[Intraoperative Navigation System during Thoracoscopic Segmentectomy for Non-palpable Pulmonary Tumors;Infrared Thoracoscopy (IRT)-Indocyanine Green (ICG) and Intraoperative Computed Tomography(CT)-assisted Method].

OBJECTIVES: Recently, the use of video-assisted thoracoscopic surgery (VATS) segmentectomy for pulmonary malignancies has increased. For non-palpable lesions, securing a sufficient surgical margin is more likely to be uncertain. The purpose of this study was to evaluate the usefulness of our intraoperative navigation system in combination with the infrared thoracoscopy (IRT)-indocyanine green (ICG) method and intraoperative computed tomography (CT) during VATS segmentectomy for non-palpable pulmonary malignancies. METHODS: This study involved 12 consecutive patients who underwent both IRT-ICG and intraoperative CT-assisted thoracoscopic segmentectomy. Identification of the intersegmental line on the visceral pleura was visualized using IRT-ICG. The intersegmental line was marked by clipping, and intraoperative CT scan was performed under bilateral lung ventilation. The intraoperative CT images were used by the surgeons to confirm the correct anatomic segmental border and to secure a sufficient resection margin. RESULTS: A well-defined intersegmental line was observed in 83.3% of the patients. The rate of concordance between 3-dimensional (3D)-CT images reconstructed from intraoperative CT and preoperative simulation 3D-CT imaging was 91.7%. The mean surgical margin assessed on gross examination by the pathologist was 22.3 ± 4.5 mm. Complete resection was achieved in all patients using this approach. CONCLUSIONS: Imaging support including preoperative simulation, IRT-ICG and intraoperative CT enables surgeons to perform definitive VATS segmentectomy for non-palpable lesions.

[Adenocarcinoma with cavity formation caused by check valve mechanism].

A 63-year-old male who has a chief complaint of dyspnea on effort was admitted to our hospital because of abnormal chest computed tomography (CT). Chest CT showed a thin-walled cavity in the left lower lung that was 40 mm in diameter, and local high density shadow near the cavity. The tumor was resected and diagnosed as adenocarcinoma. The pathogenesis of the thin-wlled cavity formation in this case was considered to be caused by check valve mechanism.

Perpendicular implantation of porcine trachea extracellular matrix for enhanced xenogeneic scaffold surface epithelialization in a canine model.

Objective: The availability of clinically applied medical materials in thoracic surgery remains insufficient, especially materials for treating tracheal defects. Herein, the potential of porcine extracellular matrix (P-ECM) as a new airway reconstruction material was explored by xenotransplanting it into a canine trachea. Methods: P-ECM was first transplanted into the buttocks of Narc Beagle dogs (n = 3) and its overall immuno-induced effects were evaluated. Subsequently, nine dogs underwent surgery to create a tracheal defect that was 1 × 2 cm. In group A, the P-ECM was implanted parallel to the tracheal axis (n = 3), whereas in group B the P-ECM was implanted perpendicular to the tracheal axis (n = 6). The grafts were periodically observed by bronchoscopy and evaluated postoperatively at 1 and 3 months through macroscopic and microscopic examinations. Immunosuppressants were not administered. Statistical evaluation was performed for Bronchoscopic stenosis rate, graft epithelialization rate, shrinkage rate and ECM live-implantation rate. Results: No sign of P-ECM rejection was observed after its implantation in the buttocks. Bronchoscopic findings showed no improvement concerning stenosis in group A until 3 months after surgery; epithelialization of the graft site was not evident, and the ECM site appeared scarred and faded. In contrast, stenosis gradually improved in group B, with continuous epithelium within the host tissues and P-ECM. Histologically, the graft site contracted longitudinally and no epithelialization was observed in group A, whereas full epithelialization was observed on the P-ECM in group B. No sign of cartilage regeneration was confirmed in both groups. No statistically significant differences were found in bronchoscopic stenosis rate, shrinkage rate and ECM live-implantation rate, but graft epithelialization rate showed a statistically significant difference (G-A; sporadic (25%) 3, vs. G-B; full covered (100%) 3; p = 0.047). Conclusions: P-ECM can support full re-epithelialization without chondrocyte regeneration, with perpendicular implantation facilitating epithelialization of the ECM. Our results showed that our decellularized tracheal matrix holds clinical potential as a biological xenogeneic material for airway defect repair.