.8) at five years, mean change -3.3 (-7.3, 0.3; p=0.072). Similarly in patients >65 years old, OA EDV decreased from 5.5 to 3.8, mean change -2.4, TPCA EDV decreased from 2.4 to 1.8, mean change -0.9, and OA PSV did not significantly change from 23.4 to 20.1, mean change -0.4. Lower OA PSV, lower OA EDV, and higher TPCA EDV were predictive of functional progression in OAG patients aged <65 years after five years only, resulting in a significant difference between age groups (p<0.05).
Conclusions :
In this group of OAG patients, retrobulbar blood flow was more predictive of functional vision loss in glaucoma patients younger than 65 years old, compared to OAG patients 65 and older. Therefore, changes in blood flow may play a larger role in functional disease progression in younger patients compared to those age 65 and older.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.