PSEUDO RANDOM SMOOTH-PURSUIT TEST IN PATIENTS WITH ACOUSTIC NEUROMA

We examined the pseudo random smooth pursuit test in patients with cer ebellopontine angle (CPA) tumors. Four different frequency combination s of sinusoids 0.15-0.35 Hz, 0.25-0.425 Hz, 0.3-0.7 Hz and 0.45-0.7 Hz were tested. Gain was calculated by comparing the smooth pursuit ampl itude with stimulus after the supporting saccades had been removed. Ph ase was calculated by comparing maximum excursion of the eyes and stim ulus. Gain was in the patients lower than in the controls in different frequency combinations, and the difference was statistically signific ant/highly significant in different frequency combinations. In the pha se shift the differences were highly significant in the two higher fre quency combinations and significant in the second frequency combinatio n (0.25-0.425 Hz), while in the first frequency combination (0.15-0.35 Hz) the difference was not significant. The gain method was a somewha t better analyzing method than the phase shift method.