HEMANGIOBLASTOMA AND OCULOMOTOR PATHOLOGY

We examined voluntary eye movements of 20 ophtalmologically screened p atients (mean age of 51 years) with operated hemangioblastoma (HAB) in the cerebellum. Constant and pseudo-random saccades and pseudo-random smooth pursuit eye movement (PRPEM) test (with 4 frequency combinatio ns) were evaluated. As controls 38 healthy subjects were examined. In the logistic regression analysis latency and accuracy of constant sacc ades were the best predictors for operated HAB with correct overall cl assification rate of 79.3%. Accuracy was worse and latency longer in o perated HAB group than in control group. In pseudo-random saccades cor rect classification between the groups was achieved in 82.8% of all ca ses with latency and accuracy as predictors. In PRPEM lest the best fr equency combinations in differentiating operated HAB patients from con trols were 0.25 and 0.425 Hz for gain, and 0.3 and 0.7 Hz for phase an d gain, the correct overall classification rate being 73.3% in both ca ses. The characteristic changes in voluntary eye movements after remov al of cerebellar hemangioblastoma seem to be insufficient timing of in itiating the eye movement.