Balance of the prooxidant and antioxidant system is associated with mortality in critically ill patients.

It is well known that oxidative stress causes certain diseases and organ damage. However, roles of oxidative stress in the acute phase of critical patients remain to be elucidated. This study aimed to investigate the balance of oxidative and antioxidative system and to clarify the association between oxidative stress and mortality in critically ill patients. This cohort study enrolled 247 patients transported to our emergency department by ambulance. Blood was drawn on hospital arrival, and serum derivatives of reactive oxidant metabolites (dROMs, oxidative index) and biological antioxidant potential (BAP, antioxidative index) were measured. Modified ratio (MR) is also calculated as BAP/dROMs/7.51. There were 197 survivors and 50 non-survivors. In the non-survivors, dROMs were significantly lower (274 vs 311, p<0.01), BAP was significantly higher (2,853 vs 2,138, p<0.01), and MR was significantly higher (1.51 vs 0.92, p<0.01) compared to those in the survivors. The AUC of MR was similar to that for the APACHE II score. Contrary to our expectations, higher BAP and lower dROMs were observed on admission in non-survivors. This may suggest that the antioxidative system is more dominant in the acute phase of severe insults and that the balance toward a higher antioxidative system is associated with mortality.

Outcomes of lung transplantation for idiopathic pleuroparenchymal fibroelastosis.

PURPOSE: This study was performed to compare the outcome of lung transplantation (LT) for idiopathic pleuroparenchymal fibroelastosis (IPPFE) with that of LT for idiopathic pulmonary fibrosis (IPF). METHODS: We reviewed, retrospectively, all adult patients who underwent LT for IPPFE or IPF in Japan between 1998 and 2018. RESULTS: There were 100 patients eligible for this study (31 with IPPFE and 69 with IPF). Patients with IPPFE tended to have a significantly lower body mass index (BMI) than those with IPF (median, 16.7 vs. 22.6 kg/m2, respectively; P < 0.01). However, Kaplan-Meier survival curves showed no significant difference in overall survival between the groups. The BMI did not increase in patients with IPPFE, even 1 year after LT (pretransplant, 16.5 ± 3.2 kg/m2 vs. 1 year post-transplant, 15.6 ± 2.5 kg/m2; P = 0.08). The percent predicted forced vital capacity (%FVC) 1 year after LT was significantly lower in the IPPFE group than in the IPF group (48.4% ± 19.5% vs. 68.6% ± 15.5%, respectively; P < 0.01). CONCLUSIONS: Despite extrapulmonary problems such as a flat chest, low BMI, and associated restrictive impairment persisting in patients with IPPFE, patient survival after LT for IPPFE or IPF was equivalent.

Double stenting with silicone and metallic stents for malignant airway stenosis.

For severe malignant airway stenosis, there are several types of commercially available airway stents, and each has its own advantages and disadvantages. We herein describe the safety and efficacy of combination stenting with silicone and metallic stents for patients with extended malignant airway stenosis. Seven patients with malignant airway stenosis were treated via combination stenting with a silicone stent and a metallic stent for extended airway stenosis from the central to peripheral airways. Five patients were diagnosed with advanced esophageal cancer, two of whom had tracheoesophageal fistulas. One patient had adenoid cystic carcinoma, and another had mediastinal tumor. There were no specific complications related to the double stenting. Combination stenting with silicone and metallic stents proved to be a safe option for patients with severe, extended, and complicated malignant airway stenosis.

Surgery or stereotactic body radiotherapy for elderly stage I lung cancer? A propensity score matching analysis.

PURPOSE: The aim of this study was to compare the outcomes of surgery and stereotactic body radiotherapy (SBRT) for elderly clinical stage I non-small cell lung cancer (NSCLC) patients. METHODS: Patients ≥80 years of age with clinical stage I NSCLC between August 2008 and December 2014 were treated either surgery or SBRT. Propensity score matching was performed to reduce bias in various clinicopathological factors. RESULTS: Surgery was performed in 57 cases and SBRT in 41 cases. In the surgery group, the operations included 34 lobectomies and 23 sublobar resections. In the SBRT group, 27 cases were given 48 Gy in 4 fractions, and 14 were given 60 Gy in 10 fractions. Similar characteristics were identified in age (82 years), gender (male:female ratio 2:1), tumor size (2.2 cm), carcinoembryonic antigen (3.6 ng/ml), Charlson comorbidity index (1), Glasgow prognostic scale (0), and forced expiratory volume in 1 s (1.7 L) after matching. Before matching, the 5-year overall survival (OS) in surgery (68.3%) was significantly better than that in SBRT (47.4%, p = 0.02), and the 5-year disease-specific survival (DSS) (94.1%, 78.2%, p = 0.17) was not significantly different between the groups. The difference in the 5-year OS became non-significant between the matched pairs (57.0%, 49.1%, p = 0.56). CONCLUSIONS: The outcomes of surgery and SBRT for elderly patients with the early stage NSCLC were roughly the same.

