Abstract
Purpose: :
To examine the associations over a two-year period between retinal capillary blood flow and optic nerve structure in patients with open angle glaucoma (OAG).
Methods: :
50 patients with OAG were analyzed for retinal capillary blood flow and optic nerve structure at baseline and after 2 years follow up. Total retinal capillary blood flow was divided into 10, 25, 50, 75 and 90 percentiles of total flow via scanning laser Doppler flowmetry. Associations between the changes in retinal capillary blood flow and optic nerve structure were evaluated using Pearson correlation coefficients.
Results: :
Superior and inferior retinal blood flow were negatively correlated with optic cup depth as measured by HRT3. Specifically, as the superior 25th/ 50th/75th/90th percentile and mean retinal blood flow decreased, the mean optic cup depth increased (r=-0.28, p=0.0487; r=-0.34, p=0.0152; r=-0.38, p=0.0057; r=-0.40, p=0.0035; r=-0.36, p=0.0092). Similarly, as the inferior 10th/25th/ 50th/75th/90th percentile and mean retinal blood flow decreased, the mean optic cup depth increased (r=-0.28, p=0.0450; r=-0.36, p=0.0097; r=-0.38, p=0.0066; r=-0.38, p=0.0054; r=-0.33, p=0.0183; r=-0.37, p=0.0074). Furthermore, as the inferior 10th/25th/ 50th/75th/90th percentile and mean retinal blood flow decreased, the maximum optic cup depth increased (r=-0.30, p=0.0355; r=-0.38, p=0.0057; r=-0.39, p=0.0049; r=-0.41, p=0.0030; r=-0.41, p=0.0027; r=-0.43, p=0.0017).
Conclusions: :
Decreased capillary perfusion in the retina is associated with an increase in optic cup depth in this cohort of patients with OAG. This applies to perfusion in both the superior and inferior aspects of the retina. Thus, decreasing retinal blood flow may increase optic nerve damage as defined by optic cup depth in patients with OAG.
Keywords: optic nerve • imaging/image analysis: non-clinical • blood supply