Trigeminal neuralgia: the role of magnetic resonance imaging.

We present a case of an epidermoid cyst in contact with the inferior and lateral aspects of the left trigeminal nerve, which resulted in secondary trigeminal neuralgia of the left mandibular branch of the trigeminal nerve. The symptoms were typical of trigeminal neuralgia, with no other neurological signs and symptoms. If patients present with trigeminal neuralgia, consideration should be given to routine visualisation of the entire course of the trigeminal nerve by magnetic resonance imaging (MRI) to identify cases of secondary trigeminal neuralgia.