This is an information leaflet available to my patients and does not imply that this is appicable to you or your Consultan'ts practice. Not everyone would agree with all the statements made here, so if you have this condition, or think you have, you need to consult your own doctor.
An Information Leaflet
What is Trigeminal Neuralgia?
This is a condition, which is characterised by very severe facial pain. it is worse than a labour pain - I'm told. The particular features of this condition are that the pain is almost always confined to one side of the face and it occurs out of the blue without any obvious cause and does not go away by itself in thelong term.
Trigeminal Neuralgia is diagnosed mainly from the patient’s story. The pain typically occurs on one side of the face and may involve the upper, middle or lower thirds of the face, sometimes two thirds of the face and occasionally the whole of one side.
The character of the pain is that it is a very sharp pain, often described as feeling like ‘ red hot needles ‘ and the jabs of pain last for seconds or minutes and are of sudden onset. The pain may occur so suddenly that it can make the patient jump when it occurs.
Another feature of Trigeminal Neuralgia is that there is often a trigger spot on the face or in the mouth which if touched can start the pain off. The pain can also be provoked by touch, cold, washing the face, eating and talking. Unfortunately this can drive patients to despair and some patients loseweight and may even avoid social contact.
You do not need to have all of these features to have Trigeminal Neuralgia but usually most of them are present. Dull pain that spreads across the mid-line of the face and does not have typical provoking features is not Trigeminal neuralgia. If you have doubts about the type of pain that you are suffering, discuss this with your consultant.
We do not know for certain what the underlying cause of this painful condition may be. There are however theories about the cause, which seem to fit the facts and offer a chance of long-term treatment.
The nerve that supplies one half of the face and part of the scalp comes from the lower part of the brain at the back. It is thought that where the nerve enters the brain (the Root Entry Zone) a blood vessel lies incontact with the nerve and this ‘vascular compression’ causes the pain.
This seems to be correct as the vast majority of patients that we operate upon do have this problem, inthis area. Unfortunately only 90% ofpatients do have a demonstrable vessel causing the pain at operation so we arenot 100% certain that our theory is correct.
There are other causes of Trigeminal Neuralgia such as pressure from tumours or inflammatory conditions of the nervous system but most of these other causes can be excluded by doing abrain scan before planning treatment.
Treatment of TrigeminalNeuralgia is divided up into medical and surgical treatment.
The mainstay of medicaltreatment is to give drugs that are normally used in the treatment ofepilepsy. These particular drugs slowdown nervous tissues ability to transmit the electrical impulses, which allowsnerves to function. The most effectiveof these is Tegretol (carbamazepine) which can be prescribed in doses up to1200 milligrams / day. Other drugs suchas Epanutin (phenytoin) and Epilim (sodium valproate) can also be used. Usually the pain is controlled by a smalldose of Tegretol and other treatment is not needed, as this drug is usuallywell tolerated and safe for long-term use. The other drugs tend to be used if the patient does not tolerate theTegretol for one reason or another. Ifthe drugs don’t work there are surgical options that can be considered.
A number of surgicalprocedures are available each with particular advantages anddisadvantages. Your surgeon will be ableto tell you which is the most suitable treatment in your individual case.
There are four basic waysto treat this condition:
1. A needle is placed under local or sometimes a generalanaesthetic into the area where the nerve comes out of from the skull usingx-ray control. A small amount ofglycerin is then injected after which the patient has to keep still with thehead held forward for about 5-6 hours to allow the glycerin to do it’s job (notall surgeons feel that keeping the head still in this way is necessary). It works by dehydrating the nerve and causingit mild damage and this reduces its ability to transmit pain. This is a good treatment but the effects lastonly from 6 to 24 months usually.
2. Instead of injecting anything into the nerve an electricalneedle can be inserted into the nerve and used to cauterize the nervepartially. The needle placement is mademore precise by being able to stimulate the nerve to produce a gentle tingleand when this is in the place where the patient has the pain that particularportion of the nerve can be heated up electrically. This is a good treatment but suffers from thedisadvantage that it leads to a degree of permanent numbness of the face andalso a kind of after pain can result (in 5-10%) which can be very difficult totreat. It does however give good longterm relief of pain and only 15-20% of patients get the pain back in the longterm.
3. The nerve can be cut. This is usually done by an open operation and usually results incomplete facial numbness on that side of the face. This is only ever done as a last resort asthe numbness of the eyeball that results can produce serious problems withvision in the long term.
4. The above treatments all work by damaging the nerve and theonly treatment that we have which is non-destructive is an operation called ‘micro-vascular decompression’.
Microvascular decompression is a relatively new operation that has been used now for about thirty years. A small opening is made at the back of the skull and the edge of the brain is gently lifted aside. The Trigeminal nerve is identified and usinga microscope is examined for contact with a blood vessel, which is gentlylifted away from the nerve and held away with a special tiny sponge.
This effectively stops the pain in more than 97% of cases and leads to a permanent cure in approximately 90% of patients. Thisoperation has the advantage that it is very effective and does not damage the nerve and return of the pain is rare. Numbness following surgery is usually temporary however 15% of patients get some permanent loss of feeling in the face.
Shortly before admissionto hospital, it is likely that you will be seen in a pre-admission clinic whereyour general fitness for the anaesthetic is assessed. You may need a chest x-ray, ECG (a hearttracing) and some blood tests.
When you are admitted to hospital, surgery is usually carried out the following day. Most patients are given an injection or tablets before surgery to relax them (pre-med). The anaesthetist who puts you to sleep will visit the day before surgeryto decide on this and on your general fitness for the anaesthetic.
On the day of surgery you will be taken to the anaesthetic room in the operating theatre and given an injection to make you sleep during the operation, after which you will awaken on the Neurosurgical Ward.
Microvascular decompression is generally a safe procedure and can be carried out at almost any age. The oldest patient operated on in Middlesbrough with this operation was aged 89 and did extremely well!
You can expect to be in hospital for a minimum of five days, unless some complication arises. One of the risks of this operation is that when manipulating blood vessels in the base of the brain a stroke might occur. We have not had such a case in the last 10 years however.
Occasionally the fluid, which bathes the brain, can leak into the wound and require a further small operationto repair the defect in the brain's coverings. This is an uncommon event but should your wound leak any fluid or othermatter following surgery it is important to inform your doctor.
Because other nerves are close to the Trigeminal nerve they can be affected by the surgery. This is very rare but there have been cases of weakness in the muscles of one side of the face temporarily, temporary double vision, temporary unsteadiness when walking and mild deafness on the side of the operation.
On your return home you are unlikely to feel like doing your own cooking cleaning or shopping for at least a few weeks. It is important thatyou should have a friend or relative staying with you during that time to look after you during your convalescence. If this is impossible, discuss the matter with the ward sister in the pre-assessment clinic or when you are admitted to the ward.
Following the surgery you should not be in any severe pain. If youare, you should consult your GP or telephone the ward.
If the wound becomes red, painful, tender or swollen or discharges any matter it is important you should either telephone your GP or the ward.
The wound will either have staples to close the skin or a dissolvable stitch buried under the skin. Ask the ward staff to advise you about this before you go home, as the staples should be removed between five and sevendays. You should avoid the wound getting wet during the first week after surgery. However, if the wound becomes wet when you wash your hair for example, you are unlikely to come to any harm and it can just be dabbed dry with a clean towel.
Most patients have returned to normal activities such as work and driving between six weeks and three months but this varies according to the patient’s age.
A normal sex life can beresumed within two or three weeks.
If the surgery is successful you can say goodbye to the anti-convulsant drugs as soon as youawaken after the operation.