- Gamma knife
Gamma Knife® (or Leksell Gamma Knife®) is a device used to treat
brain tumors with a high dose ofradiation therapy in one day. The device was invented byLars Leksell , a Swedish neurosurgeon, in 1967 at theKarolinska Institute inSweden .Gamma Knife® device contains 201
cobalt-60 sources of approximately 30curie s (1.1 TBq) each, placed in a circular array in a heavily shielded assembly. The device aims gamma radiation through a target point in the patient's brain. The patient wears a specialized helmet that is surgically fixed to their skull so that the brain tumor remains stationary at target point of the gamma rays. An ablative dose of radiation is thereby sent through the tumor in one treatment session, while surrounding brain tissues are relatively spared.Uses
Radiosurgery uses high doses ofradiation to eradicatecancer cells and shrinktumor s, delivered precisely to avoid damaging healthy brain tissue. Leksell Gamma Knife® radiosurgery is able to accurately focus many beams of high-intensity radiation to converge on one or more tumors. Each individual beam is relatively low energy, so the radiation has little effect on intervening brain tissue.Efficiency
Gamma Knife® radiosurgery has proved effective for patients with
benign ormalignant brain tumors, vascular malformations such as anarteriovenous malformation (AVM),pain or other functional problems. [cite journal |author=Régis J, Bartolomei F, Hayashi M, Chauvel P |title=What role for radiosurgery in mesial temporal lobe epilepsy |journal=Zentralbl. Neurochir. |volume=63 |issue=3 |pages=101–5 |year=2002 |pmid=12457334 |doi=10.1055/s-2002-35824 |url=] [cite journal |author=Kwon Y, Whang CJ |title=Stereotactic Gamma Knife radiosurgery for the treatment of dystonia |journal=Stereotact Funct Neurosurg |volume=64 Suppl 1 |issue= |pages=222–7 |year=1995 |pmid=8584831 |doi= |url=] [cite journal |author=Donnet A, Valade D, Régis J |title=Gamma knife treatment for refractory cluster headache: prospective open trial |journal=J. Neurol. Neurosurg. Psychiatr. |volume=76 |issue=2 |pages=218–21 |year=2005 |month=February |pmid=15654036 |pmc=1739520 |doi=10.1136/jnnp.2004.041202 |url=] [cite journal |author=Herman JM, Petit JH, Amin P, Kwok Y, Dutta PR, Chin LS |title=Repeat gamma knife radiosurgery for refractory or recurrent trigeminal neuralgia: treatment outcomes and quality-of-life assessment |journal=Int. J. Radiat. Oncol. Biol. Phys. |volume=59 |issue=1 |pages=112–6 |year=2004 |month=May |pmid=15093906 |doi=10.1016/j.ijrobp.2003.10.041 |url=] The procedure is less invasive than alternative surgeries such as open surgery. For treatment oftrigeminal neuralgia the procedure may be used repeatedly on patients.Ultimately, consideration for gamma knife radiosurgery treatment is contingent upon the patient's diagnosis,
medical history and the case's overall severity upon consultation. In some instances, radiation oncologists will consider treatment for patients with metastatic disease, the elderly and whose life span will not exceed fifteen years, as well as those with inoperablelesion s.The risks of Gamma Knife®
radiosurgery treatment are very small [cite journal |author=Chin LS, Lazio BE, Biggins T, Amin P |title=Acute complications following gamma knife radiosurgery are rare |journal=Surg Neurol |volume=53 |issue=5 |pages=498–502; discussion 502 |year=2000 |month=May |pmid=10874151 |doi= |url=http://linkinghub.elsevier.com/retrieve/pii/S0090-3019(00)00219-6] and complications are related to the condition being treated. [cite journal |author=Stafford SL, Pollock BE, Foote RL, "et al" |title=Meningioma radiosurgery: tumor control, outcomes, and complications among 190 consecutive patients |journal=Neurosurgery |volume=49 |issue=5 |pages=1029–37; discussion 1037–8 |year=2001 |month=November |pmid=11846894 |doi= |url=http://meta.wkhealth.com/pt/pt-core/template-journal/lwwgateway/media/landingpage.htm?issn=0148-396X&volume=49&issue=5&spage=1029] [cite journal |author=Cho DY, Tsao M, Lee WY, Chang CS |title=Socioeconomic costs of open surgery and gamma knife radiosurgery for benign cranial base tumors |journal=Neurosurgery |volume=58 |issue=5 |pages=866–73; discussion 866–73 |year=2006 |month=May |pmid=16639320 |doi=10.1227/01.NEU.0000209892.42585.9B |url=] The complication rate is increased when the method is used to treat conditions which are life threatening in the short term.ee also
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Minimally invasive procedure
*Radiation therapy
*Stereotactic surgery Gallery
Footnotes
References
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*cite journal |author=Rowe J, Grainger A, Walton L, Silcocks P, Radatz M, Kemeny A |title=Risk of malignancy after gamma knife stereotactic radiosurgery |journal=Neurosurgery |volume=60 |issue=1 |pages=60–5; discussion 65–6 |year=2007 |month=January |pmid=17228253 |doi=10.1227/01.NEU.0000255492.34063.32 |url=
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*External links
* [http://www.healthsystem.virginia.edu/internet/neurosurgery/gammaknifeinfo.cfm Gamma Knife History from the University of Virginia]
* [http://www.midmichigan.org/contentstore/gamma_cutaway_with%20labels_and_logo.pdf Cross-sectional view of Gamma Knife (Model C)]
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