Samii M, Rosahl S K, Carvalho G A, Krzizok T
Department of Neurosurgery, Nordstadt Hospital, Hannover, Germany.
J Neurosurg. 1998 Dec;89(6):1020-4. doi: 10.3171/jns.1998.89.6.1020.
Superior oblique myokymia (SOM) is a rare eye movement disorder presenting as uniocular rotatory microtremor due to intermittent contractions of the superior oblique muscle. Medical treatment usually fails to provide long-term benefit for the patient and has considerable side effects. Surgical alternatives including tenotomy or partial tenectomy of the superior oblique tendon often result in incomplete resolution of the visual symptoms. The authors report a patient who experienced immediate cessation of disabling SOM following microvascular decompression of the fourth nerve at the root exit zone. Temporary double vision at downgaze resolved 5 months after surgery. There was no recurrence of oscillopsia during a follow-up of 22 months to date. From this single observation it appears likely that vascular compression of the trochlear nerve could be a significant pathophysiological factor contributing to SOM. In the hands of an experienced surgeon, microvascular decompression at the brainstem exit zone of this nerve may evolve as the method of choice for selected cases of disabling SOM.
上斜肌肌阵挛（SOM）是一种罕见的眼球运动障碍，表现为由于上斜肌间歇性收缩导致的单眼旋转性微震颤。药物治疗通常无法为患者提供长期益处，且有相当多的副作用。包括上斜肌腱切断术或部分切除术在内的手术选择往往不能使视觉症状完全缓解。作者报告了一名患者，在第四神经根部出口区进行微血管减压术后，致残性SOM立即停止。向下注视时的暂时性复视在术后5个月消失。在迄今为止22个月的随访中，未出现视振荡复发。从这一单一观察结果来看，滑车神经的血管压迫可能是导致SOM的一个重要病理生理因素。在经验丰富的外科医生手中，该神经脑干出口区的微血管减压术可能会成为某些致残性SOM病例的首选治疗方法。
