Lapenna R, Pellegrino A, Ricci G, Cagini C, Faralli M
Department of Surgical and Biomedical Sciences, Section of Otorhinolaryngology, University of Perugia, Italy.
Department of Surgical and Biomedical Sciences, Section of Ophthalmology, University of Perugia, Italy.
Acta Otorhinolaryngol Ital. 2018 Apr;38(2):138-144. doi: 10.14639/0392-100X-1645.
Conjugated cyclotorsion of the eyes toward the affected side can commonly be observed in vestibular neuritis. The aim of this study was to assess the differences in cyclotorsion between the ipsi- and contralesional eye during selective involvement of the superior branch of the vestibular nerve. We studied binocular cyclotorsion through ocular fundus photographs in 10 patients affected by acute superior vestibular neuritis (SVN). Cyclotorsion was also studied in 20 normal subjects. All SVN patients showed an ipsilesional cycloversion of the eyes. Normal subjects exhibited a constant mild excyclovergence (6.42 ± 2.34°). In SVN patients, contralateral incyclotorsion (8.4 ± 8.14°) was lower and not normally distributed compared to ipsilateral eye excyclotorsion (17.9 ± 4.36°) with no correlation between them. The interocular difference in cyclodeviation could be related to the starting physiological excyclovergence, to different tonic effects on the extraocular muscles of the two eyes and to the different influence of spontaneous nystagmus on cyclodeviation in the two eyes. We recommend referring only to ipsilateral excyclotorsion in the evaluation of utricular function during SVN and its subsequent compensation. Further studies are required to determine the binocular cyclotorsion in the case of other kinds of selective involvement of the vestibular nerve.
在前庭神经炎中通常可观察到双眼向患侧的共轭性眼球旋转。本研究的目的是评估在前庭神经上支选择性受累期间患侧眼与对侧眼之间眼球旋转的差异。我们通过眼底照片研究了10例急性上半规管神经炎（SVN）患者的双眼眼球旋转情况。还对20名正常受试者进行了眼球旋转研究。所有SVN患者均表现出患侧眼的眼球旋转。正常受试者表现出持续的轻度外旋转性散开（6.42±2.34°）。在SVN患者中，与患侧眼的外旋转（17.9±4.36°）相比，对侧眼的内旋转（8.4±8.14°）较低且分布不正常，两者之间无相关性。眼球旋转偏差的眼间差异可能与起始的生理性外旋转性散开、对两眼眼外肌的不同张力作用以及自发性眼球震颤对两眼眼球旋转偏差的不同影响有关。我们建议在评估SVN及其后续代偿过程中的椭圆囊功能时仅参考患侧眼的外旋转。对于前庭神经其他类型的选择性受累情况，还需要进一步研究来确定双眼眼球旋转情况。
