Comparison of imaging changes in pulmonary artery diameter at the occlusion site using silk or metal clamps for pulmonary artery troubles.

OBJECTIVES: We analysed our clinical experience using silk sutures [the double-loop technique (DLT)] or DeBakey type vascular clamp (DeBakey clamp) for pulmonary artery (PA) troubles during anatomical lung resection to validate its practicality and safety. METHODS: We retrospectively reviewed the records of patients who underwent either of the above clamping techniques during anatomical lung resection at our hospital between April 2007 and August 2022. We measured the PA diameter at the occlusion site on computed tomography images acquired within 1 year pre- and postoperatively. The difference between pre- and postoperative diameters of the occlusion sites was calculated as the change in the PA diameter. We zoned the occlusion site of the PA to adjust for variation. PA deformation was evaluated as an adverse event caused by clamping. RESULTS: Ultimately, 27 and 26 patients who underwent the DLT and DeBakey clamp, respectively, were included. No additional injury due to the clamp procedure was found in either group. For zone R1/L1, defined as the main PA, the median changes in the PA diameter were 0.02 (-0.7 to 0.27) mm for the DLT and 0.36 (-0.28 to 0.89) mm for the DeBakey clamp. No significant differences were observed between the 2 groups (P = 0.106). Furthermore, no aneurysms, dissections, or stenoses were found in either group. CONCLUSIONS: The DLT and DeBakey clamp had only minimal effects on the occlusion site of the PA. The DLT is a practical thoracoscopic technique for PA bleeding when primary haemostasis has been achieved.

[Crucial Techniques for Chest Tube Placement and Postoperative Management].

Postoperative management of thoracic surgery with an indwelling chest tube is common, and knowledge about it is essential. A postoperative chest tube has four roles:1) to reinflate the lung, 2) to observe the condition of the thoracic cavity and acquire information regarding the outcomes, 3) to prevent complications, and 4) to treat pulmonary air leaks and empyema (chemical pleurodesis et ct). Although postoperative complications have decreased in recent years following advances in video-assisted thoracoscopic surgery( VATS) and devices such as stapling devices and vascular sealing systems (VSS), postoperative chest tube placement is still common. Therefore, a thorough knowledge of chest tube management is extremely important in thoracic surgery. Here, we have described, in detail, the management of a postoperative chest tube at our hospital.

[Minimally Invasive Robot-assisted Thoracoscopic Surgery for Mediastinal Tumor].

Robot-assisted thoracoscopic surgery( RATS) and video-assisted thoracoscopic surgery are minimally invasive surgical approaches to the chest wall that avoid sternotomy. We report on the innovations in RATS mediastinal tumor surgery performed in our department. We use a lateral approach, and the robotic arm is inserted between the third, fifth, and seventh intercostals and below the costal ribs. Carbon dioxide gas is insufflated using a pneumoclear insufflator. A small thoracotomy is made in the fifth intercostal space and an Alnote Lapsingle is placed and a scope and assistant port are implanted. The Alnote Lapsingle is used to keep the chest wall airtight and stable. The scope is moved less, reducing interference with the assistant. Tissue can now be placed in the retrieval bag with a good surgical field of view. After much trial and error, RATS mediastinal tumor surgery can now be performed more easily.

Experimental and histological evaluation of different clamp technique for pulmonary artery.

