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Psychosurgery involves severing or otherwise disabling areas of the brain to treat a personality disorder, behavior disorder, or other mental illness. Modern psychosurgical techniques target the pathways between the limbic system (the portion of the brain on the inner edge of the cerebral cortex) that is believed to regulate emotions, and the frontal cortex, where thought processes are seated.
Lobotomy is a psychosurgical procedure involving selective destruction of connective nerve fibers or tissue. It is performed on the frontal lobe of the brain and its purpose is to alleviate mental illness and chronic pain symptoms. The bilateral cingulotomy, a modern psychosurgical technique which has replaced the lobotomy, is performed to alleviate mental disorders such as major depression, bipolar disorder, or obsessive-compulsive disorder (OCD), which have not responded to psychotherapy, behavioral therapy, electroshock, or pharmacologic treatment. Bilateral cingulotomies are also performed to treat chronic pain in cancer patients.
Psychosurgery should be considered only after all other non-surgical psychiatric therapies have been fully explored. Much is still unknown about the biology of the brain and how psychosurgery affects brain function.
Psychosurgery, and lobotomy in particular, reached the height of use just after World War II. Between 1946 and 1949, the use of the lobotomy grew from 500 to 5,000 annual procedures in the United States. At that time, the procedure was viewed as a possible solution to the overcrowded and understaffed conditions in state-run mental hospitals and asylums. Known as prefrontal or transorbital lobotomy, depending on the surgical technique used and area of the brain targeted, these early operations were performed with surgical knives, electrodes, suction, or ice picks, to cut or sweep out portions of the frontal lobe.
Today's psychosurgical techniques are much more refined. Instead of going in "blind" to remove large sections on the frontal lobe, as in these early operations, neurosurgeons use a computer-based process called stereotactic magnetic resonance imaging to guide a small electrode to the limbic system (brain structures involved in autonomic or automatic body functions and some emotion and behavior). There an electrical current burns in a small lesion [usually 0.5 in (1.3 cm) in size]. In a bilateral cingulotomy, the cingulate gyrus, a small section of brain that connects the limbic region of the brain with the frontal lobes, is targeted. Another surgical technique uses a non-invasive tool known as a gamma knife to focus beams of radiation at the brain. A lesion forms at the spot where the beams converge in the brain.
Candidates for cingulotomies or other forms of psychosurgery undergo a rigorous screening process to ensure that all possible non-surgical psychiatric treatment options have been explored. Psychosurgery is only performed with the patient's informed consent.
Ongoing behavioral and medication therapy is often required in OCD patients who undergo cingulotomy. All psychosurgery patients should remain under a psychiatrist's care for follow-up evaluations and treatment.
As with any type of brain surgery, psychosurgery carries the risk of permanent brain damage, though the advent of non-invasive neurosurgical techniques, such as the gamma knife, has reduced the risk of brain damage significantly.
In a 1996 study at Massachusetts General Hospital, over one-third of patients undergoing cingulotomy demonstrated significant improvements after the surgery. And, in contrast to the bizarre behavior and personality changes reported with lobotomy patients in the 1940s and 1950s, modern psychosurgery patients have demonstrated little post-surgical losses of memory or other high level thought processes.
Massachusetts General Hospital. Functional and Stereotactic Neurosurgery Cingulotomy Unit. Fruit St., Boston, MA 02114. (617) 726-2000. 〈http://neurosurgery.mgh.harvard.edu/cingulot.htm〉.
National Alliance for the Mentally Ill (NAMI). Colonial Place Three, 2107 Wilson Blvd., Ste. 300, Arlington, VA 22201-3042. (800) 950-6264. http://www.nami.org.
National OCD Headquarters. P.O. Box 70, Milford, CT 06460. (203) 878-5669.
Gamma knife — A surgical tool that focuses beams of radiation at the head, which converge in the brain to form a lesion.
Lesion — Any discontinuity of tissue. Often a cut or wound.
Limbic system — A portion of the brain on the inner edge of the cerebral cortex that is thought to regulate emotions.
Psychosurgery — Brain surgery performed to alleviate chronic psychological conditions such as obsessive-compulsive disorder (OCD), depression, and bipolar disorder.
Stereotactic technique — A technique used by neurosurgeons to pinpoint locations within the brain. It employs computer imaging to create an external frame of reference.
brain surgery done to treat psychiatric disorders. adj., adj psychosur´gical.
The treatment of mental disorders by operation on the brain, for example, lobotomy.
n. pl. psychosurger·ies
Brain surgery used to treat severe, intractable mental or behavioral disorders.
psy′cho·sur′geon (-sûr′jən) n.
psy′cho·sur′gi·cal (-jĭ-kəl) adj.
psychosurgeryA general term for neurosurgery intended to alleviate psychiatric symptoms. The tools used in modern psychosurgery result in selective tract destruction and include radioactive 90Yt implants in the substantia innominata, cryoprobes, coagulation, proton beams and ultrasonic waves. Psychosurgery is not commonly performed, as it must be first established that a patient is unresponsive to all other therapies and that the condition is chronic (i.e., > 3 years duration).
Significant improvement is reported in 60% of carefully selected patients; in 3%, the symptoms worsen after the procedure. The measurable intelligence quotient may actually increase, due to an improved ability to concentrate and memorise, while distractibility is reduced to a minimum.
Psychosurgery was first performed in 1890 by G Burckhardt. Early psychosurgical procedures included topectomy (removal of pieces of cerebral cortex, weighing 20 g for pain to 50 g for fulminant schizophrenia). Other early procedures included lobectomy and leukotomy (popularised by W Freeman, which consisted of thrusting an icepick-like device through the eye socket and manipulating the handle to rupture myelinated tracts). The Freeman procedure’s popularity peaked in the late 1940s, its decline coinciding with the availability of the first effective psychoactive drugs.
Seen in 1 %, complications include infections, haemorrhage, and seizures.
psychosurgeryNeurosurgery Neurosurgery intended to alleviate psychiatric Sx, by selectively destroying neural tracts; psychosurgery includes radioactive 90Yt implants in the substantia innominata, cryoprobes, coagulation, proton beams and ultrasonic waves; psychosurgery is rarely performed, as it must be established that a Pt is unresponsive to all other therapies and that the condition is chronic–ie, > 3 yrs duration; significant improvement is reported in 60% of carefully selected Pts; in 3%, the Sx worsen after the procedure; the measurable IQ may ↑, given the ↑ ability to concentrate and memorize, while distraction is minimized Complications 1%; include infections, hemorrhage, seizures. Cf Psychic surgery.
The treatment of mental disorders by surgery on the brain (e.g., lobotomy).
psychosurgeryAny brain operation performed to relieve severe mental illness. Developments in drug therapy have reduced the need for psychosurgery, and the cruder forms, such as a prefrontal lobotomy, are now obsolete. More precise methods, employing stereotaxic surgery, are still sometimes used to relieve dangerous depression or anxiety or to treat disabling obsessive-compulsive disorder. Parts of the temporal lobe of the brain are sometimes removed to treat temporal lobe EPILEPSY.
Treatment of mental disorders by surgical operation on the brain, e.g., lobotomy.