Three-dimensional imaging anatomical research and clinical implications of V d in the left upper lung.

Background: To investigate the distribution pattern of V d in the left superior pulmonary vein and its clinical significance.

Methods: A retrospective analysis was conducted using three-dimensional computed tomographic bronchography and angiography (3D-CTBA) data from 500 lung cancer patients. Statistical analyses were performed to evaluate the incidence and drainage patterns of the three sub-branches of V d, namely V d1, V d2 and V d3. Furthermore, clinical data from 10 patients' lesions involving V d were reviewed to illustrate the impact of adjacency to V d on the surgical approach.

Results: The incidences of V d1, V d2 and V d3 were 100%, 76.4% and 100% respectively. The relative interlobar distribution sizes of B a and B c and the left upper division (LUD) vein type influenced the incidence of V d2 (p < 0.05; p < 0.001). V d2 predominantly occurred in B a = B c and B c > B a patterns. V d2 was entirely absent in the B a > B c pattern. V d2 exhibited a higher incidence in both the central vein (CV) type and the noncentral vein (NCV) type when compared to the semi-central vein (SCV) type (100% vs. 100% vs. 64.8%). The most prevalent venous drainage pattern was the three sub-branches of V d constituting a major trunk to drain (41.2%). All 10 cases with lesions involving V d successfully underwent sublobar resection with no complications, and the surgical margin was ≥2 cm.

Conclusions: The three sub-branches of V d exhibit a high incidence with diverse distribution patterns, yet a discernible pattern exists. For inter- or multi-intersegmental nodules involving V d, combined segmentectomy and subsegmentectomy or combined subsegmentectomy can ensure the safe margin.