Outcome of Canalith Repositioning Procedure in Patients with Persistent and Transient Geotropic Direction-Changing Positional Nystagmus: Short-term Follow-up Evaluation / 대한평형의학회지

ABSTRACT

OBJECTIVES: Patients, who showed persistent geotropic-direction changing positional nystagmus (p-DCPN) tend to have different clinical manifestations from those who showed transient geotropic DCPN (t-DCPN). We investigated the clinical characteristics between p-DCPN and t-DCPN patients, and its recovery rate after canalith repositioning procedure (CRP). METHODS: Based on the duration of nystagmus, 117 geotropic DCPN patients were classified to 2 groups, p-DCPN and t-DCPN. Barbeque maneuver had been introduced towards the opposite direction of null plane for the p-DCPN patients, and to the opposite direction of stronger nystagmus for the t-DCPN patients. RESULTS: Seventy-four patients showed t-DCPN and 43 patients were classified to the p-DCPN cases. No p-DCPN patient showed prompt improvement after the 1st canalolith reposition therapy. Among the t-DCPN patients, 18 canal switch cases were found , but, there was no canal switch cases found among the p-DCPN The CRP has showed less effective for the p-DCPN patients than the t-DCPN patients (after the 1st CRP, 37 in 74 improved, p < 0.001). CONCLUSIONS: Due to its distinguishing clinical manifestation, p-DCPN may have different pathogenesis and clinical mechanisms from t-DCPN. And for the p-DCPN patients, the CRP seems not an efficient treatment compared to the t-DCPN patients. Further study with larger number of enrolled subjects is necessary.