A lung segment is a subdivision of a lung lobe, defined by the
segmental bronchi and the corresponding segmental arteries. Each
lung is divided into lobes (three in the right lung and two in the left),
and these lobes are further segmented into bronchopulmonary
segments. There are 10 segments in the right lung and 8-10
segments in the left lung, each with its own airway (bronchus),
blood supply (artery), and lymphatic drainage, separated from
adjacent segments by connective tissue. Understanding lung
segments is crucial in clinical practice, especially in surgical
procedures (like segmentectomy) and bronchoscopy, as well as in
diagnosing and treating localized lung diseases such as pneumonia,
tumors, or bronchiectasis. Imaging studies, such as CT scans, often
reference specific segments to accurately describe the location of
abnormalities, aiding in precise diagnosis and treatment planning.