The surgical outcomes of lung cancer combined with interstitial pneumonia: a single-institution report.

PURPOSE: Several studies have reported that an acute exacerbation (AE) of idiopathic interstitial pneumonia (IIP) can occur after lung resection in patients with non-small cell lung cancer (NSCLC); however, the perioperative management strategy is controversial. METHODS: The data of lung cancer patients at Nagasaki University Hospital from June 1994 to October 2013 were retrospectively reviewed. RESULTS: Among all 1701 NSCLC patients who underwent lung resection, 59 (3.5%) had IIP. Five patients (8.5%) had an AE of IIP following lung resection, three (60%) of whom died in hospital. Univariate and multivariate analyses were performed to identify possible risk factors for AE. The univariate analyses identified LDH and the volume of blood loss as risk factors. The multivariate analysis identified no factors. The treatment for an AE included steroid pulse therapy and neutrophil elastase inhibitor therapy. Direct hemoperfusion with polymyxin B immobilized the fiber column and immunosuppressant therapy was attempted in some of the patients who did not respond to these treatments. CONCLUSION: Patients with lung cancer and IIP have a higher risk of chest surgery and a poor prognosis. Very careful surgery and perioperative management are needed, because AEs are often difficult to AE predict.

Ratio of C-reactive protein to albumin is a prognostic factor for operable non-small-cell lung cancer in elderly patients.

PURPOSE: The aim of this retrospective study was to evaluate inflammation-based scoring as a prognostic factor for operable non-small-cell lung cancer (NSCLC) in elderly patients. METHODS: We collected preoperative data from 108 patients aged above 80 years with NSCLC. Inflammation-based scoring systems, including the C-reactive protein to albumin ratio (CAR) and the Glasgow prognostic score (GPS), as well as other clinicopathological factors, were evaluated as potential prognostic factors. RESULTS: The median patient age was 82 (range 80-93) years and the 5-year overall and disease-specific survival rates were 49.7 and 73.9%, respectively. The cut-off value for CAR was calculated using a receiver operator characteristics analysis and patients were dichotomized accordingly. Patients with a low CAR had significantly higher overall survival than those with a high CAR (<0.028; 65.2% vs. ≥0.028; 31.0%, respectively; p < 0.01). In univariate analysis, female gender, a low Charlson comorbidity index of 0 or 1 and a low CAR were significantly identified in overall survival. On multivariate analysis, a low CAR (p = 0.03, hazard ratio: 2.13, 95% confidence interval 1.074-4.295) was identified as a significant prognostic factor. CONCLUSIONS: The preoperative CAR is a useful predictor of overall survival and could be a simple prognostic tool to help identify resectable NSCLC in elderly patients.

[Granuloma by Foreign Body Reaction to the Stapler Used for Partial Resection of the Lung].

A 66-year-old woman underwent right lower lobectomy and partial resection of the middle lobe for Stage I A double lung cancer. Five years after the operation, a routine computed tomography (CT) scan showed a mass on the staple line at the middle lobe. The mass was enlarged on CT scan after 6 months. A definitive diagnosis could not be made by bronchoscopic examination and fluoro-2-deoxy-glucose(FDG)/positron emission tomography( PET)-CT showed FDG uptake in the mass( early phase:SUVmax=3.24, late phase:SUVmax=4.31). Local recurrence of lung cancer was not completely denied, and right middle lobectomy was performed. Histopathologically, the resected specimen revealed granuloma with foreign body reaction. We should keep in mind the possibility of granuloma as differential diagnosis of lung cancer when using stapler.

Down-Regulation of Nogo-B Expression as a Newly Identified Feature of Intrahepatic Cholangiocarcinoma.

