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Lars Leksell
Lars Leksell (24 November 1907 – 12 January 1986) was a Swedish physician and professor of Neurosurgery at the Karolinska Institute in Stockholm, Sweden. He was the inventor of radiosurgery. Life and career Lars Leksell was born in Fässberg Parish, Sweden on 24 November 1907. He completed medical studies at the Karolinska Institute and began his neurosurgical training in 1935 under Herbert Olivecrona. Development of electronystagmography and his thesis on muscular control and gamma motor neurons were his early scientific achievements. In 1949, he developed his arc centered stereotactic frame based on A polar coordinate system. In 1951, using the Uppsala University cyclotron, Leksell and the physicist and radiobiologist Borje Larsson (radiobiologist), Borje Larsson, developed the concept of radiosurgery. Leksell and Larsson first employed proton beams coming from several directions into a small area into the brain, in experiments in animals and in the first treatments of human pa ...
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Cyclotron
A cyclotron is a type of particle accelerator invented by Ernest Lawrence in 1929–1930 at the University of California, Berkeley, and patented in 1932. Lawrence, Ernest O. ''Method and apparatus for the acceleration of ions'', filed: January 26, 1932, granted: February 20, 1934 A cyclotron accelerates charged particles outwards from the center of a flat cylindrical vacuum chamber along a spiral path. The particles are held to a spiral trajectory by a static magnetic field and accelerated by a rapidly varying electric field. Lawrence was awarded the 1939 Nobel Prize in Physics for this invention. The cyclotron was the first "cyclical" accelerator. The primary accelerators before the development of the cyclotron were electrostatic accelerators, such as the Cockcroft–Walton generator and the Van de Graaff generator. In these accelerators, particles would cross an accelerating electric field only once. Thus, the energy gained by the particles was limited by the maximum ...
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Craniopharyngiomas
A craniopharyngioma is a rare type of brain tumor derived from pituitary gland embryonic tissue that occurs most commonly in children, but also affects adults. It may present at any age, even in the prenatal and neonatal periods, but peak incidence rates are childhood-onset at 5–14 years and adult-onset at 50–74 years. People may present with bitemporal inferior quadrantanopia leading to bitemporal hemianopsia, as the tumor may compress the optic chiasm. It has a point prevalence around two per 1,000,000. Craniopharyngiomas are distinct from Rathke's cleft tumours and intrasellar arachnoid cysts. Symptoms and signs Craniopharyngiomas are almost always benign. However, as with many brain tumors, their treatment can be difficult, and significant morbidities are associated with both the tumor and treatment. * Headache (obstructive hydrocephalus) * Hypersomnia * Myxedema * Postsurgical weight gain ( hypothalamic obesity) * Polydipsia * Polyuria (diabetes insipidus) * Vision ...
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Acoustic Neuromas
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. The great majority of these VSs (95%) are unilateral, in one ear only. They are called "sporadic" (i.e., by-chance, non-hereditary). Although non-cancerous, they can do harm or even become life-threatening if they gr ...
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Pituitary Tumors
Pituitary adenomas are tumors that occur in the pituitary gland. Most pituitary tumors are benign, approximately 35% are invasive and just 0.1% to 0.2% are carcinomas.Pituitary Tumors Treatment (PDQ®)–Health Professional Version
NIH National Cancer Institute
Pituitary adenomas represent from 10% to 25% of all intracranial , with an estimated prevalence rate in the general population of approximately 17%. Non-invasive and non-secreting pituitary adenomas are considered to be

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Arteriovenous Malformations
An arteriovenous malformation (AVM) is an abnormal connection between arteries and veins, bypassing the capillary system. Usually congenital, this vascular anomaly is widely known because of its occurrence in the central nervous system (usually as a cerebral AVM), but can appear anywhere in the body. The symptoms of AVMs can range from none at all to intense pain or bleeding, and they can lead to other serious medical problems. Signs and symptoms Symptoms of AVMs vary according to their location. Most neurological AVMs produce few to no symptoms. Often the malformation is discovered as part of an autopsy or during treatment of an unrelated disorder (an " incidental finding"); in rare cases, its expansion or a micro-bleed from an AVM in the brain can cause epilepsy, neurological deficit, or pain. The most general symptoms of a cerebral AVM include headaches and epileptic seizures, with more specific symptoms that normally depend on its location and the individual, in ...
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Angiography
Angiography or arteriography is a medical imaging technique used to visualize the inside, or lumen, of blood vessels and organs of the body, with particular interest in the arteries, veins, and the heart chambers. Modern angiography is performed by injecting a radio-opaque contrast agent into the blood vessel and imaging using X-ray based techniques such as fluoroscopy. With time-of-flight (TOF) magnetic resonance it is no longer necessary to use a contrast. The word itself comes from the Greek words ἀνγεῖον ''angeion'' 'vessel' and γράφειν ''graphein'' 'to write, record'. The film or image of the blood vessels is called an ''angiograph'', or more commonly an ''angiogram''. Though the word can describe both an arteriogram and a venogram, in everyday usage the terms angiogram and arteriogram are often used synonymously, whereas the term venogram is used more precisely. The term angiography has been applied to radionuclide angiography and newer vascular ima ...
