Numbness of the face occurs due to some condition of the Trigeminal nerve. Some of the conditions which can affect it are: Infections
: Infections such as Herpes zoster
, Lyme disease, Sarcoid disease may cause numbness of this nerve. MRI of the region will usually show thickening of the nerve. An LP with cytology may be helpful. Pressure
: any cause of pressure on the nerve, such as with increased intracranial pressure, as in Benign Intracranial Hypertension. This will show up in an MRI.
Arnold Chiari malformation
: this may also cause kinking of the nerve. Tumours
: Tumours along the course of the nerve, from the pons to the periphery. Migraines
: A type of migraine without the associated headache, called 'migraine equivalents' may cause such symptoms. There are no specific tests for this, but trial with an anti-migraine drug will confirm this. Somatisation
: Finally, and most importantly, stress, depression, etc, can be the cause of this. If all others are ruled out, this is the condition to consider.
You should approach a Neurologist. He will need full neurological testing for reflexes such as the corneal reflex. He may also need an MRI and EEG. You can discuss these conditions with you neurologist.
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