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Vasa Nervorum
Vasa nervorum are small arteries that provide blood supply to peripheral nerves, specifically to the interior parts of nerves, and their coverings. Associated pathologic conditions Small vessels like vasa vasorum and vasa nervorum are particularly susceptible to external mechanical compression. A decrease in blood flow through the vasa nervorum has been implicated in the development of diabetic neuropathy. Arteritis of the vasa nervorum leads to mononeuritis multiplex or polyneuropathy. Occlusion of vasa nervorum at the level of the epineurial arterioles leads to ischemia of nerves, leading to vasculitic neuropathy. and has been implicated as the cause in a few cases of facial nerve paralysis. During invasive diagnostic or therapeutic procedures, injecting a vasoconstrictor Vasoconstriction is the narrowing of the blood vessels resulting from contraction of the muscular wall of the vessels, in particular the large arteries and small arterioles. The process is the opposite of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nervi Vasculares
Nervi is a former fishing village 12 miles (19 km) northwest of Portofino on the Riviera di Levante, now a seaside resort in Liguria, in northwest Italy. Once an independent ''comune'', it is now a ''quartiere'' of Genoa. Nervi is 4 miles (7 km) east of central Genoa. Geography Nervi is a district of Genoa. At the beginning of the century, it is mentioned as being surrounded with groves of olives, oranges and lemons, and beautiful gardened villas. At 25 meters above sea level, Genoa has a moist climate that is less dusty than the Riviera di Ponente, the part of the Italian Riviera west of Genoa, and is especially in favor with those who suffer from lung complaints. Museums Nervi is home to four significant museums. The Genoa Gallery of Modern Arts, in the former Villa Saluzzo Serra and the Raccolte Frugone, in the former Villa Grimaldi Fassio have paintings, sculptures, and drawings by Italian and other artists from the 19th and 20th centuries. The collection also i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arteries
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] |
Peripheral Nerve
A nerve is an enclosed, cable-like bundle of nerve fibers (called axons) in the peripheral nervous system. A nerve transmits electrical impulses. It is the basic unit of the peripheral nervous system. A nerve provides a common pathway for the electrochemical nerve impulses called action potentials that are transmitted along each of the axons to peripheral organs or, in the case of sensory nerves, from the periphery back to the central nervous system. Each axon, within the nerve, is an extension of an individual neuron, along with other supportive cells such as some Schwann cells that coat the axons in myelin. Within a nerve, each axon is surrounded by a layer of connective tissue called the endoneurium. The axons are bundled together into groups called fascicles, and each fascicle is wrapped in a layer of connective tissue called the perineurium. Finally, the entire nerve is wrapped in a layer of connective tissue called the epineurium. Nerve cells (often called neurons) are f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vasa Vasorum
Vasa vasorum are small blood vessels that comprise a vascular network supplying the walls of large blood vessels, such as elastic arteries (e.g., the aorta) and large veins (e.g., the venae cavae). The name derives . Occasionally two different singular forms are seen: vasa vasis () and vas vasis (). Structure Studies conducted with 3D micro-CT on pig and human arteries from different vascular beds have shown that there are three different types of vasa vasorum: * ''Vasa vasorum internae'', that originate directly from the main lumen of the artery and then branch into the vessel wall. * ''Vasa vasorum externae'', that originate from branches of the main artery and then dive back into the vessel wall of the main artery. * ''Venous vasa vasorae'', that originate within the vessel wall of the artery but then drain into the main lumen or branches of concomitant vein. Depending on the type of vasa vasorum, it penetrates the vessel wall starting at the intimal layer (vasa vasorum ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diabetic Neuropathy
Diabetic neuropathy is various types of nerve damage associated with diabetes mellitus. Symptoms depend on the site of nerve damage and can include motor changes such as weakness; sensory symptoms such as numbness, tingling, or pain; or autonomic changes such as urinary symptoms. These changes are thought to result from microvascular injury involving small blood vessels that supply nerves (vasa nervorum). Relatively common conditions which may be associated with diabetic neuropathy include distal symmetric polyneuropathy; third, fourth, or sixth cranial nerve palsy; mononeuropathy; mononeuropathy multiplex; diabetic amyotrophy; and autonomic neuropathy. Signs and symptoms Diabetic neuropathy can affect any peripheral nerves including sensory neurons, motor neurons, and the autonomic nervous system. Therefore, diabetic neuropathy has the potential to affect essentially any organ system and can cause a range of symptoms. There are several distinct syndromes based on the organ syst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arteritis
Arteritis is the inflammation of the walls of arteries, usually as a result of infection or autoimmune response. Arteritis, a complex disorder, is still not entirely understood. Arteritis may be distinguished by its different types, based on the organ systems affected by the disease. A complication of arteritis is thrombosis, which can be fatal. Arteritis and phlebitis are forms of vasculitis. Signs and Symptoms Symptoms of general arteritis may include: * Inflammation * Fever * Increased production of red blood cells (erythrocytes) * Limping * Reduced pulse Diagnosis Diagnosis of arteritis is based on unusual medical symptoms. Similar symptoms may be caused by a number of other conditions, such as Ehlers-Danlos syndrome and Marfan syndrome (both heritable disorders of connective tissue), tuberculosis, syphilis, spondyloarthropathies, Cogans' syndrome, Buerger's, Behcet's, and Kawasaki disease. Various imaging techniques may be used to diagnose and monitor disease progression. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mononeuritis Multiplex
