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Bell’s palsy is a condition marked by temporary facial paralysis, and is the most common cause of facial paralysis, accounting for up to 80% of all cases in the UK.
What is Bell’s palsy?
Also known as idiopathic facial paralysis, Bell’s palsy is the sudden weakness of the muscles on just one side of the face. Bell’s palsy is a rare, non-life-threatening condition that usually goes away by itself, but can also be helped by some medications. The weakness of the muscles in the face causes one side to droop, which is the most noticeable symptom. The condition takes its name from Scottish surgeon Charles Bell, who noted the condition and its relation to the nerves in the face.
What causes Bell’s palsy?
The cause of Bell’s palsy is not known, though it is thought that certain health conditions and viral infections could trigger the onset. In its technicality, the condition is triggered by inflammation that causes pressure on the nerve that is responsible for the function of the facial muscles, cranial nerve VII, making it harder to exert control over the muscles. Symptoms start to disappear as the swelling reduces.
It is believed that the pressure sits on the nerve at the point where it leaves the skull, intercepting the neural messages or simply causing damage to the nerves.
What are the signs and symptoms of Bell’s palsy?
The symptoms of Bell’s palsy are not particularly gradual; they appear suddenly, often within 48 hours. For some people, symptoms are not too severe, whereas for others, facial muscle weakness can be extreme. For most people, symptoms will be completely gone within three months, but for many, they can disappear within weeks.
- Drooping on one side of the face.
- Pain in the face and/or the ear.
- Loss of or a change in taste.
- Issues with speaking.
- Issues with drinking.
- Dry eyes due to not being able to close the eyelids.
- Hyperacusis, a low tolerance for noise which can cause pain.
The most common side effect is facial paralysis on one side, which happens in up to 70% of people with the condition.
Many people who have Bell’s palsy may confuse their symptoms with that of a stroke, due to the paralysis of one side of the face, but the two conditions are entirely different in that a stroke can be immediately life-threatening. Furthermore, symptoms of a stroke do not usually solely affect the facial muscles, but muscles on an entire side of the body. However, if someone has symptoms that mimic that of a stroke, they should seek medical attention immediately.
How long does Bell’s palsy last?
Bell’s palsy is a temporary condition, and with rest and taking some time to recover, symptoms should start to disappear within three weeks. Many people will have recovered after three months, with six months being the full time of recovery. It is important to remember that whilst Bell’s palsy is not life-threatening, the condition indicates that there may be some swelling and inflammation present. It should be considered that whilst you may not feel physically unwell, you need to rest.
Up to 80% of people with Bell’s palsy will make a full recovery, whilst the remainder of people will sometimes have longer-term symptoms, which are mostly facial drooping.
What are the risk factors for Bell’s palsy?
There is no disparity in gender when it comes to Bell’s palsy.
People are at higher risk of Bell’s palsy if they have:
You are also three times more likely to have Bell’s palsy if you are pregnant, particularly in the last trimester. This is thought to be due to the risk of high blood pressure, gestational diabetes and inflammation. Treatments for Bell’s palsy should be carefully considered, as the risk of premature birth when taking steroid medication is higher.
The herpes virus is responsible for a large number of cases of Bell’s palsy, accounting for up to 44% of cases.
It is not likely that you will get Bell’s palsy again if you have had it once, although if you do, it is more likely to occur again within two years of the first instance, and affect either side of the face.
Can Bell’s palsy be prevented?
There is no way to prevent Bell’s palsy that is currently known, although perhaps avoiding the conditions that are known to be a potential trigger as listed above.
How is Bell’s palsy diagnosed?
There is no single test to diagnose Bell’s palsy, so it is diagnosed by a process of elimination of other conditions. In the first case, a stroke will be ruled out, followed by blood tests to rule out other conditions and infections.
A doctor will carry out a physical examination of the face and the body, focusing their attention on the facial muscles, asking you to try and move different muscles and features like the eyelids. Eyelids that don’t close, with eyes rolling upwards and to the side, suggest that the condition is Bell’s palsy. If they are unsure after this, they will also carry out tests that can measure the electrical activity within the muscles, which can show whether the muscles are functioning properly. A conclusion is usually reached quite quickly as to whether the condition is Bell’s palsy.
Nerve damage can be measured using a House-Brackmann score, which is a score that describes the extent of damage to a facial nerve. This score is reached by measuring the movement of the eyebrow in an upwards direction, and the movement of the mouth in an outward direction. A point is given for every movement of 0.25cm, with a score out of 8. The score can then be used as a predictor for the lengths and extent of recovery in someone with Bell’s palsy. A score of 8/8 indicates that function is normal, with 1/8 indicating severe impact on facial movement, and a slower recovery period.
In some cases, the doctor might order a scan of the brain to ensure that there is no growth that may be causing pressure or swelling in the brain, which can push on the nerves that control the facial muscles.
Sometimes, Bell’s palsy is also confused for Lyme disease and Ramsay Hunt syndrome, so doctors may carry out tests to exclude these conditions as well. Other causes of paralysis in the face include meningitis, an injury to the head, inflammatory diseases, diabetes and severe HIV infection.
How is Bell’s palsy treated?
Many people with Bell’s palsy do not receive treatment, but there are treatments available that can quicken the process of recovery.
A doctor may prescribe a short treatment of steroids, which could help to reduce the swelling and improve the function of the nerves, which could reduce the length of time you are affected by Bell’s palsy. If it is suspected that the condition was onset by the presence of a viral infection, the doctor will likely prescribe antiviral medication, alongside the steroidal medication, which can help with the recovery process.
- Corticosteroids which serve to reduce the inflammation in the nerves, and are most effective when administered within 72 hours
- Antiviral medications such as acyclovir or valacyclovir, which are administered for people where Bell’s palsy has been triggered by the herpes virus.
As you may not be able to blink or close one of your eyes, you may be given lubrication for the eyes, namely eye drops, and a covering for the eye to avoid it being contaminated. In rare instances, operative measures may be required to correct more severe, long-term side effects of the condition, though this comes with its own risks of loss of hearing and further damage to the nerves.
Physiotherapy may also be suggested as a means of treatment, as it can help to strengthen muscles and retain muscle tone. As a muscle becomes paralysed, it is important that the muscle is retaught its normal movement through exercises, so that the muscles are not permanently affected when the nerves regain their function.
Some people choose to follow alternative methods of treatment such as acupuncture.
Who can provide support with Bell’s palsy?
- Facial palsy is a charity dedicated to improving the lives of people affected by Bell’s palsy, including specialist help, information on conditions that may be confused for Bell’s palsy, self-help videos, and support for clinicians.
- The Brain Charity provides support for people living with neurological conditions, including Bell’s palsy. They provide information, practical support and emotional support.
- Bell’s Palsy UK provides useful information and resources, an online forum and support for people who have been affected by Bell’s palsy.