Harada K, Oda M, Yamamoto M, Nomura T, Ohbayashi S, Kitsuda C
Department of Otolaryngology, Toho University School of Medicine, Tokyo, Japan.
Acta Otolaryngol Suppl. 1993;503:61-3. doi: 10.3109/00016489309128074.
We observed 9 cases of BPPV developed after vestibular neuronitis. The interval between the onset of BPPV and vestibular neuronitis ranged from 2 weeks to 20 years. All cases were examined for critical head position which provoked vertigo, non-gaze nystagmus, positional and positioning nystagmus and caloric nystagmus. No characteristic signs and symptoms could be observed. The function of the posterior canal is thought to be necessary to provoke positional vertigo. Thus in BPPV after vestibular neuronitis the function of the posterior canal would presumably have been preserved to some degree. The first possibility is that the function of the posterior canal was not impaired in spite of the damage of the lateral canal. The fact that each canal differs in involvement in vestibular neuronitis may be explained by the difference in the blood supply or the innervation between lateral and posterior canals. If only the artery or nerve which is related to the lateral canal is damaged and the artery or nerve to the posterior canal is not involved, then the function of the posterior canal is preserved. So BPPV may occur soon after the disappearance of severe vertigo. The second possibility is that if the posterior canal had been damaged together with the lateral canal and the functions are recovering, BPPV may occur some time after the onset of vestibular neuronitis. The locus of vestibular neuronitis is in the peripheral vestibular system and the extent and degree of the lesion vary, which may explain why there can be time difference of the recovery between the two canals.
我们观察到9例前庭神经炎后发生的良性阵发性位置性眩晕（BPPV）。BPPV发病与前庭神经炎之间的间隔时间为2周至20年。所有病例均接受了诱发眩晕的关键头位、非凝视性眼震、位置性和定位性眼震以及冷热试验眼震检查。未观察到特征性体征和症状。后半规管功能被认为是诱发位置性眩晕所必需的。因此，在前庭神经炎后的BPPV中，后半规管功能可能在一定程度上得以保留。第一种可能性是，尽管外半规管受损，但后半规管功能未受损害。外半规管和后半规管在前庭神经炎中的受累情况不同，这一事实可能由它们之间血供或神经支配的差异来解释。如果仅与外半规管相关的动脉或神经受损，而后半规管的动脉或神经未受累，那么后半规管功能得以保留。所以BPPV可能在严重眩晕消失后不久就会发生。第二种可能性是，如果后半规管与外半规管一起受损且功能正在恢复，BPPV可能在前庭神经炎发作后的一段时间出现。前庭神经炎的病灶位于外周前庭系统，病变的范围和程度各不相同，这可能解释了为什么两个半规管的恢复会存在时间差异。
