Steddin S, Ing D, Brandt T
Department of Neurology, University of Munich, Klinikum Grosshadern, Germany.
Ann Neurol. 1996 Dec;40(6):918-22. doi: 10.1002/ana.410400615.
We report on 2 patients with typical features of horizontal canal benign paroxysmal positioning vertigo (h-BPPV). A vigorous head positioning in these patients from supine to a bending-over, head-on-the-knees position reversed the direction of nystagmus from geotropic initially to ageotropic when rolling the head from side to side while supine. We explain this by a conversion of canalolithiasis into cupulolithiasis and conclude that (1) canalolithiasis and cupulolithiasis may sequentially occur in the same semicircular canal with subsequent positioning maneuvers and (2) positional nystagmus beating toward the uppermost ear is not a pathognomonic sign of central vestibular disturbance but can indicate occasional cupulolithiasis.
我们报告了2例具有水平半规管良性阵发性位置性眩晕（h-BPPV）典型特征的患者。当这些患者从仰卧位剧烈头部定位到弯腰、头垂在膝盖的位置时，在仰卧位时从一侧向另一侧转动头部，眼震方向最初从向地性转变为背地性。我们将此解释为管结石症转变为嵴顶结石症，并得出结论：（1）管结石症和嵴顶结石症可能在同一个半规管中随着后续的定位操作依次发生；（2）向最高侧耳朵的位置性眼震跳动并非中枢性前庭障碍的特征性体征，但可能提示偶尔出现的嵴顶结石症。
