Навчальний посібник рекомендований для студентів медичних
INTERPLEURAL SPACE (Mediastinum)
жүктеу/скачать 2,76 Mb. Pdf көрінісі
|
Korenkov Topographic Anatomy (1)
- Бұл бет үшін навигация:
- Mediastinum anterius
- Mediastinum posterius
| INTERPLEURAL SPACE (Mediastinum)
It’s a complex of thoracic cavity organs located between two (right and left) mediastinal pleuras. The mediastinum is limited anteriorly by corpus and manubrium of sternum. Behind – by corpuses of thoracic vertebrae. Below – by diaphragm. Above – by upper foramen of thoracic cage. According to the modern opinion (Basle Nomina Anatomica, Ukrainian standard) the mediastinum is divided into two parts: mediastinum superius and mediastinum inferius. Mediastinum superius is located above the root of the lungs and is separated from mediastinum inferius by conditional surface, which goes through junction point of manubrium of sternum with its corpus, and goes to 4th thoracic vertebra. Pericardium divides the mediastinum inferius into anterior and posterior segments. The mediastinum superius comprises: ● thymus or adipose tissue which replaces it; ● venae brachiocephalici; ● vena cava superior; ● aorta ascendens; ● arcus aortae with its branches; ● the upper part of esophagus; ● ductus thoracicus; ● trachea; ● n. phrenicus and n.vagus. Mediastinum anterius is located between the sternum and pericardium. It comprises internal thoracic vessels (arteries and veins), presternal lymphatic nodes, and inferior segments of thymus. Middle mediastinum comprises pericardium, heart, intracardiac 33 segments of large vessels, bifurcation of trachea, main bronchi, lung arteries and veins, and nn. phrenici which follow the pericardiacophrenica vessels, lateral, pericardial and tracheobronchial lymph nodes. Mediastinum posterius is located between the posterior wall of pericardium and thoracic vertebrae. The mediastinum posterius comprises: esophagus, descending part of aorta, ductus thoracicus, v. azygos and v. haemiazygos, sympathetic trunks and nerves which depart from them, nn. vagi, periesophageal and prevertebral lymph nodes. Organs of mediastinum are covered with adipose tissue which plays an important role in generalization of purulent inflammatory processes. We can distinguish: prepericardial, pretracheal and periesophageal cellular spaces. Prepericardial cellular space is located in mediastinum superius between the posterior surface of sternum and organs (thymus, vessels, pericardium). It has two layers separated by retrosternal fascia of Rudnev (fascia retrosternalis). It begins from the posterior wall of the thymus and ascends to the diaphragm. Its size depends on the length of thymus. The first cellulose layer is thinner. It attaches to the posterior surface of sternum and is called retrosternal space of Diakonov. The second cellular layer is located deeper, between Rudnev fascia and Meier fascia, which is called septum mediastinale. It descends from the posterior part of the capsule of thyroid gland, passes along the anterior surface of trachea, then passes onto posterior surface of pericardium, and ends in tendinous center of diaphragm. This thin fascial plate can be considered as a septum between mediastinum medium and mediastinum posterius. The abscesses of prepericardial cellular space can spread 34 along the anterior surface of pericardium to diaphragm, and then through Larrey’s cleft (sternocostal triangle) and trigonum sternocostale dexter – to preperitoneal fatty tissue. They can also spread up to pretracheal cellular tissue of cervix. We can also ditsinguish the pretracheal cellular space in mediastinum superius. It is limited by aortic arch from the left; v. cava superior, v. azygos and right artery of the lung from the right; tracheal bifurcation behind; thymus and posterior wall of pericardium in front. The periesophageal cellular space is mostly expressed in mediastinum posterius. From above it joins with retropharyngeal space of cervix, and through hiatus aorticus of diaphragm and trigonum lumbocostale (Bochdalek’s foramen) – with extraperitoneal space. Purulent inflammations of mediastinal cellular tissue (mediastinitis) is a severe disease. Cellular tissue of mediastinum comprises significantly expressed reticulum of arterial and venous vessels. The most important arterial vessels are bronchial arteries which take жүктеу/скачать 2,76 Mb. Достарыңызбен бөлісу:
|