Glaucoma screening during regular optician visits: the feasibility and specificity of screening in real life

Purpose: To determine the feasibility and specificity of glaucoma screening during regular optician visits. Methods: In four optician shops, glaucoma screening was offered to 400 consecutive visitors aged 45 years or above. If the visitor agreed to participate, an intraocular pressure measurement and - in those with a pressure below 25 mmHg - a frequency-doubling perimeter (FDT) C20-1 visual field screening test were performed. Those with an elevated pressure or at least one reproducibly abnormal test location on FDT were referred to our hospital. Results: Three-hundred and fifty-two of 400 consecutive visitors (88%) were screened. Fifteen of the unscreened visitors were not screened because they were already regularly checked by an ophthalmologist related to glaucoma. Forty-two of 352 screened participants (12%) were referred. Of these 42 referrals, seven were diagnosed with glaucoma, 10 were diagnosed with ocular hypertension (OHT), 12 did not have any eye disease, seven had an eye disease other than glaucoma or OHT that was diagnosed previously and six were newly diagnosed with an eye disease other than glaucoma or OHT. The specificity of the screening protocol was 91% (95% confidence interval 88-94%). Conclusions: Glaucoma screening at the optician shop was feasible, but the specificity of the screening protocol was rather low. With more stringent cutoff points (30 mmHg; at least two reproducibly abnormal test locations), the specificity could be improved to 96% (94-98%), apparently without a significant loss of sensitivity. This suggests that screening during regular optician visits might be a viable approach.