Microvascular Decompression of the Trigeminal Nerve

Microvascular Decompression (MVD) is a neurosurgical procedure used to treat trigeminal neuralgia, a pain syndrome characterized by severe episodes of intense facial pain and hemifacial spasm. Patients are put to sleep using general anaesthesia and are positioned on their back with their head turned or on their side with the symptomatic side facing up. Electrical monitoring of facial function and hearing is used. A straight incision is made two finger-breadths behind the ear about the length of the ear. A portion of the skull the size of a half-dollar is removed exposing the underlying brain covering known as the dura. The dura is opened to expose the cerebellum. The cerebellum is allowed to fall out of the way exposing the side of the brainstem. Using a microscope and micro-instruments, the arachnoid membrane is dissected allowing visualization of the 8th, 7th and finally the trigeminal nerve. The offending loop of blood vessel is then mobilized. Frequently a groove or indentation is seen in the nerve where the offending vessel was in contact with the nerve. Less often the nerve is thin and pale. Once the vessel is mobilized a sponge like material is placed between the nerve and the offending blood vessel to prevent the vessel from returning to its native position. After the decompression is complete, the wound is flushed clean with saline solution. The dura is sewn closed. The skull is reconstructed and the overlying tissues are closed in multiple layers. The patient is allowed to wake up and is taken to an intensive care unit or other close observation unit. Source: Wikipedia.org