Three-dimensional imaging anatomical research and clinical implications of V^{1 +2}d in the left upper lung

Background: To investigate the distribution pattern of V(1+2)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(1+2)d, namely V(1+2)d(1), V(1+2)d(2) and V(1+2)d3. Furthermore, clinical data from 10 patients' lesions involving V(1+2)d were reviewed to illustrate the impact of adjacency to V(1+2)d on the surgical approach.Results: The incidences of V(1+2)d1, V(1+2)d(2) and V(1+2)d3 were 100%, 76.4% and 100% respectively. The relative interlobar distribution sizes of B3a and B(1+2)c and the left upper division (LUD) vein type influenced the incidence of V(1+2)d2 (p < 0.05; p < 0.001). V(1+2)d2 predominantly occurred in B3a = B(1+2)c and B1+2c > B3a patterns. V(1+2)d2 was entirely absent in the B3a > B(1+2)c pattern. V(1+2)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(1+2)d constituting a major trunk to drain (41.2%). All 10 cases with lesions involving V(1+2)d successfully underwent sublobar resection with no complications, and the surgical margin was >= 2 cm.Conclusion: The three sub-branches of V(1+2)d exhibit a high incidence with diverse distribution patterns, yet a discernible pattern exists. For inter- or multi-intersegmental nodules involving V(1+2)d, combined segmentectomy and subsegmentectomy or combined subsegmentectomy can ensure the safe margin.