Neurosurgery or neurological surgery, known in common parlance as brain surgery, is the medical specialty concerned with the surgical treatment of disorders which affect any portion of the nervous system including the brain, spinal cord and peripheral nervous system.
Radiation therapy or radiotherapy, often abbreviated RT, RTx, or XRT, is a treatment using ionizing radiation, generally provided as part of cancer therapy to either kill or control the growth of malignant cells. It is normally delivered by a linear particle accelerator. Radiation therapy may be curative in a number of types of cancer if they are localized to one area of the body, and have not spread to other parts. It may also be used as part of adjuvant therapy, to prevent tumor recurrence after surgery to remove a primary malignant tumor. Radiation therapy is synergistic with chemotherapy, and has been used before, during, and after chemotherapy in susceptible cancers. The subspecialty of oncology concerned with radiotherapy is called radiation oncology. A physician who practices in this subspecialty is a radiation oncologist.
External beam radiation therapy (EBRT) is a compound word that refers to the use of a collimated beam of ionizing radiation from outside the body to treat a disease.
An isocentric technique is where all beams used in a radiation treatment have a common focus point, a.k.a. the isocenter. Isocentric techniques require less patient repositioning as multiple field arrangements can be delivered with gantry and collimator movements, reducing treatment times.
A vestibular schwannoma (VS), also called acoustic neuroma, is a benign tumor that develops on the vestibulocochlear nerve that passes from the inner ear to the brain. The tumor originates when Schwann cells that form the insulating myelin sheath on the nerve malfunction. Normally, Schwann cells function beneficially to protect the nerves which transmit balance and sound information to the brain. However, sometimes a mutation in the tumor suppressor gene, NF2, located on chromosome 22, results in abnormal production of the cell protein named Merlin, and Schwann cells multiply to form a tumor. The tumor originates mostly on the vestibular division of the nerve rather than the cochlear division, but hearing as well as balance will be affected as the tumor enlarges.
Lars Leksell (1907–1986) was a Swedish physician and Professor of Neurosurgery at the Karolinska Institute in Stockholm, Sweden. He was the inventor of radiosurgery.
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, it is usually used to treat cancer. Radiosurgery was originally defined by the Swedish neurosurgeon Lars Leksell as "a single high dose fraction of radiation, stereotactically directed to an intracranial region of interest".
Stereotactic surgery is a minimally invasive form of surgical intervention that makes use of a three-dimensional coordinate system to locate small targets inside the body and to perform on them some action such as ablation, biopsy, lesion, injection, stimulation, implantation, radiosurgery (SRS), etc.
Varian Medical Systems is an American radiation oncology treatments and software maker based in Palo Alto, California. Their medical devices include linear accelerators (LINACs) and software for treating cancer and other medical conditions with radiotherapy, radiosurgery, proton therapy, and brachytherapy. The company supplies software for managing cancer clinics, radiotherapy centers, and medical oncology practices. Varian Medical Systems employs more than 7,100 people at manufacturing sites in North America, Europe, and China and approximately 70 sites globally.
John R. Adler is an American neurosurgeon.
Tomotherapy is a type of radiation therapy treatment machine. In tomotherapy a thin radiation beam is modulated as it rotates around the patient, while they are moved through the bore of the machine. The name comes from the use of a strip-shaped beam, so that only one “slice” of the target is exposed at any one time by the radiation. The external appearance of the system and movement of the radiation source and patient can be considered analogous to a CT scanner, which uses lower doses of radiation for imaging. Like a conventional machine used for X-ray external beam radiotherapy, a linear accelerator generates the radiation beam, but the external appearance of the machine, the patient positioning, and treatment delivery is different. Conventional linacs do not work on a slice-by-slice basis but typically have a large area beam which can also be resized and modulated.
Image-guided radiation therapy is the process of frequent imaging, during a course of radiation treatment, used to direct the treatment, position the patient, and compare to the pre-therapy imaging from the treatment plan. Immediately prior to, or during, a treatment fraction, the patient is localized in the treatment room in the same position as planned from the reference imaging dataset. An example of IGRT would include comparison of a cone beam computed tomography (CBCT) dataset, acquired on the treatment machine, with the computed tomography (CT) dataset from planning. IGRT would also include matching planar kilovoltage (kV) radiographs or megavoltage (MV) images with digital reconstructed radiographs (DRRs) from the planning CT.
Cobalt therapy is the medical use of gamma rays from the radioisotope cobalt-60 to treat conditions such as cancer. Beginning in the 1950s, cobalt-60 was widely used in external beam radiotherapy (teletherapy) machines, which produced a beam of gamma rays which was directed into the patient's body to kill tumor tissue. Because these "cobalt machines" were expensive and required specialist support, they were often housed in cobalt units. Cobalt therapy was a revolutionary advance in radiotherapy in the post-World War II period but is now being replaced by other technologies such as linear accelerators.
The CyberKnife System is a radiation therapy device manufactured by Accuray Incorporated. The system is used to deliver radiosurgery for the treatment of benign tumors, malignant tumors and other medical conditions.
Reno CyberKnife is a cancer treatment center in Reno, Nevada specializing in stereotactic radiosurgery. The center is a service of Saint Mary’s Regional Medical Center and is also a part of Saint Mary’s Brain Tumor Center. Reno CyberKnife is the only provider of CyberKnife technology in northern Nevada and frequently treats prostate and lung cancers and brain tumors.
The N-localizer is a device that enables guidance of stereotactic surgery or radiosurgery using tomographic images that are obtained via computed tomography (CT), magnetic resonance imaging (MRI), or positron emission tomography (PET). The N-localizer comprises a diagonal rod that spans two vertical rods to form an N-shape and permits calculation of the point where a tomographic image plane intersects the diagonal rod. Attaching three N-localizers to a stereotactic instrument allows calculation of three points where a tomographic image plane intersects three diagonal rods. These points determine the spatial orientation of the tomographic image plane relative to the stereotactic frame.
Jefferson Hospital for Neuroscience is a hospital in Center City Philadelphia, affiliated with Thomas Jefferson University and Thomas Jefferson University Hospital in Philadelphia. The hospital focuses on treating brain-related diseases and disorders. It is the only hospital of its kind in the Philadelphia area.
Robert Wheeler Rand, was an American neurosurgeon, inventor, and Professor of Neurosurgery in the Department of Neurosurgery at the University of California Los Angeles (UCLA) from 1953 to 1989.
Jay Steven Loeffler was an American physician at Massachusetts General Hospital where he served as Chair of the Department of Radiation Oncology since 2000. He was the Herman and Joan Suit Professor of Radiation Oncology and Professor of Neurosurgery at Harvard Medical School.
Laurent Leksell is a Swedish PhD Economics, international business leader and entrepreneur.