Nogo-B, located in the endoplasmic reticulum, is an isoform belonging to the reticulon protein family, which is expressed specifically in cholangiocytes and non-parenchymal cells in the liver. Nogo-B expression is down-regulated with the progression of liver fibrosis, but its distinct function in liver malignancies has not been fully clarified. We have hypothesized that Nogo-B expression may be altered in intrahepatic cholangiocarcinoma (ICC), a relatively rare type of primary liver cancer with highly malignant behavior. The present study aimed to investigate the relationship between Nogo-B expression, assessed by immunohistochemical staining, and clinicopathological factors and prognosis in 34 ICC patients. Positive expression was observed in 19 (56%) of 34 ICC specimens: 6 patients (18%) with positivity levels of 1+ (positive cells in 10-50% of cancer cells) and 13 patients (38%) with 2+ (positive cells over 50%). Importantly, the remaining 15 patients (44%) were categorized as negative expression (Nogo-B-positive cells, less than 10%). Conversely, the mass-forming type of ICC tended to express Nogo-B with the degree of 2+ positivity, compared to the periductal infiltration type (p = 0.064), and the mass-forming type showed a better 5-year survival rate (66% vs. 5%) after hepatectomy (p < 0.05). However, the degree of positivity was not associated with tumor relapse rate, disease-free and overall survival, although each of the periductal infiltration type, intrahepatic metastasis, larger tumor size, and lower microvessel counts was associated with lower survival rates. We propose that Nogo-B expression is down-regulated in ICC, the implication of which, however, remains to be investigated.

Management of unexpected intraoperative bleeding during thoracoscopic pulmonary resection: a single institutional experience.

PURPOSE: Unexpected intraoperative bleeding during thoracoscopic surgery, necessitating emergency conversion to thoracotomy, is gradually being reported. We reviewed our experience of encountering unexpected bleeding during thoracoscopic surgery. METHODS: We defined "unexpected intraoperative bleeding" as the need for hemostatic procedures with angiorrhaphy, with or without a sealant. The location, cause, and management of injured vessels, and perioperative outcomes were investigated and compared with those for patients without injured vessels. RESULTS: Between 2007 and 2014, a total of 241 thoracoscopic anatomical pulmonary resections were performed at our hospital. Twenty (8.3 %) of these patients required hemostatic procedures with angiorrhaphy, with or without a sealant. The main injured vessels were the pulmonary artery (n = 13) and vein (n = 3) and the main causes of injury were related to technical issues with energy devices and staplers. There were no morbidities related to intraoperative bleeding. The operation time and blood loss were significantly greater in the patients with vessel injury than in those without vessel injury, but perioperative morbidities and the duration of chest tube insertion (4.5 vs. 3.5 days, average, p = 0.20) and postoperative hospital stay (12.7 vs. 11.0 days, average, p = 0.08) were not significantly different. CONCLUSIONS: The frequency of unexpected bleeding was relatively high in this series, but its management and outcomes were satisfactory in terms of safety.

[Anastomotic Airway Complications after Lung Transplantation].

Anastomotic airway complications still remain an important issue after lung transplantation. Most of the complications are stenosis and anastomotic leakage. Stent insertion is one option for the stenosis. We review the anastomotic airway complications and report our recent experience of stent insertion using 3-dimensional printed airway model.

Timing of Mesenchymal Stromal Cell Therapy Defines its Immunosuppressive Effects in a Rat Lung Transplantation Model.

