Hui Wang1, Qingxiu Yao1, Zhuangzhuang Li1, Dongzhen Yu2, Haibo Shi3. 1. Department of Otolaryngology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital. Shanghai Key Laboratory of Sleep Disordered Breathing, Shanghai, 200233, China. 2. Department of Otolaryngology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital. Shanghai Key Laboratory of Sleep Disordered Breathing, Shanghai, 200233, China. drdzyu@126.com. 3. Department of Otolaryngology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital. Shanghai Key Laboratory of Sleep Disordered Breathing, Shanghai, 200233, China. hbshi@sjtu.edu.cn.
Abstract
OBJECTIVES: Positional nystagmus can be related to various kinds of disorders. The current study aims to compare the direction-changing horizontal positional nystagmus (DCPN) characteristics in horizontal canal canalolithiasis (HC-canalolithiasis), heavy cupula of the horizontal canal (HC-Hcu), and light cupula of the horizontal canal (HC-Lcu), especially the temporal patterns of positional nystagmus in three disorders. METHODS: 52 patients (22 males, 30 females; mean age, 49.6 years) presenting with geotropic or apogeotropic DCPN were enrolled, and they were divided into HC-canalolithiasis, HC-Hcu, or HC-Lcu groups according their nystagmus characteristics. We compared their latency, time constant, peak slow-phase velocity (SPV), time to reach peak SPV intensity (Tpeak), and time to decay to half-peak intensity (T1/2peak). RESULTS: The time to reach peak SPV did not differ significantly between the HC-Hcu (23.1 ± 8.6 s) and HC-Lcu (24.4 ± 9.9 s) groups (p = 0.733), but was significantly longer than that of the HC-canalolithiasis group (5.4 ± 3.5 s; p ≤ 0.001). The peak intensity did not differ among the canalolithiasis (36.4 ± 20.6º/s), HC-Hcu (30.1 ± 23.6º/s), and HC-Lcu (21.4 ± 12.7º/s) groups (p = 0.133). The onset latency also had no statistical difference among three groups (p = 0.200). The nystagmus patterns of HC-Lcu and HC-Hcu groups were similar, including latency, peak SPV intensity, Tpeak, T1/2peak, and SPV in 20 s, 40 s, 60 s, 80 s. CONCLUSIONS: The nystagmus characteristics of HC-Hcu and HC-Lcu are similar, except for the fact that movement was in opposite directions, suggesting that HC-Hcu and HC-Lcu may result from a similar pathophysiological mechanism (cupulopathy) differing from that underlying canalolithiasis.
OBJECTIVES: Positional nystagmus can be related to various kinds of disorders. The current study aims to compare the direction-changing horizontal positional nystagmus (DCPN) characteristics in horizontal canal canalolithiasis (HC-canalolithiasis), heavy cupula of the horizontal canal (HC-Hcu), and light cupula of the horizontal canal (HC-Lcu), especially the temporal patterns of positional nystagmus in three disorders. METHODS: 52 patients (22 males, 30 females; mean age, 49.6 years) presenting with geotropic or apogeotropic DCPN were enrolled, and they were divided into HC-canalolithiasis, HC-Hcu, or HC-Lcu groups according their nystagmus characteristics. We compared their latency, time constant, peak slow-phase velocity (SPV), time to reach peak SPV intensity (Tpeak), and time to decay to half-peak intensity (T1/2peak). RESULTS: The time to reach peak SPV did not differ significantly between the HC-Hcu (23.1 ± 8.6 s) and HC-Lcu (24.4 ± 9.9 s) groups (p = 0.733), but was significantly longer than that of the HC-canalolithiasis group (5.4 ± 3.5 s; p ≤ 0.001). The peak intensity did not differ among the canalolithiasis (36.4 ± 20.6º/s), HC-Hcu (30.1 ± 23.6º/s), and HC-Lcu (21.4 ± 12.7º/s) groups (p = 0.133). The onset latency also had no statistical difference among three groups (p = 0.200). The nystagmus patterns of HC-Lcu and HC-Hcu groups were similar, including latency, peak SPV intensity, Tpeak, T1/2peak, and SPV in 20 s, 40 s, 60 s, 80 s. CONCLUSIONS: The nystagmus characteristics of HC-Hcu and HC-Lcu are similar, except for the fact that movement was in opposite directions, suggesting that HC-Hcu and HC-Lcu may result from a similar pathophysiological mechanism (cupulopathy) differing from that underlying canalolithiasis.
Entities:
Keywords:
Canalolithiasis; Heavy cupula; Horizontal canal; Light cupula
Authors: M von Brevern; A Radtke; F Lezius; M Feldmann; T Ziese; T Lempert; H Neuhauser Journal: J Neurol Neurosurg Psychiatry Date: 2006-11-29 Impact factor: 10.154