Eyelid Twitching

The medical term for excessive eye twitching is hemifacial spasm (HFS) or ticconvulsif. This, essentially, is an involuntary contraction (or twitch) of the facial muscles, albeit on one side of the face. Hemifacial spasm is usually due to irritation of the facial nerve that controls the movement of muscles around the eyes, eyelids, mouth and lips.

In approximately 90% of cases, eye twitching starts near the eye before gradually progressing down the face. In the remaining 8% to 10% off patients, it begins near the chin and moves up towards the eye area. While the twitching is not painful, it can cause undue embarrassment and self-consciousness as it begins to interfere with normal facial expressions and vision.

Hemifacial spasm is a rare condition in the developed world with as few as 8 in 100,000 people being affected. In the UK alone, it is thought that there are 4,000 who suffer from hemifacial spasm. It typically manifests itself around 45 years of age and is slightly more common in women.

What causes hemifacial spasm?

Excessive eye twitching can be caused by an injury to the facial nerve which controls the facial muscles. It may also arise from a tumour or blood vessel which is pressing against the nerve. The compression causes the nerve to misfire and, thereby, causes the facial muscles to contract.