Quantitative measurement of smooth pursuit using the continuously changing sinusoidal wave in neurological patients

In a previous paper [Ohashi, Watanabe, Kobayashi, Mizukoshi: ORL 47: 49-56] we developed a new sinusoidal wave with 20 continuously changing sinusoidal waves from 0.1 to 2.0 Hz and reported that in normal subjects the limit of smooth pursuit was 1.2 Hz, retinal error velocity (REV) was the most reliable parameter as input of smooth pursuit and amplitude gain was the most reliable parameter as output. In the present paper, we analyzed smooth pursuit system by the same method and discussed the relation between input and output of smooth pursuit in patients with neurological disorders. Our results indicated that the relationship between input and output of the smooth pursuit was particularly abnormal in patients with cerebellar disorders.