gamma knife

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gamma Knife

a minimally invasive radiosurgical system used in the treatment of benign and malignant intracranial neoplasms and arteriovenous malformations.
See also: radiosurgery.

Gamma Knife is a registered trademark of Elekta Radiosurgery of Atlanta, Georgia. The system was developed in the late 1960s by Lars Leksell and Borge Larsson of Sweden. As a preliminary to use of the Gamma Knife, the lesion to be ablated is precisely located by imaging techniques such as MRI, CT, PET, and angiography. Beams of gamma rays from 200 cobalt-60 sources are then directed by a computer so that they converge on the lesion. A series of exposures are made during a period of about 1 hour. Lesions larger than about 3 cm cannot be treated. The mechanism is bulky and costly, but the procedure has shown a success rate of about 85% in the treatment of arteriovenous malformations and 50-95% percent for neoplasms. Besides avoiding the risks and complications of open surgery, the Gamma Knife permits treatment of lesions the location of which prohibits any attempt at surgical removal. In addition, patient discomfort is minimal and most patients remain in the hospital for only 1 night. Many return home, or even to work, on the day of treatment. The Gamma Knife has demonstrated limited usefulness in the treatment of other disorders, such as tumors of the eye and the pituitary gland, trigeminal neuralgia, epilepsy, parkinsonism, and other movement disorders.

Gamma Knife

A trademark for a radiologic nonsurgical device used in stereotactic radiosurgery.

gamma knife

an apparatus for precisely aimed intersecting beams of gamma rays that delivers radiation therapies as treatment for intracranial lesions, either tumors or vascular anomalies. It is used in stereotactic radiosurgery.

gamma knife

Radiation oncology An RT device that provides 201 stereotactically focused beams of γ radiation from 60Co that destroys intracranial targets; the GK and linear accelerators can be adapted to irradiate localized regions of the brain Indications AV malformations, meningiomas, acoustic neuromas, pituitary adenomas, craniopharyngiomas, 1º and 2º tumors

Gamma knife

A surgical tool that focuses beams of radiation at the head, which converge in the brain to form a lesion.
Mentioned in: Brain Tumor, Psychosurgery

Gam·ma Knife

(gamă nīf)
Minimally invasive radiosurgical system used to treat benign and malignant intracranial neoplasms and arteriovenous malformations. [Gamma Knife is a registered trademark of Elekta Radiosurgery of Atlanta, Georgia.]
References in periodicals archive ?
Gamma Knife Icon represents the sixth generation of the company's Leksell Gamma Knife system, a technology that has been in use worldwide and continually evolving since the 1960s.
Peng Li from China talking about Gamma Knife Radiosurgery for Cavernous hemangioma said that is a rare disease which represents 3% of all benign Cavernous stress tumors.
By indication type, the global Gamma Knife market is segmented into brain metastasis, cancer arteriovenous malformation (AVM), trigeminal neuralgia and others.
More than 30 patients have already undergone treatment using the Gamma Knife since it began operating as a state-wide referral service at the PAH in October.
Gamma Knife surgery presents fewer risks or complications than traditional open skull surgery.
If candidacy for Gamma Knife radiosurgery is determined, the nurse contacts the patient for a pretreatment visit.
What makes the Gamma Knife so unique is that it treats this condition with no incision, and without general anesthesia.
It is a very attractive alternative to conventional surgery," says Ernest Bates, a neurosurgeon and CEO of San Francisco-based American Shared Hospital Services, which sells the Gamma Knife in a joint venture with the only firm that manufactures the device, Sweden's Elekta AB.
On June 27, a 75-year-old male patient received frameless, mask-based radiosurgery on Centre Hospitalier Universitaire Vaudois's Leksell Gamma Knife Icon making him Switzerland's first to receive treatment on the country's first and only Icon system.
Swedish medical technology group Elekta AB said on Thursday (10 May) that it has received a first Portuguese order for its non-invasive radiosurgery system Leksell Gamma Knife Perfexion.
Called a Gamma Knife, it uses an array of powerful radiation beams to target brain tumors that a surgeon can't reach, doctors said.