OBJECTIVES: The double-loop technique has been used in our clinical settings for pulmonary arterioplasty and/or injured artery repair during thoracoscopic anatomical lung resection. We evaluated the pressure resistance capacity and intimal load to determine the effectiveness and safety of the double-loop technique. METHODS: The double-loop technique, DeBakey clamp, Fogarty clamp, endovascular clips and vessel loop technique were evaluated. During an experimental study, a polyvinyl alcohol main pulmonary artery model, manometer and in-deflation device were used to measure the burst pressure. The maximum clamp pressure was measured using a pressure-measuring film. Each measurement was performed 10 times. During the histological study, we measured the burst pressure and evaluated the intimal damage of the human pulmonary artery associated with the double-loop technique and DeBakey clamp. RESULTS: The experimental burst pressure (mmHg) and maximum clamp pressure (MPa) between the double-loop technique and DeBakey at the third notch were not significantly different (24.6 ± 2.8 and 21.8 ± 2.8, P = 0.094; 1.54 ± 0.12 and 1.49 ± 0.12, P = 0.954). During the histological study, the burst pressures of the double-loop technique and DeBakey at the third notch were also not significantly different (P = 0.754). Furthermore, the double-loop technique resulted in only intimal deformation in each five samples. CONCLUSIONS: The double-loop technique is feasible for thoracoscopic anatomical lung resection because it has similar pressure resistance capacity and intimal load as DeBakey at the 3rd notch.

[Mullerian Cyst in the Posterior Mediastinum Resected by Robot-assisted Thoracic Surgery:Report of a Case].

Mullerian cyst in the posterior mediastinum is a rare disorder. We report on the case of a woman in her 40s with a cystic nodule which is located in the right posterior mediastinum next to the vertebra at the level of tracheal bifurcation. The tumor was suggested to be cystic by preoperative magnetic resonance imaging (MRI). The tumor was resected with robot-assisted thoracic surgery. Pathology by hematoxylin-and-eosin (H&E) revealed a thin-walled cyst lined by ciliated epithelium without cellular atypia. The diagnosis of Mullerian cyst was confirmed by immunohistochemical staining which showed the positive findings for estrogen receptor (ER) and progesterone receptor of the lining cells.

[Novel Surgical Techniques for Lung Segmentectomy of Malignant Lung Tumors].

For a long time, lobectomy and lymph node dissection have been the standard surgery for treating non-small cell lung cancer. Recently, segmentectomy has been introduced as an alternative surgical procedure for treating early-stage lung cancer. Moreover, a growing number of segmentectomies are performed due to the increasing number of elderly patients, and the expansion of indications, including early- stage lung cancer with a ground glass nodule or peripheral nodule under 2 cm in diameter. However, the use of segmentectomy remains under debate. We have been performing thoracoscopic lung segmentectomy for malignant lung tumors since 2003. The number of surgeries has increased over the past few years, since robot-assisted lung resection of the right lobe became covered by health insurance in April 2018. In addition, lung segmentectomy is performed for lung metastases of malignant tumors in other organs. In deciding on the surgical approach, the increased technical difficulty of segmentectomy compared to lobectomy, owing to the anatomical complexity of the peripheral vessels and bronchi, needs to be considered, and novel surgical procedures and preoperative planning based on three-dimensional computed tomography( CT) images are necessary. We describe the preoperative management and surgical techniques used in approximately 250 lung segmentectomy procedures performed at our hospital up to May 2022, with no conversion to thoracotomy.

Number of lymph nodes dissected and upstaging rate of the N factor in robot-assisted thoracic surgery versus video-assisted thoracic surgery for patients with cN0 primary lung cancer.

PURPOSE: The accuracy of lymph node (LN) dissection in robotic surgery for lung cancer remains controversial. We compared the accuracy of LN dissection in robot-assisted thoracic surgery (RATS) vs. video-assisted thoracic surgery (VATS). METHODS: The subjects of this retrospective analysis were 226 patients with cN0 primary lung cancer who underwent robot-assisted or video-assisted thoracic lobectomy with LN dissection, in our department, between April, 2016 and February, 2021. We compared the numbers of all LNs and mediastinal LNs dissected, the time required for LN dissection, complications, and upstaging rates of the N factor between the groups. Furthermore, we performed an inverse probability of treatment weighting-adjusted analysis to reduce potential bias between the groups. RESULTS: The number of dissected LNs was higher in the RATS group in both the unweighted and weighted analyses. The time required for lymph node dissection was also longer in RATS. There was no significant difference in complications or in the upstaging rate of the N factor between the groups. CONCLUSION: More LNs were dissected with RATS. Thus, the usefulness of robot-assisted surgery for LN dissection needs to be investigated further.

