 |
 |
Brain Device Offers Hope For Some Mental Disorders By Carey Goldberg, Globe Staff The Boston Globe, August 4, 2004 With its infamous history of crude ''icepick" lobotomies, psychiatric surgery has been widely shunned for decades. Now, it appears poised to make a careful comeback using a far gentler technology: a pacemaker for the brain that, once implanted, can be adjusted or turned off. Researchers at Butler Hospital in Providence are completing the largest study to date of the ''deep brain stimulation" device's potential to alleviate mental illness, involving 10 patients with severe, intractable obsessive compulsive disorder. The doctors say it looks promising, and they are beginning to test the device as a last resort for chronic depression. The brain stimulators, though widely used for Parkinson's disease, are still highly experimental for psychiatric disorders: Only a couple of dozen patients have received them worldwide. But they are generating high excitement among neurosurgeons, along with an equally acute sense of caution. ''Deep brain stimulation has and will revolutionize functional neurosurgery in the next decade," said Dr. G. Rees Cosgrove, a neurosurgeon at Massachusetts General Hospital, which is seeking to take part in the depression study. However, he said, surgeons must be supremely careful to ''avoid re-creating some of the mistakes of the past. This ''is a historical threshold," Cosgrove said. ''It needs to be done well and properly and be above reproach, or we'll never have another opportunity." The electrodes that deliver the stimulation are embedded in precise locations in the brain during an operation that lasts several hours. They are connected by wires to a pair of battery-powered pulse generators, each about 2 inches square, implanted in the patient's chest. It remains unclear why, exactly, the pulses work, but they appear to block or jam bad signals that travel through malfunctioning circuits in the brain. Patients generally cannot feel the pulses of high-frequency energy. The deep-brain stimulators have gained powerful momentum from their success in reducing symptoms in patients with Parkinson's disease. About 25,000 of the so- called Activa systems have been implanted worldwide since 1996, mainly in Parkinson's patients, according to Medtronic Inc. of Minneapolis, the only company that makes and sells them in the United States. The implants do not cure Parkinson's patients, but many people report major improvements that last for years. The downside: Between 1 percent and 5 percent of patients have experienced serious complications such as bleeding or seizures, and infections have arisen in from 2 percent to 25 percent of cases. Between 5 percent and 15 percent have had problems with the hardware that required repair. As the procedure has become more popular and familiar, neurosurgeons have begun trying it on a range of other illnesses, including epilepsy, in which the treatment of last resort had traditionally been ablative surgery: cutting or burning a lesion, or hole, in part of the brain. In tiny numbers, psychiatric patients have undergone sophisticated ablative psychosurgery in recent years, and because the surgery often helped, researchers reasoned that deep brain stimulation could bring similar results. Thus far, researchers report, the stimulation appears to work about as well in psychiatric patients as the ablative techniques. Those ablative operations have brought significantly reduced symptoms for 25 percent to 45 percent of psychiatric patients in which everything else had failed, Cosgrove said. Deep brain stimulation probably ''will recapitulate the whole history of ablative surgery in psychiatry, which fell into disrepute," said Dr. Daniel Tarsy, chief of the movement disorders center at Beth Israel Deaconess Medical Center, who has extensive experience with the stimulators. That disrepute stems from the mid-20th-century heyday of the lobotomy. Tens of thousands of mentally ill people underwent lobotomies, often without their consent, as illustrated by Jack Nicholson's character, R.P. McMurphy, in the movie ''One Flew Over The Cuckoo's Nest," based on the novel by Ken Kesey. The procedure's best-known proponent, Dr. Walter Freeman, traveled the country from state hospital to state hospital, lobotomizing patients by inserting an icepick- like instrument up through the socket of the eye, wiggling it around in the frontal lobes of the brain. The procedure began to lose favor only when effective psychiatric drugs began to appear in the mid-1950s, said Elliot S. Valenstein, author of ''Great and Desperate Cures," a history of psychosurgery. Valenstein, an emeritus professor at the University of Michigan, warned that the danger for abuse of a surgical procedure still exists, ''when you get the right combination of a strong need, plus no alternative, and some prestigious people pushing it, and the press talking about it being a breakthrough." It is a different era, however. In the studies at Butler Hospital, patients are protected by several levels of safeguards: an independent review board that includes community members and bioethicists; a prolonged process to make sure patients fully understand and agree to the procedure; and a ''consent monitor," a retired hospital chaplain who acts as a patient advocate. Dr. Benjamin Greenberg, the lead researcher and a Brown University associate professor of psychiatry, said that great care is also taken to ensure that patients have been correctly diagnosed and that they have exhausted all other possible treatments. In the depression study, that list must include electroshock treatments. The studies generally reject eight patients for every one they accept, he said, and patients must be referred by a psychiatrist. Psychosurgery using deep brain stimulation is expected to remain strictly a topic of research for the next several years before it could become clinically available at specialized centers, Greenberg said. Much remains to be perfected, including the brain locations for the electrodes and the settings of the stimulators. And ultimately only about 4,000 patients a year nationwide with obsessive compulsive disorder, and perhaps more with depression, would be good candidates for such last-ditch surgery, he estimated. Greenberg said he could not connect a reporter with a patient who has undergone the surgery; media contact can be difficult for them, he said. But in general, for the risk of surgery to be worthwhile, the patients must be severely disabled and in great suffering, he said. One patient operated on by Butler researchers endured obsessive thoughts and compulsive behaviors 14 to 16 hours a day, often waking at 4:30 in the morning to begin rituals of double-checking, arranging, counting, and rearranging things, Greenberg said. At one point, the patient withdrew $100 from a cash machine, then could not remember where $5 of it had gone, pulled over to the side of the road, and spent five hours trying to recall. The stimulator surgery holds appeal for patients in desperate need of better therapies. But, said Dr. Ken Duckworth, medical director for the National Alliance for the Mentally Ill, ''Nobody calls an election with 2 percent of the returns in." Better treatments are badly needed, he said, but so are better data on whether the stimulators are safe and effective. Medtronic, the company that makes the brain stimulator system, is ''cautious but very interested" in its potential for psychiatric disorders, said spokeswoman Kathleen Janasz. It is not sponsoring the initial clinical trials, she said, though Greenberg said it was helping to pay for them. Hundreds of surgeons are now capable of implanting the stimulator system, because of their experience with Parkinson's patients, and many have expressed interest in trying it. Dr. Alim Louis Benabid, the French neurosurgeon considered the father of deep brain stimulation for Parkinson's disease, said the stimulators hold great potential for transforming basic brain research into treatments. ''But," he wrote in an e-mail, ''I fear that this would become a medical (and worse, a surgical) market, which would push doctors as well as companies to overpractice." The stimulators, he said, ''may prove to be a wonderful new tool, or on the contrary a temptation for unjustified malpractice." Carey Goldberg is reachable at [log in to unmask] SOURCE: Boston Globe, Aug 4, 2004 http://tinyurl.com/59bpm * * * ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn