BACKGROUND The influence of diabetes mellitus on ocular pulse amplitude (OPA), an indirect measure of choroidal perfusion, is unclear. METHODS OPA, using the Langham ocular blood flow (OBF) system, applanation intraocular pressure (IOP), systemic blood pressure (BP), heart rate, and haemoglobin (Hb) A1c were measured in patients with insulin dependent diabetes mellitus (IDDM) with no (DR-0, n = 22) non-proliferative (DR-1, n = 24), and proliferative (DR-2, n = 18) diabetic retinopathy. RESULTS Neither local (OPA, IOP) nor systemic perfusion parameters (BPs, HR) nor HbA1c were significantly altered in DR-0, DR-1, or DR-2 IDDM patients. CONCLUSION Choroidal circulation remains unaffected as diabetic retinopathy advances.
