Left anterior segmental bronchus (B3)

Bronchus segmentalis anterior

RespiratoryOrgansThoraxLeft side

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What it is
Segmental (tertiary) bronchus B3, supplying the anterior bronchopulmonary segment of the left upper lobe.
Function
Conducts air to one bronchopulmonary segment, a pyramidal unit of lung with its own bronchus and segmental artery.
Size
About 4 cm long and 4–6 mm in diameter; its wall holds irregular cartilage plates.
Clinical note
Because each segment has its own airway and blood supply, a diseased segment can be removed on its own (segmentectomy).

Nearby respiratory structures Bronchial tree (subsegmental bronchi), Left apicoposterior segmental bronchus (B1+2), Left inferior lingular segmental bronchus (B5), Left lower lobe bronchus, Left lung, upper lobe (with lingula), Left main bronchus, Left superior lingular segmental bronchus (B4), Left upper lobe bronchus, Parietal pleura, Visceral pleura