Posterior Basal Segmental Artery of the Left Lung

Description

Arising from the left pulmonary artery, the posterior basal segmental artery courses inferiorly and posteriorly into the lower lobe to supply the posterior basal bronchopulmonary segment (S10). Within the hilum it lies in close company with the segmental bronchus and segmental pulmonary veins, then divides into progressively smaller segmental branches and arterioles that track alongside the bronchial tree toward the peripheral acini. More medially and superiorly, the heart and great vessels sit anterior to the left main bronchus and pulmonary trunk, while the trachea remains superior in the mediastinum. Segmental pulmonary arterial anatomy matters when you need to localize disease to a bronchopulmonary segment and when you want to remove that segment without sacrificing the rest of the lobe. For left lower lobe segmentectomy, S10 dissection hinges on correctly identifying the posterior basal arterial branch among adjacent basal branches, since anatomic variants and early bifurcation can turn a straightforward stapling step into uncontrolled bleeding. It is a surgical problem. Educators will find this view useful when teaching pulmonary segmental anatomy alongside bronchoscopy maps and when explaining why a segmental pneumonia, infarct after pulmonary embolism, or focal arteriovenous malformation often respects segmental boundaries. It also suits thoracic surgery atlases, radiology primers correlating CT angiography with lower-lobe branching patterns, and cardiopulmonary texts that contrast pulmonary arteries (oxygen-poor blood) with systemic coronary vessels (oxygen-rich blood) around the heart. Anatomical accuracy verified by SciePro's Medical Advisory Board.