Neuralgia, trigeminal - Diagnosing trigeminal neuralgia

As the pain caused by trigeminal neuralgia is often felt in the jaw, teeth or gums, it is common for people to visit their dentist initially, rather than their GP.

If you visit your dentist, they will ask you questions about your symptoms and investigate your facial pain using a dental X-ray and other means to look for other more common causes, such as a dental infection or cracked tooth.

If the dentist cannot find a cause, it is important not to undergo unnecessary treatment such as a root canal filling or an extraction, even though you may be convinced that it is a tooth problem. If your dentist cant find anything wrong, do not try to persuade them to remove a particular tooth, as this will not solve the problem.

Often, the diagnosis of trigeminal neuralgia is made by a dentist, but if you have already seen your dentist and they have not been able to find an obvious cause of your pain, visit your GP.

Seeing your GP

There is no specific test for trigeminal neuralgia, so a diagnosis is largely based on your symptoms and your description of the pain.

If you have experienced facial pain, your GP will ask you questions about your symptoms, such as how often they occur, how long the pain attacks last and which areas of your face are affected. The more details about your pain you can provide, the better.

Your GP will consider other possible causes of your pain and may also examine your head and jaw to identify which parts are painful.

Ruling out other conditions

An important part of the process of diagnosing trigeminal neuralgia involves ruling out other conditions that can also cause facial pain.

By asking about your symptoms and carrying out an examination, your GP may be able to rule out other conditions, such as:

migraine
joint pain in the lower jaw
giant cell arteritis (temporal arteritis) – a condition in which medium and large arteries in the head and neck become inflamed and cause pain in the jaw and temples
a possible injury to one of the facial nerves

Your medical, personal and family history will also need to be taken into consideration when determining possible causes of your pain.

For example, trigeminal neuralgia is less likely if you are under 40 years old, and multiple sclerosis (MS) may be more likely if you have a family history of the condition or if you have some other form of this condition. However, trigeminal neuralgia is very unlikely to be the first symptom of MS.

MRI scans

If your GP is not sure about your diagnosis, or if you have unusual symptoms, they may refer you for a magnetic resonance imaging (MRI) scan of your head.

An MRI scan uses strong magnetic fields and radio waves to create detailed images of the inside of your head. It can help identify potential causes of your facial pain, such as sinusitis (inflammation of the lining of the sinuses), tumours on one of the facial nerves, or nerve damage caused by MS.

An MRI can also sometimes detect whether a blood vessel in your head is compressing one of the trigeminal nerves, which is one of the main causes of trigeminal neuralgia. However, highly sophisticated MRI scans may be needed to show this accurately, although this may not necessarily be helpful, because not everyone with a compressed trigeminal nerve has trigeminal neuralgia.