The detection of diabetic retinopathy by Australian optometrists

Diabetes mellitus is a systemic disease affecting approximately 750,000 Australians of whom more than 70,000 are Queenslanders. It can have serious ocular consequences and patients with diabetes require regular eye examinations to determine the degree of ocular involvement and the stage of retinopathy, if present. It is important that optometrists detect diabetic retinal changes and refer appropriately. We sought to determine the proficiency of optometrists at detecting retinal changes caused by diabetes.

The study comprised four parts: 1. Nineteen randomly recruited Australian optometrists practising in Queensland completed a questionnaire on their experiences seeing patients with diabetes. 2. They examined the ocular fundi of 10 patients. 3. They viewed retinal slides of 12 additional cases. 4. They attended a follow-up seminar on diabetes and the cases. They were informed that the patients did not necessarily have diabetes and instructed not to discuss the condition with the patient or their colleagues. The optometrists were allowed seven minutes per station to examine the patient or the slides and write down their responses before moving to the next station.

When the slides and patients were considered together, cases where diabetic retinopathy was present were correctly identified by 94.0 per cent of the optometrists and cases where retinopathy was not present were correctly identified by 93.6 per cent of the optometrists. When all assessments were considered together, the correct detection/differential diagnosis rate was 88.3 per cent. Sub-classification of diabetic retinopathy severity agreed with that of the reference examiners in 58.3 per cent of assessments and there was agreement on management in 79.4 per cent of cases. Of the 22 assessments undertaken by each optometrist, there were, on average, 2.5 errors.

Randomly selected Australian optometrists are able to detect and grade diabetic retinal changes solely by retinal examination and refer the patients requiring specialist care.