An Unusual Case of Simultaneous Bilateral Trigeminal Neuralgia Due to Multiple Sclerosis.

Although several reports have indicated that trigeminal neuralgia related to multiple sclerosis may occur bilaterally in the orofacial region, trigeminal neuralgia pain usually involves the two sides in different time lapses, and the simultaneous involvement of trigeminal territories on both sides is commonly considered incompatible with its diagnosis. This case report describes a patient with bilateral trigeminal neuralgia related to multiple sclerosis that started simultaneously on both sides of the orofacial region. A 55-year-old man presented with a 16-year history of relapsing/remitting multiple sclerosis. For 1 year, the patient had been complaining of electric shock-like, paroxysmal pain of severe intensity that lasted from a fraction of a second to a few minutes and involved the first and second trigeminal divisions of both sides simultaneously. The neurophysiologic testing of trigeminal reflexes showed bilateral delayed latencies of reflex responses compatible with a trigeminal afferent pathway impairment related to multiple sclerosis. A dedicated 3T magnetic resonance imaging scan revealed pontine demyelinating plaque and a bilateral neurovascular conflict at the trigeminal root entry zone. The finding of an unusual case of simultaneous bilateral trigeminal neuralgia due to multiple sclerosis should prompt neurologists to consider a diagnosis of trigeminal neuralgia in patients with multiple sclerosis in cases of simultaneous involvement of trigeminal territories on both sides.