Effectiveness of Cupulolith Repositioning Maneuver in the Treatment of Lateral Semicircular Canal Cupulolithiasis / 대한이비인후과학회지

ABSTRACT

BACKGROUND AND OBJECTIVES: There is still a controversy surrounding lesion side differentiation and treatment of the lateral canal cupulolithiasis. The purpose of this study is to understand side differentiation, and study the treatment of this disease through analyses of clinical features, electronystagmographic (ENG) results, treatment maneuvers and its effectiveness. MATERIALS AND METHODS: Twenty three patients who showed ageotropic direction-changing horizontal positional nystagmus were included in this study. A supine head turning test was performed to induce positional nystagmus. Clinical findings and typical features of the nystagmus were recorded. Neurologic examinations, ENG tests, and MRI (6 cases) were checked to exclude the possibility of any central lesions. Cupulolith Repositioning Maneuver (CuRM) was applied on the patients and these patients were instructed to keep the healthy side at the lateral decubitus position while sleeping. RESULTS: The nystagmus had a short latency, no fatigability, and persistency in character. In one patient, nystagmus was resolved spontaneously, so we could not decide the lesion side. However, seventeen out of 22 patients showed significant differences between the intensity of each side nystagmus, and all of them showed stronger nystagmus when the head was rotated to the unaffected side. In five patients who showed no significant difference between the intensity of each side nystagmus, two cases showed same results and three cases showed opposite results. Typical nystagmus and spinning sensation in the supine head-turning test had completely subsided after physical therapy. CONCLUSION: In the cupulolithiasis of lateral semicircular canal, ageotropic nystagmus was stronger when the pathological ear was at the uppermost position, and this excitatory nystagmus beat to the lesion side. But, if there was no significant difference between the intensity of each side nystagmus, associated canal paresis, other types of BPPV, past history of acute vestibuloneuritis, and Meniere's disease, etc. might be helpful to localize the lesion side. CuRM and post- treatment lateral decubitus position kept during the night (while sleeping on the day of treatment) were effective in treating the cupulolithiasis of lateral semicircular canal.