Characteristics of nocturnal facio-mandibular myoclonus in four middle-aged patients

A rare case of tongue biting during sleep in childhood

Bleeding tongue-biting episodes during sleep are a rare and alarming situation that can negatively impact the child's and parents' sleep, affecting their quality of life. Although highly suggestive of epilepsy, a differential diagnosis should be made with sleep-related movement disorders such as bruxism, hypnic myoclonus, facio-mandibular myoclonus, and geniospasm when this hypothesis is excluded. The clinical history, electroencephalogram, and video-polysomnography are essential for diagnostic assessment. Treatment with clonazepam can be necessary in the presence of frequent tongue biting that causes severe injuries and sleep disturbance. This study reports the challenging case of managing and diagnosing a 2-year-old boy with recurrent tongue biting during sleep since he was 12 months old, causing bleeding lacerations, frequent awakenings, and significant sleep impairment with daytime consequences for him and his family.

CITATION

Cascais I, Ashworth J, Ribeiro L, Freitas J, Rios M. A rare case of tongue biting during sleep in childhood. J Clin Sleep Med. 2024;20(4):653-656.

Tongue Biting Event in Patients with Sleep-Related Facial Mandibular Myoclonus: A Case Series Study

Background

Sleep-related facial mandibular myoclonus (SRFMM) remains rare in clinical practice. The aim of this study was to provide a comprehensive understanding of the electroclinical manner, therapeutic regimen, and prognosis of SRFMM.

Methods

Twenty-three patients who were diagnosed with SRFMM by clinical manifestation, video-electroencephalography (EEG) and electromyography over bilateral masseter and temporalis muscles were enrolled. Clinical and electrophysiological evaluation as well as follow-up information were recorded and analyzed.

Results

The cohort involved 4 infants and 19 adults with a mean onset age of 43.5 years for SRFMM, among whom 19 were male. Twenty-one patients complained of tongue injuries and disturbed night-time sleep. SRFMM in 4 patients were ascribed to oral aripiprazole, brainstem ischemia and brain trauma. In 62 SRFMM episodes, 93.5% occurred in NREM sleep and 6.5% in REM sleep, and all events were associated with EEG arousals. In 13 patients with or without clonazepam, the motor events gradually disappeared, and the rest turned to be sporadic.

Conclusion

SRFMM is a characteristic parasomnia manifested by tongue biting and accompanying facial mandibular myoclonus, leading to disrupted sleep. Besides adults, infants can also experience SRFMM with spontaneous remission. Most patients respond well to clonazepam, eventually with favorable prognosis.