Researchers recently created a dark adaptation questionnaire—the DA Survey—that could assess severity of binocular visual field loss in patients with primary open-angle glaucoma (POAG). Their study found that such individuals commonly encountered problems with dark adaptation and vision under low luminance. They also found that an increasing DA Survey score correlated with binocular visual field loss among patients with mild, moderate and advanced stages of POAG. 

The study had 85 POAG patients and 127 control patients complete the questionnaire, which was given to patients during a routine clinical evaluation in a hospital-based eye clinic. Researchers abstracted retrospective data related to ocular health and glaucoma severity from medical records.

They used a model to differentiate patients with POAG from controls that included average and inter-eye difference in cup-to-disc ratio, family history of glaucoma and DA Survey score. The model achieved accuracy, sensitivity and specificity values of 96.7%, 92.9% and 99.2%, respectively.

The study concludes that problems with dark adaptation and vision under low luminance are areas of visual disability not routinely assessed in glaucoma care. A questionnaire addressing such functions could serve as a proxy for functional impairment in glaucoma. Researchers believe that, when paired with risk factors such as structural features of the optic nerve and family history, the DA Survey could be suitable to help screen POAG patients.