A patient with trigeminal neuralgia (TN) experiences excruciating pain characterized as recurrent extreme burning or electric shock, usually triggered by routine activities like eating, talking, brushing the teeth or touching the face. The most common cause of TN is an artery compressing the trigeminal nerve as it enters the brain stem. Because TN only affects four in 100,000 people annually, it is unfamiliar to many physicians and is often misdiagnosed. Joshua Dowling, MD, Washington University neurosurgeon at Barnes-Jewish Hospital, sees patients from all over the Midwest for treatment of TN.
“Despite the rarity of the condition, I see 70 patients a year for surgery and many more for medical management. At Barnes-Jewish Hospital, we are fortunate to have the full range of treatments available, so it’s likely that one will be right for any given patient. Often physicians treating patients for TN may be reluctant to recommend surgery because they are concerned about the risks; however, there are low-risk options.”
Dowling stresses that the goal of treatment is for the patient to be pain-free with a minimum of side effects. He starts with medical therapy, usually prescribing anticonvulsants such as carbamazepine or gabapentin. Only when drugs don’t manage the pain or the side effects are too onerous will he consider one of the following surgical procedures:
- Microvascular decompression is a major intracranial procedure that does not generally result in facial numbness. “This procedure is effective 90 percent of the time, works immediately with a low complication rate and twothirds of the time is permanent. For a younger patient in good health, its longevity makes this a good choice,” says Dowling.
- Percutaneous radiofrequency rhizotomy or glycerol rhizotomy doesn’t involve brain surgery and is safer for high-risk patients. Both provide immediate relief but can wear off. Multiple sclerosis patients can develop recurrent TN because of changes in that disease, so percutaneous radiofrequency may be a better choice for them.
- Stereotactic radiosurgery with a Gamma Knife focuses multiple beams of radiation on a precise area of the nerve root to deliver a high dose of radiation deep into the head. It injures the nerve enough to treat the pain while limiting numbness. For most patients, this treatment is ultimately effective, but it can take from two weeks to two months for the pain to subside.
Some patients are afraid that numbing the trigeminal nerve will cause facial droop. Dowling says that droop is caused by injury to the facial nerve, not the trigeminal nerve. Dowling also notes that if the source of the pain is not from trigeminal neuralgia, surgery can potentially aggravate the condition