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Although the drugs used for the management of trigeminal neuralgia (TN) pain are highly effective for many people, approximately 25% to 50% of TN patients eventually stop responding to these medications. For these patients, surgery may be considered as a viable and potentially effective treatment option.

In general, surgical procedures for trigeminal neuralgia can be classified as either non-destructive or destructive:

• Non-destructive procedures - treatment is intended to eliminate the underlying cause of the trigeminal neuralgia without causing injury or damage to the nerve. Microvascular decompression is the only type of non-destructive surgical procedure that can effectively be used to treat TN when the cause of the pain is due to vascular compression.

• Destructive procedures - treatment is intended to control the pain by destroying or damaging sections of the trigeminal nerve. Examples include:

  • percutanous rhizotomy (gangliolysis)
  • stereotactic radiosurgery (Gamma Knife)
  • retrogasserian neurotomy
  • peripheral neurectomy
  • trigeminal tractotomy

Non-Destructive Procedures

Microvascular decompression

Microvascular decompression (MVD) is considered to be the only non-destructive surgical procedure that effectively eliminates the underlying cause of trigeminal neuralgia when the condition is due to compression of the trigeminal nerve by blood vessels (vascular compression). Microvascular decompression is referred to as a "non-destructive" surgical procedure because, unlike the other surgical procedures outlined below, it does not involve causing an injury or damage to the nerve. The goal of MVD is to alleviate the pain of TN by eliminating the cause of the pain which, in many cases, is due to vascular compression of the trigeminal nerve.

Microvascular decompression surgery is performed by a neurosurgeon in a hospital setting under general anesthesia. It is important to choose a neurosurgeon who is experienced with this surgical procedure and specializes in the treatment of trigeminal neuralgia. After the patient has received general anesthesia, the surgeon will create a suboccipital craniectomy (surgical removal of a portion of the skull in the suboccipital region) to access and view the trigeminal nerve. Using a special operating microscope, the surgeon will decompress (eliminate the compression) the nerve. Veins that are compressing the nerve are coagulated and divided. Arteries that are pressing against the nerve are repositioned and a pad of Teflon cotton is placed between the artery and nerve to prevent the artery from sliding back and pressing against the nerve. After the surgery, patients usually spend about 3 days in the hospital recuperating. Immediate pain relief is experienced by about 90% of patients who undergo MVD surgery and about 70% of patients will achieve long-term pain relief. Complications of MVD are rare but may include:

• Facial numbness
• Facial weakness
• Hearing loss
• Cerebrospinal fluid (CSF) leakage
• Injury to the cerebellum (edema, contusion, or hematoma)

There have been some reports of pain recurring after 10-20 years but the reason is unclear since upon reoperation, new compression is rarely found.

Patients who have had less invasive surgeries to no avail are sometimes considered candidates for this surgery.

Destructive Procedures

Percutaneous Rhizotomy (Gangliolysis)

Unlike microvascular decompression (MVD) surgery which actually eliminates the vascular compression on the nerve that is often the cause of trigeminal neuralgia, a rhizotomy is a destructive surgical procedure that is intended to alleviate the pain associated with TN by destroying or damaging a section of the trigeminal nerve usually at the Gasserian ganglion or trigeminal nerve root. A rhizotomy is a percutaneous ("through the skin") procedure that can be performed on an outpatient basis either under local or brief general anesthesia and is less invasive than MVD surgery. In performing a percutaneous rhizotomy, the surgeon inserts a needle through the cheek into an opening at the base of the skull known as the foramen ovale to gain access to the Gasserian ganglion and trigeminal nerve root. Using one of three specific rhizotomy techniques described below, the surgeon will deliberately produce a controlled injury to the Gasserian ganglion and trigeminal nerve root in order to block the pain sensation associated with trigeminal neuralgia.