Impact of pulmonary vein-first ligation during lobectomy on the postoperative survival and recurrence rates in patients with non-small cell lung cancer: a multicenter propensity score-matched study.

PURPOSE: Surgical manipulation of the lungs increases the number of circulating tumor cells and the subsequent risk of metastasis in patients with lung cancer. This study investigated whether or not ligating the tumor-draining pulmonary vein first during lobectomy could improve the prognosis of these patients. METHODS: We retrospectively evaluated patients who underwent curative lobectomy for solitary nonsmall-cell lung carcinoma between January 2012 and December 2016. We divided the patients into the vein-first group, in which all associated pulmonary veins were dissected and severed before cutting the pulmonary artery, bronchus, or pulmonary fissure, and the other procedure group. RESULTS: Overall, we included 177 and 413 patients in the vein-first and other procedure groups, respectively. Propensity score matching yielded 67 pairs of patients. The 5-year overall survival (85.6% [95% confidence interval, 77.3-94.8%] vs. 69.4% [58.7-81.9%], P = 0.03%) and recurrence-free survival (73.4% [63.3-85.1%] vs. 53.5% [42.5-67.3%], P = 0.02) were significantly better in the vein-first group than in the other procedure group. The cumulative recurrence rate at 5 years post-surgery was significantly lower in the vein-first group than in the other procedure group (21.7% vs. 38.3%, P = 0.04). CONCLUSION: Our study suggests that ligating the pulmonary vein first during lobectomy for lung cancer can improve the overall survival, recurrence-free survival, and cumulative recurrence rate.

Dose Optimization of Intravenous Indocyanine Green for Malignant Lung Tumor Localization.

Background: Intravenously administered indocyanine green (ICG) accumulates in lung tumors, facilitating their detection via a fluorescence spectrum measurement. This method aids in identifying tumor locations that are invisible to the naked eye. We aim to determine the optimal ICG dose and administration method for accurate tumor identification during lung resection surgeries, utilizing a novel ICG fluorescence spectroscopy system for precise tumor localization. Materials and Methods: ICG should be dissolved in the provided solution or distilled water and administered intravenously approximately 24 h before surgery, beginning with an initial dose of 0.5 mg/kg. If the tumor detection rate is insufficient, the dose may be gradually increased to a maximum of 5.0 mg/kg to determine the optimal dosage for effective tumor detection. This fluorescence spectroscopy during surgery may reveal additional lesions that remain undetected in preoperative assessments. The primary endpoint includes the correct diagnostic rate of tumor localization. The secondary endpoints include the measurement of the intraoperative ICG fluorescence spectral intensity in lung tumors, the assessment of the operability and safety of intraperitoneal ICG administrations, the measurement of the ICG fluorescence spectral intensity in surgical specimens, the comparison of the spectral intensity in lung tissues during collapse and expansion, the correlation between ICG camera images and fluorescence spectral intensity, and the comparison of fluorescence analysis results with histopathological findings. The trial has been registered in the jRCT Clinical Trials Registry under the code jRCTs011230037. Results and Conclusions: This trial aims to establish an effective methodology for localizing and diagnosing malignant lung tumors, thereby potentially improving surgical outcomes and refining treatment protocols.

A simple and safe surgical technique for nonpalpable lung tumors: One-stop Solution for a nonpalpable lung tumor, Marking, Resection, and Confirmation of the surgical margin in a Hybrid operating room (OS-MRCH).

