Examination methods for glaucoma prevalence surveys

Abstract

Objective: To perform a pilot evaluation of new examination methods for the detection of glaucoma and other causes of visual impairment in rural East Africa.

Design: Testing was performed by local eye nurses after a brief training course. Two novel tests of visual function were used, a scotopic sensitivity test and a visual field test performed on a laptop computer. The optic disc was examined with direct ophthalmoscopy after pupillary dilation and compared with standard photographs on a laminated card. Intraocular pressure was measured with a hand-held, electronic tonometer.

Setting: Rural Tanzania.

Participants: One hundred twenty adult villagers.

Results: The visual function tests could be performed on more than 90% of subjects, and the results were correlated with the size of the optic disc cup, an objective measure of glaucoma injury.

Conclusions: This survey shows the practicality of instrument-based testing of visual function under field conditions.