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X-ray Computed Tomography
An X-ray (also known in many languages as Röntgen radiation) is a form of high-energy electromagnetic radiation with a wavelength shorter than those of ultraviolet rays and longer than those of gamma rays. Roughly, X-rays have a wavelength ranging from 10  nanometers to 10  picometers, corresponding to frequencies in the range of 30  petahertz to 30  exahertz ( to ) and photon energies in the range of 100  eV to 100  keV, respectively. X-rays were discovered in 1895 by the German scientist Wilhelm Conrad Röntgen, who named it ''X-radiation'' to signify an unknown type of radiation.Novelline, Robert (1997). ''Squire's Fundamentals of Radiology''. Harvard University Press. 5th edition. . X-rays can penetrate many solid substances such as construction materials and living tissue, so X-ray radiography is widely used in medical diagnostics (e.g., checking for broken bones) and materials science (e.g., identification of some chemical elements and ...
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Sophiahemmet
Sophiahemmet is a private hospital at Norra Djurgården in Stockholm Stockholm (; ) is the Capital city, capital and List of urban areas in Sweden by population, most populous city of Sweden, as well as the List of urban areas in the Nordic countries, largest urban area in the Nordic countries. Approximately ..., Sweden. It is associated with the Sophiahemmet University College. Its connection with the royal family goes back to 1884 when nursing education sponsored by Queen Sophia was still being conducted at the university. The private hospital was constructed in 1889 at its current location on Valhallavägen. On 1 January 2016, Princess Sofia, Duchess of Värmland was announced as the honorary president of the hospital, replacing Princess Christina, Mrs. Magnuson, who had served as honorary president since 1972. Gallery File:Sophiahemmet Stockholm östhörn 20060509.jpg, The main entrance exterior File:Sofiahemmet interiör 2011a.jpg, The main entrance. File:Sofi ...
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Stereotactic
Stereotactic surgery is a minimally invasive form of surgery, surgical intervention that makes use of a three-dimensional coordinates, coordinate system to locate small targets inside the body and to perform on them some action such as ablation, biopsy, lesion, injection, Deep brain stimulation, stimulation, implantation, radiosurgery (SRS), etc. In theory, any organ system inside the body can be subjected to stereotactic surgery. However, difficulties in setting up a reliable frame of reference (such as bone landmarks, which bear a constant spatial relation to soft tissues) mean that its applications have been, traditionally and until recently, limited to neurosurgery, brain surgery. Besides the brain, biopsy and surgery of the breast are done routinely to locate, sample (biopsy), and remove tissue. Plain X-ray images (radiography, radiographic mammography), computed tomography, and magnetic resonance imaging can be used to Image-guided surgery, guide the procedure. Another acc ...
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Neurosurgery
Neurosurgery or neurological surgery, known in common parlance as brain surgery, is the specialty (medicine), medical specialty that focuses on the surgical treatment or rehabilitation of disorders which affect any portion of the nervous system including the Human brain, brain, spinal cord, peripheral nervous system, and cerebrovascular system. Neurosurgery as a medical specialty also includes non-surgical management of some neurological conditions. Education and context In different countries, there are different requirements for an individual to legally practice neurosurgery, and there are varying methods through which they must be educated. In most countries, neurosurgeon training requires a minimum period of seven years after graduating from medical school. United Kingdom In the United Kingdom, students must gain entry into medical school. The MBBS qualification (Bachelor of Medicine, Bachelor of Surgery) takes four to six years depending on the student's route. The newly qu ...
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Surgery
Surgery is a medical specialty that uses manual and instrumental techniques to diagnose or treat pathological conditions (e.g., trauma, disease, injury, malignancy), to alter bodily functions (e.g., malabsorption created by bariatric surgery such as gastric bypass), to reconstruct or alter aesthetics and appearance (cosmetic surgery), or to remove unwanted tissue (biology), tissues (body fat, glands, scars or skin tags) or foreign bodies. The act of performing surgery may be called a surgical procedure or surgical operation, or simply "surgery" or "operation". In this context, the verb "operate" means to perform surgery. The adjective surgical means pertaining to surgery; e.g. surgical instruments, operating theater, surgical facility or surgical nurse. Most surgical procedures are performed by a pair of operators: a surgeon who is the main operator performing the surgery, and a surgical assistant who provides in-procedure manual assistance during surgery. Modern surgical opera ...
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