|
Perforator Veins
Perforator veins are so called because they perforate the deep fascia of muscles, to connect the superficial veins to the deep veins where they drain. Perforator veins play an essential role in maintaining normal blood draining. They have valves which prevent blood flowing back ( regurgitation) from deep to superficial veins in muscular systole or contraction. Location Perforator veins exist along the length of the lower limb, in greater number in the leg (anatomical ref to below knee) than in the thigh. Some veins are named after the physician who first described them: *Dodd's perforator at the inferior 1/3 of the thigh *Boyd's perforator at the knee level *Cockett's perforators at the inferior 2/3 of the leg (usually there are three: superior medium and inferior Cockett perforators) Others have the name of the deep vein where they drain: *Medial gastrocnemius perforator, draining into the gastrocnemius vein *Fibular perforators, usually two, one superior near the lateral as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deep Fascia
Deep fascia (or investing fascia) is a fascia, a layer of dense connective tissue that can surround individual muscles and groups of muscles to separate into fascial compartments. This fibrous connective tissue interpenetrates and surrounds the muscles, bones, nerves, and blood vessels of the body. It provides connection and communication in the form of aponeuroses, ligaments, tendons, retinaculum, retinacula, joint capsules, and septum, septa. The deep fasciae envelop all bone (periosteum and endosteum); cartilage (perichondrium), and blood vessels (tunica externa) and become specialized in muscles (epimysium, perimysium, and endomysium) and nerves (epineurium, perineurium, and endoneurium). The high density of collagen fibers gives the deep fascia its strength and integrity. The amount of elastin fiber determines how much extensibility and resilience it will have. Examples Examples include: * Fascia lata * Deep fascia of leg * Brachial fascia * Buck's fascia Fascial dynamics D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muscle
Muscle is a soft tissue, one of the four basic types of animal tissue. There are three types of muscle tissue in vertebrates: skeletal muscle, cardiac muscle, and smooth muscle. Muscle tissue gives skeletal muscles the ability to muscle contraction, contract. Muscle tissue contains special Muscle contraction, contractile proteins called actin and myosin which interact to cause movement. Among many other muscle proteins, present are two regulatory proteins, troponin and tropomyosin. Muscle is formed during embryonic development, in a process known as myogenesis. Skeletal muscle tissue is striated consisting of elongated, multinucleate muscle cells called muscle fibers, and is responsible for movements of the body. Other tissues in skeletal muscle include tendons and perimysium. Smooth and cardiac muscle contract involuntarily, without conscious intervention. These muscle types may be activated both through the interaction of the central nervous system as well as by innervation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Superficial Vein
Superficial veins are veins that are close to the surface of the body, as opposed to deep veins, which are far from the surface. Superficial veins are not paired with an artery, unlike the deep veins, which are typically associated with an artery of the same name. Superficial veins are important physiology, physiologically for cooling of the body. When the body is too hot, the body shunts blood from the deep veins to the superficial veins to facilitate heat transfer to the body's surroundings. Superficial veins are often visible underneath the skin. Those below the level of the heart tend to bulge out, which can be readily witnessed in the hand, where the veins bulge significantly less after the arm has been raised above the head for a short time. Veins become more visually prominent when lifting heavy weight, especially after a period of proper strength training. Physiologically, the superficial veins are not as important as the deep veins (as they carry less blood) and ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deep Vein
A deep vein is a vein that is deep in the body. This contrasts with superficial veins that are close to the body's surface. Deep veins are almost always beside an artery with the same name (e.g. the femoral vein is beside the femoral artery). Collectively, they carry the vast majority of the blood. Occlusion of a deep vein can be life-threatening and is most often caused by thrombosis. Occlusion of a deep vein by thrombosis is called ''deep vein thrombosis''. Because of their location deep within the body, operation on these veins can be difficult. List *Internal jugular vein Upper limb * Brachial vein * Axillary vein *Subclavian vein Lower limb *Common femoral vein *Femoral vein * Profunda femoris vein * Popliteal vein * Peroneal vein * Anterior tibial vein *Posterior tibial vein The posterior tibial veins are veins of the leg in humans. They drain the posterior compartment of the leg and the plantar surface of the foot to the popliteal vein. Structure The poste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Venous Valves
Veins () are blood vessels in the circulatory system of humans and most other animals that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are those of the pulmonary and fetal circulations which carry oxygenated blood to the heart. In the systemic circulation, arteries carry oxygenated blood away from the heart, and veins return deoxygenated blood to the heart, in the deep veins. There are three sizes of veins: large, medium, and small. Smaller veins are called venules, and the smallest the post-capillary venules are microscopic that make up the veins of the microcirculation. Veins are often closer to the skin than arteries. Veins have less smooth muscle and connective tissue and wider internal diameters than arteries. Because of their thinner walls and wider lumens they are able to expand and hold more blood. This greater capacity gives them the term of ''capacitance vessels''. At any time, nearly 70% of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Regurgitation (circulation)
Regurgitation is blood flow in the opposite direction from normal, as the backward flowing of blood into the heart or between heart chambers. It is the circulatory equivalent of backflow in engineered systems. It is sometimes called reflux. Types of heart valve regurgitation The various types of heart valve regurgitation via insufficiency are as follows: # Aortic regurgitation: the backflow of blood from the aorta into the left ventricle, owing to insufficiency of the aortic semilunar valve; it may be chronic or acute. # Mitral regurgitation: the backflow of blood from the left ventricle into the left atrium, owing to insufficiency of the mitral valve; it may be acute or chronic, and is usually due to mitral valve prolapse, rheumatic heart disease, or a complication of cardiac dilatation. See also Mitral regurgitation. # Pulmonic regurgitation: the backflow of blood from the pulmonary artery into the right ventricle, owing to insufficiency of the pulmonic semilunar v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Systole (medicine)
