Prediction of visceral pleural invasion of clinical stage I lung adenocarcinoma using thoracoscopic images and deep learning.

PURPOSE: To develop deep learning models using thoracoscopic images to identify visceral pleural invasion (VPI) in patients with clinical stage I lung adenocarcinoma, and to verify if these models can be applied clinically. METHODS: Two deep learning models, one based on a convolutional neural network (CNN) and the other based on a vision transformer (ViT), were applied and trained via 463 images (VPI negative: 269 images, VPI positive: 194 images) captured from surgical videos of 81 patients. Model performances were validated via an independent test dataset containing 46 images (VPI negative: 28 images, VPI positive: 18 images) from 46 test patients. RESULTS: The areas under the receiver operating characteristic curves of the CNN-based and ViT-based models were 0.77 and 0.84 (p = 0.304), respectively. The accuracy, sensitivity, specificity, and positive and negative predictive values were 73.91, 83.33, 67.86, 62.50, and 86.36% for the CNN-based model and 78.26, 77.78, 78.57, 70.00, and 84.62% for the ViT-based model, respectively. These models' diagnostic abilities were comparable to those of board-certified thoracic surgeons and tended to be superior to those of non-board-certified thoracic surgeons. CONCLUSION: The deep learning model systems can be utilized in clinical applications via data expansion.

Congenital vascular ring.

A vascular ring is a rare congenital cardiovascular anomaly, which encircles and compresses the trachea or esophagus, or both. In this review we discuss the pathophysiology, theoretical embryopathogenesis, diagnostic modalities, and surgical treatment of the different types of vascular ring. Knowledge of the normal embryonic development of the aortic arch and related structures is important for understanding and classifying the various forms of vascular ring. The development of a vascular ring begins with the embryonic aortic arch system. The persistence, involution, or regression of the arches determines the multiple variations of vascular ring. With the development of new technologies, multi-detector computed tomography (MDCT) has become a good diagnostic modality for pre- and postoperative evaluation. MDCT provides an excellent image of aortic arch abnormalities and the related anatomy, as well as the tracheal pathology. For patients with symptoms, surgical division of the vascular ring usually achieves excellent outcomes with marked resolution of symptoms and a low risk of morbidity and mortality. Symptomatic vascular rings require early surgical intervention to prevent prolonged vascular compression of the airway and serious complications.

Sternum-splitting anterior approach following posterior decompression and fusion in patients with massive ossification of the posterior longitudinal ligament in the upper thoracic spine: report of 2 cases and literature review.

PURPOSE: Anterior approach to the upper thoracic spine is difficult. It is important for spine surgeons to know the indication and the effect of anterior decompression for upper thoracic lesions and also to recognize the complications which are related to the approach with sternotomy. We present two patients for whom we took the sternum-splitting anterior approach for thoracic ossification of the posterior longitudinal ligament (OPLL) following posterior decompression and fusion surgery; the clinical course and surgical outcome are discussed, with particular reference to complication avoidance and also we review the previous literature. METHODS: We present two cases with severe upper thoracic OPLL. The maximum occupying ratio of OPLL against the spinal canal was more than 80% in both cases. Posterior decompression and fusion were not effective and, therefore, anterior surgery with sternotomy was carried out. RESULTS: Cerebrospinal fluid leak was encountered with the removal of OPLL using the anterior approach. Subsequently, a polyglycolic acid sheet was used to cover the defect in the dura matter; a thoracic drainage system with a continuous suction unit was positioned at the surgical wound to avoid fluid retention in the mediastinum. In addition, we facilitated spinal drainage from the lumbar level. These procedures resulted in no complication caused by fluid retention in the mediastinum. CONCLUSION: Both a safe surgical approach and preventive measures to alleviate postoperative complications are mandatory in difficult cases with thoracic OPLL.

[A Retrospective Study Analyzing the Clinical Course of Patients with Non-Small Cell Lung Cancer Receiving Local or Systemic Therapy after Post-Operative Recurrence].

