Inferior lobar artery of left lung
Arteria lobaris inferior pulmonis sinistri
- Related terms: Inferior lobar arteries
Definition
The inferior lobar artery of the left lung is a branch of the left pulmonary artery that supplies the lower lobe of the left lung. It arises after the left pulmonary artery enters the hilum of the left lung and gives off the superior lobar branches. The inferior lobar artery descends posterolaterally along the oblique fissure and subsequently divides into segmental branches that correspond to the bronchopulmonary segments of the left lower lobe.
The inferior lobar artery of left lung is often divided into two parts:
The left interlobar artery that arises from the LPA after the origin of the branches for upper lobes. It gives branches for the lingula and the superior segment of the inferior left lobe.
The common basal trunk (basal part; pars basalis), that begins caudal to the origin of the superior segmental artery and gives branches for the basal part of the left lower lobe.
The inferior lobar artery typically gives rise to the following segmental arteries:
Clinical relevance:
The inferior lobar artery is an important landmark in thoracic imaging, particularly on CT pulmonary angiography, where it is evaluated for the presence of pulmonary embolism. Thrombus within this vessel constitutes a lobar-level pulmonary embolism.
Knowledge of its anatomy is essential during left lower lobectomy, where the segmental branches of the inferior lobar artery must be individually identified, ligated, and divided.
Enlargement of the inferior lobar artery on chest radiography (greater than 16 mm in diameter on the left) can be a sign of pulmonary arterial hypertension.
Relationship to surrounding structures:
The inferior lobar artery courses in close proximity to the left lower lobe bronchus, running anterolateral to it within the hilum. It is surrounded by peribronchial connective tissue and hilar lymph nodes, which are relevant in the staging of lung malignancies.
