Читать книгу Atlas of Endoscopic Ultrasonography - Группа авторов - Страница 28

Extratracheal anatomy is similar to extraesophageal anatomy and many of the structures seen in the extratracheal spaces are the same as what is seen in the extraesophageal spaces. The endoluminal views of the trachea are oriented so that the membranous trachea is inferior and is splayed wider than the cartilaginous trachea at the level of the carina, putting the right mainstem bronchus (RMB) to the right and the left mainstem bronchus (LMB) to the left (Figure 1.9). As one goes right the bronchus immediately branches superiorly towards the right upper lobe (RUL), and continues straight as bronchus intermedius (BI) (Figure 1.10), which then branches towards the right middle lobe (RML) and right lower lobe (RLL) of the lung (Figure 1.11).

Going left from the carina, one goes down the relatively long left mainstem bronchus until it branches towards the left upper lobe (LUL) and left lower lobe (LLL) of the lung (Figure 1.12). An overview of the bronchial tree is shown in Figure 1.13.

Video 1.13 starts with the cervical trachea. All images are in a linear array orientation as endobronchial ultrasound (EBUS) is exclusively linear. The esophagus is inferior and the brachiocephalic artery and vein are superior. The video begins with rotation of the image plane. The superior part of the plane moves left and the inferior part moves right. This moves the esophagus out of view and brings the left subclavian artery and left carotid artery into the inferior part of the image. Eventually, the esophagus is seen in the superior part of the image and, with continued motion, the esophagus again appears inferior to the trachea. At this point, the image plane moves caudally to the carina. The right pulmonary artery, brachiocephalic artery (BA), and left brachiocephalic vein (LBV) are labeled. The plane is again rotated to splay the right (RMB) and left (LMB) mainstem bronchi apart. The plane is then moved to better visualize the right mainstem bronchus, showing the branch to the right upper lobe (RUL), the azygos arch (AzArch), the bronchus intermedius (BI). This same plane shows the relation of the aortic arch (AoArch) and left pulmonary artery to the left mainstem bronchus (LMB). As the plane goes down the right mainstem bronchus/bronchus intermedius (RMB) towards its next bifurcation, the azygos arch (AzAr), right pulmonary artery (RPA), and right pulmonary vein (RPV) are shown.

Figure 1.9 Endobronchial view of the carina, showing the right (RMB) and left (LMB) mainstem bronchi.

Figure 1.10 Endobronchial view of the first branch of the right mainstem bronchus towards the right upper lobe (RUL) and the bronchus intermedius (BI).

Figure 1.11 Endobronchial view of the bifurcation of the bronchus intermedius towards the right middle lobe (RML) and the right lower lobe (RLL).

Figure 1.12 Endobronchial view of bifurcation of the left mainstem bronchus towards the left upper lobe (LUL) and left lower lobe (LLL).

The plane is brought back to the carina to visualize the left mainstem bronchus (LMB), and the azygos arch (AzAr), aortic arch (AoAr), left pulmonary artery (LPA), and vein (LPV) are identified. The branching to the left upper lobe (LUL) and left lower lobe (LLL) are shown, and the aorta (Ao) and left pulmonary artery are labeled.

Figure 1.13 A Visible Human Model of the bronchial tree.