BACKGROUND: While systemic therapy is one of the therapeutic options available for post-operative recurrence of non-small cell lung cancer, efficacy of local therapy for locoregional recurrence or limited metastatic lesions has also been reported. OBJECTIVE: We aimed to evaluate the clinical course of patients with post-operative recurrence(locoregional or limited metastatic lesion)after receiving local or systemic therapy. METHODS: Clinical data were retrospectively analyzed and survival duration was compared using the logrank test. RESULTS: A total of 22 patients were included. Median progression-free survival in patients receiving local therapy, systemic chemotherapy, or a combination of both therapies was 15.1 months, 6.3 months, and 13 months, respectively. Two patients receiving treatment with EGFR-TKI did not show disease progression at 41.3 months and 45.8 months(p=0.265). Median overall survivals in patients receiving local therapy, systemic chemotherapy, or a combination of both therapies were 26.5 months, 20 months, and 37.9 months, respectively(p=0.510). After the treatment, 6 patients showed regrowth of the recurrent lesion, 8 patients showed remote metastases, and 2 patients showed both regrowth of the recurrent lesion and remote metastases. CONCLUSION: Patients who received treatment including local therapy showed longer survival duration, but statistical significance was not detected. Our study suggested that regrowth of the recurrent lesion and remote metastases can be equally observed after treatment.

Complete thoracoscopic diaphragm plication using carbon dioxide insufflation: report of a case.

Diaphragm plication has become the accepted treatment for major respiratory impairment caused by diaphragmatic eventration and paralysis. Various open and minimally invasive plication techniques have been described and while video-assisted thoracoscopic diaphragm plication appears to be a safe and effective alternative to open surgery, the workspace is limited. We describe how we performed complete thoracoscopic diaphragm plication using carbon dioxide (CO2) insufflation for a patient with unilateral diaphragmatic eventration. Using CO2 insufflation seems to dramatically improve the workspace.

Predictive factors of early autologous blood pleurodesis for postoperative air leak.

BACKGROUND: The usefulness of autologous blood pleurodesis for air leak after pulmonary resection is well known; however, factors predicting the therapeutic efficacy are poorly understood. Herein, we aimed to examine the predictors of early autologous blood pleurodesis for air leak following pulmonary resection. METHODS: Patients who underwent pulmonary resection and autologous blood pleurodesis with thrombin for postoperative air leak between January 2016 and October 2022 were retrospectively analyzed. Patients received 50-100 mL of autologous blood and 20,000 units of thrombin on postoperative days 1-4. If necessary, the same procedure or pleurodesis with other chemical agents was repeated until the air leak stopped. Patients were divided into single-dose and multiple-dose groups based on the number of times pleurodesis had occurred before the air leak stopped and were statistically analyzed. Logistic regression analysis was performed to identify predictors of treatment efficacy. RESULTS: Of the 922 patients who underwent pulmonary resection, 57 patients (6.2%) were included and divided into single-dose (n = 38) and multiple-dose (n = 19) groups. The amount of air leaks was identified as a significant predictor of multiple dosing, with a cutoff of 60 mL/min, in multivariate logistic regression analyses (odds ratio 1.13, 95% CI 1.03-1.24, p = 0.0065). The multiple-dose group showed a significantly higher recurrence of air leak (p = 0.0417). CONCLUSIONS: The amount of air leaks after pulmonary resection is the only significant factor predicting whether multiple autologous blood pleurodesis is required, and the recurrence rate of pneumothorax is significantly higher in such cases.

Early chest tube removal within 6 hours after thoracic surgery results in improved postoperative prognosis and no adverse effects.

