National Institute for Health and Medical Research (Inserm), U 954, Thematic group Neurodegenerative Diseases, Neuroplasticity, Cognition, Faculty of Medicine, Vandoeuvre-lès-Nancy, France.
Neuroscience. 2011 Jan 13;172:285-92. doi: 10.1016/j.neuroscience.2010.10.059. Epub 2010 Oct 28.
This longitudinal study aimed to assess the sensorimotor balance strategies before and after vestibular schwannoma (VS) surgery according to the degree of pre-operative vestibular lesion. Thirty-eight VS patients were split in three groups according to caloric vestibular test results before surgery; nine had a symmetrical vestibular response (vestibular normoreflexy), 19 with a decreased response of more than 20% of the affected side (vestibular hyporeflexy) and 10 with an absent caloric response on the side of the affected labyrinth (vestibular areflexy). They underwent pendular rotary vestibular testing (RVT), allowing to evaluate gain and directional preponderance of the vestibulo-ocular reflex, and a sensory organisation test (SOT), evaluating balance control in six conditions (C1 to C6). These tests were performed shortly before, and 8 and 90 days after surgery. Directional preponderance performances of patients with vestibular normoreflexy or hyporeflexy followed a classical time-course with a huge asymmetry just after surgery and a recovery to pre-operative performances at 90 days; patients with vestibular areflexy were relatively stable in time. Variation in SOT performances of patients with vestibular normoreflexy, especially in the more complex C4 to C6, followed a classical time-course with an important postural degradation just after surgery and a recovery to pre-operative performances at 90 days. Patients with vestibular areflexy showed no balance degradation just after surgery and a marked increase in performances at 90 days after surgery, especially in C5 and C6. Performances of patients with vestibular hyporeflexy were intermediate, close to performances of patients with vestibular normoreflexy before surgery and close to performances of patients with vestibular areflexy at 8 and 90 days after surgery. Pre-operative vestibular function alteration triggers an adaptive process, characterized by a restoration of the symmetry of the vestibular nuclei activity and by sensory substitution and new behavioural strategies, allowing the anticipation of unilateral vestibular deafferentation effects.
本纵向研究旨在根据术前前庭病变程度评估前庭神经鞘瘤 (VS) 手术后的感觉运动平衡策略。38 例 VS 患者根据术前冷热前庭试验结果分为三组；9 例存在双侧前庭反应对称（前庭正常反射），19 例患侧反应下降超过 20%（前庭低反射），10 例患侧迷路无冷热反应（前庭反射消失）。他们接受了摆式旋转前庭测试 (RVT)，可评估前庭眼反射的增益和方向优势，以及感觉组织测试 (SOT)，评估六种条件下的平衡控制 (C1 至 C6)。这些测试在手术前、手术后 8 天和 90 天进行。前庭正常反射或低反射患者的方向优势表现遵循经典的时间进程，术后即刻出现巨大的不对称，90 天后恢复术前表现；前庭反射消失的患者随时间相对稳定。前庭正常反射患者的 SOT 表现变化，尤其是在更复杂的 C4 至 C6，也遵循经典的时间进程，术后即刻出现明显的姿势恶化，90 天后恢复术前表现。前庭反射消失的患者术后即刻无平衡恶化，90 天后表现明显改善，尤其是在 C5 和 C6。前庭低反射患者的表现居中，接近术前前庭正常反射患者的表现，接近术后 8 天和 90 天前庭反射消失患者的表现。术前前庭功能改变触发了一种适应性过程，其特征为前庭核活动对称性的恢复以及感觉替代和新的行为策略，从而可以预测单侧前庭去传入的影响。
