What is a trigeminal nerve injection?
A trigeminal nerve injection or block is an injection of a medication that aims to relieve the pain of trigeminal neuralgia, “shingles” and other types of facial pain. This targets the trigeminal nerves which is responsible for the sensation over your entire face including the eyes and the gums and cheeks.
How is a trigeminal nerve injection performed?
A sedative will be given so that you are calm and relaxed. In some cases, the sedation given may make your go into a light sleep. You will lie down on your back and your face will be cleaned with an anti-septic solution. A local anaesthetic solution will be given over the skin of the face. A thin needle will be inserted under X-ray guidance to the target site and the solution of local anaesthetic and steroid will be given.
How effective is a trigeminal nerve injection?
There is usually immediate pain relief, but the pain may recur after several hours when the local anaesthetic wears off. After a few days, the steroid effect kicks in and the pain relief lasts for a longer duration. How long this injection actually lasts will differ from patient to patient with some people requiring a series of injections to work. If the duration or the degree of the pain relief is not sufficient, we may proceed to do a radiofrequency treatment of the trigeminal nerve.
What is radiofrequency treatment of the trigeminal nerve and how does this work?
Radiofrequency treatment of the trigeminal nerve involves placement of a specialized radiofrequency needle at the trigeminal nerve. A current is then passed to create a radiofrequency field that either coagulates the nerve or modulates it, depending on the settings. This allows for longer lasting and better quality pain relief.
What are the risks associated with the procedures?
The risk of the procedures are very low. There may be brusing, swelling and soreness at the site of injection. It is uncommon to have more serious complications such as infection, bleeding and nerve damage. Other side effects that may be temporary usually subsides after several hours include difficulty speaking, chewing, swallowing and numbness.
Radiofrequency procedures that aim to destroy the trigeminal nerve may result in altered sensation over the face that might be unpleasant. There may be pain in an area of numbness, weakness of chewing, and rarely eye involvement with loss of the protective blinking reflex. Pulsed radiofrequency (PRF) is a non-destructive method of treating trigeminal neuralgia that avoids the above mentioned complications.
What should you do after the procedure to treat trigeminal neuralgia?
You should rest and avoid driving or exercising for the first 24 hours. Care should be taken during eating and drinking until it is clear that there are no temporary swallowing difficulties to avoid choking. There may be a flare of increased pain after the first few hours which should usually subside after a few days.