Background: Advances in minimally invasive surgery and drainage systems have caused earlier chest-tube-removal. This retrospective study aimed to assess the safety of early chest tube removal using the institution's new criteria 6 hours after thoracic surgery. Methods: Elective thoracic surgery patients from 2017 to 2023 were reviewed for meeting or not meeting the newer institutional requirement for early chest tube removal; (I) no air leak detected under the digital drainage device observation; (II) no fluid drainage of ≥100 mL/h; (III) no ≥3 combined risks [male, chronic obstructive pulmonary disease (COPD), body mass index (BMI) of <18.5 kg/m2, severe pleural adhesion, upper lobe lobectomy, or left upper division segmentectomy]. The incidence of adverse events, including chest tube replacement, subcutaneous tube placement, and postoperative thoracentesis, were investigated for 1 month postoperatively. Perioperative outcomes and factors involved in conventional chest tube removal were also assessed. Results: Of the 942 patient charts reviewed, 244 (25.9%) met the criteria for chest tube removal within 6 hours postoperatively. This patient group did not experience adverse events. They also demonstrated shorter postoperative hospital stay (4 vs. 6 days, P<0.001), and lesser postoperative complications (7.4% vs. 25.6%, P<0.001) compared to those for whom early chest tube removal was not done. A correlation with thoracotomy, COPD, and steroid and/or immunosuppressant use was observed for patients in the conventional chest tube removal group. Conclusions: Early chest tube removal after 6 postoperative hours was deemed safe for a selected group of patients who met the criteria for early chest tube removal. This study would support the potential expansion of our early removal criteria.

Preoperative umeclidinium/vilanterol or tiotropium improves postoperative FEV1 in lung cancer patients with comorbid untreated chronic obstructive pulmonary disease.

Background: This study aimed to examine the effects of preoperative interventions in lung cancer patients with untreated chronic obstructive pulmonary disease (COPD). We evaluated the efficiency of preoperative interventions using tiotropium (TIO) or umeclidinium/vilanterol (UMEC/VI). Methods: We conducted a two-center retrospective study. Perioperative forced expiratory volume in 1 second (FEV1) was compared between a preoperative COPD intervention group and an untreated group. COPD therapeutic drugs were started 2 weeks before surgery and were continued until 3 months after surgery. Radical lobectomy was performed in patients with an FEV1 of ≥1.5 L. Results: A total of 92 patients were enrolled (untreated, 31 patients; intervention, 61 patients). In the intervention group, 45 (73.8%) patients were prescribed the UMEC/VI intervention and 16 (26.2%) received TIO. The intervention group showed a greater increase in FEV1 than the untreated group (FEV1: 120 vs. 0 mL, P=0.014). In the intervention group, the UMEC/VI group showed a greater increase in FEV1 than the TIO group (FEV1: 160 vs. 7 mL, P=0.0005). In 9 of 15 (60.0%) patients with an FEV1 of <1.5 L before intervention, FEV1 increased to ≥1.5 L after intervention. Postoperative FEV1 in the intervention group was similar to that before intervention, unlike in the untreated group (-0.05 vs. -0.25 mL, P=0.0026). Moreover, the FEV1 in the untreated group was similar to the preoperative predicted value, whereas that in the intervention group was significantly higher than the predicted value (+0.33 vs. +0.04 mL, P<0.0001). Conclusions: In lung cancer patients with untreated COPD, active preoperative intervention improved respiratory function, expanded treatment options, and maintained respiratory function to a degree that exceeded preoperative predictions.

A series of experiences with TissuePatch™ for alveolar air leak after pulmonary resection.

OBJECTIVES: Prolonged air leak after pulmonary resection strongly influences chest tube duration and hospitalization. This prospective study aimed to report a series of experiences with a synthetic sealant (TissuePatch™) and compare them with a combination covering method (polyglycolic acid sheet + fibrin glue) for air leaks after pulmonary surgery. METHODS: We included 51 patients (age: 20-89 years) who underwent lung resection. Patients who presented with alveolar air leak during the intraoperative water sealing test were randomly assigned to the TissuePatch™ or combination covering method groups. The chest tube was removed when there was no air leak over a period of 6 h, and no active bleeding under continuous monitoring using a digital drainage system. The chest tube duration was assessed, and various perioperative factors (such as the index of prolonged air leak score) were evaluated. RESULTS: Twenty (39.2%) patients developed intraoperative air leak; ten patients received TissuePatch™; and one patient who was receiving TissuePatch™ switched to the combination covering method because of broken TissuePatch™. The chest tube duration, index of prolonged air leak score, prolonged air leak, other complications, and postoperative hospitalization in both groups were similar. No TissuePatch™-related adverse events were reported. CONCLUSIONS: Results from the use of TissuePatch™ were almost similar to those associated with the use of combination covering method in preventing prolonged postoperative air leak after pulmonary resection. Randomized, double-arm studies are required to confirm the efficacy of TissuePatch™ observed during this study.