[Thoracoscopic Superior and Subsuperior Segmentectomy of the Right Lower Lung for Lung Cancer].

The subsuperior segment (S*) is not frequently observed between the superior (S6) and posterior basal segments (S10). We present a case of video-assisted thoracoscopic surgery of S6+S* segmentectomy for a primary lung cancer patient. A 71-year-old man with a 20-mm nodule on the right S6, suspected of primary lung cancer( cT1bN0M0, stageⅠA2), was admitted to our hospital. Three-dimensional chest computed tomography (CT) revealed a subsuperior segmental bronchus (B*), originating from the common trunk of the lateral basal segmental bronchus( B9) and posterior basal segmental bronchus (B10). In order to obtain enough surgical margin, we performed S6+S* segmentectomy. The pathological diagnosis was invasive adenocarcinoma( pT1cN0M0, stageⅠA3). S* segmentectomy was considered to be useful method to ensure sufficient surgical margin when the lesion is in S* or in segments adjacent to it.

Tips for using forceps during uniportal video-assisted thoracoscopic surgery.

Uniportal video-assisted thoracoscopic surgery is usually performed using an ultrasonic coagulation cutting device in the dominant hand and a long suction device in the non-dominant hand. However, countertraction with forceps is often needed for dissection of a vessel sheath. Moreover, in uniportal video-assisted thoracoscopic surgery, which requires the simultaneous use of multiple instruments, the instruments tend to interfere with each other during the procedure because of the need to share a single incisional port. In this video tutorial, we present tips for using thoracoscopic forceps with bent tips and a 30° video thoracoscope in uniportal video-assisted thoracoscopic surgery.

Clinical effect of soft coagulation for air leak treatment during pulmonary lobectomy.

BACKGROUND: Soft coagulation using the VIO soft coagulation system is used to treat minor lung air leaks during pulmonary resection in Japan. We previously reported that it has a similar effect as the air leak treatment with fibrin glue. We evaluated the efficacy of soft coagulation using the VIO soft coagulation system for lung air leakage during pulmonary resection. METHODS: Intraoperative air leaks from the interlobar lung parenchyma were observed in 42 of the 283 patients who underwent video-assisted thoracoscopic surgery lobectomy between 2016 and 2018. We retrospectively reviewed these 42 patients who were treated using the VIO soft coagulation system for air leaks. We classified the air leaks in to grades using the Macchiarini scale score and evaluated the surgical outcomes of air leak treatment. RESULTS: Air leaks from the interlobar lung parenchyma having Macchiarini scale scores 1, 2, and 3 occurred in 8, 17, and 17 patients, respectively. In all the 8 patients with score 1 air leaks (100%), the air leaks could be controlled using the VIO soft coagulation system alone, and none had delayed pneumothorax requiring intervention. Of the score 2 and 3 air leaks, 52.9% and 35.3% were controlled using the VIO soft coagulation system alone, respectively. CONCLUSIONS: Macchiarini scale score 1 air leaks from the interlobar lung parenchyma could be well controlled using the VIO soft coagulation system. Therefore, soft coagulation with this system may be an alternative method for treating minor air leaks during pulmonary resection surgery.

Robot-assisted vs. video-assisted thoracoscopic surgery in lung cancer.

