Trigeminal neuropathy from perineural spread of an amyloidoma detected by blink reflex and thin-slice magnetic resonance imaging.

The purpose of this study was to describe a trigeminal neuropathy caused by the perineural spread of an amyloidoma. A 62-year-old woman had an amyloidoma of the Gasserian ganglion that was hypointense on T2-weighted images; the lesion was enhanced by gadolinium on thin-slice magnetic resonance imaging. There was no evidence of systemic amyloidosis or underlying inflammatory or neoplastic disorders. Her blink reflex and thin-slice magnetic resonance imaging demonstrated that the right trigeminal nerve was involved. A rare trigeminal neuropathy resulted from the perineural spread of a primary amyloidoma that was difficult to detect by conventional magnetic resonance imaging.