Can pulsatile ocular blood flow distinguish between patients with and without diabetic retinopathy?

Purpose: Our aim was to determine if pulsatile ocular blood flow (POBF) measurements could distinguish between type 2 diabetes mellitus (DM) subjects with and without diabetic retinopathy (DR).
Methods: Ninety-eight DM subjects were recruited. POBF was measured using an Ocular Blood Flow tonometer and retinopathy was assessed using retinal digital photography. The duration of diabetes, blood pressure, glycosylated haemoglobin and plasma glucose level were also recorded.
Results: Seventy-two subjects had no DR and 26 subjects exhibited mild to moderate non-proliferative DR. POBF was higher in those subjects with non-proliferative DR but did not reach significance. Those subjects receiving insulin treatment had a significantly longer duration of DM, higher HbA1c and plasma glucose levels and greater incidence of non-proliferative DR compared to subjects receiving oral hypoglycaemic agents, who in turn demonstrated higher levels of these parameters than those who were controlled by diet alone (ANOVA p < 0.05 in all cases). POBF was found to increase with level of management but not significantly so.
Conclusions: A single measurement of POBF does not distinguish between subjects with and without mild/moderate non-proliferative DR.