Visual Suppression Test Using Post-Rotatory Nystagmus: Clinical Course in Patients with Motion Sickness

Abstract

With the results of VS test (%) we were able to classify patients into three groups as follows: Group I, hyper range of visual suppression, VS (%)= 100−90; Group II, normal range of VS (%)=89−45; Gorup III, reduced or abolished range of VS (%)=less than 44. The results with VS test using post-rotatory nystagmus (PRN) were in Group I 58 cases, in Group II 28 cases and in Group III 1 case, and using caloric nystagmus (CN) the results in Group I were 39 cases, Group II 29 cases, and Group III 1 case. With the correlation of VS test between PRN and CN we were able to classify patients into four types as follows: Type I, hyper range of VS in both PRN and CN; Type II, hyper range of VS in PRN; however, normal range of VS in CN; Type III, normal range of VS in both PRN and CN; Type IV reduced or abolished range of VS in both PRN and CN. It was very interesting in the clinical course of motion sickness that patients under 11 years of age (18 cases) of Type I (31 cases) showed marked improvement to Type III (11 cases) at the time of disappearence of symptoms; however, patients over 12 years of age (13 cases) of Type I remaind stationary Type I (9 cases) at the time of disappearence of symptoms.