Hemimasticatory spasm. Own experience of using botulinum neuroprotein type A

Abstract

Нemimasticatory spasm (HMS) is a rare disorder of the nervous system, in which there are unilateral, violent spasms of the masticatory muscles innervated by the motor portion of the trigeminal nerve. The causes of HMS remain largely unexplored, but microvascular compression is most likely. Anticonvulsants, surgical treatment and botulinum therapy can be applied for the treatment of HMS.We presented a clinical case of HMS in a 38-year-old woman who had been suffering from this disease for 18 years. The diagnosis of HMS was established only 10 years after the first visit to the doctor. Spasms could occur up to several hundred times a day with a duration up to 15 seconds. The magnetic resonance imaging allowed to exclude neurovascular conflict. Electroneuromyography revealed axonal lesion of the right trigeminal motor root and spontaneous activity in the right masseter muscle. Anticonvulsant treatment was ineffective. The patient received botulinum therapy with a good treatment result.

Hemimasticatory spasm: a series of 17 cases and a comprehensive review of the literature

“…In 10 patients, HMS developed a mean of 3.7 ± 3.4 years after the onset of Parry–Romberg syndrome; in five cases, it developed simultaneously; and in three cases, it developed a mean of 1.6 ± 1.2 years before the onset of HMS. In three cases, the symptoms worsened during pregnancy and were relieved after childbirth ( 21 , 35 , 47 ). The silent period was not elicited during spasms in 28 patients (23.9%).…”

“…Although the underlying mechanisms of HMS remain unclear, some possible etiologies include deep tissue changes caused by Parry–Romberg syndrome or scleroderma ( 13 , 17 ), injury to or inflammation of the peripheral nerve ( 64 ), and pregnancy-related hormonal changes ( 21 , 35 , 47 ). Scleroderma is an autoimmune disease in which an overproduction of abnormal collagen results in normal tissues being replaced with scar tissue.…”

“…Recently, dental or oral surgical treatments have been reported to precede HMS ( 64 ). Three cases of HMS worsened during pregnancy and improved after childbirth ( 21 , 35 , 47 ). Thus, pregnancy-related hormonal changes can influence the mechanism responsible for HMS.…”

“…Involuntary movements can cause muscle pain, tongue or buccal mucosa biting ( 9 , 18 , 21 , 25 , 34 , 35 , 55 ), and temporomandibular joint dislocation ( 6 , 18 , 54 ), resulting in masticatory disturbances or dysarthria. HMS is occasionally accompanied by hemifacial atrophy or localized scleroderma ( 1 , 2 , 7 , 10 , 13 , 15 , 17 , 25 , 43 , 47 , 51 ). Scleroderma is a chronic connective tissue disease characterized by skin lesions.…”

“…The mechanism underlying HMS remains unclear, although vascular compression or focal demyelination of the trigeminal nerve has been considered a plausible etiology ( 8 , 11 – 13 ). There are some options for the treatment of HMS, including oral medication, botulinum neurotoxin (BoNT) therapy ( 12 , 13 , 15 , 17 , 19 , 21 , 22 , 24 , 25 , 27 , 28 , 34 , 36 , 38 , 39 , 42 – 45 , 47 , 49 ), and microvascular decompression of the trigeminal motor root ( 31 – 33 , 39 – 41 , 50 ). BoNT injection into the affected muscles is believed to be the most effective option.…”