卒中后打哈欠致肱肌运动倒错的临床及影像学特点分析

Clinical and radiological characteristics of hemiplegic arm raising related to yawning in stroke patient

目的探讨卒中后打哈欠致肱肌运动倒错(PBO)的临床、影像学特点及可能机制。方法回顾性分析解放军总医院海南分院神经内科收治的4例PBO患者,并结合文献复习,总结PBO的临床和影像学特点及可能的发病机制。结果本组4例患者均因脑卒中出现肢体瘫痪,瘫痪侧上肢不能自主抬起,但患者在恢复过程中、打哈欠时却出现了瘫痪侧上肢的抬起。结合本组4例患者和复习的文献,本文分析的22例患者中男19例,女3例,发病年龄59.1±11.0岁。原发病为脑梗死20例,脑出血2例。影像学上,17例病变位于大脑中动脉供血区域,另有4例位于脑桥,1例位于延髓。PBO出现在卒中后4h^4个月不等(14.57±31.66d),消失时间为1周~3年(6.70±11.66个月)。结合本组病例及文献复习,考虑PBO可能的机制为:哈欠控制中心位于下丘脑室旁核,室旁核催产素能神经元发出的纤维投射至脑干和脊髓,作用于脑干颅神经核团和脊髓前角细胞,引发哈欠和支配肌肉的收缩。锥体束未受损时,其对脊髓前角细胞的支配作用占主导,PBO被抑制;锥体束受损后,这种支配作用减弱或消失,打哈欠时伴随着的前角细胞兴奋导致了肱肌运动倒错。结论 PBO可能是一种较为少见的脑卒中后异常运动现象,这一现象的出现提示锥体束受损,随着锥体束功能的恢复,PBO逐渐消失。

Objective To investigate the clinical and radiological characteristics of parakinesia brachialis oscitans（PBD） related to yawning in stroke patient and its mechanism. Methods We reported 4 patients with involuntary raising of the paralyzed limbs when yawning in neurological unit of Hainan Branch of Chinese PLA General Hospital, and analyzed their clinical characteristics together with published cases in literatures. Results In this group of stroke patients, when they yawned, their paralyzed upper limb could lift upward involuntarily. Totally 22 patients with ischemic（n=20） and hemorrhagic（n=2） stroke were enrolled. Brain imaging showed infarcts in the middle cerebral artery（MCA） in 17 patients and in the brain stem in 5 patients. This phenomenon occurred 4 hours to 4 months（14.57±31.66 d） after stroke onset, and lasted from 1 week to 3 years（6.70±11.66 months）. Corticobulbar tract and pyramidal tract were both damaged in these 22 patients. The mechanism might be that after corticobulbar tract and pyramidal tract damaged, their dominant role in the cranial nerve nuclei of the brainstem and the anterior horn cells of the spinal cord disappeared, and the projection of oxytocinergic neurons from paraventricular nucleus functions, thus causing yawning and muscle contraction. Conclusion PBO may be a rare phenomenon of abnormal movement after stroke. This phenomenon indicates damaging of pyramidal tract, and PBO disappears gradually with the recovery of pyramidal tract function.