Anatomy of the trachea and broncheal tree By; Dr. Eman Abdelghany Assistant Prof. of Anatomy & Embryology Al-Qassim university

Anatomy of the trachea 10 cm : 2 cm Length: 10 cm Width: 2 cm as a continuation of larynx, at lower border of cricoid cartilage Begins: as a continuation of larynx, at lower border of cricoid cartilage (C6). Ends: by dividing into two main bronchi opposite the disc between 4 th & 5 th thoracic vertebrae. It lies in midline of neck in front of esophagus and behind thyroid gland. Upper1\2 in the neck called cervical part, and Lower 1\2 in the thorax(in superior mediastinum) called thoracic part, It shows slight deviation to the right. Carina Y shaped last ring

Trachea Trachialis muscle

Anatomy of the trachea continue, completed by trachealis muscle posteriorly incomplete cartilaginous rings (C –shaped)- completed by trachealis muscle posteriorly. Becomes intra-thoracic at 6 th cartilaginous ring Carina The last tracheal ring is Y- shaped called the carina. The Carina is the site of branching to left and right primary bronchi, at the tracheal bifurcation. The posterior wall is trachealis muscle which, allows esophageal expansion during deglutition

Bronchial Tree A highly branched system, The air-conducting passages originate from the left and right primary bronchi. Progressively branch into narrower tubes as they diverge throughout the lungs before terminating into terminal bronchioles. Primary bronchi. -Incomplete rings of hyaline cartilage ensure that they remain open. They enter the hilum of each lung. Right primary bronchus is, shorter, wider, and more vertically oriented than the left primary bronchus. Foreign particles are more likely to lodge in the right primary bronchus

Bronchial Tree continue, Secondary bronchi (or lobar bronchi) –Branch of primary bronchus –left lung: 2 lobes 2 secondary bronchi –Right lung 3 lobes 3 secondary bronchi. Tertiary bronchi (or segmental bronchi) –Branch of secondary bronchi –left lung is supplied by 8 to 10 tertiary bronchi. –right lung is supplied by 10 tertiary bronchi –supply a part of the lung called a bronchopulmonary segment.

Broncho pulmonary segments: -well defined sectors of lung. -Each is aerated by segmental bronchus, separate branch of pulmonary artery.veins are intersegmental. -each segment is surrounded by connective tissue and forms a separate respiratory unit. -shape: pyramidal with apex at the hilum and the base towards surface of lung.

+ Medial basal segment 10 segments

Arise by common stem Med. Basal,small. May arise by common stem with ant. basal

Nasal Cavity Nose Mouth Bronchus Bronchiole Alveolus Diaphragm Throat (pharynx) Windpipe (Trachea) Left lungs Ribs

So Take a Deep Breath and Go Home The End