With the widespread adoption of low-dose CT screening and the extensive application of high-resolution CT, the detection rate of sub-centimeter lung nodules has significantly increased. How to scientifically manage these nodules while avoiding overtreatment and diagnostic delays has become an important clinical issue. Among them, lung nodules with a consolidation tumor ratio less than 0.25, dominated by ground-glass shadows, are particularly worthy of attention. The therapeutic challenge for this group is how to achieve precise and complete resection of nodules during surgery while maximizing the preservation of the patient's lung function. The "watershed topography map" is a new technology based on big data and artificial intelligence algorithms. This method uses Dicom data from conventional dose CT scans, combined with microscopic (22-24 levels) capillary network anatomical watershed features, to generate high-precision simulated natural segmentation planes of lung sub-segments through specific textures and forms. This technology forms fluorescent watershed boundaries on the lung surface, which highly fit the actual lung anatomical structure. By analyzing the adjacent relationship between the nodule and the watershed boundary, real-time, visually accurate positioning of the nodule can be achieved. This innovative technology provides a new solution for the intraoperative positioning and resection of lung nodules. This consensus was led by four major domestic societies, jointly with expert teams in related fields, oriented to clinical practical needs, referring to domestic and foreign guidelines and consensus, and finally formed after multiple rounds of consultation, discussion, and voting. The main content covers the theoretical basis of the "watershed topography map" technology, indications, operation procedures, surgical planning details, and postoperative evaluation standards, aiming to provide scientific guidance and exploration directions for clinical peers who are currently or plan to carry out lung nodule resection using the fluorescent microscope watershed analysis method.
ObjectiveTo compare the clinical effects of segmentectomy and lobectomy for ≤2 cm lung adenocarcinoma with micropapillary and solid subtype negative by intraoperative frozen sections.MethodsThe patients with adenocarcinoma who received segmentectomy or lobectomy in multicenter from June 2020 to March 2021 were included. They were divided into two groups according to a random number table, including a segmentectomy group (n=119, 44 males and 75 females with an average age of 56.6±8.9 years) and a lobectomy group (n=115, 43 males and 72 females with an average of 56.2±9.5 years). The clinical data of the patients were analyzed.ResultsThere was no significant difference in the baseline data between the two groups (P>0.05). No perioperative death was found. There was no statistical difference in the operation time (111.2±30.0 min vs. 107.3±34.3 min), blood loss (54.2±83.5 mL vs. 40.0±16.4 mL), drainage duration (2.8±0.6 d vs. 2.6±0.6 d), hospital stay time (3.9±2.3 d vs. 3.7±1.1 d) or pathology staging (P>0.05) between the two groups. The postoperative pulmonary function analysis revealed that the mean decreased values of forced vital capacity and forced expiratory volume in one second percent predicted in the segmentectomy group were significantly better than those in the lobectomy group (0.2±0.3 L vs. 0.4±0.3 L, P=0.005; 0.3%±8.1% vs. 2.9%±7.4%, P=0.041).ConclusionSegmentectomy is effective in protecting lungs function, which is expected to improve life quality of patients.