A noninvasive medical procedure that fires beams of radiation into a nerve is just as effective as surgery in treating an excruciatingly painful facial disorder, according to a recent study. The neurosurgeon and his colleagues who conducted the study will discuss their findings at the 69th Annual Scientific Meeting of the American Association of Neurological Surgeons (AANS) on Wednesday, April 25.
of Neurological Surgeons (AANS)
Heather Monroe (firstname.lastname@example.org)
TORONTO (April 23, 2001)-- A noninvasive medical procedure that fires beams of radiation into a nerve is just as effective as surgery in treating an excruciatingly painful facial disorder, according to a recent study. The neurosurgeon and his colleagues who conducted the study will discuss their findings at the 69th Annual Scientific Meeting of the American Association of Neurological Surgeons (AANS) on Wednesday, April 25.
The study found that Gamma Knife radiosurgery relieves the pain of trigeminal neuralgia as effectively as traditional surgical treatments and is considerably safer. The study was led by Ronald F. Young, MD, a neurosurgeon from Seattle, Washington.
Trigeminal neuralgia is a disorder of the trigeminal nerve that causes episodes of stabbing pain around the lips, eyes, nose, jaw and other areas where the nerve travels. It occurs in three or four people per 100,000, most often in those over 50 and in more women than men.
Anticonvulsant drugs are commonly prescribed for the disorder, but they can cause serious side effects or be ineffective. Surgery for the disorder (usually a procedure called microvascular decompression) carries the risk of hemorrhage, infection, stroke, spinal fluid leak and numbness.
"We found that in more than 85 percent of patients the Gamma Knife radiosurgery was successful," said Dr. Young. "At the last follow-up, about 60 percent of patients were completely pain free and nearly 25 percent were pain free with a very small dose of medication."
Despite its name, Gamma Knife radiosurgery is not a knife and does not involve an incision or general anesthesia. The gamma knife is a machine that shoots 201 finely focused beams of radiation into the skull. Treatment can be as short as 45 minutes and patients feel no pain. They often go home the same day.
Developed 50 years ago by a neurosurgeon, the Gamma Knife is being applied to more disorders as researchers confirm its advantages over traditional surgery or intensive radiation therapy. The Gamma Knife is increasingly being used to treat tremors as well as brain tumors and AVMs.
The Gamma Knife uses a technique called stereotactic radiosurgery. "Stereos" is Greek for three-dimensional, and stereotactic radiosurgery involves making an image map of the brain, usually by an MRI or a CT (CAT) scan. The brain images are transferred to a computerized treatment planning system, which isolates the target area and allows the gamma rays to hit their mark.
Microvascular decompression surgery for trigeminal neuralgia attacks the cause of the disorder by decompressing the trigeminal nerve, while the Gamma Knife procedure treats the effect of the disorder. "Theoretically, surgery should be more effective but our study shows that radiosurgery produces the same results," said Dr. Young.
One drawback to Gamma Knife radiosurgery is that the pain may not disappear for several days or even months. Patients with particularly acute cases of trigeminal neuralgia may want to opt for surgery, said Dr. Young.
Dr. Young and his colleagues studied the outcomes of 435 patients who underwent Gamma Knife radiosurgery for trigeminal neuralgia following unsuccessful drug treatment and unsuccessful surgical treatment for 185 of them. The only side effect was transient facial numbness in 16 percent of patients.
The study also tracked 51 patients who needed another treatment because the first treatment failed or the pain later recurred. Eighty percent of these patients experienced successful pain relief.
The study is the largest and longest to date on Gamma Knife radiosurgery and trigeminal neuralgia. A previous study tracked about half as many patients with a median follow-up of two years, compared to the 4.2 years of Young's study.
The other authors of the study were Deane B. Jacques, MD, Rufus Mark, MD, Brian Copcutt, PhD, all of Los Angeles; and Francisco Li, MS, of Seattle.
Founded in 1931 as
the Harvey Cushing Society, the American Association of Neurological Surgeons
is a scientific and educational association with nearly 5,800 members worldwide.
The AANS is dedicated to advancing the specialty of neurological surgery
in order to provide the highest quality of neurosurgical care to the public.
All active members of the AANS are Board-certified by the American Board
of Neurological Surgery. Neurosurgery is the medical specialty concerned
with the prevention, diagnosis, treatment and rehabilitation of disorders
that affect the spine, brain, nervous system and peripheral nerves.
Media Representatives: If you would like to cover the meeting or interview a neurosurgeon -- either on-site or via telephone -- please contact the AANS Communications staff at 847/378-0517 prior to April 23 or call the Annual Meeting Press Room beginning Monday, April 23, at 416 /585-3878 (3879).