The mainstay of the ophthalmic assessment of patients with type 1 or type 2 diabetes is a comprehensive eye examination. Routine diabetic eye reviews are suggested every 12 months or more frequently if there is any evidence of diabetic retinopathy, macular oedema or high risk of diabetic changes.
A thorough diabetic eye examination involves the following
• Comprehensive history including diabetic medication, RBG levels and HbA1c, if known.
• Visual acuity and refraction if change in the acuity or if new spectacles are required.
• Assessment of the anterior eye including anterior chamber angles to determine suitability for pupil dilation.
• Measurement of intraocular pressure.
• Dilation with 0.5% tropicamide and 2.5% phenylephrine if the dilation is poor or has been poor in the past.
• Evaluation of posterior pole using non-contact fundus lens (90 D, superfield, 78 D or similar) with particular emphasis on macular and disc with regard to macular oedema and new vessels on the disc.
• Assessment of peripheral retina with BIO (20 D or 2.2 or similar) to monitor any diabetic retinal changes in the entire ocular fundus.
• Macular OCT to help detect macular oedema and photo of retinal posterior pole.
• Appropriate review based on findings and the current NHMRC guidelines for diabetic retinopathy which can be viewed at: www.nhmrc.gov.au > Guidelines and Publications > Search. The grading system for diabetic retinopathy is listed in Table 1 with the review recommendations in Table 2.
• Advice to the patient about blood glucose control and the importance with regard to long-term diabetic changes.
• Schedule recall to be sent to patient at the appropriate interval.
• Written report to GP and endocrinologist.
Table 1. Classification of diabetic retinopathy into retinopathy stages (Wisconsin level) and predictive value of retinal lesions (adapted from Focal Points)
Table 2. Summary of diabetic retinopathy management recommendations (adapted from the AAO, ICO, ETDRS and NHMRC guidelines)