Trigeminal Neuralgia

Classical (Idiopathic) TN

The most common form. Caused by compression of the trigeminal nerve root entry zone by an aberrant loop of blood vessel — most commonly the superior cerebellar artery. Over time, this pressure wears away the nerve's protective coating, which causes the nerve to misfire and send pain signals.

Secondary TN

A small proportion of TN cases are secondary to an underlying structural cause, such as multiple sclerosis (MS), cerebellopontine angle tumour (acoustic neuroma, meningioma), or arteriovenous malformation (AVM). Dedicated MRI investigation excludes these secondary causes and guides treatment planning.

The pain of trigeminal neuralgia is very distinctive:

• Sudden, severe, electric shock-like or stabbing facial pain
• Brief duration — episodes last from a fraction of a second to a few minutes
• Unilateral — always (or almost always) on one side of the face
• Triggered by light stimulation — touching the face, chewing, talking, brushing teeth, wind, or even eating can precipitate attacks
• Pain-free intervals — patients are typically completely free of pain between attacks (distinguishing TN from other facial pain conditions)

As the condition progresses some people develop a constant facial pain in the background, on top of the sudden attacks. This form of the condition can be harder to treat. The fear of triggering pain can cause people to avoid eating, speaking, or washing their face. This can lead to weight loss and withdrawal from social activities.

Trigeminal neuralgia can usually be diagnosed based on the description of the pain alone. Imaging is necessary to exclude secondary causes of TN.

• An MRI brain with dedicated sequences (high-resolution imaging of the trigeminal nerve and vascular structures) is performed to identify vessel-nerve contact and to exclude secondary causes such as MS, tumour, or AVM.

A positive response to carbamazepine (Tegretol) is also strongly supportive of the diagnosis.

Medical (Pharmacological) Management

Medications are the first step in treating trigeminal neuralgia and may be commenced by your GP or neurologist.

• Carbamazepine – the first-line treatment. It works by stabilising nerve membranes. A clear response to carbamazepine helps confirm the diagnosis.
• Other medications such as oxcarbazepine, baclofen, gabapentin, and pregabalin may be used if carbamazepine is not suitable or not workin well enough on its own.

Medications control pain well for most people to begin with. However, over time some people find the medications stop working, cause side effects, or need to be combined with other treatments.

Microvascular Decompression (MVD)

MVD is the only treatment that fixes the underlying cause of trigeminal neuralgia. It is the most effective and longest-lasting surgical option.

During the operation, a small opening is made in the skull behind the ear. Using a microscope, the surgeon gently moves the blood vessel that is pressing on the nerve and places a small soft pad between them to stop the pressure. MVD achieves immediate, complete pain relief in approximately 80–90% of patients, with sustained long-term freedom from pain in 70–80% at 10 years.

MVD is the preferred treatment for classical TN where imaging demonstrates vascular compression. At One Brain and Spine, our neurosurgeons perform MVD using the latest microsurgical technique and intraoperative neuromonitoring.

Percutaneous Procedures

Performed as a short-stay procedure, a needle is passed through the cheek to access the trigeminal ganglion at the base of the skull. The nerve is then partially treated to reduce the abnormal pain signals responsible for trigeminal neuralgia.

• Percutaneous radiofrequency – controlled heat applied to selectively damage pain fibres.
• Percutaneous glycerol – glycerol injection causes chemical damage to the nerve.
• Percutaneous balloon compression – balloon inflation causes mechanical compression of the ganglion.

These procedures are effective and are a good option for older patients, those who are not well enough for open surgery, or those with MS-related trigeminal neuralgia. They are not as long-lasting as microvascular decompression (MVD) and carry a risk of facial numbness.

Stereotactic Radiosurgery (Gamma Knife)

A single focused dose of radiation is delivered to the trigeminal nerve. Pain relief is not immediate, and onset is typically over 1–3 months. It is effective in approximately 70–80% of patients. This option is well suited to patients who are not fit enough for surgery, or who prefer to avoid an operation.