R. Stodtmeister

Autoregulation of ocular blood flow during changes in intraocular pressure. Preliminary results

Visual evoked potentials were recorded in six normal subjects and in three patients with primary open-angle glaucoma, while intraocular pressure was artificially elevated in stepwise increases. The resulting perfusion-pressure amplitude curves in our controls showed a kink, which can be interpreted as a sign of vascular autoregulation. No kink was observed in the curves of our glaucoma patients, which we interpret as indicating a lack of vascular autoregulation in primary open-angle glaucoma.

Effect of Timolol on Optic Nerve Head Autoregulation

Healthy subjects show, in a special pressure compliance test of the optic nerve head, signs of autoregulation of optic nerve head circulation. In this test visual evoked response (VER) amplitudes were recorded during stepwise increased intraocular pressures. In the resulting VER amplitude/pressure curves glaucoma patients did not show the sign of autoregulation of optic nerve head circulation which is seen in healthy subjects. It is known that topically applied timolol maleate may affect optic nerve head circulation. Therefore the pressure compliance test was performed in 20 healthy eyes before and after 3 days of topically applied timolol maleate 0.5%. The aim of the study was to test the effect of topically applied timolol on optic nerve head autoregulation. In addition we determined the ocular perfusion pressures, heart rate and mean arterial blood pressure. While the ocular perfusion pressures show a slight, but statistically not significant, decrease under timolol, the systemic parameters and the autoregulation behavior did not change.

FLICKER FUSION FREQUENCY AND ORGANIC SYNDROME IN ALCOHOLICS

Flicker fusion frequencies of 48 healthy controls and of 35 alcoholics were measured to detect possible associations between flicker fusion and signs of nonspecific brain damage, the aim of the study. FFF was statistically significantly lower in patients addicted to alcohol than in healthy subjects. Lower flicker fusion frequencies were associated with the severeness of organic psychosis as rated psychopathologically. The hypothesis that addiction to alcohol is a sign of diffuse, nonspecific, organic brain damage was discussed.

The 'flicker test' according to Aulhorn in the diagnosis of acute optic neuritis.

The flicker test, introduced by Aulhorn is a new simple method to detect acute optic neuritis. We examined 24 patients suffering from acute optic neuritis. 23 patients showed a pathological result. In 179 subjects (patients with other ophthalmological diseases and healthy persons) the flicker test always showed normal results. After restitution of acute optic neuritis the results of the flicker test return to normal while the visual evoked responses remain pathological in many cases. Thus the flicker test can be an efficient tool in the diagnosis and differential diagnosis of acute optic neuritis.