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Cryoneurolysis
Cryoneurolysis, also referred to as cryoanalgesia, is a medical procedure that temporarily blocks nerve conduction along peripheral nerve pathways. The procedure, which inserts a small probe to freeze the target nerve, can facilitate complete regeneration of the structure and function of the affected nerve. Cryoneurolysis has been used to treat a variety of painful conditions. Medical uses Cryoneuralysis has been used to relieve pain after thoracotomy, mastectomy, and knee or shoulder arthroplasty. Combined with ultrasound imaging, the procedure can be administered using a hand-held device in an office, and appears to provide an expedient, safe, and nonpharmacological option for treating various chronic pain conditions. Mechanisms of action Nerve anatomy Each nerve is composed of a bundle of axons. Each axon is surrounded by the endoneurium connective tissue layer. These axons are bundled into fascicles surrounded by the perineurium connective tissue layer. Multiple fascicles ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryoprobe
Cryosurgery (with ''cryo'' from the Ancient Greek ) is the use of extreme cold in surgery to destroy abnormal or diseased tissue; thus, it is the surgical application of cryoablation. Cryosurgery has been historically used to treat a number of diseases and disorders, especially a variety of benign and malignant skin conditions. History In 1841, English physician James Arnott described therapeutic applications of extremely cold temperatures, namely a mixture of crushed ice and salt applied locally (to skin or mucous membrane). He theorized his technique was capable of "arresting the accompanying inflammation, and perhaps destroying the vitality of the cancer cell." His works were the first to hypothesize that extreme cold could be used to selectively damage or destroy harmful tissue. Uses Warts, moles, skin tags, solar keratoses, molluscum, Morton's neuroma and small skin cancers are candidates for cryosurgical treatment. Several internal disorders are also treated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nerve Conduction
An action potential (also known as a nerve impulse or "spike" when in a neuron) is a series of quick changes in voltage across a cell membrane. An action potential occurs when the membrane potential of a specific cell rapidly rises and falls. This depolarization then causes adjacent locations to similarly depolarize. Action potentials occur in several types of excitable cells, which include animal cells like neurons and muscle cells, as well as some plant cells. Certain endocrine cells such as pancreatic beta cells, and certain cells of the anterior pituitary gland are also excitable cells. In neurons, action potentials play a central role in cell–cell communication by providing for—or with regard to saltatory conduction, assisting—the propagation of signals along the neuron's axon toward synaptic boutons situated at the ends of an axon; these signals can then connect with other neurons at synapses, or to motor cells or glands. In other types of cells, their main functi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Axonotmesis
Axonotmesis is an injury to the peripheral nerve of one of the extremities of the body. The axons and their myelin sheath are damaged in this kind of injury, but the endoneurium, perineurium and epineurium remain intact. Motor and sensory functions distal to the point of injury are completely lost over time leading to Wallerian degeneration due to ischemia, or loss of blood supply. Axonotmesis is usually the result of a more severe crush or contusion than neurapraxia. Axonotmesis mainly follows a stretch injury. These stretch injuries can either dislocate joints or fracture a limb, due to which peripheral nerves are severed. If the sharp pain from the exposed axon of the nerve is not observed, one can identify a nerve injury from abnormal sensations in their limb. A doctor may ask for a nerve conduction velocity (NCV) test to completely diagnose the issue. If diagnosed as nerve injury, electromyography performed after 3 to 4 weeks shows signs of denervations and fibrillations, or i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Joule–Thomson Effect
In thermodynamics, the Joule–Thomson effect (also known as the Joule–Kelvin effect or Kelvin–Joule effect) describes the temperature change of a Real gas, ''real'' gas or liquid (as differentiated from an ideal gas) when it is expanding; typically caused by the pressure loss from flow through a expansion valve (steam engine), valve or enthalpy#Throttling, porous plug while keeping it insulated so that Adiabatic process, no heat is exchanged with the environment. This procedure is called a ''throttling process'' or ''Joule–Thomson process''. The effect is purely due to deviation from ideality, as any ideal gas has no JT effect. At room temperature, all gases except hydrogen, helium, and neon cool upon expansion by the Joule–Thomson process when being throttled through an orifice; these three gases rise in temperature when forced through a porous plug at room temperature, but lowers in temperature when already at lower temperatures. Most liquids such as Hydraulics, hydr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James Arnott (physician)
James Arnott (1797-1883) was an English physician and pioneer of cryotherapy. Regarded as “the father of modern cryosurgery”, Arnott was the first to utilize extreme cold locally for the destruction of tissue. In 1819, Arnott began his practice of cryotherapy Cryotherapy, sometimes known as cold therapy, is the local or general use of low temperatures in medical therapy. Cryotherapy can be used in many ways, including whole body exposure for therapeutic health benefits or may be used locally to treat ... to freeze tumors in the treatment of breast and uterine cancers. References {{DEFAULTSORT:Arnott, James 1797 births 1883 deaths 19th-century English medical doctors Cryotherapy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hippocrates