When performing thoracoscopic partial resections of nonpalpable lung tumors such as ground-glass opacities (GGOs) and small tumors, detecting the location of the lesion and assessing the resection margins can be challenging. We have developed a novel method to ease this difficulty, the One-stop Solution for a nonpalpable lung tumor, Marking, Resection, and Confirmation of the surgical margin in a Hybrid operating room (OS-MRCH), which uses a hybrid operating room wherein the operating table is seamlessly integrated with cone-beam computed tomography (CBCT). We performed the OS-MRCH method on 62 nodules including primary lung cancer presenting with GGO. Identification of the lesion and confirmation of the margin were performed in 58 of the cases, while nodules were detected in all. The frequency of computed tomography (CT) scans performed prior to resection was one time in 51 cases, two times in eight cases, and ≥3 times in three cases. Additional resection was performed in two cases. The median operative time was 85.0 minutes, and the median pathological margin was 11.0 mm. The key advantages of this method are that all surgical processes can be completed in a single session, specialized skill sets are not required, and it is feasible to perform in any facility equipped with a hybrid operating room. To overcome its disadvantages, such as longer operating time and limited patient positioning, we devised various methods for positioning patients and for CT imaging of the resected specimens. OS-MRCH is a simple, useful, and practical method for performing thoracoscopic partial resection of nonpalpable lung tumors.

Acute onset of constrictive pericarditis due to acute myelomonocytic leukemia: A case and literature review.

We herein present a fatal case of constrictive pericarditis (CP) due to acute myelomonocytic leukemia (AMML) in a patient who initially complained of an acute onset of chest pain two days after COVID-19 vaccination. An autopsy revealed pericardial infiltration of leukemic cells. CP is rarely associated with leukemia and only 14 cases have been reported in the literature. The etiology of CP in previous reports included leukemic infiltration, graft-versus-host disease, drug-induced, post-radiation, autoimmune, and otherwise unidentified. This case indicates that leukemic infiltration can cause CP and that clinicians should include leukemia in the differential diagnosis of CP.

Developing a Virtual Reality Simulation System for Preoperative Planning of Robotic-Assisted Thoracic Surgery.

Background. Robotic-assisted thoracic surgery (RATS) is now standard for lung cancer treatment, offering advantages over traditional methods. However, RATS's minimally invasive approach poses challenges like limited visibility and tactile feedback, affecting surgeons' navigation through com-plex anatomy. To enhance preoperative familiarization with patient-specific anatomy, we devel-oped a virtual reality (VR) surgical navigation system. Using head-mounted displays (HMDs), this system provides a comprehensive, interactive view of the patient's anatomy pre-surgery, aiming to improve preoperative simulation and intraoperative navigation. Methods. We integrated 3D data from preoperative CT scans into Perspectus VR Education software, displayed via HMDs for in-teractive 3D reconstruction of pulmonary structures. This detailed visualization aids in tailored preoperative resection simulations. During RATS, surgeons access these 3D images through Tile-ProTM multi-display for real-time guidance. Results. The VR system enabled precise visualization of pulmonary structures and lesion relations, enhancing surgical safety and accuracy. The HMDs offered true 3D interaction with patient data, facilitating surgical planning. Conclusions. VR sim-ulation with HMDs, akin to a robotic 3D viewer, offers a novel approach to developing robotic surgical skills. Integrated with routine imaging, it improves preoperative planning, safety, and accuracy of anatomical resections. This technology particularly aids in lesion identification in RATS, optimizing surgical outcomes.

Tumor-to-thoracic height ratio as an easy method to predict the feasibility of reduced-port video-assisted thoracic surgery for mediastinal lesions in children: a single-center experience.

In the last few decades, reduced-port video-assisted thoracic surgery (RP-VATS) has been developed to minimize surgical invasiveness. Nevertheless, VATS in children can occasionally be difficult because the lesion occupies a small thoracic cavity, limiting the working space. This study aimed to assess the feasibility of RP-VATS for the resection of mediastinal lesions in children in association with the tumor-to-thoracic height ratio (TTH ratio). We reviewed all patients aged ≤10 years who underwent resection for mediastinal lesions in our institute between January 2008 and August 2022. Patients who underwent diagnostic procedures were excluded from this study. The TTH ratio was calculated as tumor height divided by thoracic height. Seven patients in the RP-VATS group and six in the conventional procedures (multi-portal VATS or open surgery) group were included in this study. The TTH ratio was significantly lower in the RP-VATS group than in the conventional procedures group (median, 26.3% vs. 50.8%; P=0.007). The operating time (P=0.01) and duration of drainage (P=0.003) were significantly shorter and the blood loss (P=0.001) was significantly lower in the RP-VATS group than in the conventional procedures group. After adjusting for age, a lower TTH ratio was significantly associated with the completion of RP-VATS (odds ratio: 0.776; 95% confidence interval: 0.529-0.926; P=0.048). In conclusion, RP-VATS can be performed appropriately in carefully selected cases of pediatric mediastinal lesions. A low TTH ratio may predict the feasibility of RP-VATS. Further studies are warranted to determine the criteria for the indications of RP-VATS in children, so that more children can benefit from RP-VATS.

