[Diagnosis and treatment of the patient with trigeminal neuralgia]

Neuralgia of the trigeminus (NT) is the most common of cranial nerve neuralgias. Its diagnosis is entirely clinical and its most common form of presentation is well understood. Questions of differential diagnosis can emerge with certain entities such as atypical trigeminal neuralgia, short-duration unilateral neuralgiform cephalea of the trigeminus (SUNCT) arising from injection to the conjunctival, lacrimal or other glands, cluster headache, chronic paroxymal hemicrania, pain arising in the teeth and myofacial pain syndrome. The three main causative factors of NT are compression of the nerve root by an artery in the prepontine space, thereby creating an area of demyelinization, compression of the nerve by a tumor, and multiple sclerosis. The first is the most common of the three. NT can be classified as essential in 10 to 30% of patients. Recent advances in magnetic resonance (MR), and its advantages over other imaging systems, have made MR the diagnostic method of choice. The first treatment is medical and the basic drugs involved can be considered classic. Other therapies have been suggested in recent years, however, and should probably be studied further. Two substances stand out among those proposed: tocainide, an antiarrhythmic drug, and pimozide, an antipsychotic. Surgical treatment of NT can address either the cause (tumor or vascular compression) or symptoms, the latter being indicated when medical treatment fails. Surgery can be performed on peripheral nerves, on the gasserian ganglion and on the posterior fossa. The indications, outcomes and possible complications are quite different for each approach, making choice controversial.