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Flow Diverter
A flow diverter is an endovascular prosthesis used to treat intracranial aneurysms. It is placed in the aneurysm's parent artery, covering the neck, in order to divert blood flow and determine a progressive thrombosis of the sac. Flow diverting stents consist of structural Cobalt-chrome or Nitinol alloy wires and often a set of radiopaque wires woven together in a flexible braid. Medical usage Flow diverters are treatment for intracranial aneurysms alternative to endosaccular coil embolization, although the techniques can be combined, especially in large/giant aneurysms. It is mainly effective in wide neck unerupted saccular aneurysms, that are difficult to coil because of the tendency of the coils to fill the parent artery (referred to as prolapse). Another situation is fusiform shape or circumferential aneurysms. Prior to flow diverters many intracranial aneurysms went untreated. Flow diverters can be placed in the parent vessel or within the aneurysm, which are called intras ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prosthesis
In medicine, a prosthesis (plural: prostheses; from grc, πρόσθεσις, prósthesis, addition, application, attachment), or a prosthetic implant, is an artificial device that replaces a missing body part, which may be lost through trauma, disease, or a condition present at birth (congenital disorder). Prostheses are intended to restore the normal functions of the missing body part. Amputee rehabilitation is primarily coordinated by a physiatrist as part of an inter-disciplinary team consisting of physiatrists, prosthetists, nurses, physical therapists, and occupational therapists. Prostheses can be created by hand or with computer-aided design (CAD), a software interface that helps creators design and analyze the creation with computer-generated 2-D and 3-D graphics as well as analysis and optimization tools. Types A person's prosthesis should be designed and assembled according to the person's appearance and functional needs. For instance, a person may need a transra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aneurysm
An aneurysm is an outward bulging, likened to a bubble or balloon, caused by a localized, abnormal, weak spot on a blood vessel wall. Aneurysms may be a result of a hereditary condition or an acquired disease. Aneurysms can also be a nidus (starting point) for clot formation (thrombosis) and embolization. As an aneurysm increases in size, the risk of rupture, which leads to uncontrolled bleeding, increases. Although they may occur in any blood vessel, particularly lethal examples include aneurysms of the Circle of Willis in the brain, aortic aneurysms affecting the thoracic aorta, and abdominal aortic aneurysms. Aneurysms can arise in the heart itself following a heart attack, including both ventricular and atrial septal aneurysms. There are congenital atrial septal aneurysms, a rare heart defect. Etymology The word is from Greek: ἀνεύρυσμα, aneurysma, "dilation", from ἀνευρύνειν, aneurynein, "to dilate". Classification Aneurysms are classified by type, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cobalt-chrome
Cobalt-chrome or cobalt-chromium (CoCr) is a metal alloy of cobalt and chromium. Cobalt-chrome has a very high specific strength and is commonly used in gas turbines, dental implants, and orthopedic implants.ARCAM ASTM F75 CoCr Alloy History Co-Cr alloy was first discovered by in the early 1900s by fusing cobalt and chromium. The alloy was first discovered with many other elements such as and molybdenu ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitinol
Nickel titanium, also known as Nitinol, is a metal alloy of nickel and titanium, where the two elements are present in roughly equal atomic percentages. Different alloys are named according to the weight percentage of nickel; e.g., Nitinol 55 and Nitinol 60. It exhibits the shape memory effect and superelasticity at different temperatures. Nitinol alloys exhibit two closely related and unique properties: the shape memory effect and superelasticity (also called pseudoelasticity). Shape memory is the ability of Nitinol to undergo deformation at one temperature, stay in its deformed shape when the external force is removed, then recover its original, undeformed shape upon heating above its "transformation temperature". Superelasticity is the ability for the metal to undergo large deformations and immediately return to its undeformed shape upon removal of the external load. Nitinol can deform 10–30 times as much as ordinary metals and return to its original shape. Whether Nitinol be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radiopaque
Radiodensity (or radiopacity) is opacity to the radio wave and X-ray portion of the electromagnetic spectrum: that is, the relative inability of those kinds of electromagnetic radiation to pass through a particular material. Radiolucency or hypodensity indicates greater passage (greater transradiancy) to X-ray photonsNovelline, Robert. ''Squire's Fundamentals of Radiology''. Harvard University Press. 5th edition. 1997. . and is the analogue of transparency and translucency with visible light. Materials that inhibit the passage of electromagnetic radiation are called radiodense or radiopaque, while those that allow radiation to pass more freely are referred to as radiolucent. Radiopaque volumes of material have white appearance on radiographs, compared with the relatively darker appearance of radiolucent volumes. For example, on typical radiographs, bones look white or light gray (radiopaque), whereas muscle and skin look black or dark gray, being mostly invisible (radiolucent). Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saccular Aneurysm