Peripheral neuropathy, often shortened to neuropathy, is a general term describing disease affecting the peripheral nerves, meaning nerves beyond the brain and spinal cord. Damage to peripheral nerves may impair sensation, movement, gland, or organ function depending on which nerves are affected; in other words, neuropathy affecting motor, sensory, or autonomic nerves result in different symptoms. More than one type of nerve may be affected simultaneously. Peripheral neuropathy may be acute (with sudden onset, rapid progress) or chronic (symptoms begin subtly and progress slowly), and may be reversible or permanent. Common causes include systemic diseases (such as diabetes or leprosy), hyperglycemia-induced glycation, vitamin deficiency, medication (e.g., chemotherapy, or commonly prescribed antibiotics including metronidazole and the fluoroquinolone class of antibiotics (such as ciprofloxacin, levofloxacin, moxifloxacin)), traumatic injury, ischemia, radiation therapy, excessiv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyneuropathy
Polyneuropathy ( poly- + neuro- + -pathy) is damage or disease affecting peripheral nerves (peripheral neuropathy) in roughly the same areas on both sides of the body, featuring weakness, numbness, and burning pain. It usually begins in the hands and feet and may progress to the arms and legs and sometimes to other parts of the body where it may affect the autonomic nervous system. It may be acute or chronic. A number of different disorders may cause polyneuropathy, including diabetes and some types of Guillain–Barré syndrome. Classification Polyneuropathies may be classified in different ways, such as by ''cause'', by ''presentation'', or by ''classes'' of polyneuropathy, in terms of which part of the nerve cell is affected mainly: the axon, the myelin sheath, or the cell body. * ''Distal axonopathy'', is the result of interrupted function of the peripheral nerves. It is the most common response of neurons to metabolic or toxic disturbances, and may be caused by metabolic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epineurium
The epineurium is the outermost layer of dense irregular connective tissue surrounding a peripheral nerve. It usually surrounds multiple nerve fascicles as well as blood vessels which supply the nerve. Smaller branches of these blood vessels penetrate into the perineurium. In addition to blood vessels which supply the nerve, lymphocytes and fibroblasts are also present and contribute to the production of collagen fibers that form the backbone of the epineurium. In addition to providing structural support, lymphocytes and fibroblasts also play a vital role in maintenance and repair of the surrounding tissues. When the spinal nerve leaves the vertebral canal via an intervertebral foramen, two layers of the spinal meninges, the arachnoid and the dura invaginate the nerve to form a dural sleeve of connective tissue, which is the epineurium. The outer portion of this sleeve comprises the external epineurium which permits longitudinal nerve excursion and absorption of longitudina ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arteriole
An arteriole is a small-diameter blood vessel in the microcirculation that extends and branches out from an artery and leads to capillaries. Arterioles have muscular walls (usually only one to two layers of smooth muscle cells) and are the primary site of vascular resistance. The greatest change in blood pressure and velocity of blood flow occurs at the transition of arterioles to capillaries.This function is extremely important because it prevents the thin, one-layer capillaries from exploding upon pressure. The arterioles achieve this decrease in pressure, as they are the site with the highest resistance (a large contributor to total peripheral resistance) which translates to a large decrease in the pressure. Structure Microanatomy In a healthy vascular system the endothelium lines all blood-contacting surfaces, including arteries, arterioles, veins, venules, capillaries, and heart chambers. This healthy condition is promoted by the ample production of nitric oxide by the end ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ischemia
Ischemia or ischaemia is a restriction in blood supply to any tissue, muscle group, or organ of the body, causing a shortage of oxygen that is needed for cellular metabolism (to keep tissue alive). Ischemia is generally caused by problems with blood vessels, with resultant damage to or dysfunction of tissue i.e. hypoxia and microvascular dysfunction. It also implies local hypoxia in a part of a body resulting from constriction (such as vasoconstriction, thrombosis, or embolism). Ischemia causes not only insufficiency of oxygen, but also reduced availability of nutrients and inadequate removal of metabolic wastes. Ischemia can be partial (poor perfusion) or total blockage. The inadequate delivery of oxygenated blood to the organs must be resolved either by treating the cause of the inadequate delivery or reducing the oxygen demand of the system that needs it. For example, patients with myocardial ischemia have a decreased blood flow to the heart and are prescribed with medi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vasculitic Neuropathy
Vasculitic neuropathy is a peripheral neuropathic disease. In a vasculitic neuropathy there is damage to the vessels that supply blood to the nerves. It can be as part of a systemic problem or can exist as a single-organ issue only affecting the peripheral nervous system (PNS). It is diagnosed with the use of electrophysiological testing, blood tests, nerve biopsy and clinical examination. It is a serious medical condition that can cause prolonged morbidity and disability and generally requires treatment. Treatment depends on the type but it is mostly with corticosteroids or immunomodulating therapies. Types There are three main categories of vasculitic neuropathies: primary, secondary and non-systemic. Primary systemic vasculitic neuropathy Some patients with systemic vasculitis will have their multi-organ disease spread to the peripheral nervous system; this is primary vasculitic neuropathy. Some examples of systemic vasculitic disease are: IgA vasculitis, Hypocomplementem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
