Baseline retrobulbar blood flow velocities correlate more strongly with changes in retinal capillary density over 4 years in open angle glaucoma patients with diabetes mellitus

Abstract

Purpose : To examine the relationship between baseline retrobulbar blood flow velocities and longitudinal changes in capillary blood flow in open angle glaucoma (OAG) patients with and without diabetes mellitus (DM)

Methods : 78 patients with OAG (16 with DM, 62 without DM) were assessed for peak systolic (PSV) and end diastolic (EDV) velocities in the nasal and temporal posterior ciliary arteries (NPCA, TPCA) by color Doppler imaging and for capillary blood flow by Heidelberg retinal flowmetry in superior and inferior temporal retinal quadrants at baseline and every 6 months for a 4-year period. Pearson correlations were used to test for associations between measurements, with p<0.05 considered statistically significant.

Results : In OAG patients with DM, baseline NPCA and TPCA EDV were 2.42 (95% CI: 2.11, 2.79) and 2.32 (2.02, 2.67) in patients with DM, and 2.41 (2.23, 2.60) and 2.45 (2.27, 2.65) in patients without DM. In OAG patients with DM, baseline NPCA and TPCA EDV were positively and significantly correlated with changes in inferior retinal capillary density (% zero pixels) (NPCA EDV: r=0.63, p=0.0069; TPCA EDV: r=0.65, p=0.0052), leading to a significant difference compared to patients without DM (NPCA EDV: p=0.0344; TPCA EDV: p=0.0121). There were no significant findings for PSV or superior temporal quadrants of blood flow in the retina for either group.

Conclusions : In OAG patients with DM, baseline retrobulbar blood flow exhibited a significantly stronger relationship to changes in retinal capillary density after 4 years compared to non-diabetic glaucoma patients. This data suggests that the presence of DM may affect ocular blood vessels over time in OAG patients.

This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.