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Venous Plexus
In vertebrates, a venous plexus is a normal congregation anywhere in the body of multiple veins. A list of venous plexuses: * Basilar plexus * Batson venous plexus * Epidural venous plexus * External vertebral venous plexuses * Internal vertebral venous plexuses * Pampiniform venous plexus * Prostatic venous plexus * Pterygoid plexus * Rectal venous plexus * Soleal venous plexus * Submucosal venous plexus of the nose * Suboccipital venous plexus * Uterine venous plexus * Vaginal venous plexus * Venous plexus of hypoglossal canal * Vesical venous plexus The vesical venous plexus is a venous plexus situated at the fundus of the urinary bladder. It collects venous blood from the urinary bladder in both sexes, from the accessory sex glands in males, and from the corpora cavernosa of clitoris in fem ... References Veins {{Circulatory-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertebrata
Vertebrates () are animals with a vertebral column (backbone or spine), and a cranium, or skull. The vertebral column surrounds and protects the spinal cord, while the cranium protects the brain. The vertebrates make up the subphylum Vertebrata with some 65,000 species, by far the largest ranked grouping in the phylum Chordata. The vertebrates include mammals, birds, amphibians, and various classes of fish and reptiles. The fish include the jawless Agnatha, and the jawed Gnathostomata. The jawed fish include both the cartilaginous fish and the bony fish. Bony fish include the lobe-finned fish, which gave rise to the tetrapods, the animals with four limbs. Despite their success, vertebrates still only make up less than five percent of all described animal species. The first vertebrates appeared in the Cambrian explosion some 518 million years ago. Jawed vertebrates evolved in the Ordovician, followed by bony fishes in the Devonian. The first amphibians appeared on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Veins
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] |
Basilar Plexus
The basilar venous plexus (transverse or basilar sinus) is a venous plexus of dural venous sinuses situated upon the clivus and posterior aspect of the dorsum sellae of sphenoid bone. It interconnects the two cavernous sinuses as well as the origins of the petrous sinuses. It communicates with the anterior vertebral venous plexus. Clinical significance The basilar venous plexus can sometimes be involved in certain medical conditions, such as a posterior circulation infarction and a cavernous sinus thrombosis Cavernous sinus thrombosis (CST) is the formation of a blood clot within the cavernous sinus, a cavity at the base of the brain which drains deoxygenated blood from the brain back to the heart. This is a rare disorder and can be of two types–sept .... References Veins of the head and neck {{circulatory-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Batson Venous Plexus
The Batson venous plexus (Batson veins) is a network of valveless veins in the human body that connect the deep pelvic veins and thoracic veins (draining the inferior end of the urinary bladder, breast and prostate) to the internal vertebral venous plexuses. Because of their location and lack of valves, they are believed to provide a route for the spread of cancer metastases. These metastases commonly arise from cancer of the pelvic organs such as the rectum and prostate and may spread to the vertebral column or brain. The plexus is named after anatomist Oscar Vivian Batson, who first described it in 1940. Batson's plexus is part of the Cerebrospinal venous system. Batson's venous plexus may also allow the spread of infection in a similar manner. neuroschistomiasis, Urinary tract infections like pyelonephritis have been shown to spread to cause osteomyelitis of the vertebrae via this route. The osteomyelitis in such a case will resolve concurrently with the same antibiotic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epidural Venous Plexus
The epidural venous plexus is a venous plexus embedded within the epidural fat of the vertebral canal. It is situated within the anterior epidural space (the outermost part of the spinal canal). The plexus extends from the skull base to the sacrum. It is surrounded by sparse fat (although its levels increase inferiorly). It drains into the cavernous sinus of the cranial cavity The cranial cavity, also known as intracranial space, is the space within the skull that accommodates the brain. The skull is also known as the cranium. The cranial cavity is formed by eight cranial bones known as the neurocranium that in human ...; it also communicates with the radicular veins. References Spinal cord {{circulatory-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
External Vertebral Venous Plexuses
The external vertebral venous plexuses (extraspinal veins) consist of anterior and posterior plexuses which anastomose freely with each other. They are most prominent in the cervical region where they form anastomoses with the vertebral, occipital, and deep cervical veins. * The anterior external vertebral venous plexuses are situated anteriorly to the vertebral bodies. They communicate with the basivertebral and intervertebral veins, and receive tributaries from the vertebral bodies. * The posterior external vertebral venous plexuses are situated posterior to the vertebral laminae, around and the spinous, transverse, and articular processes. They form anastomoses with the internal vertebral venous plexuses, and drain to vertebral veins, posterior intercostal veins, and lumbar veins The lumbar veins are four pairs of veins running along the inside of the posterior abdominal wall, and drain venous blood from parts of the abdominal wall. Each lumbar vein accompanies a single lum ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internal Vertebral Venous Plexuses
