Hemimasticatory spasm caused by single venous compression of the root of the trigeminal nerve: An MRI study for a case report and review of literature.

ABSTRACT

Hemimasticatory spasm is a very rare disorder of the trigeminal nerve characterized by paroxysmal involuntary contraction of the jaw-closing muscles. Although its cause is not fully known, vascular compression of the trigeminal nerve is thought to be involved. Magnetic resonance imaging (MRI) can indicate continuing vascular compression for hemimasticatory spasm. Here, we report a case of hemimasticatory spasm that was caused by single venous compression of the trigeminal nerve root on MRI and was confirmed by microvascular decompression surgery.