Factors affecting insulation failure in reusable surgical devices.

The purpose of this study was to investigate the associated factors of insulation failure (IF) in reusable endoscopic instruments. The insulation coating of reusable endoscopic instruments underwent routine visual checks, hand washing to remove visible stains, and mechanized sterilization. We recorded the cleaning number and usage period of all instruments. The instruments were tested for IF using a detector. IF was found in eight of 69 devices (11.6%). Examining by clinical specialty, we found IF in 4 of 28 gastrointestinal (14.3%), 3 of 20 gynecological (15.0%), 1 of 12 urological (8.3%), and none of the nine thoracic devices. The median distance from the tip to the damaged part was 5 cm (3-5 cm). In the IF and the intact groups, the period of use [7 years (6-8) versus 7 years (4-8), P = 0.90] and the number of cleanings [281 (261-323) versus 261 (179-320), P = 0.27] were not significantly different. The IF group included products of three different companies; however, six of the eight (75.0%) were from the same company. Cleaning methods and usage period have a lower impact on IF. The use of reusable forceps as a monopolar device was found to pose a higher risk, requiring regular assessments.

Experiences of novel cotton device for uniportal video-assisted thoracoscopic surgery: CS Two-Way HandleTM.

In Japan, cotton is commonly used in thoracic surgery for the gentle handling of organs as well as obtaining a good surgical field. While uniportal video-assisted thoracoscopic surgery is being recognized as a major surgical approach, use of cotton is not noted in this technique. Uniportal video-assisted thoracoscopic surgery needs curved instruments because they are effective in preventing the interference of instruments. Thus, we developed a novel curved cotton instrument, known as the "CS Two-Way HandleTM", for uniportal video-assisted thoracoscopic surgery. The CS Two-Way HandleTM can be used not only as a cotton bar but also as a suction aid. Moreover, surgical smoke can be suctioned with the insertion of cotton. This instrument was introduced in our institution in September 2019, along with some other prototypes. When anatomical lung resection using uniportal video-assisted thoracoscopic surgery was first introduced, there were some instances of conversion to conventional multiportal video-assisted thoracoscopic surgery. However, after the CS Two-Way HandleTM introduction, the procedure has become easy to perform and the need for conversion to conventional methods has reduced. The main uses of the CS Two-Way HandleTM are: (I) exposure of the surgical view, (II) lymph node dissection, (III) bleeding control, (IV) suction, and (V) evacuation of surgical smoke. We present our experiences using the CS Two-Way HandleTM in uniportal video-assisted thoracoscopic surgery.

Metachronous bilateral immunoglobulin G4-related pleuritis: A case report and literature review.

Immunoglobulin G4-related disease (IgG4-RD) is a newly recognized disease, and therefore its clinical features are not yet fully understood. Here, we describe a surgical case of metachronous bilateral IgG4-related pleuritis and postoperative chylothorax. This case could provide key insights into the pathology of IgG4-RD from a surgical perspective. We present a 70-year-old woman who had a right pleural mass. Video-assisted thoracoscopic pleural mass resection was performed, and the patient was diagnosed with right-sided IgG4-related pleuritis. Two years later, she was also diagnosed with left-sided IgG4-related pleuritis. We suspected the presence of IgG4-positive plasma cell infiltration. Additionally, she experienced a complicated postoperative chylothorax on the left side. It is important to consider the altered course of lymphatic vessels when extensively removing the pleura near the right thoracic duct. The occurrence of metachronous bilateral IgG4-associated pleuritis has not been previously reported, making this case particularly significant for understanding the pathology of IgG4-RD from a surgical standpoint.

Multicellular structures in thin free liquid films induced by thermocapillary effect.

