胸部正常影像HR__培训课件.ppt

The posterior basal segment (S10) as its name implies occupies the posterior most and inferior most portion of the right lower lobe. As such, it can be best remembered as the pulmonary segment which occupies most of the posterior costophrenic gutter. S10 also comprises a large portion of the posteromedial border of the right lower lobe and is the segment which is located immediately inferior to S6. S10 characteristically tends to be the largest segment of the right lower lobe. Left Lung Segments (S1+2) represents a combination of the two separate (apical and posterior) segments seen on the right upper lobe. It is referred to as the apical posterior segment. Combined, S1+2 anatomically is similar in shape to the two segments on the right. The S3 or anterior segment also is similar to the right S3 segment, having a large area directed anteriorly. The superior lingular segment (S4) is positioned immediately inferior to S3 and is directly above the inferior lingular segment (S5). Both lingular segments have their greatest area directed anteriorly and inferiorly. Additionally, S4 tends to have more area directed laterally while S5 has more area directed medially, abutting the mediastinum. Both segments extend anteroinferiorly to reach the ventral surface of the left hemidiaphragm, and hence border a large portion of the anteroinferior surface of the major fissure. Forming the remainder of the interlobar surface is the superior segment (S6). S6 is identical to its counterpart on the right. The left lower lobe segmental architecture is similar to that of the right lower lobe, however because the anterior and medial basal segments share a common bronchial supply, these two segments are characteristically combined, forming an anterior medial basal segment (S8). Therefore, the anterior segment is combined with the medial segment but may be denoted by SX7. The anterior medial basal segment is