Medical Matters with Muiris Houston: Act fast to save face with Bell’s palsy

A patient’s wife, somewhat apologetically, came in to tell me that her husband had woken up the previous morning to find his face was paralysed on one side.

Mindful of the advice so effectively promulgated by the Irish Heart Foundation’s FAST campaign, she immediately called for an ambulance, thinking her husband had had a stroke. Both were much relieved to be told in the emergency department that the diagnosis was in fact Bell’s palsy.

Although she was still embarrassed by the fuss she had caused, I reassured her she had done the right thing. The F in the act FAST campaign stands for face – “Has the person’s face fallen to one side?” – and is designed to help people recognise stroke and to act promptly so that the patient gets time-sensitive treatment. But there are other causes, such as Bell’s palsy, that present in a similar way.

Bells palsy occurs following damage to the facial nerve. The nerve originates from the base of the brain and travels through a narrow, bony tunnel within the skull, exiting behind the ear.

It is thought that a virus, possibly the herpes simplex virus, may be responsible. When the nerve is irritated by the virus, it becomes swollen and inflamed. As a result, the impulses travelling to the face are blocked, leading to a weakness or paralysis of the facial muscles on one side of the face.

About one in 60 of us will be affected by Bell’s palsy over the course of our lifetime. The good news is that more than 70 per cent of patients make a full, spontaneous recovery, although this is more likely in those whose paralysis was partial rather than complete. But up to 30 per cent of Bell’s palsy patients are left with some degree of facial weakness.

High-dose steroids

This year, Canadian specialists came up with revised treatment guidelines for the condition. They recommend that all people with Bell’s palsy receive high-dose steroids in order to reduce involuntary facial spasm. Steroids are powerful anti-inflammatory agents, and help reduce the swelling around the facial nerve.

The guideline suggests an antiviral agent be prescribed along with the steroid in those with severe to complete facial paralysis, but not in patients with mild paralysis.

Physiotherapy helps those with persistent symptoms. Failure to protect the cornea among patients who are unable to blink adequately may result in corneal ulceration and permanent eyesight problems. So if your eye cannot close completely, it’s important to wear eye protection, and to use lubricants and ointments to keep the surface of the eye moist.

Unfortunately, up to one in six patients will be left with residual involuntary movements, while others may find their eye involuntarily tears up when they eat. This condition is known as Bogorad syndrome. If the branch of the facial nerve supplying a part of the inner ear is affected, there may be a loss of acoustic dampening, leaving the person with an intolerance of loud noise.

Writing in the current issue of the British Journal of General Practice, specialists from the University of Oxford make a plea for the earlier referral of Bell's palsy patients for facial reanimation surgery. The aim of the surgery is to reestablish facial symmetry. This is done by a procedure called cross-facial nerve grafting (CFNG): by using nerve grafts. Peripheral motor branches of the facial nerve on the other side of the face are joined to the corresponding branches on the affected side.

If it is carried out less than six to 12 months from the time the diagnosis is first made, success rates are quite good, leading the authors to suggest that cases of Bell’s palsy exhibiting residual symptoms after six weeks should be considered for referral to a plastic surgical facial reanimation service.

So it’s not just stroke patients who benefit from a quicker referral to secondary care than would have been the case some years ago.

mhouston@irishtimes.com muirishouston.com