|
Hemiazygos Vein
The hemiazygos vein (vena azygos minor inferior) is a vein running superiorly in the lower thoracic region, just to the left side of the vertebral column. Structure The hemiazygos vein and the accessory hemiazygos vein, when taken together, essentially serve as the left-sided equivalent of the azygos vein. That is, the azygos vein serves to drain most of the posterior intercostal veins on the right side of the body, and the hemiazygos vein and the accessory hemiazygos vein drain most of the posterior intercostal veins on the left side of the body. Specifically, the hemiazygos vein mirrors the bottom part of the azygos vein. The structure of the hemiazygos vein is often variable. It usually begins in the left ascending lumbar vein or renal vein, and passes upward through the left crus of the diaphragm to enter the thorax. It continues ascending on the left side of the vertebral column, and around the level of the ninth thoracic vertebra, it passes rightward across the column, behin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Renal Vein
The renal veins are large-calibre veins that drain blood filtered by the kidneys into the inferior vena cava. There is one renal vein draining each kidney. Because the inferior vena cava is on the right half of the body, the left renal vein is longer than the right one. Structure One renal vein drains each kidney. A renal vein is situated anterior to its corresponding accompanying renal artery. The renal veins empty into the inferior vena cava, entering it at nearly a 90° angle. Due to the right-ward displacement of the inferior vena cava from the midline, the left renal vein is some 3 times longer than the right one (~7.5 cm and ~2.5 cm, respectively). The renal vein divides into 4 divisions upon entering the kidney: * the anterior branch which receives blood from the anterior portion of the kidney and, * the posterior branch which receives blood from the posterior portion. Tributaries Because the tributaries of the inferior vena cava are not bilaterally symmetrical, the l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thoracic Duct
In human anatomy, the thoracic duct is the larger of the two lymph ducts of the lymphatic system. It is also known as the ''left lymphatic duct'', ''alimentary duct'', ''chyliferous duct'', and ''Van Hoorne's canal''. The other duct is the right lymphatic duct. The thoracic duct carries chyle, a liquid containing both lymph and emulsified fats, rather than pure lymph. It also collects most of the lymph in the body other than from the right thorax, arm, head, and neck (which are drained by the right lymphatic duct). The thoracic duct usually starts from the level of the twelfth thoracic vertebra (T12) and extends to the root of the neck. It drains into the systemic (blood) circulation at the junction of the left subclavian and internal jugular veins, at the commencement of the brachiocephalic vein. When the duct ruptures, the resulting flood of liquid into the pleural cavity is known as chylothorax. Structure In adults, the thoracic duct is typically 38–45 cm in length an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Esophagus
The esophagus (American English) or oesophagus (British English; both ), non-technically known also as the food pipe or gullet, is an organ in vertebrates through which food passes, aided by peristaltic contractions, from the pharynx to the stomach. The esophagus is a fibromuscular tube, about long in adults, that travels behind the trachea and heart, passes through the diaphragm, and empties into the uppermost region of the stomach. During swallowing, the epiglottis tilts backwards to prevent food from going down the larynx and lungs. The word ''oesophagus'' is from Ancient Greek οἰσοφάγος (oisophágos), from οἴσω (oísō), future form of φέρω (phérō, “I carry”) + ἔφαγον (éphagon, “I ate”). The wall of the esophagus from the lumen outwards consists of mucosa, submucosa (connective tissue), layers of muscle fibers between layers of fibrous tissue, and an outer layer of connective tissue. The mucosa is a stratified squamous epithel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aorta
The aorta ( ) is the main and largest artery in the human body, originating from the left ventricle of the heart and extending down to the abdomen, where it splits into two smaller arteries (the common iliac arteries). The aorta distributes oxygenated blood to all parts of the body through the systemic circulation. Structure Sections In anatomical sources, the aorta is usually divided into sections. One way of classifying a part of the aorta is by anatomical compartment, where the thoracic aorta (or thoracic portion of the aorta) runs from the heart to the diaphragm. The aorta then continues downward as the abdominal aorta (or abdominal portion of the aorta) from the diaphragm to the aortic bifurcation. Another system divides the aorta with respect to its course and the direction of blood flow. In this system, the aorta starts as the ascending aorta, travels superiorly from the heart, and then makes a hairpin turn known as the aortic arch. Following the aortic arch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thoracic Vertebra
In vertebrates, thoracic vertebrae compose the middle segment of the vertebral column, between the cervical vertebrae and the lumbar vertebrae. In humans, there are twelve thoracic vertebrae and they are intermediate in size between the cervical and lumbar vertebrae; they increase in size going towards the lumbar vertebrae, with the lower ones being much larger than the upper. They are distinguished by the presence of facets on the sides of the bodies for articulation with the heads of the ribs, as well as facets on the transverse processes of all, except the eleventh and twelfth, for articulation with the tubercles of the ribs. By convention, the human thoracic vertebrae are numbered T1–T12, with the first one (T1) located closest to the skull and the others going down the spine toward the lumbar region. General characteristics These are the general characteristics of the second through eighth thoracic vertebrae. The first and ninth through twelfth vertebrae contain certain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thorax
