Hemifacial spasm (HFS) is a neuromuscular disease in which the patients suffer from irregular, involuntary muscle contractions (spasms) on one side of the face. The hemifacial spasm occurs among both men and women but is more common among middle aged and elderly women.
Hemifacial means half of the face. The facial nerves that control all facial activity start from the brain and go through many structures to reach the face, carrying signals from the brain to contract or relax facial muscles. Facial nerves are responsible for facial actions like blinking, twitching the nose and moving the lips.
Types of hemifacial spasms
In this most common hemifacial spasm the twitching usually starts in the lower eyelid in the orbicularis oculis muscle. But it spreads to the whole lid and to the orbicularis oculis muscle around the lips and buccinators muscle of the cheekbone area over time.
Atypical hemifacial spasms
These spasms occur rarely in 2-3% of the patients and have the reverse process – they start at the orbicularis oris muscle around the lips and cheekbone in the lower face and progress up to the orbicularis oris muscle in the eyelid over time.
Causes of hemifacial spasms
Hemifacial spasms are usually caused by a nerve injury, tumour, vascular compression, facial nerve compression by mass, brainstem lesions including stroke or multiple sclerosis plagues, any serious trauma, or even without any apparent cause.
Hemifacial spasms are not hereditary. Though it is not common, spasms might occur in both sides of the face too.
Symptoms
The symptoms of HFS usually begin around the eye. They begin in smaller levels and gradually become worse and sometimes permanent. The left side has more probability of being affected than the right side. The twitches then may spread to involve other muscles on the same side of the face, including the mouth and jaw. If the spasm becomes permanent, the corner of the mouth can be lifted and feel permanently pulled up and the jaw bones might also click.
Based on the severity of the condition, the effects of the hemifacial spasms might be anywhere between mildly inconvenient twitching or even affect vision and concentration. The spasms have also been noted to worsen while the patients are tired or stressed.
Botolinum Toxin (Botox) for hemifacial spasms
Botox injections are one of the widely used treatment methods. When injected in controlled doses, botolinum toxin can be used to relax the excessive muscle contraction and reduce the intensity of the spasms.
Botox is injected into the facial muscles, effectively blocking the signals from the nerve. It the signals for twitching are absent, the twitching reduces and the spasms also stop gradually. The effects of a Botox injection begin to work within a few days and last for two to three months. The side effects, if any, like the drooping of eyelid and double vision wear off after 1 or 2 weeks.
Surgery for hemifacial spasms
The surgeons use many surgery options for hemifacial spasms treatment. Microvascular decompression – that involves removing the blood vessel that may be pressing on the facial nerve, though curative, is not an effective method for patients with hemifacial spasms due to the serious side effects. This is one of the main reasons why surgery is used as the last option in case of the extreme spasms that cannot be controlled by other treatment methods and if the patient is particularly young.
Benign essential blepharospasm (BEB)
Blepharospasm is the involuntary closure of both eyelids. Benign essential blepharospasm (BEB) is a condition where there is an excessive eye twitching, spasm in eyelids or abnormal blinking. The signs and symptoms of Benign essential blepharospasm (BEB) appear in middle to late adulthood and worsen with time.
The exact causes of blepharospasm cannot be pointed out but functional neuroimaging tests have suggested dysfunctions with basal ganglia and sometimes even genetics.
The first symptoms of Benign essential blepharospasm (BEB) include increased frequency of blinking, dry eyes, eye irritation that is aggravated by wind, air pollution, sunlight and other external irritants. The symptoms and Benign essential blepharospasm (BEB) may affect one or both eyes and the spasms of the eye muscles might cause involuntary winking or squinting. Benign essential blepharospasm (BEB) might lead to difficulties in keeping the eye open and lead to vision impairment.
Orbicularis myokymia
Orbicularis myokymia is a spontaneous, fine fascicular contraction of muscle without muscular atrophy or weakness. Orbicularis myokymia happens because of contractions of the orbicularis oculi muscle. Orbicularis myokymia typically affects one of the lower eyelids. If multiple eylids are involved, the contractions of each eyelid are independent of each other.
Orbicularis myokymia is benign, self limited and not a medically serious disease. Orbicularis myokymia occurs as a precursor of hemifacial spasm, blepharospasm, or multiple sclerosis.
Dr. Debraj Shome is a trained surgeon who has performed many cosmetic and medical surgeries. He has a lot of successful testimonials for treating blepharospasm, hemifacial spasms and other diseases involving facial structures