HYPOTHESIS: Multicellular convective structures that are induced in a fluid exposed to temperature difference are commonly observed in nature and in daily life. Different types of basic flow patterns are induced in a free liquid film by thermocapillary effect, whereas the formation of such multicellular structures has not been hitherto unravelled. EXPERIMENTS: A thin film of high-Prandtl-number liquid is prepared in a rectangular aperture of the order of 0.1 mm in thickness sustained by its surface tension. A designated temperature difference is imposed between the end surfaces of the aperture to generate a thermocapillary-driven convection in the free liquid film. We monitor the induced thermal flow patterns to evaluate the cell numbers and their wavelength by experimental and numerical approaches. FINDINGS: The multicellular structure is established by the thermocapillary effect in the free liquid films. The cell number increases in a stepwise manner as the liquid-film width increases. When the cell number increases, another pair of the cells always newly emerges. We determine the wavelength in a non-dimensional manner, and present the variation of the wavelength against the aspect ratio corresponding to the liquid-film width. The results are compared to those of convectional Marangoni-Bénard convection.

Advances and safe use of energy devices in lung cancer surgery.

OBJECTIVES: A clear understanding of energy devices would help achieve high effectiveness and safety and guide the selection of devices. The present review aimed to elucidate the efficacy and adverse events of energy devices in lung cancer to guide the selection of appropriate devices depending on the situation. METHODS: Four major databases were searched electronically for relevant articles published until 16 April 2021. The reference lists of the identified papers were examined. We excluded (1) irrelevant studies, (2) manuscripts published in languages other than English and Japanese, (3) duplicates, and (4) studies for which the full text was not available in the databases. The results and key information obtained were summarized by means of a narrative approach. RESULTS: A total of 78 papers were included in the review and these were categorized according to the main topic of investigation as follows: (1) electrosurgery-related injuries, (2) fundamentals of electrosurgery, (3) monopolar devices, (4) bipolar electrosurgical devices, (5) ultrasonic energy devices, (6) energy devices in lung cancer surgery, (7) operating room fire risks, and (8) basic principles of surgery. CONCLUSIONS: Understanding energy devices could help us use them in a more effective and safer manner. Knowledge of their selection criteria (suitability), merits, risks, and safety precautions relevant to each process of lung cancer surgery could guide appropriate selection.

Decreased postoperative complications, neuropathic pain and epidural anesthesia-free effect of uniportal video-assisted thoracoscopic anatomical lung resection: a single-center initial experience of 100 cases.

Background: We aimed to analyze perioperative complications, postoperative neuropathic pain, and the necessity of epidural anesthesia in uniportal video-assisted thoracoscopic surgery (U-VATS) compared to conventional multiportal VATS (M-VATS) for anatomical lung resection. Methods: This retrospective study included all patients who underwent elective VATS lobectomy and segmentectomy between April 2016 and December 2019. The exclusion criteria were as follows: age ≤19 years, planned thoracotomy, re-operation in thoracic surgery, median sternotomy, robot-assisted thoracic surgery, simultaneous resection of extrathoracic organs, locally invasive lung tumor with bronchoplasty or angioplasty, past or current neuropathic pain, and a large tumor with a minimum diameter ≥5 cm. M-VATS had 4 ports approach. U-VATS port positions were placed by extending the thoracoscope port of M-VATS. Results: U-VATS patients showed significant differences compared to M-VATS patients: smaller intraoperative bleeding (1 vs. 30 mL; P=0.0010), shorter operative time (141 vs. 183 min; P<0.0001), post-hospitalization (5 vs. 8 days; P=0.0002), fewer complications (23.9% vs. 40.9%; P=0.048), less acute pain, less postoperative neuropathic pain (32.4% vs. 52.1%; P=0.027) and shorter duration of neuropathic pain (30 vs. 60 days; P=0.041). For the postoperative neuropathic pain and pain score until postoperative day 5, there were no differences between the groups with and without epidural anesthesia. Conclusions: As a single-center initial experience, U-VATS lobectomy and segmentectomy seemed safe and minimally invasive based on not only postoperative neuropathic pain and complications but also time management. U-VATS would provide better pain control, without epidural anesthesia.

Effectiveness and failure factors of manual aspiration using a small needle for large pneumothorax in stable patients.