Cell therapy using mesenchymal stromal cells (MSCs) is being studied for its immunosuppressive effects. In organ transplantation, the amount of MSCs that accumulate in transplanted organs and other organs may differ depending on administration timing, which may impact their immunosuppressive effects. In vitro, adipose-derived mesenchymal stem cells (ADMSCs) suppress lymphocyte activation under cell-to-cell contact conditions. However, in vivo, it is controversial whether ADMSCs are more effective in accumulating in transplanted organs or in secondary lymphoid organs. Herein, we aimed to investigate whether the timing of ADMSC administration affects its immunosuppression ability in a rat lung transplantation model. In the transplantation study, rats were intramuscularly administered half the usual dose of tacrolimus (0.5 mg/kg) every 24 h after lung transplantation. ADMSCs (1 × 106) were administered via the jugular vein before (PreTx) or after (PostTx) transplantation. Cell tracking using quantum dots was performed. ADMSCs accumulated predominantly in the lung and liver; fewer ADMSCs were distributed in the grafted lung in the PreTx group than in the PostTx group. The rejection rate was remarkably low in the ADMSC-administered groups, particularly in the PostTx group. Serum tumor necrosis factor-α (TNF-α), interferon-γ, and interleukin (IL)-6 levels showed a greater tendency to decrease in the PreTx group than in the PostTx group. The proportion of regulatory T cells in the grafted lung 10 days after transplantation was higher in the PostTx group than in the PreTx group. PostTx administration suppresses rejection better than PreTx administration, possibly due to regulatory T cell induction by ADMSCs accumulated in the transplanted lungs, suggesting a mechanism different from that in heart or kidney transplantation that PreTx administration is more effective than PostTx administration. These results could help establish cell therapy using MSCs in lung transplantation.

Donor and Recipient Adipose-Derived Mesenchymal Stem Cell Therapy for Rat Lung Transplantation.

BACKGROUND: Mesenchymal stem cells (MSCs) are beginning to be proven as immunosuppressant in the field of organ transplantation. However, the effects of MSC origin (donor or recipient) on immunosuppression are not clear. Hence, we investigated the effects of recipient and donor adipose-derived MSCs (ADMSCs) on immunosuppression in a rat lung transplantation model. METHODS: Subjects were divided into no treatment, tacrolimus administration, recipient ADMSC administration, donor ADMSC administration, and mixed donor and recipient ADMSC administration groups. ADMSC-administered groups were also treated with tacrolimus. Histologic study, immunofluorescence, immunohistochemistry, enzyme-linked immunosorbent assay, and polymerase chain reaction were used for various analyses. RESULTS: Fluorescently labeled ADMSCs were predominant in the grafted donor lung, but not in the recipient lung, on day 5. On day 7, the pathologic rejection grades of the grafted donor lung were significantly lower in the ADMSC-administered groups (P < .05) and did not differ among these groups. Although serum hepatocyte growth factor and vascular endothelial growth factor levels did not differ among the groups, interleukin 10 level was slightly higher in the ADMSC-administered groups. The numbers of infiltrating regulatory T cells in the grafted lung were significantly higher in the ADMSC-administered groups (P < .05) but did not differ with cell origin. Transcriptional analysis suggested interleukin 6 suppression to be the main overlapping immunosuppressive mechanism, regardless of origin. Therefore, a donor or recipient origin may not influence the immunosuppressive efficacy of ADMSCs in our rat lung transplantation model. CONCLUSIONS: Collectively, the results indicate that allogenic ADMSCs, regardless of their origin, may exert similar immunosuppressive effects in clinical organ transplantation.

Anticancer agent α-sulfoquinovosyl-acylpropanediol enhances the radiosensitivity of human malignant mesothelioma in nude mouse models.

Malignant pleural mesothelioma (MPM) is a highly malignant disease that develops after asbestos exposure. Although the number of MPM cases is predicted to increase, no effective standard therapies have been established. The novel radiosensitizer α-sulfoquinovosyl-acylpropanediol (SQAP) enhances the effects of γ-radiation in human lung and prostate cancer cell lines and in animal models. In this study, we explored the radiosensitizing effect of SQAP and its mechanisms in MPM. The human MPM cell lines MSTO-211H and MESO-4 were implanted subcutaneously into the backs and thoracic cavities of immunodeficient KSN/Slc mice, then 2 mg/kg SQAP was intravenously administered with or without irradiation with a total body dose of 8 Gy. In both the orthotopic and ectopic xenograft murine models, the combination of irradiation plus SQAP delayed the implanted human MSTO-211H tumor growth. The analysis of the changes in the relative tumor volume of the MSTO-211H indicated a statistically significant difference after 8 Gy total body combined with 2 mg/kg SQAP, compared to both the untreated control (P = 0.0127) and the radiation treatment alone (P = 0.0171). After the treatment in each case, immunostaining of the harvested tumors revealed decreased cell proliferation, increased apoptosis and normalization of tumor blood vessels in the SQAP- and irradiation-treated group. Furthermore, hypoxia-inducible factor (HIF) 1 mRNA and protein expression were decreased, indicating reoxygenation in this group. In conclusion, SQAP improved hypoxic conditions in tumor tissue and may elicit a radiosensitizing effect in malignant mesothelioma models.

