Variations and abnormalities of the respiratory, pleura and mediastinal organs

Outer nose. The number of cartilage of the nose varies, often their number is less than usual. In 20% of cases in the back of the septum there are right and left vesicular-nasal cartilages. The size and shape of the nose, the configuration of the nostrils are very variable.

Nasal cavity. Often near the anterior nasal awn in the mucosa there is a blind canalic - vomerous-nasal (Jacobson) organ. This organ goes up and back, rudimentary, is the homologue of the Jacobson organ of vertebrates. Behind and below the opening of the Jacobson organ, there is sometimes an opening leading to a blindly closed incisive (stenon) duct. It is in the incisive canal and is a rudimentary formation. The septum of the nose is rejected 70% of the time to the right or to the left. Expression of nasal concha, depth of nasal passages vary. Often behind the semilunar crevice there is an additional opening communicating the maxillary sinus with a medium nasal passage.

Larynx. Cartilages of the larynx in different people (elderly and old) vary in the degree of their calcification. The configuration, cartilage dimensions, have significant individual differences. Often the upper horns are absent in the thyroid cartilage, there is a one-sided or bilateral opening with a diameter of 1-6 mm in its plate. The cricoid cartilage sometimes has an additional tubercle located at the lower edge of its arch (marginal denticle), the grain-shaped cartilages may be absent, doubled or enlarged in size. Sometimes there are no puststechnitovidnye joints of the larynx. Mobility in the joints of the larynx is variable, their ligaments are expressed in varying degrees. The muscles of the larynx are most variable. In 10% there is a scytotracheal muscle, in 10% - perstnetraealnaya and in 3% - an unpaired transverse thyroid muscle. Very rarely there is a lateral epiglotti-thyroid muscle and a muscle that lifts the thyroid gland. In 20% of cases there is perstnenadgortan muscle, in 9% - muscle, lowering the arytenoid cartilages. Often (about 16%) there are additional tufts of the scapular muscle. In 22%, the lateral plateau muscle is absent. In the anterior half of the guttural ventricle, from one or both sides there may be a small notch - a laryngeal appendice (appendix), which has a variable shape and size.

Trachea. Variable length, width of the trachea, the number of cartilages in its walls (from 12 to 22). The shape of the cartilage often has individual characteristics. It is possible to separate the trachea into 3 main bronchi (trifurcation of the trachea), sometimes congenital fistulas of the trachea, messages with the esophagus are observed. Rarely, between the neck of the thyroid and the trachea, there is a scrapedotracheal bag. Rarely, such a bag is located between the aorta and the trachea (aortotracheal bag).

Lungs. Lungs vary in shape and size. Often there are additional shares of the right and left lungs (up to 6 lobes in the lung). Sometimes the tops of the lungs receive independent bronchuses, departing from the main bronchi. It is extremely rare in the presence of defects of the diaphragm, the displacement of additional lobes into the abdominal cavity is possible. Individually, the degree of development of the intrapulmonary connective tissue, the number of acini and their constituent components vary.

Pleura. The depth and severity of pleural sinuses varies individually. There are often spikes in the pleural cavity between the parietal and visceral pleural sheets. In 7% of cases, the right and left mediastinal pleura in the anterior mediastinum region are closed in some distance behind the sternum, forming a mesenteric mesenteria (mesocardium).

Mediastinum. Sometimes the mediastinum is narrow or unusually wide, which is associated with the configuration of the chest. The topography of the thoracic and abdominal cavities can be dramatically changed up to the opposite of their normal position (full or partial).