Trigeminal Neuralgia - Causes

Authored by Dr Colin Tidy, 12 May 2017

Patient is a certified member of
The Information Standard

Reviewed by:
Dr Adrian Bonsall, 12 May 2017

The trigeminal nerve (also called the fifth cranial nerve) is one of the main nerves of the face. There is one on each side. It comes through the skull from the brain, in front of the ear. The trigeminal nerve splits into three main branches. Each branch divides into many smaller nerves:

  • The nerves from the first (ophthalmic) branch go to your scalp, forehead and around your eye.
  • The nerves from the second (maxillary) branch go to the area around your cheek.
  • The nerves from the third (mandibular) branch go to the area around your jaw.

The branches of the trigeminal nerve take sensations of touch and pain to the brain from your face, teeth and mouth. The trigeminal nerve also controls the muscles used in chewing and in the production of saliva and tears.

Cross-section of the head showing the trigeminal nerve and its branches

Usually one or both of the maxillary and mandibular branches are affected by trigeminal neuralgia. It is uncommon for only the ophthalmic branch to be affected. Only about 3 in 100 cases of trigeminal neuralgia affect both sides (are bilateral). It is much more common for people with bilateral trigeminal neuralgia to have other people in their family affected by the condition.

In about 80-90 out of 100 cases of trigeminal neuralgia it is thought that the cause is pressure on the nerve (compression) by a loop of artery or vein. Much more rarely, trigeminal neuralgia is a symptom of another condition, like a tumour, multiple sclerosis, or an abnormality of the base of the skull. In some cases, the cause is not known.

Further reading and references

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