Radiosurgery is indicated primarily for the therapy of tumors, vascular lesions and functional disorders. Significant clinical judgment must be used with this technique and considerations must include lesion type, pathology if available, size, location and age and general health of the patient.
What are the uses of radiosurgery?
Radiosurgery is indicated primarily for the therapy of tumors, vascular lesions and functional disorders. Significant clinical judgment must be used with this technique and considerations must include lesion type, pathology if available, size, location and age and general health of the patient.
What conditions can stereotactic radiosurgery treat?
May 12, 2016 · March 18th, 2021. Gamma Knife Radiosurgery is a precise form of radiation therapy used in the treatment of tumors and other disorders in the brain. In the procedure, specialized equipment delivers nearly 200 beams of gamma rays to a target. Consequently, the abnormality receives an intense, highly focused dose of radiation with only minimal damage to …
What is body radiosurgery?
Gamma knife has been the treatment of choice for various brain tumors and functional disorders. Current gamma knife radiosurgery is planned in a 'ball-packing' approach and delivered in a 'step-and-shoot' manner, i.e. it aims to 'pack' the different sized spherical high-dose volumes (called 'shots') into a tumor volume.
What are the indications for radiosurgery?
Radiosurgery is used to treat acoustic neuroma. This procedure uses x-ray beams to destroy the growth. Passages in the inner ear associated with maintaining equilibrium are the:
What is radiosurgery performed by?
Radiosurgery is performed by a multidisciplinary team of neurosurgeons, radiation oncologists and medical physicists to operate and maintain highly sophisticated, highly precise and complex instruments, including medical linear accelerators, the Gamma Knife unit and the Cyberknife unit. The highly precise irradiation of targets within the brain and spine is planned using information from medical images that are obtained via computed tomography, magnetic resonance imaging, and angiography .
What is the principle of radiosurgery?
The fundamental principle of radiosurgery is that of selective ionization of tissue, by means of high-energy beams of radiation. Ionization is the production of ions and free radicals which are damaging to the cells. These ions and radicals, which may be formed from the water in the cell or biological materials, can produce irreparable damage to DNA, proteins, and lipids, resulting in the cell's death. Thus, biological inactivation is carried out in a volume of tissue to be treated, with a precise destructive effect. The radiation dose is usually measured in grays (one gray (Gy) is the absorption of one joule of energy per kilogram of mass). A unit that attempts to take into account both the different organs that are irradiated and the type of radiation is the sievert, a unit that describes both the amount of energy deposited and the biological effectiveness.
How does a linear accelerator work?
A linear accelerator (linac) produces x-rays from the impact of accelerated electrons striking a high z target (usually tungsten). A Linac therefore can generate x-rays of any energy, though usually 6 MV photons are used. With a Linac the gantry moves in space to change the delivery angle. Linear accelerator equipment can also move the patient lying on the treatment couch to change the delivery point. These treatments involve using a stereotactic frame to restrict the patient's movement. The Novalis Shaped Beam Radiosurgery system and Tx Radiosurgery platform, from Brainlab, implement a frameless, non-invasive technique with X-ray imaging that has proven to be both comfortable for the patient and accurate. The Trilogy from Varian, or CyberKnife from Accuray, can also be used with non-invasive immobilization devices coupled with real-time imaging to detect any patient motion during a treatment.
What are the technological advances in radiosurgery?
Technological improvements in medical imaging and computing have led to increased clinical adoption of stereotactic radiosurgery and have broadened its scope in the 21st century. The localization accuracy and precision that are implicit in the word "stereotactic" remain of utmost importance for radiosurgical interventions and are significantly improved via image-guidance technologies such as the N-localizer and Sturm-Pastyr localizer that were originally developed for stereotactic surgery .
What is the name of the procedure that uses ionizing radiation?
1423298. [ edit on Wikidata] Radiosurgery is surgery using radiation, that is, the destruction of precisely selected areas of tissue using ionizing radiation rather than excision with a blade. Like other forms of radiation therapy (also called radiotherapy), it is usually used to treat cancer.
When was stereotactic radiosurgery invented?
Stereotactic radiosurgery was first developed in 1949 by the Swedish neurosurgeon Lars Leksell to treat small targets in the brain that were not amenable to conventional surgery. The initial stereotactic instrument he conceived used probes and electrodes. The first attempt to supplant the electrodes with radiation was made in the early fifties, with x-rays. The principle of this instrument was to hit the intra-cranial target with narrow beams of radiation from multiple directions. The beam paths converge in the target volume, delivering a lethal cumulative dose of radiation there, while limiting the dose to the adjacent healthy tissue. Ten years later significant progress had been made, due in considerable measure to the contribution of the physicists Kurt Liden and Börje Larsson. At this time, stereotactic proton beams had replaced the x-rays. The heavy particle beam presented as an excellent replacement for the surgical knife, but the synchrocyclotron was too clumsy. Leksell proceeded to develop a practical, compact, precise and simple tool which could be handled by the surgeon himself. In 1968 this resulted in the Gamma Knife, which was installed at the Karolinska Institute and consisted of several cobalt-60 radioactive sources placed in a kind of helmet with central channels for irradiation with gamma rays. This prototype was designed to produce slit-like radiation lesions for functional neurosurgical procedures to treat pain, movement disorders, or behavioral disorders that did not respond to conventional treatment. The success of this first unit led to the construction of a second device, containing 179 cobalt-60 sources. This second Gamma Knife unit was designed to produce spherical lesions to treat brain tumors and intracranial arteriovenous malformations (AVMs). Additional units were installed in the 1980s all with 201 cobalt-60 sources.
