Iatrogenic trigeminal sensorimotor neuropathy resulting from local anesthesia: A case report

Trigeminal neuropathy resulting from local anesthetic injection has not bee n reported in the literature. We present a 49-year-old man with 8 months of unilateral facial sensorimotor deficits in the distribution of the trigemi nal nerve, following a local anesthetic injection. His medical history was significant for resection of an ipsilateral tongue carcinoma 4 years earlie r with only postsurgical dysarthria and no other neurologic deficits. Magne tic resonance imaging of the head and face showed postsurgical changes and ipsilateral atrophic muscles of mastication without evidence of infection o r tumor recurrence. Electrodiagnostic evaluation revealed prolonged ipsilat eral R1, ipsilateral and contralateral R2 responses of the blink reflex, an d neurogenic electromyographic changes in ipsilateral masseter and temporal is muscles, consistent with ipsilateral trigeminal nerve injury. Although t rigeminal neuropathies from various etiologies have been reported, this uni que case offers another etiology to consider: iatrogrenic trigeminal neurop athy secondary to local anesthetic injection.