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Thalamotomy
Thalamotomy ( el, θάλαμος, thalamus, lit =chamber; el, τομή , tomē, lit=cut, slice) is a surgical procedure in which an opening is made into the thalamus to improve the overall brain function in patients. First introduced in the 1950s, it is primarily effective for tremors such as those associated with Parkinson's disease, where a selected portion of the thalamus is surgically destroyed ( ablated). Neurosurgeons use specialized equipment to precisely locate an area of the thalamus, usually choosing to work on only one side (the side opposite that of the worst tremors). Bilateral procedures are poorly tolerated because of increased complications and risk, including vision and speech problems. The positive effects on tremors are immediate. Other less destructive procedures are sometimes preferred, such as subthalamic deep brain stimulation, since this procedure can also improve tremors and other symptoms of PD. Indications Thalamotomy is a complex procedure perform ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stereotactic
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. 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 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 (radiographic mammography), computed tomography, and magnetic resonance imaging can be used to guide the procedure. Another accepted form of "stereotactic" is "stereotaxic". The word roots are '' stereo-'', a prefix d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deep-brain Stimulation
Deep brain stimulation (DBS) is a neurosurgical procedure involving the placement of a medical device called a neurostimulator, which sends electrical impulses, through implanted electrodes, to specific targets in the brain (the brain nucleus) for the treatment of movement disorders, including Parkinson's disease, essential tremor, dystonia, and other conditions such as obsessive-compulsive disorder (OCD) and epilepsy. While its underlying principles and mechanisms are not fully understood, DBS directly changes brain activity in a controlled manner. DBS has been approved by the Food and Drug Administration as a treatment for essential tremor and Parkinson's disease (PD) since 1997. DBS was approved for dystonia in 2003, obsessive–compulsive disorder (OCD) in 2009, and epilepsy in 2018. DBS has been studied in clinical trials as a potential treatment for chronic pain for various affective disorders, including major depression. It is one of few neurosurgical procedures that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thalamic Stimulator
A thalamic stimulator is a medical device that can suppress tremors, such as those caused by Parkinson's disease or essential tremor. It was approved for use by the Food and Drug Administration (FDA) on August 4, 1997. Installation is invasive, so it is typically only used when the tremors are incapacitating, and medication is ineffective. Typically, one or more electrodes are implanted in the brain, with subcutaneous leads to a neurostimulator, which may also be implanted. The electrodes stimulate the area of the thalamus, specifically the part of the brain that controls movement and muscle function. It is notable that the presence of thalamic stimulators significantly changes ECG patterns, and prevents the use of MRI. It is sometimes regarded as a better alternative to pallidotomy or thalamotomy because it is non-permanent. For optimal installation, the patient is awake during the procedure, and talks to the surgeon to find the best placement. Once in place, the device ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thalamocortical Dysrhythmia
Thalamocortical dysrhythmia (TCD) is a theoretical framework in which neuroscientists try to explain the positive and negative symptoms induced by neuropsychiatric disorders like Parkinson's Disease, neurogenic pain, tinnitus, visual snow syndrome, schizophrenia, obsessive–compulsive disorder, depressive disorder and epilepsy. In TCD, normal thalamocortical resonance is disrupted by changes in the behaviour of neurons in the thalamus. TCD can be treated with neurosurgical methods like the central lateral thalamotomy, which due to its invasiveness is only used on patients that have proven resistant to conventional therapies. Background At the base of the theory lies diminished excitatory or increased inhibitory input at the thalamic level. This leads to a switch of the thalamocortical neurons from tonic to burst firing and subsequently entrains thalamic and cortical areas with pathological oscillations at around 5 Hz. Evidence Evidence for TCD comes from Magnetoencephalogr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thalamus
The thalamus (from Greek θάλαμος, "chamber") is a large mass of gray matter located in the dorsal part of the diencephalon (a division of the forebrain). Nerve fibers project out of the thalamus to the cerebral cortex in all directions, allowing hub-like exchanges of information. It has several functions, such as the relaying of sensory signals, including motor signals to the cerebral cortex and the regulation of consciousness, sleep, and alertness. Anatomically, it is a paramedian symmetrical structure of two halves (left and right), within the vertebrate brain, situated between the cerebral cortex and the midbrain. It forms during embryonic development as the main product of the diencephalon, as first recognized by the Swiss embryologist and anatomist Wilhelm His Sr. in 1893. Anatomy The thalamus is a paired structure of gray matter located in the forebrain which is superior to the midbrain, near the center of the brain, with nerve fibers projecting out to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Neurological Association
The American Neurological Association (ANA) is a professional society of academic neurologists and neuroscientists devoted to advancing the goals of academic neurology; to training and educating neurologists and other physicians in the neurologic sciences; and to expanding both our understanding of diseases of the nervous system and our ability to treat them. It was founded in June 1875. See also * American Medical Association * American Psychiatric Association * Transactions of the American Neurological Association * Sarah McNutt Sarah Jane McNutt (July 22, 1839 – September 10, 1930) was an American physician, notable as the first woman inducted into the American Neurological Association. McNutt was a founder of the Babies' Hospital in New York City, now known as Morgan ... References External links * Medical associations based in the United States Neurology organizations Organizations established in 1875 Medical and health organizations based in New Jersey ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multiple System Atrophy
