Hemifacial Spasm
Hemifacial spasm is a severe and involuntary twitching or spasm involving one side of the face. It classically begins around the eye and then slowly spreads to involve all the muscles on that side of the face. Patients become distressed and embarrassed by the uncontrollable nature of the tic or spasm.
Treatment options are limited. Regular Botox injections aimed at weakening the facial muscles and decreasing the spasm can help for a while. Prolonged spasm and repeated Botox injections eventually lead to muscle damage and permanent weakness of facial muscles.
The usual cause of hemifacial spasm is compression of the nerve as it exits the brain stem by a blood vessel (usually an artery, occasionally a vein). An MRI scan is always essential as some cases are caused by other conditions, including skull base tumours (meningiomas, schwannomas, epidermoids, cancers).
Surgery for hemifacial spasm due to vascular compression should be done by a specialist skull base neurosurgeon, as the approach is identical to that used for tumours at the skull base in the cerebello-pontine angle. The surgery is known as a MicroVascular Decompression (MVD). It involves making a hole in the skull behind the ear, opening the lining of the brain (dura) and inspecting the origin of the facial nerve using the microscope for magnification and illumination. In most cases a blood vessel, usually an artery, sometimes a vein, is found to be compressing the origin of the nerve. The vessel is carefully moved away from the nerve. It is held away with one or more small pieces of woven fabric (Teflon), which remains in place and cushions the nerve from the vessel.
The surgery is successful in more than 85% of cases and allows the patient with severe Hemifacial spasm to continue a normal life free of this most severe and embarrassing affliction.
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