Postural modifications of the oscillatory potentials of the electroretinogram in primary open-angle glaucoma.

The postural variations in the retinal microcirculation in glaucomatous patients were studied by evaluation of the oscillatory potentials (OPs) of the ERG. The OPs in scotopic adaptation were examined in subjects with primary open-angle glaucoma and in an age- and sex-matched normal control group in different body positions (seated, supine, anti-Trendelenburg, Trendelenburg). In the seated position, the difference of mean OP amplitude between the control group and the glaucomatous patients was highly significant (p < 0.001). In the normal subjects the OP amplitude in the Trendelenburg position was statistically lower with respect to the values obtained in all other positions (p < 0.05). In the glaucomatous patient group, the OP amplitude in the anti-Trendelenburg position was increased as compared to the other positions (p < 0.05). The study showed a reduction in amplitude of OPs in glaucomatous patients and their different behaviour in both groups with changes in body position.