Brain stereotactic radiosurgery (Gamma knife). 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 up to a month. Brain stereotactic radiosurgery is successful in eliminating pain for the majority of people. If pain recurs, the procedure can be repeated. Facial numbness can be a side effect.
Other procedures may be used to treat trigeminal neuralgia, such as a rhizotomy. In a rhizotomy, your surgeon destroys nerve fibers to reduce pain, and this 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 at least some transient facial numbness.
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 briefly 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. Pain may return after three to four years.