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What is Hemiplegic migraine and explain in detail?
== Symptoms and signs ==
Hemiplegia (Greek hemi = Half), is condition that affects one side of the body. Signs of a hemiplegic migraine attack are similar to what would be presented in a stroke that typically includes sudden severe headache on one side of the brain, weakness of half the body, ataxia and aphasia which can last for hours, days or weeks.

Cause
Diagnosis
Classification
The ICHD classification and diagnosis of migraine distinguish 6 subtypes of hemiplegic migraine. Familial hemiplegic migraine (FHM) can be loosely divided into two categories: with and without cerebellar signs. Cerebellar signs refer to ataxia, sometimes episodic and other times progressive, that can accompany FHM1 mutations and is caused by degeneration of the cerebellum. These cerebellar signs result in a phenotypic overlap between FHM and both episodic ataxia and spinocerebellar ataxia