Nuffield Laboratory of Ophthalmology, Walton Street, University of Oxford, UK. karl-georg.schmidt@eye.ox.ac.uk
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) A(1c) 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 HbA(1c) were significantly altered in DR-0, DR-1, or DR-2 IDDM patients. CONCLUSION: Choroidal circulation remains unaffected as diabetic retinopathy advances.