Magnusson Måns, Kahlon Babar, Karlberg Mikael, Lindberg Sven, Siesjö Peter, Tjernström Fredrik
Department of Otorhinolaryngology, Lund University Hospital, Lund University, 221 85 Lund, Sweden. n.
Ann N Y Acad Sci. 2009 May;1164:257-62. doi: 10.1111/j.1749-6632.2009.03778.x.
A sudden unilateral loss or impairment of vestibular function causes vertigo, dizziness, and impaired postural function. In most occasions, everyday activities supported or not by vestibular rehabilitation programs will promote a compensation and the symptoms subside. As the compensatory process requires sensory input, matching performed motor activity, both motor learning of exercises and matching to sensory input are required. If there is a simultaneous cerebellar lesion caused by the tumor or the surgery of the posterior cranial fossa, there may be a risk of a combined vestibulocerebellar lesion, with reduced compensatory abilities and with prolonged or sometimes permanent disability. On the other hand, a slow gradual loss of unilateral function occurring as the subject continues well-learned everyday activities may go without any prominent symptoms. A pretreatment plan was therefore implemented before planned vestibular lesions, that is, "PREHAB." This was first done in subjects undergoing gentamicin treatment for morbus Ménière. Subjects would perform vestibular exercises for 14 days before the first gentamicin installation, and then continue doing so until free of symptoms. Most subjects would only experience slight dizziness while losing vestibular function. The approach--which is reported here--was then expanded to patients with pontine-angle tumors requiring surgery, but with remaining vestibular function to ease postoperative symptoms and reduce risk of combined cerebellovestibular lesions. Twelve patients were treated with PREHAB and had gentamicin installations transtympanically. In all cases there was a caloric loss, loss of VOR in head impulse tests, and impaired subjective vertical and horizontal. Spontaneous, positional nystagmus, subjective symptoms, and postural function were normalized before surgery and postoperative recovery was swift. Pretreatment training with vestibular exercises continued during the successive loss of vestibular function during gentamicin treatment, and pre-op gentamicin ablation of vestibular function offers a possibility to reduce malaise and speed up recovery.
前庭功能突然单侧丧失或受损会导致眩晕、头晕和姿势功能受损。在大多数情况下，无论是否有前庭康复计划支持的日常活动都会促进代偿，症状也会消退。由于代偿过程需要感觉输入，因此需要将所进行的运动活动与感觉输入相匹配，既需要运动学习练习，也需要与感觉输入相匹配。如果同时存在由后颅窝肿瘤或手术引起的小脑病变，则可能存在合并前庭小脑病变的风险，代偿能力降低，残疾时间延长，有时甚至是永久性残疾。另一方面，在受试者持续进行熟练的日常活动时，单侧功能缓慢逐渐丧失可能不会出现任何明显症状。因此，在计划进行前庭病变之前实施了一项预处理计划，即“PREHAB”。这首先在接受庆大霉素治疗梅尼埃病的受试者中进行。受试者在首次注射庆大霉素前14天进行前庭锻炼，然后继续进行，直到症状消失。大多数受试者在丧失前庭功能时只会感到轻微头晕。这里报道的方法随后扩展到需要手术但仍保留前庭功能的桥小脑角肿瘤患者，以减轻术后症状并降低合并小脑前庭病变的风险。12例患者接受了PREHAB治疗，并经鼓膜注射庆大霉素。所有病例均存在冷热试验减退、摇头试验中视眼动反射消失以及主观垂直和水平方向受损。手术前自发性、位置性眼球震颤、主观症状和姿势功能均恢复正常，术后恢复迅速。在前庭功能在庆大霉素治疗期间逐渐丧失的过程中，继续进行前庭锻炼的预处理训练，术前庆大霉素消除前庭功能为减轻不适和加速恢复提供了一种可能性。