Background: Manual aspiration as the initial management of a large pneumothorax in a clinically stable patient has been reported to be safe and effective. However, the effect with smaller needles, the number of aspiration, the indication other than spontaneous pneumothorax and failure factors are unknown. We assessed the effectiveness and failure risk factors of manual aspiration up to three using a 20- or 22-gauge (G) needle in patients with a large, clinically stable pneumothorax. Methods: We included 107 clinically stable patients with large pneumothorax. Patients who were unstable, required a ventilator, underwent chest tube drainage or had an observed small pneumothorax, bilateral pneumothorax, hemopneumothorax, or postoperative pneumothorax were excluded. Up to three aspirations were performed using 20- or 22-G intravenous needles. When the aspiration volume was ≥2,500 mL or lung expansion did not occur, a chest tube was placed. Results: The first aspiration was successful in 57 patients (53.3%), the second in 16 patients (59.3%), and the third in eight patients (80.0%). No patient experienced any obvious complications or required emergent hospitalization or surgery after aspiration. Aspiration failure was correlated with an inter-pleural distance >20 mm at the level of the hilum [odds ratio (OR): 4.93; 95% confidence interval (CI): 1.49-22.71; P=0.0075], spontaneous secondary pneumothorax (OR: 3.11; 95% CI: 1.14-8.76; P=0.027), and ≤24 h from onset to presentation (OR: 2.95; 95% CI: 1.12-8.26; P=0.028). There were no significant differences in intrathoracic pressure after aspiration or plasma factor XIII levels between patients with resolved and persistent pneumothorax. Conclusions: Manual aspiration up to three times using a small needle might be one of a treatment option in clinically stable patients with any large pneumothorax. Aspiration failure was correlated with an inter-pleural distance >20 mm at the level of the hilum, spontaneous secondary pneumothorax, and ≤24 h from onset to presentation.

Intraoperative methods for wrapping anastomoses after airway reconstruction: a case series.

Background: Anastomosis management is the main challenge of airway resection and reconstruction, and postoperative anastomotic complications, including ischemia, stenosis, dehiscence, and separation may lead to severe outcomes and a poor prognosis. The anastomotic buttress is vital in airway reconstruction, but the selection of surgical buttress and reinforcement remains controversial. We aimed to demonstrate and evaluate the buttress options of anastomosis, including their preoperative characteristics, the intraoperative process, and the incidence of postoperative complications to help address the controversy regarding anastomosis management. Methods: This retrospective study was conducted at a single institution. Patients who underwent airway reconstruction with anastomotic wrapping from Jan. 2019 to Sep. 2021 were enrolled in this study and preoperative characteristics and operational features were collected. All patients were carefully followed up by telephone and outpatient. Their postoperative complications and postoperative status after 6 months were recorded. The surgical procedures and clinical characteristics of the buttress options of anastomosis were assessed. Results: A total of 62 patients undergoing either cervical tracheal, thoracic tracheal, carinal, or secondary carinal and main bronchus resection and reconstruction were evaluated. The anastomotic buttress used included mediastinal pleural flap (24/62, 38.7%), anterior cervical muscle (14/62, 22.6%), sternocleidomastoid (2/62, 3.2%), thymus flap (12/62, 19.4%), intercostal muscle flap (2/62, 3.2%), biological patch (2/62, 3.2%), prepericardial fat (1/62, 1.6%), thyroid gland (1/62, 1.6%), pectoralis major flap (2/62, 3.2%), and omental flap (2/62, 3.2%). All procedures produced satisfactory results without short-term anastomotic complications. A follow-up for 6 months was conducted and all patients were alive postoperatively. Tracheomalacia stenosis postoperatively occurred in 3 patients and they were subsequently treated with an endotracheal stent. One patient had tumor recurrence 3 months after surgery and received adjuvant chemotherapy. Conclusions: Various anastomotic wrapping materials are used in airway reconstruction. Different utilizations of buttress are selected according to the anatomic characteristics and the reconstruction method used. This study indicated that appropriate surgical buttresses for wrapping anastomoses are legitimate alternatives to reduce the risk of anastomotic complications.

[Lung biopsy by video-assisted thoracic surgery in patient with untreated Evans syndrome].