Multiple system atrophy (MSA) is a rare neurodegenerative disorder characterized by autonomic dysfunction, tremors, slow movement, muscle rigidity, and postural instability (collectively known as parkinsonism) and ataxia. This is caused by progressive degeneration of neurons in several parts of the brain including the basal ganglia, inferior olivary nucleus, and cerebellum. Many people affected by MSA experience dysfunction of the autonomic nervous system, which commonly manifests as orthostatic hypotension, impotence, loss of sweating, dry mouth and urinary retention and incontinence. Palsy of the vocal cords is an important and sometimes initial clinical manifestation of the disorder. A modified form of the alpha-synuclein protein within affected neurons may cause MSA. About 55% of MSA cases occur in men, with those affected first showing symptoms at the age of 50–60 years. MSA often presents with some of the same symptoms as Parkinson's disease. However, those with MSA gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemiballismus
Hemiballismus or hemiballism is a basal ganglia syndrome resulting from damage to the subthalamic nucleus in the basal ganglia. Hemiballismus is a rare hyperkinetic movement disorder, that is characterized by violent involuntary limb movements, on one side of the body, and can cause significant disability. ''Ballismus'' affects both sides of the body and is much rarer. Symptoms can decrease during sleep. Hemiballismus differs from chorea in that the movements occur in the proximal limbs whereas in chorea the limb movements are in the distal limbs. Also in chorea the movements are more dance-like, flowing from one region to another. Presentation ''Ballism'' was defined by Meyers in 1968Meyer, R. (1968) Ballismus. In: Vinken, P.J. and Bruyn, G.W. (Eds.), Handbook of Clinical Neurology, Vol. 6, North-Holland Publishing Co., Amsterdam, pp. 476-490. as "Repetitive, but constantly varying, large amplitude involuntary movements of the proximal parts of the limbs. This activity is al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chorea
Chorea (or choreia, occasionally) is an abnormal involuntary movement disorder, one of a group of neurological disorders called dyskinesias. The term ''chorea'' is derived from the grc, χορεία ("dance"; see choreia), as the quick movements of the feet or hands are comparable to dancing. The term hemichorea refers to chorea of one side of the body, such as chorea of one arm but not both (analogous to hemiballismus). Presentation Chorea is characterized by brief, semi-directed, irregular movements that are not repetitive or rhythmic, but appear to flow from one muscle to the next. These 'dance-like' movements of chorea often occur with athetosis, which adds twisting and writhing movements. Walking may become difficult, and include odd postures and leg movements. Unlike ataxia, which affects the quality of voluntary movements, or Parkinsonism, which is a hindrance of voluntary movements, the movements of chorea and ballism occur on their own, without conscious effort. Thus, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liquid Nitrogen
Liquid nitrogen—LN2—is nitrogen in a liquid state at low temperature. Liquid nitrogen has a boiling point of about . It is produced industrially by fractional distillation of liquid air. It is a colorless, low viscosity liquid that is widely used as a coolant. Physical properties The diatomic character of the N2 molecule is retained after liquefaction. The weak van der Waals interaction between the N2 molecules results in little interatomic interaction, manifested in its very low boiling point. The temperature of liquid nitrogen can readily be reduced to its freezing point by placing it in a vacuum chamber pumped by a vacuum pump. Liquid nitrogen's efficiency as a coolant is limited by the fact that it boils immediately on contact with a warmer object, enveloping the object in an insulating layer of nitrogen gas bubbles. This effect, known as the Leidenfrost effect, occurs when any liquid comes in contact with a surface which is significantly hotter than its boiling ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic Resonance Imaging
Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to form pictures of the anatomy and the physiological processes of the body. MRI scanners use strong magnetic fields, magnetic field gradients, and radio waves to generate images of the organs in the body. MRI does not involve X-rays or the use of ionizing radiation, which distinguishes it from CT and PET scans. MRI is a medical application of nuclear magnetic resonance (NMR) which can also be used for imaging in other NMR applications, such as NMR spectroscopy. MRI is widely used in hospitals and clinics for medical diagnosis, staging and follow-up of disease. Compared to CT, MRI provides better contrast in images of soft-tissues, e.g. in the brain or abdomen. However, it may be perceived as less comfortable by patients, due to the usually longer and louder measurements with the subject in a long, confining tube, though "Open" MRI designs mostly relieve this. Additionally, implants and oth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neurosurgeon
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. 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 States In the United States, a neurosurgeon must generally complete four years of undergraduate education, four years of medical school, and seven years of residency (PGY-1-7). Most, but not all, residency programs have some component of basic science or clinical research. Neurosurgeons may pursue additional training in the form of a fellowship after residency, or, in some cases, as a senior resid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
