面神经侧方扩散反应在鉴别不同病因面肌痉挛和脑干及其周围肿瘤中的作用

The role of lateral spread response in differentiation of hemifacial spasm with various reasons and tumors in the brainstem and surrounding areas

目的探讨面神经侧方扩散反应(LSR)在鉴别Bell麻痹后遗症、颅内血管压迫面神经导致的面肌痉挛,以及脑干及其周围肿瘤中的作用。方法回顾性纳入2010年1月至2017年12月于贵州省人民医院神经电生理科行LSR检测的患者128例。根据手术证实、头颅MRI及病史将患者分为Bell麻痹后遗症致面肌痉挛组(简称Bell麻痹组,37例)、颅内血管压迫面神经致面肌痉挛组(简称血管压迫组,69例)、脑干及其周围肿瘤组(22例;5例有轻度面肌痉挛)。所有患者均行面肌肌电图、双侧面神经传导速度及双侧LSR检测。结果128例患者中,5例Bell麻痹组患者检测到面神经运动传导速度减慢,其中3例可检出少量失神经电位,其余患者面神经运动传导速度、肌电图均未见异常。37例Bell麻痹组和69例血管压迫组患者痉挛侧均检出LSR,阳性率均为100.0%;22例脑干及其周围肿瘤组患者中,10例(45.4%)在病灶同侧检出LSR(包括5例面肌痉挛患者),其中3例两侧均记录到LSRoBell麻痹组、血管压迫组、脑干及其周围肿瘤组LSR波潜伏期分别为(6.4±2.3)ms、(10.6±3.7)ms及(16.4±5.1)ms,差异有统计学意义(P<0.01)。结论不同病因导致的面肌痉挛患者均可检测到LSR,但LSR波潜伏期存在差异;部分没有面肌痉挛临床表现的脑干及其周围肿瘤患者也可检测到LSR.

Objective To investigate the role of lateral spread response ( LSR) in differentiation of hemifacial spasm caused by Bells palsy, compression of the nerve by blood vessels, tumors in the brainstem or its surrounding areas. Methods We retrospectively analyzed 128 patients who had LSR examination at Neuroelectrophysiological Center of Guizhou Provincial People Is Hospital from January 2010 to December 2017. The patients were divided into group with hemifacial spasm caused by Bells palsy ( Bells palsy group,= 37 ), group with hemifacial spasm due to intracranial blood vessel compression ( vascular compression group, n =69) and group with tumors in the brainstem or its surrounding areas ( n = 22, mild facial spasm in 5 cases) according to surgical confirmation, brain MRI findings and case history. Electromyography, bilateral nerve conduction velocity and LSR examination were performed in all patients. Results Decreased conduction velocity of facial nerve was observed in 5 cases in Bell's palsy group. A little denervation potential was seen in 3 cases in this group. No abnormalities were observed in the all examined muscles of the other patients. LSR was induced on the affected side in 37 cases with Bell s palsy and 69 cases with vascular compression. The positive rate was 100. 0%. LSR waves were induced on ipsilateral side of the lesion in 10 cases (45.4%, including 5 facial spasm patients) and on both sides in 3 cases among 22 cases in group with tumors in the brainstem and its surrounding areas. The LSR latent periods were 6. 4 ± 2. 3 ms, 10. 6 ± 3. 7 ms and 16. 4 ±5. 1 ms in Bells palsy group, vascular compression group and group with tumors in the brainstem and its surrounding areas, respectively(P <0. 01 ). Conclusions LSR could be induced in patients with hemifacial spasm by various causes, which could be present in patients with tumors in the brainstem and its surrounding areas having no clinical manifestations of facial spasm. LSR test might help distinguish the etiology of hemifacial spasm and suggest that there may be tumors in the brainstem and its surrounding areas.