WW »74 WL: 43

Figure 1 (Continued) (J) The medial basal segmental artery, RLL. This is commonly the first branch of the basal artery, sometimes arising in combination with the anterior basal segmental artery or other basal segmental arteries. (K) The anterior, lateral, and posterior segmental arteries, RLL. These are variable in their origins and branching patterns.

Figure 1 (Continued) (L) The lateral and posterior basal segmental arteries, LLL. These may arise, as in this case, from a common trunk or in multiple other configurations.

difference, the arterial branching pattern on the left is quite similar to that on the right. However, there tend to be more separate arteries on the left than the right, with ''scattering of branches along the course of the main artery'' [19].

Left Upper Lobe

Either single or multiple branches arising from the ''pars anterior'' of the left pulmonary artery supply the anterior segment of the left upper lobe (Fig. 1C). Additional branches may arise from this anterior portion and supply portions of the apical and/or lingular segments. Following these branches, apical and posterior arteries usually arise from the superior aspect of the arching left pulmonary artery, and, unlike the apicoposterior segmental bronchus, which usually has a common origin, these two arteries most commonly arise separately (Figs. 1A and 1B).

Interlobar Segment

In contrast to the right side, on the left, the arterial supply to the superior segment of the lower lobe usually arises above the level of the lingular arteries

(Figs. 1E and 1F). Both the superior segmental arteries and the lingular arteries may each arise as a single trunk or as two separate arteries.

Basal Segments

As on the right, the pars basalis or basal trunk gives off arteries to the basal segments on the left. Just as there is usually a single left anteromedial basal segmental bronchus, there is usually a single anteromedial segmental artery (Fig. 1I). However, in about half of cases, the artery to the lateral basal segment arises from a common trunk with this anteromedial branch, separate from a single branch to the posterior basal segment. In the other half of cases, the lateral basal segmental artery arises from a common trunk with the posterior basal segmental branch (Fig. 1L) or in other configurations.

0 0

Post a comment