Background: The major advantages of robot-assisted surgery are the fine field of view provided by the high-precision three-dimensional (3D) images and the good operability provided by the robotic arms that enables precise movements. A growing number of retrospective studies have compared robotic-assisted thoracoscopic surgery (RATS) with video-assisted thoracoscopic surgery (VATS), but the number of cases is limited and the results are contradictory. Methods: We studied the medical records of primary lung cancer patients who underwent lobectomy with lymph node dissection between 2017 and 2020. Four hundred and eleven patients fulfilled the inclusion criteria in this study (RATS: 103; VATS: 308). We compared the perioperative factors and postoperative results of the VATS and RATS groups. Further, we adjusted background factors using propensity score matching (PSM) then compared the results of 200 patients (100 patients in each group). In this study, we matched interlobar fissure completeness, which affects operative difficulty and operative time; however, this has been superficially compared in previous studies. Results: After PSM, a significant difference was observed in the intraoperative blood loss (RATS: 53.3 mL, VATS: 120.3 mL, P=0.04). The rates of surgical complications were comparable between the groups (10.0% vs. 13.0%, P=0.66) with similar mean operation times (RATS: 215.0 min, VATS: 210.1 min, P=0.57). The mean postoperative stay in the RATS group was shorter than that in the VATS group (10.0 vs. 11.5 days, P=0.04). Conclusions: Initial experience of RATS had no obvious drawbacks when compared with that of VATS on propensity-matched analysis.

Simple smoke ventilation method for uniportal video-assisted thoracoscopic surgery.

Fogging of the thoracoscopic lens affects a surgeon's ability to maintain a clear operating field. In uniportal video-assisted thoracoscopic surgery, the thoracoscopic lens tends to fog when the surgeon does not hold a suction instrument. Thus, a suction instrument needs to be held by the surgeon's nondominant hand to remove surgical smoke, mist, and moisture. Here, we describe a simple, easy and cost-effective surgical smoke ventilation technique for uniportal video-assisted thoracoscopic surgery using a suction catheter to solve the problem. We present this technique and comment on its advantages, including decreased cost and improved surgical visualization.

Pulmonary vessels and bronchus anatomy of the left upper lobe.

PURPOSES: The bronchopulmonary vascular bifurcation patterns in the upper lobe of the left lung are diverse. Therefore, it is important for general thoracic surgeons to understand the detailed anatomy of the pulmonary segments when performing thoracoscopic anatomical pulmonary resection. This study aimed to analyze the bronchovascular patterns of the left upper lobe and summarize the anatomical information associated with pulmonary anatomical pulmonary resection. METHODS: We reviewed the anatomical patterns of pulmonary vessels and the left lung bronchus of 539 patients using computed tomography imaging data including those obtained using three-dimensional computed tomography. We herein report the anatomic structure in the left upper lobe. RESULTS: Regarding the superior division bronchi, a pattern of trifurcation into B1+2, B3, lingular division bronchus was observed in nine patients (1.7%). A pattern of proximal bifurcation of B4 was found in eight patients (1.5%). Regarding the lingular veins (LV), patterns of LV drainage into the left lower pulmonary vein were observed in 22 patients (4.1%). Regarding the pulmonary artery, mediastinal lingular arteries (MLA) were found in 161 patients (29.9%). CONCLUSION: The bifurcation patterns of the bronchovascular region in the upper lobe of the left lung were clarified. These results should be carefully noted when performing anatomical pulmonary resection.

Subcarinal Lymph Node Dissection in Solo Robot-assisted Thoracic Surgery.

The surgical instruments used in robot-assisted thoracic surgery are flexible to enable the surgeon to approach the surgical field from any direction. However even in robot-assisted thoracic surgery subcarinal lymph node dissection requires a precise technique suitable for a small area surrounded by important organs. We present a method of subcarinal node dissection with solo robot-assisted thoracic surgery using a bronchial traction method and a metal basket suction device, the Dobon (Senko Medical Instrument Mfg, Tokyo, Japan).

Anatomy of the left subsuperior segment for segmentectomy.