Hippocrates of Kos (; ; ), also known as Hippocrates II, was a Greek physician and philosopher of the Classical Greece, classical period who is considered one of the most outstanding figures in the history of medicine. He is traditionally referred to as the "Father of Medicine" in recognition of his lasting contributions to the field, such as the use of prognosis and clinical observation, the systematic categorization of diseases, and the (however misguided) formulation of Humorism, humoral theory. His studies set out the basic ideas of modern-day specialties, including surgery, urology, neurology, acute medicine and Orthopedic surgery, orthopedics. The Hippocratic school of medicine revolutionized ancient Greek medicine, establishing it as a discipline distinct from other fields with which it had traditionally been associated (theurgy and philosophy), thus establishing medicine as a profession. However, the achievements of the writers of the Hippocratic Corpus, the practitioners ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liquid Nitrogen
Liquid nitrogen (LN2) is nitrogen in a liquid state at cryogenics, low temperature. Liquid nitrogen has a boiling point of about . It is produced industrially by fractional distillation of liquid air. It is a colorless, mobile liquid whose viscosity is about one-tenth that of acetone (i.e. roughly one-thirtieth that of water at room temperature). Liquid nitrogen 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 attraction. This is the cause of nitrogen's unusually 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. Thi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryoablation
Cryoablation is a process that uses extreme cold to destroy tissue. Cryoablation is performed using hollow needles (cryoprobes) through which cooled, thermally conductive fluids are circulated. Cryoprobes are positioned adjacent to the target in such a way that the freezing process will destroy the diseased tissue. Once the probes are in place, the attached cryogenic freezing unit removes heat from ("cools") the tip of the probe and by extension from the surrounding tissues. Ablation occurs in tissue that has been frozen by at least three mechanisms: # formation of ice crystals within cells thereby disrupting membranes, and interrupting cellular metabolism among other processes; # coagulation of blood thereby interrupting bloodflow to the tissue in turn causing ischemia and cell death; and # induction of apoptosis, the so-called programmed cell death cascade. The most common application of cryoablation is to ablate solid tumors found in the lung, liver, breast, kidney and prosta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myelin Sheath
Myelin Sheath ( ) is a lipid-rich material that in most vertebrates surrounds the axons of neurons to insulate them and increase the rate at which electrical impulses (called action potentials) pass along the axon. The myelinated axon can be likened to an electrical wire (the axon) with insulating material (myelin) around it. However, unlike the plastic covering on an electrical wire, myelin does not form a single long sheath over the entire length of the axon. Myelin ensheaths part of an axon known as an internodal segment, in multiple myelin layers of a tightly regulated internodal length. The ensheathed segments are separated at regular short unmyelinated intervals, called nodes of Ranvier. Each node of Ranvier is around one micrometre long. Nodes of Ranvier enable a much faster rate of conduction known as saltatory conduction where the action potential recharges at each node to jump over to the next node, and so on till it reaches the axon terminal. At the terminal the a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wallerian Degeneration
Wallerian degeneration is an active process of degeneration that results when a nerve fiber is cut or crushed and the part of the axon distal to the injury (which in most cases is farther from the neuron's cell body) degenerates. A related process of dying back or retrograde degeneration known as 'Wallerian-like degeneration' occurs in many neurodegenerative diseases, especially those where axonal transport is impaired such as amyotrophic lateral sclerosis (ALS) and Alzheimer's disease. Primary culture studies suggest that a failure to deliver sufficient quantities of the essential axonal protein NMNAT2 is a key initiating event. Some studies also have found irreversible electroporation, a potential clinical treatment being researched in porcine models to determine efficacy to treat spinal cord injuries, has contributed to Wallerian degeneration of lumbar nerve roots. Wallerian degeneration occurs after axonal injury in both the peripheral nervous system (PNS) and central nerv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrous Oxide
Nitrous oxide (dinitrogen oxide or dinitrogen monoxide), commonly known as laughing gas, nitrous, or factitious air, among others, is a chemical compound, an Nitrogen oxide, oxide of nitrogen with the Chemical formula, formula . At room temperature, it is a colourless Flammability#Definitions, non-flammable gas, and has a slightly sweet scent and taste. At elevated temperatures, nitrous oxide is a powerful Oxidising agent, oxidiser similar to molecular oxygen. Nitrous oxide has significant Nitrous oxide (medication), medical uses, especially in surgery and dentistry, for its Anesthesia, anaesthetic and Analgesic, pain-reducing effects, and it is on the WHO Model List of Essential Medicines, World Health Organization's List of Essential Medicines. Its colloquial name, "laughing gas", coined by Humphry Davy, describes the Euphoria, euphoric effects upon inhaling it, which cause it to be used as a recreational drug inducing a brief "Dissociative, high". When abused chronically ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