The internal vertebral venous plexuses (intraspinal veins) lie within the vertebral canal in the epidural space, embedded within epidural fat. They receive tributaries from bones, red bone marrow, and spinal cord. They are arranged into four interconnected, vertically oriented vessels - two situated anteriorly, and two posteriorly: *The anterior internal vertebral venous plexus consists of two large plexiform veins situated upon the posterior surfaces of the vertebral bodies and intervertebral discs on either side of the posterior longitudinal ligament (underneath this ligament they are interconnected by transverse branches into which the basivertebral veins open). * The posterior internal vertebral venous plexus consists of two veins situated - one on either side - upon the anterior aspect of the vertebral arches and ligamenta flava. They form anastomoses with posterior external plexuses by way of veins passing through or between the ligamenta flava. The anterior and posterior i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pampiniform Venous Plexus
The pampiniform plexus () is a venous plexus – a network of many small veins found in the human male spermatic cord, and the suspensory ligament of the ovary. In the male, it is formed by the union of multiple testicular veins from the back of the testis and tributaries from the epididymis. In the male The veins of the plexus ascend along the spermatic cord in front of the vas deferens. Below the superficial inguinal ring they unite to form three or four veins, which pass along the inguinal canal, and, entering the abdomen through the deep inguinal ring, coalesce to form two veins. These again unite to form a single vein, the testicular vein, which opens on the right side into the inferior vena cava, at an acute angle, and on the left side into the left renal vein, at a right angle. The pampiniform plexus forms the chief mass of the cord. In addition to its function in venous return from the testes, the pampiniform plexus also plays a role in the temperature regulation of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prostatic Venous Plexus
The prostatic veins form a well-marked prostatic plexus which lies partly in the fascial sheath of the prostate and partly between the sheath and the prostatic capsule. It collects blood from the prostate, and (via the v. dorsalis profunda clitoridis) the corpora cavernosa of penis. It communicates with the pudendal and vesical plexuses. It is sometimes known as "''Santorini's plexus''", named for the Italian anatomist Giovanni Domenico Santorini. Clinical significance The prostatic venous plexus drains into the internal iliac vein which in turn connects with the vertebral venous plexus; this is thought to be the route of bone metastasis Bone metastasis, or osseous metastatic disease, is a category of cancer metastases that result from primary tumor invasions into bones. Bone-originating primary tumors such as osteosarcoma, chondrosarcoma, and Ewing sarcoma are rare; the most commo ... of prostate cancer. References External links * - "The Male Pelvis: The Prostate G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pterygoid Plexus
The pterygoid plexus (; in Merriam-Webster Online Dictionary '. from ''pteryx'', "wing" and ''eidos'', "shape") is a fine venous plexus upon and within the . It drains by a short maxillary vein. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rectal Venous Plexus
The rectal venous plexus (or hemorrhoidal plexus) is the venous plexus surrounding the rectum. It consists of an internal and an external rectal plexus. It is drained by the superior, middle, and inferior rectal veins. It forms a portosystemic (portocaval) anastomosis. This allows rectally administered medications to bypass first pass metabolism. Despite the inclusion of the term "rectal" into the name, the venous plexus is positionally, functionally, and clinically primarily related to the anal canal. Anatomy The rectal venous plexus consists of an external rectal plexus that is situated outside to the muscular wall, and an internal rectal plexus that is situated in the submucosa/deep to the mucosa of the rectum and proximal anal canal at the anorectal junction. Internal rectal plexus The internal plexus presents a series of dilated pouches which are arranged in a circle around the tube, immediately above the anal orifice, and are connected by transverse branches. The intern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Suboccipital Venous Plexus
The suboccipital venous plexus drains deoxygenated blood from the back of the head. It communicates with the external vertebral venous plexuses. The external vertebral venous plexuses travel inferiorly from this suboccipital region to drain into the brachiocephalic vein. The occipital vein joins in the formation of the plexus deep to the musculature of the back and from here drains into the external jugular vein. The plexus surrounds segments of the vertebral artery The vertebral arteries are major artery, arteries of the neck. Typically, the vertebral arteries originate from the subclavian arteries. Each vessel courses superiorly along each side of the neck, merging within the skull to form the single, m .... Veins of the head and neck {{circulatory-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
