2000 Volume 14 Issue 5 Pages 591-601
We dissected in detail the intrapulmonary bronchi and vessels of 62 human lung specimens with aberrant lobulation, especially those showing the right posterior pulmonary lobe (PPL, 25 specimens) or left upper anterior fissure (LUAF, 22 specimens).
The LUAF-type aberrant fissure corresponded to the border between S3 and S4 in 59.1% of the entire 22 specimens. In other words, this aberrant lobe comprised either the entire lingual lobe or a smaller area. The upper division bronchus, B1+2+ B3, was longer than that in the control group, and A4 and A5 frequently formed a single trunk originating at the interlobar surface. Therefore, segmentectomy along this aberrant fissure, if conducted, would appear to be easier than usual. However, the aberrant lobe was not drained by a single vein, but often by two veins. Moreover, one of these drainage veins did not usually enter the superior pulmonary vein, but merged with the inferior vein. Thus, very careful treatment of veins might be necessary in spite of the favorable situation described above.
The right PPL-type aberrant fissure corresponded to the border between S6 and other inferior segments in 92.0% of the entire 25 specimens. In the other cases, a fissure divided S8. Usually, B7 was not independent but formed a common trunk with B* or B8. V6 did not comprise a single vein but two veins, this situation being more frequent than in the control group.rNotably, in combination with the right PPL, abnormal communicating vessels (2-4mm in diameter), which have never been reported in normal specimens, were sometimes (36% of the right PPL specimens) observed running between A6 (or V6) and A2 (or V2), and A3, as well as between the former and other inferior segmental vessels. Accordingly, lobectomy or segmentectomy involving the PPL would seem to require thorough observation of the related vessels during surgery at both the interlobar and mediastinal surfaces. Thus, the aberrant pulmonary fissure, if evident, may be a good landmark for separation during surgery, although there is an associated pitfall.
