[Electronystagmographic objective perimetry]

We have recently been referred patients with visual field contraction from simulation or aggravation. For unmasking, we used optokinetic nystagmus, which can also be induced by stimulation of the peripheral retina. At electronystagmography the central portion of the screen was covered from 20 degrees-60 degrees by means of a black disk in front of the projection nystagmus drum. In the centre of the screen a light spot was installed, which blocked the nystagmus. On turning off the light spot, the optokinetic nystagmus was registered when there was no visual contraction at this degree. The examination was successful except for one case with coarse, spontaneous nystagmus in all 18 eyes of 10 patients, in which a visual field contraction from simulation or aggravation was suspected.