[Readaptation time after photo-stress in normal subjects and glaucoma patients].

PURPOSE

A photo-stress test was conducted at the subjective contrast threshold to evaluate whether psychophysical differences could be detected between chronic open-angle glaucoma patients and normal subjects.

METHODS

The prospective, comparative, clinical observational study included 20 patients (29 eyes) with chronic open-angle glaucoma and 20 control subjects (29 eyes). The study groups did not vary significantly in age and refractive error, but visual acuity showed a difference of 0.16. All participants underwent photo-stress using the Kontrastometer BA4.

RESULTS

In the glaucoma group compared with the control group, the mean contrast threshold was significantly higher and the readaptation time significantly longer. The latter correlated significantly with the papillo-morphological glaucoma stage.

CONCLUSIONS

In patients with chronic open-angle glaucoma, the foveal recovery time after a photo-stress test is significantly prolonged compared with normal subjects. It may suggest involvement of the fovea in glaucoma even if the visual acuity is 20/20.