The thorax or chest is a part of the anatomy of humans, mammals, and other tetrapod animals located between the neck and the abdomen. In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main divisions of the creature's body, each of which is in turn composed of multiple segments. The human thorax includes the thoracic cavity and the thoracic wall. It contains organs including the heart, lungs, and thymus gland, as well as muscles and various other internal structures. Many diseases may affect the chest, and one of the most common symptoms is chest pain. Etymology The word thorax comes from the Greek θώραξ ''thorax'' "breastplate, cuirass, corslet" via la, thorax. Plural: ''thoraces'' or ''thoraxes''. Human thorax Structure In humans and other hominids, the thorax is the chest region of the body between the neck and the abdomen, along with its internal organs and other contents. It is mostly protected and supported by the rib cage, spi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crus Of Diaphragm
The crus of diaphragm (pl. crura), refers to one of two tendinous structures that extends below the diaphragm to the vertebral column. There is a right crus and a left crus, which together form a tether for muscular contraction. They take their name from their leg-shaped appearance – ''crus'' meaning ''leg'' in Latin. Structure The crura originate from the front of the bodies and intervertebral fibrocartilage of the lumbar vertebrae. They are tendinous and blend with the anterior longitudinal ligament of the vertebral column. * The ''right crus'', larger and longer than the left, arises from the front of the bodies and intervertebral fibrocartilages of the upper three lumbar vertebrae. * The ''left crus'' arises from the corresponding parts of the upper two lumbar vertebrae only. The medial tendinous margins of the crura pass anteriorly and medialward, and meet in the middle line to form an arch across the front of the aorta known as the median arcuate ligament; this arch is of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ascending Lumbar Vein
The ascending lumbar vein is a vein that runs up through the lumbar region on the side of the vertebral column. Structure The ascending lumbar vein is a paired structure (i.e. one each for the right and left sides of the body). It starts at the common iliac veins. It runs superiorly, intersecting with the lumbar veins as it crosses them. It passes behind the psoas major muscle, but in front of the lumbar vertebrae. When the ascending lumbar vein crosses the subcostal vein, it becomes one of the following: * the azygos vein (in the case of the ''right'' ascending lumbar vein). * the hemiazygos vein (in the case of the ''left'' ascending lumbar vein). # The first and second lumbar veins ends in the ascending lumbar vein(the third and fourth lumbar veins open into the posterior aspect of the inferior vena cava) Clinical significance Contrast medium may be injected into the ascending lumbar vein via the femoral vein in order to visualise the spinal canal. The ascending lumbar vei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Venæ Cavæ
In anatomy, the venae cavae (; singular: vena cava ; ) are two large veins (great vessels) that return deoxygenated blood from the body into the heart. In humans they are the superior vena cava and the inferior vena cava, and both empty into the right atrium. They are located slightly off-center, toward the right side of the body. The right atrium receives deoxygenated blood through coronary sinus and two large veins called venae cavae. The inferior vena cava (or caudal vena cava in some animals) travels up alongside the abdominal aorta with blood from the lower part of the body. It is the largest vein in the human body. MadSci Network: Anatomy. Retrieved 19 September 2013. The superior vena cava (or cranial vena cava in animals) is above the heart, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Posterior Intercostal Veins
The posterior intercostal veins are veins that drain the intercostal spaces posteriorly. They run with their corresponding posterior intercostal artery on the underside of the rib, the vein superior to the artery. Each vein also gives off a dorsal branch that drains blood from the muscles of the back. There are eleven posterior intercostal veins on each side. Their patterns are variable, but they are commonly arranged as: * The 1st posterior intercostal vein, supreme intercostal vein, drains into the brachiocephalic vein or the vertebral vein. * The 2nd and 3rd (and often 4th) posterior intercostal veins drain into the superior intercostal vein. * The remaining posterior intercostal veins drain into the azygos vein on the right, or the hemiazygos and accessory hemiazygos vein The accessory hemiazygos vein, also called the superior hemiazygous vein, is a vein on the left side of the vertebral column that generally drains the fourth through eighth intercostal spaces on the left ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Accessory Hemiazygos Vein
The accessory hemiazygos vein, also called the superior hemiazygous vein, is a vein on the left side of the vertebral column that generally drains the fourth through eighth intercostal spaces on the left side of the body. Structure The accessory hemiazygos vein varies inversely in size with the left superior intercostal vein. It usually receives the posterior intercostal veins from the 4th, 5th, 6th, 7th, and 8th intercostal spaces between the left superior intercostal vein and highest tributary of the hemiazygos vein; the left bronchial vein sometimes opens into it. The vein usually crosses the body of the eighth thoracic vertebra to join the azygos vein The azygos vein is a vein running up the right side of the thoracic vertebral column draining itself towards the superior vena cava. It connects the systems of superior vena cava and inferior vena cava and can provide an alternative path for blo .... Alternatively, it ends in the hemiazygos vein. When this vein is small ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