Preoperative tracheal resection and reconstruction simulations with patient-specific three-dimensional models.

Three-dimensional (3D) printers are increasingly being used for a variety of applications. In the surgical field, patient-specific organ models are increasingly being used as preoperative simulators for complicated surgeries. In this study, we describe the use of patient-specific 3D models for tracheal resection. We performed preoperative simulations for two patients diagnosed with tracheal ganglioneuroma and adenoid cystic carcinoma; the mimic operations suggested the necessity of a short cuff intubation tube across the surgical field, indicating the recommended amount of dissection around the trachea and bilateral hilum prior to tracheal reconstruction. The postoperative courses were free from any anastomotic or pulmonary complications. We described the availability of preoperative simulations for complicated tracheal resection and reconstruction using patient-specific 3D printed models. Mimic operations using the 3D printed models allowed accurate preparation and confidence in selection of the optimal surgical strategy.

Lung Microvascular Niche, Repair, and Engineering.

Biomaterials have been used for a long time in the field of medicine. Since the success of "tissue engineering" pioneered by Langer and Vacanti in 1993, tissue engineering studies have advanced from simple tissue generation to whole organ generation with three-dimensional reconstruction. Decellularized scaffolds have been widely used in the field of reconstructive surgery because the tissues used to generate decellularized scaffolds can be easily harvested from animals or humans. When a patient's own cells can be seeded onto decellularized biomaterials, theoretically this will create immunocompatible organs generated from allo- or xeno-organs. The most important aspect of lung tissue engineering is that the delicate three-dimensional structure of the organ is maintained during the tissue engineering process. Therefore, organ decellularization has special advantages for lung tissue engineering where it is essential to maintain the extremely thin basement membrane in the alveoli. Since 2010, there have been many methodological developments in the decellularization and recellularization of lung scaffolds, which includes improvements in the decellularization protocols and the selection and preparation of seeding cells. However, early transplanted engineered lungs terminated in organ failure in a short period. Immature vasculature reconstruction is considered to be the main cause of engineered organ failure. Immature vasculature causes thrombus formation in the engineered lung. Successful reconstruction of a mature vasculature network would be a major breakthrough in achieving success in lung engineering. In order to regenerate the mature vasculature network, we need to remodel the vascular niche, especially the microvasculature, in the organ scaffold. This review highlights the reconstruction of the vascular niche in a decellularized lung scaffold. Because the vascular niche consists of endothelial cells (ECs), pericytes, extracellular matrix (ECM), and the epithelial-endothelial interface, all of which might affect the vascular tight junction (TJ), we discuss ECM composition and reconstruction, the contribution of ECs and perivascular cells, the air-blood barrier (ABB) function, and the effects of physiological factors during the lung microvasculature repair and engineering process. The goal of the present review is to confirm the possibility of success in lung microvascular engineering in whole organ engineering and explore the future direction of the current methodology.

Enhanced airway stenting using a preoperative, three-dimensionally printed airway model simulation.

Three-dimensionally printed organ models that facilitate preoperative simulations have the potential to improve outcomes of surgical procedures. Here, we report a case involving a 54-year-old man diagnosed with lung cancer of the right upper bronchus that was invading the right main bronchus. A right upper lobectomy with carinoplasty was performed. Although complete excision of the tumor was achieved, exertional dyspnea redeveloped 4 months post-surgery. Chest computed tomography revealed that airway stenosis caused by granulation had deformed the airway. Ablation of the granulation and airway stenting was required to improve the patient's symptoms. Prior to performing airway stenting, a three-dimensionally printed airway model was constructed, and the Y-shaped silicone stent used was modified in accordance with the model. After stenting, both the right and left bronchi were preserved, and the patient's symptoms improved. The three-dimensional printed airway model enhanced the accuracy and safety of the airway stenting procedure performed.

Surgery or stereotactic body radiotherapy for metachronous primary lung cancer? A propensity score matching analysis.