PURPOSE: The subsuperior segmental bronchi (B*) forms the subsuperior segment (S*) between the superior (S6) and basal segment (S7, S8, S9, S10) of the lung. However, the anatomical planes of S* remains undefined. The present study clarified the anatomical features of S*. METHODS: We reviewed the anatomical patterns of pulmonary vessels and the left lung bronchus in 539 patients using three-dimensional computed tomography. We report the anatomic structure in S*. RESULTS: A total of 537 patients were analyzed. B* was observed in 129 (24.0%) patients. The intersegmental vein between S6 and S* was complete in all cases. The absence of intersegmental veins of S* was observed in 77 (14.3%) patients, reaching 59.7% of B* cases. Twenty-two (4.1%) cases of B* diverged from the trunk of the basal bronchus, and about half of the B* branched to the dorsolateral (n = 77, 14.3%) or dorsal (n = 2, 0.37%) direction. CONCLUSION: Our study revealed the branching patterns of B* and anatomical intersegmental veins of S*. Our results provide useful information regarding anatomical segmentectomy including or adjusting to the left S*.

Simple lung retraction method for uniportal video-assisted thoracoscopic surgery.

In conventional multiportal video-assisted thoracoscopic surgery, devices such as cotton-tipped applicators are used instead of graspers to avoid injuring the fragile lung tissue while stabilizing the lung and securing the surgical visual field. However, in uniportal video-assisted thoracoscopic surgery, which requires the simultaneous use of multiple instruments, the instruments tend to interfere with each other during the procedure because they share a single incisional port. Here, we describe a simple, easy and cost-effective lung retraction technique using cotton swabs to solve the problem. We present this technique and comment on its advantages, including decreased cost and improved surgical visualization.

Risk factors for atelectasis of the middle lobe after right upper lobectomy: preoperative bronchial diameter and stapling of the fissure.

BACKGROUND: Atelectasis of the middle lobe after right upper lobectomy is often seen. However, the risk factors for atelectasis are uncertain. Therefore, we assessed cases in our institution and investigated risk factors for atelectasis of the middle lobe following right upper lobectomy. METHODS: We identified 354 cases in which right upper lobectomy had been performed in our institution between January 2009 and December 2018, and 342 were included in this retrospective analysis. We divided patients into two groups according to the presence of postoperative atelectasis of the middle lobe, and then preoperative clinical variables and perioperative variables were compared between the two groups. Multivariable analyses for postoperative atelectasis of the middle lobe were performed using the logistic regression model. RESULTS: Middle lobe atelectasis was detected in 59 cases (17.3%). Multivariable analysis demonstrated that the preoperative diameter of the middle lobe bronchus [P=0.012; confidence interval (CI), 0.525-0.930] and stapling of the fissure between the upper and middle lobes (P=0.004; CI, 1.997-37.050) were independent risk factors for postoperative atelectasis of the middle lobe. CONCLUSIONS: A small preoperative diameter of the middle lobe bronchus and stapling of the fissure between the upper and middle lobes are risk factors for middle lobe atelectasis following right upper lobectomy.

[Congenital Pericardial Defect Incidentally Found at Thoracoscopic Left Upper Lobe Resection:Report of a Case].

We report a rare case of a congenital pericardial defect that was incidentally found at thoracoscopic left upper lobe resection in a patient with lung cancer. A 75-year-old man with a left upper lobe lung cancer was referred to our hospital. We performed thoracoscopic left upper lobectomy and incidentally found a pericardial defect intraoperatively. Careful lymph node dissection was necessary to avoid injury of phrenic nerve and pulmonary artery. Surgery for lung cancer was completed without pericardial repair. After surgery, no complications associated with the pericardial defect has not been encountered.

[Thoracoscopic Pulmonary Resection in Lung Cancer Patients with Pleural Adhesion].

When a presence of significant pleural adhesion is identified at the beginning of surgery, multiple factors determine the outcome of the surgery, particularly when it is performed thoracoscopically. These factors include identification of adhesion at the beginning of the surgery, as well as procedures involved in dissection and additional incisions. If the adhesion is partial, the lack of observation during creation of the surgical field can lead to damage being caused outside the field of view due to traction. Thus, it is important to focus observations. At our department, we started performing thoracoscopic surgery in 1992. Currently, over 80% of annual surgical cases are performed thoracoscopically. We will review our thoracoscopic surgery cases that involved pleural adhesion and discuss the tools and techniques used, as well as providing additional tips for ensuring successful thoracoscopic surgery.