X-ray anatomy of the trachea, bronchi, lungs and pleura

On the roentgenogram, the trachea and the main bronchi are visible due to the presence of air in them - a trachea in the form of a light cylindrical formation against the background of the shadow of the spine. The main bronchi form light strips above the shadow of the heart. Investigation of the remaining parts of the bronchial tree (bronchography) is possible after the introduction of a contrast agent into the trachea and bronchi. The lungs of a living person with fluoroscopy or radiography are visible against the background of the chest in the form of air pulmonary fields (right and left), separated from each other by an intense median shadow formed by the spine, sternum, left heart and large vessels protruding to the left. On the pulmonary fields, the shadows of the clavicles (above) and the ribs are layered. In the intervals between the ribs, a net-shaped pulmonary pattern is visible, on which spots and cords are stratified - shadows from the bronchi and blood vessels of the lung. In the region of the roots of the lungs (at the level of the anterior ends of the II-V ribs), shadows from larger bronchi and vessels with thicker walls are more pronounced. When X-ray examination during inspiration, the pulmonary fields are seen better, and the pulmonary pattern is seen more clearly. With the help of tomography (layered radiography), you can get pictures of separate deep layers of the lung with its bronchi and vessels.

Innervation: branches of the vagus nerve and sympathetic trunk, forming a pulmonary plexus in the area of the root of each lung. The branches of the pulmonary plexus around the bronchi and vessels penetrate into the thickness of the lung, where they form the peribronchial plexus.

Blood supply: arterial blood to feed the lung tissue, including bronchi, enters the bronchial arteries (from the thoracic part of the aorta). Bronchial veins are inflows of pulmonary veins, unpaired and semi-unpaired veins. Venous blood enters the lungs through the pulmonary arteries. Enriching with oxygen during gas exchange, losing carbon dioxide, the blood turns into an arterial one. Arterial blood through the pulmonary veins flow into the left atrium.

Outflow of lymph: bronchopulmonary, lower and upper tracheobronchial lymph nodes.

The first division of the lung into lobes was developed by the Swiss anatomist Aeby (1880). The first mention of the segment of the lung (as a term) is found in the work of Kramer and Glass (1932), which the segment of the lung, which is part of the lobe and ventilated by a constant segmental bronchus, is equipped with a corresponding branch of the pulmonary artery. The veins that divert blood from the segments pass in the connective tissue partitions between the adjacent segments. Segments of the lung have the form of an irregular truncated cone, the apex of which is directed toward the root, and the base to the surface of the lung, and covered with a visceral pleura.

Currently, among the clinicians, the classification and use of pulmonary segments, approved by the Congress of Otolaryngologists and the Society of Breast Disease Specialists in London in 1949, was most widely used and disseminated. The development of this unified international nomenclature was promoted by the established special committee composed of the largest specialists in the anatomy of the lungs and bronchology (Jackson, Brock, Sulya, etc.). This classification was supplemented at the VI International Congress of Anatomists in Paris (1955) and the VIII All-Union Congress of Anatomists, Histology and Embryology in Tashkent (1974).

Each lung is divided into parts by means of intersecting slits, into which the visceral pleura penetrates covering the interlobar surfaces of the lung, but does not reach 1 -2 cm to the root of the lung.

It is known that the right lung consists of 3 lobes, the left lobe consists of 2 lobes. In the right lung usually 1 0 segments are distinguished, in the left - 8.

The upper lobe of the right lung is divided into 3 segments: apical (1), posterior (2), anterior (3). In the upper lobe, both in adults and in children, pneumonia, tuberculous infiltrates and caverns are often localized.

In the middle lobe, 2 segments are distinguished: lateral (4) and medial (5).

The lower lobe is divided into 5 segments: the upper segment, or the Nelson's bronchus (6), the medobasal, or the cardiac (7), anterior basal (8), lateral-basal (9), posterolateral (10). In S6, cancer, pneumonia and tubercular caverns are often localized. S8, S9 and S10 are often affected by bronchiectasis and abscesses.

In the upper lobe of the left lung, four segments are distinguished: apical-posterior (1 + 2), anterior (3), upper reed (4), lower reed (5). When X-ray study accurately draw the boundaries between the two ligulate segments is difficult, but the pathological process quite often captures both segments.

The lower lobe of the left lung contains 4 segments: the upper segment (6), the anterior basal (8), the lateral basal (9), the posterior basal (10).

However, this classification is not without its shortcomings, since it does not take into account the concepts of "lung zone" and "zonal bronchus" proposed by IO. Lerner (1948), BE Lindberg (1948), Yu.N. Sokolov and L.S. Rosenstrauch (1958). According to their classification, 4 zones are allocated in each lung. Right: the upper lobe is the upper zone, the middle lobe is the anterior, the VI segment is the posterior (or Fauchler's tip), the basal segments are the lower zone. Left: apical-posterior and anterior segments - the upper juni, the ligula bronchi - the anterior zone, the sixth segment - the posterior region, the basal segments - the lower zone.