Managing 'suspicious glaucomatous discs' identified during digital-photography-based diabetic retinopathy screening

An audit to demonstrate the outcome of patients identified with suspicious glaucomatous discs within a digital-photography-based diabetic retinopathy screening programme.

Primary care based digital photographic screening was performed utilising mydriasis and two-field digital photography for all patients with diabetes. Patients identified with discs suspicious of glaucomatous optic neuropathy (GON) were initially referred to an accredited community-based optometrist for further assessment. Some patients were then referred to secondary care where appropriate.

From 1st April 2002 to 31st March 2003 a total of 3868 patients were screened for diabetic retinopathy. This audit revealed that 55 subjects were identified by retinal screeners as having discs suspicious of glaucoma. A total of 29 were already under glaucoma clinic review. A total of 23/26 remaining were referred for an assessment by an accredited optometrist. Of these 13 were normal, 6 were referred to secondary care and 4 failed to attend. The three remaining were referred directly to secondary care.

All nine referrals to secondary care were deemed appropriate by a glaucoma specialist. This suggests that the system described does not lead to over-referral of suspicious discs - although the issue of how many glaucomatous discs are missed during screening (false negatives) will only be answered in the longer term.