trigeminal neuralgia rf ablation
Trigeminal neuralgia treatment usually starts with medications, and some people don’t need any additional treatment. However, over time, some people with the condition may stop responding to medications, or they may experience unpleasant side effects
Trigeminal neuralgia (TN or TGN) is a chronic pain disorder that affects the trigeminal nerve. There are two main types: typical and atypical trigeminal neuralgia. The typical form results in episodes of severe, sudden, shock-like pain in one side of the face that lasts for seconds to a few minutes. Groups of these episodes can occur over a few hours. The atypical form results in a constant burning pain that is less severe. Episodes may be triggered by any touch to the face. Both forms may occur in the same person. It is one of the most painful conditions, and can result in depression.
The exact cause is unclear, but believed to involve loss of the myelin around the trigeminal nerve.This may occur due to compression from a blood vessel as the nerve exits the brain stem, multiple sclerosis, stroke, or trauma. Less common causes include a tumor or arteriovenous malformation. It is a type of nerve pain. Diagnosis is typically based on the symptoms, after ruling out other possible causes such as postherpetic neuralgia.
Treatment includes medication or surgery. The anticonvulsant carbamazepine or oxcarbazepine is usually the initial treatment, and is effective in about 80% of people. Other options include lamotrigine, baclofen, gabapentin, and pimozide. Amitriptyline may help with the pain, but opioids are not usually effective in the typical form. In those who do not improve or become resistant to other measures, a number of types of surgery may be tried.
If your condition is due to another cause, such as multiple sclerosis, your doctor will treat the underlying condition.
To treat trigeminal neuralgia, your doctor usually will prescribe medications to lessen or block the pain signals sent to your brain.
- Anticonvulsants. Doctors usually prescribe carbamazepine (Tegretol, Carbatrol, others) for trigeminal neuralgia, and it’s been shown to be effective in treating the condition. Other anticonvulsant drugs that may be used to treat trigeminal neuralgia include oxcarbazepine (Trileptal), lamotrigine (Lamictal) and phenytoin (Dilantin, Phenytek). Other drugs, including clonazepam (Klonopin) and gabapentin (Neurontin, Gralise, others), also may be used.If the anticonvulsant you’re using begins to lose effectiveness, your doctor may increase the dose or switch to another type. Side effects of anticonvulsants may include dizziness, confusion, drowsiness and nausea. Also, carbamazepine can trigger a serious drug reaction in some people, mainly those of Asian descent, so genetic testing may be recommended before you start carbamazepine.
- Antispasmodic agents. Muscle-relaxing agents such as baclofen (Gablofen, Lioresal) may be used alone or in combination with carbamazepine. Side effects may include confusion, nausea and drowsiness.
- Botox injections. Small studies have shown that onabotulinumtoxinA (Botox) injections may reduce pain from trigeminal neuralgia in people who are no longer helped by medications. However, more research needs to be done before this treatment is widely used for this condition.
The goal of trigeminal neuralgia surgery is to stop the blood vessel from compressing the trigeminal nerve or to damage the trigeminal nerve to keep it from malfunctioning. Damaging the nerve often causes temporary or permanent facial numbness, and with any of the surgical procedures, the pain can return months or years later.
Surgical options for trigeminal neuralgia include:
- Microvascular decompression. This procedure involves relocating or removing blood vessels that are in contact with the trigeminal root. During microvascular decompression, your doctor makes an incision behind the ear on the side of your pain. Then, through a small hole in your skull, your surgeon moves any arteries that are in contact with the trigeminal nerve away from the nerve, and places a pad between the nerve and the arteries.If a vein is compressing the nerve, your surgeon may remove it. Doctors also may cut part of the trigeminal nerve (neurectomy) during this procedure if arteries aren’t pressing on the nerve.Microvascular decompression can successfully eliminate or reduce pain most of the time, but pain can recur in some people. Microvascular decompression has some risks, including decreased hearing, facial weakness, facial numbness, a stroke or other complications. Most people who have this procedure have no facial numbness afterward.
- Gamma Knife radiosurgery. In this procedure, a surgeon directs a focused dose of radiation to the root of your trigeminal nerve. This procedure uses radiation to damage the trigeminal nerve and reduce or eliminate pain. Relief occurs gradually and may take several weeks.Gamma Knife radiosurgery is successful in eliminating pain for the majority of people. If pain recurs, the procedure can be repeated.
Other procedures may be used to treat trigeminal neuralgia, such as a rhizotomy. In a rhizotomy, your surgeon destroys nerve fibers, which causes some facial numbness. Types of rhizotomy include:
- Glycerol injection. During this procedure, your doctor inserts a needle through your face and into an opening in the base of your skull. Your doctor guides the needle into the trigeminal cistern, a small sac of spinal fluid that surrounds the trigeminal nerve ganglion — where the trigeminal nerve divides into three branches — and part of its root. Then, your doctor will inject a small amount of sterile glycerol, which damages the trigeminal nerve and blocks pain signals.This procedure often relieves pain. However, some people have a later recurrence of pain, and many experience facial numbness or tingling.
- Balloon compression. In balloon compression, your doctor inserts a hollow needle through your face and guides it to a part of your trigeminal nerve that goes through the base of your skull. Then, your doctor threads a thin, flexible tube (catheter) with a balloon on the end through the needle. Your doctor inflates the balloon with enough pressure to damage the trigeminal nerve and block pain signals.Balloon compression successfully controls pain in most people, at least for a period of time. Most people undergoing this procedure experience some facial numbness, and some experience temporary or permanent weakness of the muscles used to chew.
- Radiofrequency thermal lesioning
- This procedure selectively destroys nerve fibers associated with pain. While you’re sedated, your surgeon inserts a hollow needle through your face and guides it to a part of the trigeminal nerve that goes through an opening at the base of your skull.Once the needle is positioned, your surgeon will wake you from sedation. Your surgeon inserts an electrode through the needle and sends a mild electrical current through the tip of the electrode. You’ll be asked to indicate when and where you feel tingling.When your neurosurgeon locates the part of the nerve involved in your pain, you’re returned to sedation. Then the electrode is heated until it damages the nerve fibers, creating an area of injury (lesion). If your pain isn’t eliminated, your doctor may create additional lesions.Radiofrequency thermal lesioning usually results in some temporary facial numbness after the procedure.