Observation of Effects of Different Surgical Treatments on Unilateral Masticatory Muscle Spasm

Treatment of hemimasticatory spasm secondary to parry-romberg syndrome via partial resection of the trigeminal nerve motor branch under intraoperative neurophysiological monitoring: A case report and literature review

“…In uncomplicated HMS, some research has found electrophysiologically similar potentials to the facial nerve of hemifacial spasm ( 12 – 18 , 20 ). In recent years, an increasing number of experts concur with the neurovascular conflict theory and have attempted to apply simple microvascular decompression to the treatment of HMS, all of which have achieved a certain level of therapeutic effects ( 6 – 8 , 10 ). Wu et al reported on the surgical treatment of 10 HMS cases, and the findings showed that treatments with pure microvascular decompression or partial or complete resection of the trigeminal nerve motor branch were not all effective and did not prevent recurrences of spasms.…”

“…Wu et al reported on the surgical treatment of 10 HMS cases, and the findings showed that treatments with pure microvascular decompression or partial or complete resection of the trigeminal nerve motor branch were not all effective and did not prevent recurrences of spasms. Hence, the etiology of HMS remains unclear, and the possibility of a joint influence from both HMS and central factors cannot be ruled out ( 10 ).…”

“…Since the abnormal discharges in the muscles completely disappeared during spasms of the left masticatory muscles at that point, we did not completely resect the motor root to avoid dysfunction of the masticatory muscles. Wu et al reported of 3 HMS cases who underwent resection of the trigeminal nerve motor root, where the spasms disappeared following surgery, and there was no recurrence at 5 years of follow-up in two cases and no recurrence at 2 years of follow-up in one case; the patients only had mild atrophy of the masticatory muscles, and mouth opening was not restricted ( 10 ). Our patient only had mild atrophy of the temporalis and masseter muscles at 14 months after surgery, without any occlusal disorder.…”

Hemi Masticatory Spasm: Series of 7 Cases and Review of Literature

“…The exact role of microvascular decompression (MVD) of the trigeminal nerve root in patients with HMS is unclear. A few of the reported studies showed favorable outcome, but are of small sample size and with limited follow‐up …”

“…A few of the reported studies showed favorable outcome, but are of small sample size and with limited follow-up. 13,14 In this article, we want to highlight the rarity of the condition, male preponderance, long course of illness, association with FHA, scleroderma/morphea/LSA, and excellent response to BTX. Distribution of HMS remained the same for many years, during which time frequency and intensity of the spasms continued to increase.…”