How are protons used in radiology?
Protons are extracted from proton donor materials by a medical synchrotron or cyclotron, and accelerated in successive transits through a circular, evacuated conduit or cavity, using powerful magnets to shape their path, until they reach the energy required to just traverse a human body, usually about 200 MeV. They are then released toward the region to be treated in the patient's body, the irradiation target. In some machines, which deliver protons of only a specific energy, a custom mask made of plastic is interposed between the beam source and the patient to adjust the beam energy to provide the appropriate degree of penetration. The phenomenon of the Bragg peak of ejected protons gives proton therapy advantages over other forms of radiation, since most of the proton's energy is deposited within a limited distance, so tissue beyond this range (and to some extent also tissue inside this range) is spared from the effects of radiation. This property of protons, which has been called the " depth charge effect" by analogy to the explosive weapons used in anti-submarine warfare, allows for conformal dose distributions to be created around even very irregularly shaped targets, and for higher doses to targets surrounded or backstopped by radiation-sensitive structures such as the optic chiasm or brainstem. The development of "intensity modulated" techniques allowed similar conformities to be attained using linear accelerator radiosurgery.
What type of radiation is used in radiosurgery?
Doctors use three types of technology to deliver radiation during stereotactic radiosurgery in the brain and other parts of the body: Linear accelerator (LINAC) machines use X-rays (photons) to treat cancerous and noncancerous abnormalities in the brain and other parts of the body. LINAC machines are also known by the brand name ...
How does stereotactic radiosurgery work?
Like other forms of radiation, stereotactic radiosurgery works by damaging the DNA of the targeted cells. The affected cells then lose the ability to reproduce, which causes tumors to shrink. Stereotactic radiosurgery of the brain and spine is typically completed in a single session. Body radiosurgery is used to treat lung, liver, ...
What is the treatment for trigeminal neuralgia?
Stereotactic radiosurgery treatment for trigeminal neuralgia targets the nerve root to disrupt these pain signals. Acoustic neuroma. An acoustic neuroma (vestibular schwannoma), is a noncancerous tumor that develops along the main balance and hearing nerve leading from your inner ear to your brain.
What is the difference between AVM and stereotactic radiosurgery?
AVM s may disrupt the normal flow of blood and lead to bleeding (hemorrhage) or stroke. Stereotactic radiosurgery destroys the AVM and causes the affected blood vessels to close off over time.
What is proton beam therapy?
Proton beam therapy (charged particle radiosurgery) is the newest type of stereotactic radiosurgery and is available in only a few research centers in the U.S, although the number of centers offering proton beam therapy has greatly increased in the last few years.
What is the term for radiotherapy of the brain?
When doctors use stereotactic radiosurgery to treat tumors in areas of the body other than the brain, it's sometimes called stereotactic body radiotherapy (SBRT) or stereotactic ablative radiotherapy (SABR). Doctors use three types of technology to deliver radiation during stereotactic radiosurgery in the brain and other parts of the body:
How many sessions of SRS?
These machines can perform stereotactic radiosurgery (SRS) in a single session or over three to five sessions for larger tumors, which is called fractionated stereotactic radiotherapy. Gamma Knife machines use 192 or 201 small beams of gamma rays to target and treat cancerous and noncancerous brain abnormalities.
Overview
- Stereotactic radiosurgery (SRS) uses many precisely focused radiation beams to treat tumors and other problems in the brain, neck, lungs, liver, spine and other parts of the body. It is not surgery in the traditional sense because there's no incision. Instead, stereotactic radiosurgery uses 3D imaging to target high doses of radiation to the affected area with minimal impact on the surrou…
Why It's Done
- Around 50 years ago, stereotactic radiosurgery was pioneered as a less invasive and safer alternative to standard brain surgery (neurosurgery), which requires incisions in the skin, skull, and membranes surrounding the brain and brain tissue. Since then, the use of stereotactic radiosurgery has expanded widely to treat a variety of neurological and other conditions, includi…
Risks
- Stereotactic radiosurgery doesn't involve surgical incisions, so it's generally less risky than traditional surgery. In traditional surgery, you may have risks of complications with anesthesia, bleeding and infection. Early complications or side effectsare usually temporary. They may include: 1. Fatigue.Tiredness and fatigue may occur for the first few weeks after stereotactic rad…
How You Prepare
- Preparation for stereotactic radiosurgery and stereotactic body radiotherapy may vary depending on the condition and body area being treated but usually involves the following steps:
What You Can Expect
- Stereotactic radiosurgery is usually an outpatient procedure, but the entire process will take most of a day. You may be advised to have a family member or friend who can be with you during the day and who can take you home. You may have a tube that delivers fluids to your blood stream (intravenous, or IV, line) to keep you hydrated during the day if you are not allowed to eat or drin…
Results
- The treatment effect of stereotactic radiosurgery occurs gradually, depending on the condition being treated: 1. Benign tumors (including vestibular schwannoma).Following stereotactic radiosurgery, the tumor may shrink over a period of 18 months to two years, but the main goal of treatment for benign tumors is to prevent any future tumor growth. 2. Malignant tumors.Cancero…
Clinical Trials
- Explore Mayo Clinic studiesof tests and procedures to help prevent, detect, treat or manage conditions.