A 78-year-old man referred to our hospital with the chief complaints of anorexia, general malaise, rash, and weight loss. Laboratory examination revealed pancytopenia, hyperglobulinemia, generalized adenopathy, and multiple pulmonary nodules. Video-assisted thoracic surgery (VATS) was performed to diagnose pulmonary nodules. After operation, it was difficult to achieve hemostasis for a while. Finally, the patient was diagnosed as pulmonary cryptococcosis and Evans syndrome.

A simplified model for determining the cutting plane during thoracoscopic anatomical partial lobectomy of the right lower lobe.

BACKGROUND: Few studies have examined the use of two-dimensional computed tomography (2D CT) and three-dimensional (3D) reconstruction images to determine the intersegmental plane (ISP) for pulmonary segmentectomy, but a systematic approach and nomenclature are currently lacking. This current study used 3D reconstruction of CT imaging to analyze variations in the right lower lobe's pulmonary ISP and created a simplified model to determine the optimum cutting plane (CP) for clinical application for operative planning and use during thoracoscopic anatomical partial lobectomy (APL). METHODS: Between January 2018 and October 2019, 325 patients with pulmonary lesions were identified who underwent thin-slice CT scans of the chest. The ISPs were identified by analyzing the 2D CT scans and 3D reconstruction images and the anatomical characteristics segmental boundary. The CP for the thoracoscopic procedure was then determined within the safe surgical margins, and a simplified CP model was created. RESULTS: The boundary between adjacent lung segment A and segment B was be expressed as "ISP: Sa-Sb". The ISP was divided into venous ISP (VISP), arterial ISP (AISP), and bronchial ISP (BISP). The proposed model of the CP can be expressed as follows: CP (f) = (V/A/B) ISP (x) + (V/A/B) sub ISP (y) + (V/A/B) sub-sub ISP (z). CONCLUSIONS: This report is a first attempt to provide a nomenclature for identifying the ISP, and create a simplified model for determining the CP for thoracoscopic partial lobectomy.

Adverse factors and postoperative neuropathic pain in challenging video-assisted thoracoscopic surgery.

BACKGROUND: Whether challenging video-assisted thoracoscopic surgery (VATS) is a minimal invasive surgery remains controversial. This study aimed to analyze causes of challenging conventional multiple-port VATS (CVATS) and conversion to thoracotomy and postoperative pain to provide indications for VATS. METHODS: This was a two-center retrospective study. Challenging VATS was defined as CVATS with operation time ≥5 hours and it was converted to thoracotomy. This study included patients who were admitted to Joetsu General Hospital (Joetsu, Niigata, Japan) and Toyama University Hospital (Toyama, Japan) for elective CVATS between April 2013 and March 2019. The exclusion criteria were as follows: a planned thoracotomy, uniportal VATS, robot-assisted thoracoscopic surgery, and simultaneous resection of extrathoracic organs. RESULTS: A total of 911 (91.6%) patients underwent CVATS. Of these cases, 876 (96.2%) were suitable VATS cases. On the contrary, 35 cases (3.8%) were recognized as challenging VATS. In 21 (2.3%) cases, VATS took ≥5 hours, and 14 (1.5%) VATS cases were converted to thoracotomy. The causes were severe adhesions (62.9%), air leak (45.7%), body position changes (22.9%), large tumor (14.3%), bronchoplasty or angioplasty (8.6%), and bleeding (2.9%). The minimum diameter of large tumors was 61.4 mm (53-67 mm). In 15 (71.4%) patients, VATS took ≥5 hours, and 10 (71.4%) patients who were converted to thoracotomy developed postoperative neuropathic pain. CONCLUSIONS: In this study, VATS ≥5 hours and conversion from VATS to thoracotomy were complicated by postoperative neuropathic pain. In case of bronchoplasty, angioplasty, and large tumor with minimum diameter ≥5 cm, a thoracotomy approach would be appropriate depending on the skill and experience of the surgeon. In cases of local or vascular sheath adhesion, if operation progress is delayed, it may be necessary to set a time limit and decide to convert to thoracotomy, considering patient's safety first.