Systole ( ) is the part of the cardiac cycle during which some chambers of the heart contract after refilling with blood. Its contrasting phase is diastole, the relaxed phase of the cardiac cycle when the chambers of the heart are refilling with blood. Etymology The term originates, via Neo-Latin, from Ancient Greek (''sustolē''), from (''sustéllein'' 'to contract'; from ''sun'' 'together' + ''stéllein'' 'to send'), and is similar to the use of the English term ''to squeeze''. Terminology, general explanation The mammalian heart has four chambers: the left atrium above the left ventricle (lighter pink, see graphic), which two are connected through the mitral (or bicuspid) valve; and the right atrium above the right ventricle (lighter blue), connected through the tricuspid valve. The atria are the receiving blood chambers for the circulation of blood and the ventricles are the discharging chambers. In late ventricular diastole, the atrial chambers contract and send ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Normal Mapping
In 3D computer graphics, normal mapping, or Dot3 bump mapping, is a texture mapping technique used for faking the lighting of bumps and dents – an implementation of bump mapping. It is used to add details without using more polygonal modeling, polygons. A common use of this technique is to greatly enhance the appearance and details of a low poly, low polygon model by generating a normal map from a high polygon model or Heightmap, height map. Normal maps are commonly stored as regular RGB images where the RGB components correspond to the X, Y, and Z coordinates, respectively, of the surface normal. History In 1978 Jim Blinn described how the normals of a surface could be perturbed to make geometrically flat faces have a detailed appearance. The idea of taking geometric details from a high polygon model was introduced in "Fitting Smooth Surfaces to Dense Polygon Meshes" by Krishnamurthy and Levoy, Proc. SIGGRAPH 1996, where this approach was used for creating displacement mappi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Venous Ulcer
Venous ulcer is defined by the American Venous Forum as "a full-thickness defect of skin, most frequently in the ankle region, that fails to heal spontaneously and is sustained by chronic venous disease, based on venous duplex ultrasound testing." Venous ulcers are wounds that are thought to occur due to improper functioning of venous valves, usually of the legs (hence leg ulcers). They are an important cause of chronic wounds, affecting 1% of the population. Venous ulcers develop mostly along the medial distal leg, and can be painful with negative effects on quality of life. Exercise, together with compression stockings, increases healing. The NICE guideline recommends that everyone with a venous leg ulcer, even if healed, should be referred to a vascular specialist for venous duplex ultrasound and assessment for endovenous surgery. Signs and symptoms Signs and symptoms of venous ulcers include: * Moderate pain, which improves on elevation (unlike arterial ulcers which wors ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultrasonography Of Chronic Insufficiency Of The Legs
Ultrasonography of suspected or previously confirmed chronic venous insufficiency of leg veins is a risk-free, non-invasive procedure. It gives information about the anatomy, physiology and pathology of mainly superficial veins. As with heart ultrasound (echocardiography) studies, venous ultrasonography requires an understanding of hemodynamics in order to give useful examination reports. In chronic venous insufficiency, sonographic examination is of most benefit; in confirming varicose disease, making an assessment of the hemodynamics, and charting the progression of the disease and its response to treatment. It has become the reference standard for examining the condition and hemodynamics of the lower limb veins. Particular veins of the deep venous system (DVS), and the superficial venous system (SVS) are looked at. The great saphenous vein (GSV), and the small saphenous vein (SSV) are superficial veins which drain into respectively, the common femoral vein and the popliteal ve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surgical Incision
A surgical incision is a cut made through the skin and soft tissue to facilitate an operation or procedure. Often, multiple incisions are possible for an operation. In general, a surgical incision is made as small and unobtrusive as possible to facilitate safe and timely operating conditions and recovery. Anatomy Surgical incisions are planned based on the expected extent of exposure needed for the specific operation planned. Within each region of the body, several incisions are common. Head and neck * Wilde's incision – This post-aural incision is used for a variant mastoiditis drainage, and was named after Sir William Wilde, an ENT surgeon in Dublin who first described it at the end of the nineteenth century. His son, Oscar Wilde's, death was stated by his doctors to be due to meningitis stemming from an ear infection. He had recently had an operation, believed by some to be a mastoidectomy. Chest * Median sternotomy – This is the primary incision used for card ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Minimally Invasive Procedure
Minimally invasive procedures (also known as minimally invasive surgeries) encompass surgical techniques that limit the size of incisions needed, thereby reducing wound healing time, associated pain, and risk of infection. Surgery by definition is invasive, and many operations requiring incisions of some size are referred to as ''open surgery''. Incisions made during open surgery can sometimes leave large wounds that may be painful and take a long time to heal. Advancements in medical technologies have enabled the development and regular use of minimally invasive procedures. For example, endovascular aneurysm repair, a minimally invasive surgery, has become the most common method of repairing abdominal aortic aneurysms in the US as of 2003. The procedure involves much smaller incisions than the corresponding open surgery procedure of open aortic surgery. Interventional radiologists were the forerunners of minimally invasive procedures. Using imaging techniques, radiologi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
