Abstract
Purpose:
To evaluate the impact of retinal blood flow on optic nerve head morphology in open-angle glaucoma (OAG) patients with and without diabetes mellitus (DM).
Methods:
66 patients with OAG (14 with DM; 52 without DM) were assessed at baseline and 3 year follow up for retinal capillary blood flow using confocal scanning laser Doppler and ocular structure using Heidelberg retinal tomography and optical coherence tomography. Pearson correlations were calculated to evaluate the associations between measurements at baseline and between the changes in measurements between baseline and 3 years.
Results:
Change from baseline to 3 years in the amount of zero blood flow in the superior retina significantly correlated with the change in maximum cup depth in patients with DM (r=-0.91, p=0.0298), but this change was not significant in those without DM (p=0.8087); and was significantly different between groups (p<0.0000). Change in inferior zero pixel blood flow was significantly correlated with the change in cup to disc (C/D) area ratio (r=-0.92, p=0.0273), and C/D vertical ratio (r=0.9, p=0.0353) in diabetic patients, but not in non-diabetics (p>0.05), with significant differences between groups (p<0.0001). Change in superior mean retinal flow was significantly correlated with change in cup area (r=-0.30, p=0.0498), cup volume (r=-0.36, p=0.0178) and rim volume (r=0.35, p=0.0193) in patients without DM, but not in diabetics (p>0.05), with a significant difference between the 2 groups (p<0.0101). The change in inferior mean flow significantly correlated with the change in cup area (r=0.97, p=0.0029), C/D area ratio (r=0.96, p=0.0070), linear C/D ratio (r=0.93, p=0.0172), rim area (r=-0.97, p=0.0036) and rim volume (r=-0.95, p=0.0084) in diabetics, but not in non-diabetics (p>0.05); with a significant difference between groups (p≤0.0001).
Conclusions:
In this cohort of patients with OAG, changes in retinal capillary blood flow correlated more strongly with changes in optic nerve head morphology in patients with DM than in those without DM. This data suggests that changes in retinal blood flow may play a larger role in optic nerve head morphology in OAG patients with DM.
Keywords: 498 diabetes •
688 retina •
436 blood supply