Microvascular decompression for trigeminal neuralgia in patients with multiple sclerosis

BACKGROUND Microvascular decompression (MVD) of the trigeminal nerve is a well-established procedure for the treatment of idiopathic trigeminal neuralgia. Multiple sclerosis (MS) has long been considered a contraindication for this procedure, due to the known polycentric nature of the disease. Medical treatment followed by percutaneous procedures provide relief for the great majority of these patients. There exists a small subgroup of patients with trigeminal neuralgia who are diagnosed with MS only after a microvascular decompression procedure has been performed. Furthermore, management of the patient with known MS whose pain continues to recur, despite maximal medical therapy and multiple percutaneous procedures, can be exceedingly difficult. METHODS Five patients with MS, three who had undergone multiple unsuccessful percutaneous procedures and two in whom the diagnosis of MS had not been established, underwent exploration of the cerebellopontine angle. Three patients underwent MVD alone, and two (both with known MS) underwent MVD and partial section of the trigeminal nerve. RESULTS Patients who underwent microvascular decompression alone did not have satisfactory relief of pain. Patients who underwent partial sectioning of the nerve did better. CONCLUSIONS Patients with MS and symptoms of typical trigeminal neuralgia may benefit from exploration of the cerebellopontine angle and partial sectioning of the nerve. MVD alone fails to provide adequate or reliable relief of pain.