OBJECTIVE: We compared outcomes after surgery or stereotactic body radiotherapy (SBRT) among patients with metachronous primary lung cancer (MPLC). METHODS: Patients with MPLC were treated with either surgery (2008-2018) or SBRT (2010-2018). We used propensity score matching (PSM) to reduce bias from various clinicopathological factors. MPLC was defined by the Martini and Melamed criteria. RESULTS: Of 77 patients, 51 underwent surgery and 26 received SBRT. Most median clinicopathological characteristics did not significantly differ between the surgery and SBRT groups (male sex: 67% vs 65%; age: 73 vs 77 years; time after first surgery: 6.2 vs 4.7 years; lobectomy as first procedure: 82% vs 85%; second tumor size: 11 vs 12 mm; clinical stage I: 96% vs 100%; CEA: 2.9 vs 3.0 ng/ml). However, the surgery group had significantly more ipsilateral second tumors (n = 71, 58%, P = 0.003), better performance status (P = 0.03), and preserved lung function (P = 0.02). Surgery, thus, tended to be selected for patients with good physical function and for the MPLC in the contralateral side. Five-year overall survival did not significantly differ between the surgery and SBRT groups, either before PSM (86.5% vs 65.8%, P = 0.24, log-rank) or after PSM (100% vs 84.4%, P = 0.73). CONCLUSIONS: Surgery and SBRT for MPLC patients are safe and feasible treatments with similar outcomes. However, this finding should be verified by a random controlled trial with a larger study cohort.

A case of emergent operation for a life-threatening infectious mediastinal cyst.

PURPOSE: Congenital mediastinal cysts are an uncommon but important diagnostic group. Most of these cysts are benign and asymptomatic in adults. However, some of them are clinically problematic due to the compression of neighboring organs, infection, or perforation. CASE PRESENTATION: A 20-year-old man presented with severe dyspnea. Imaging revealed a mediastinal cyst in the subcarinal space compressing his right pulmonary artery and airway, which was later diagnosed as a bronchogenic cyst. Due to quick symptom exacerbation, emergent cyst wall fenestration was performed through video-assisted thoracic surgery with "stand-by" extracorporeal membrane oxygenation. Complete cyst resection was difficult owing to adhesion of the cyst to the surrounding organs. The symptoms immediately resolved after surgery and the postoperative course was uneventful. CONCLUSION: Mediastinal bronchogenic cysts with life-threatening complications are rarely reported in adults. However, this case was life-threatening due to airway and vascular compression; emergent surgical care should be considered in such cases.

Replacement of Rat Tracheas by Layered, Trachea-Like, Scaffold-Free Structures of Human Cells Using a Bio-3D Printing System.

Current scaffold-based tissue engineering approaches are subject to several limitations, such as design inflexibility, poor cytocompatibility, toxicity, and post-transplant degradation. Thus, scaffold-free tissue-engineered structures can be a promising solution to overcome the issues associated with classical scaffold-based materials in clinical transplantation. The present study seeks to optimize the culture conditions and cell combinations used to generate scaffold-free structures using a Bio-3D printing system. Human cartilage cells, human fibroblasts, human umbilical vein endothelial cells, and human mesenchymal stem cells from bone marrow are aggregated into spheroids and placed into a Bio-3D printing system with dedicated needles positioned according to 3D configuration data, to develop scaffold-free trachea-like tubes. Culturing the Bio-3D-printed structures with proper flow of specific medium in a bioreactor facilitates the rearrangement and self-organization of cells, improving physical strength and tissue function. The Bio-3D-printed tissue forms small-diameter trachea-like tubes that are implanted into rats with the support of catheters. It is confirmed that the tubes are viable in vivo and that the tracheal epithelium and capillaries proliferate. This tissue-engineered, scaffold-free, tubular structure can represent a significant step toward clinical application of bioengineered organs.

Successful resection to treat idiopathic azygos vein aneurysm.

Azygos vein aneurysm is a rare disease. Surgical resection is usually performed when it ruptures. To avoid the thromboembolism, procedures that do not touch or push the aneurysm are recommended. Herein, we report a case of idiopathic azygos vein aneurysm. A 56-year-old woman was admitted to the hospital for right lateral chest pain. Chest enhanced multi-detector CT revealed an azygos vein aneurysm in the posterior mediastinal space. No thrombus in the aneurysm was detected before surgery. Video-assisted thoracic surgery was performed to treat the aneurysm. The patient was discharged from the hospital 4 days after surgery. Video-assisted thoracic surgery was a good option to treat an azygos vein aneurysm, and an enhanced multi-detector CT was useful for performing surgery safely.