An intracranial aneurysm, also known as a brain aneurysm, is a cerebrovascular disorder in which weakness in the wall of a cerebral artery or vein causes a localized dilation or ballooning of the blood vessel. Aneurysms in the posterior circulation (basilar artery, vertebral arteries and posterior communicating artery) have a higher risk of rupture. Basilar artery aneurysms represent only 3–5% of all intracranial aneurysms but are the most common aneurysms in the posterior circulation. Classification Cerebral aneurysms are classified both by size and shape. Small aneurysms have a diameter of less than 15 mm. Larger aneurysms include those classified as large (15 to 25 mm), giant (25 to 50 mm), and super-giant (over 50 mm). Berry (saccular) aneurysms Saccular aneurysms, also known as berry aneurysms, appear as a round outpouching and are the most common form of cerebral aneurysm. Causes include connective tissue disorders, polycystic kidney disease, art ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Artery
An artery (plural arteries) () is a blood vessel in humans and most animals that takes blood away from the heart to one or more parts of the body (tissues, lungs, brain etc.). Most arteries carry oxygenated blood; the two exceptions are the pulmonary and the umbilical arteries, which carry deoxygenated blood to the organs that oxygenate it (lungs and placenta, respectively). The effective arterial blood volume is that extracellular fluid which fills the arterial system. The arteries are part of the circulatory system, that is responsible for the delivery of oxygen and nutrients to all cells, as well as the removal of carbon dioxide and waste products, the maintenance of optimum blood pH, and the circulation of proteins and cells of the immune system. Arteries contrast with veins, which carry blood back towards the heart. Structure The anatomy of arteries can be separated into gross anatomy, at the macroscopic level, and microanatomy, which must be studied with a microscop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemodynamics
Hemodynamics or haemodynamics are the dynamics of blood flow. The circulatory system is controlled by homeostatic mechanisms of autoregulation, just as hydraulic circuits are controlled by control systems. The hemodynamic response continuously monitors and adjusts to conditions in the body and its environment. Hemodynamics explains the physical laws that govern the flow of blood in the blood vessels. Blood flow ensures the transportation of nutrients, hormones, metabolic waste products, oxygen, and carbon dioxide throughout the body to maintain cell-level metabolism, the regulation of the pH, osmotic pressure and temperature of the whole body, and the protection from microbial and mechanical harm. Blood is a non-Newtonian fluid, and is most efficiently studied using rheology rather than hydrodynamics. Because blood vessels are not rigid tubes, classic hydrodynamics and fluids mechanics based on the use of classical viscometers are not capable of explaining haemodynamics. The st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interventional Neuroradiology
Endovascular therapy (EVT), also known as neurointerventional surgery (NIS), interventional neuroradiology (INR), endovascular neurosurgery, and interventional neurology is a medical subspecialty of radiology, neurosurgery, and neurology specializing in minimally invasive image-based technologies and procedures used in diagnosis and treatment of diseases of the head, neck, and spine. History Diagnostic angiography Cerebral angiography was developed by Portuguese neurologist Egas Moniz at the University of Lisbon, in order to identify central nervous system diseases such as tumors or arteriovenous malformations. He performed the first brain angiography in Lisbon in 1927 by injecting an iodinated contrast medium into the internal carotid artery and using the X-rays discovered 30 years earlier by Wilhelm Röntgen, Roentgen in order to visualize the cerebral vessels. In pre-CT and pre-MRI, it was the only tool to observe the structures within the skull and was also used to diagnose ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intracranial Aneurysm
An intracranial aneurysm, also known as a brain aneurysm, is a cerebrovascular disorder in which weakness in the wall of a cerebral artery or vein causes a localized dilation or ballooning of the blood vessel. Aneurysms in the posterior circulation (basilar artery, vertebral arteries and posterior communicating artery) have a higher risk of rupture. Basilar artery aneurysms represent only 3–5% of all intracranial aneurysms but are the most common aneurysms in the posterior circulation. Classification Cerebral aneurysms are classified both by size and shape. Small aneurysms have a diameter of less than 15 mm. Larger aneurysms include those classified as large (15 to 25 mm), giant (25 to 50 mm), and super-giant (over 50 mm). Berry (saccular) aneurysms Saccular aneurysms, also known as berry aneurysms, appear as a round outpouching and are the most common form of cerebral aneurysm. Causes include connective tissue disorders, polycystic kidney disease, art ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Implants (medicine)
Implant can refer to: Medicine *Implant (medicine), or specifically: **Brain implant **Breast implant **Buttock implant **Cochlear implant **Contraceptive implant **Dental implant **Fetal tissue implant **Implantable cardioverter-defibrillator **Orthopedic implant **Prosthetic implant **Retinal implant **Subdermal implant **Transdermal implant Alternative *Alien implants *Extraocular implant *Implant (body modification) * Implant (thought insertion) *Microchip implant (animal) (human) *''The Implant'', a television episode of ''Seinfeld'' See also *History of dental treatments *Implantation (other) *Osseointegration Osseointegration (from Latin ''osseus'' " bony" and ''integrare'' "to make whole") is the direct structural and functional connection between living bone and the surface of a load-bearing artificial implant ("load-bearing" as defined by Albrekt ... * Osseoincorporation {{disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