Distribution and clinical impact of molecular subtypes with dark zone signature of DLBCL in a Japanese real-world study.

The distribution and clinical impact of cell-of-origin (COO) subtypes of diffuse large B-cell lymphoma (DLBCL) outside Western countries remain unknown. Recent literature also suggests that there is an additional COO subtype associated with the germinal center dark zone (DZ) that warrants wider validation to generalize clinical relevance. Here, we assembled a cohort of Japanese patients with untreated DLBCL and determined the refined COO subtypes, which include the DZ signature (DZsig), using the NanoString DLBCL90 assay. To compare the distribution and clinical characteristics of the molecular subtypes, we used a data set from the cohort of British Columbia Cancer (BCC) (n = 804). Through the 1050 patient samples on which DLBCL90 assay was successfully performed in our cohort, 35%, 45%, and 6% of patients were identified to have germinal center B-cell-like (GCB) DLBCL, activated B-cell-like (ABC) DLBCL, and DZsig-positive (DZsigpos) DLBCL, respectively, with the highest prevalence of ABC-DLBCL, differing significantly from the BCC result (P < .001). GCB-DLBCL, ABC-DLBCL, and DZsigpos-DLBCL were associated with 2-year overall survival rates of 88%, 75%, and 66%, respectively (P < .0001), with patients with DZsigpos-DLBCL having the poorest prognosis. In contrast, GCB-DLBCL without DZsig showed excellent outcomes after rituximab-containing immunochemotherapy. DZsigpos-DLBCL was associated with the significant enrichment of tumors with CD10 expression, concurrent MYC/BCL2 expression, and depletion of microenvironmental components (all, P < .05). These results provide evidence of the distinct distribution of clinically relevant molecular subtypes in Japanese DLBCL and that refined COO, as measured by the DLBCL90 assay, is a robust prognostic biomarker that is consistent across geographical areas.

High density and proximity of CD8+ T cells to tumor cells are correlated with better response to nivolumab treatment in metastatic pleural mesothelioma.

BACKGROUND: The efficacy of immune checkpoint inhibitors (ICIs) in pleural mesothelioma has recently been established. The response to ICIs can be predicted by quantitative analysis of cells and their spatial distribution in the tumor microenvironment (TME). However, the detailed composition of the TME in pleural mesothelioma has not been reported. We evaluated the association between the TME and response to ICIs in this cancer. METHODS: A retrospective analysis of 22 pleural mesothelioma patients treated with nivolumab in different centers was performed using surgical specimens. Four patients had a partial response to nivolumab (response group) and 18 patients had stable or progressive disease (nonresponse group). The number of CD4, CD8, FoxP3, CK, and PD-L1 positive cells, cell density, and cell-to-cell distance were analyzed by multiplex immunofluorescence. RESULTS: PD-L1 expression did not differ significantly between the response and nonresponse groups. The density of total T cells and of CD8+ T cells was significantly higher in the response than in the nonresponse group. CD8+ T cells were more clustered and located closer to tumor cells, whereas regulatory T cells were located further from tumor cells in the response than in the nonresponse group. CONCLUSIONS: High density and spatial proximity of CD8+ T cells to tumor cells were associated with better response to nivolumab, whereas the proximity of regulatory T cells to tumor cells was associated with worse response, suggesting that the distinct landscape of the TME could be a potential predictor of ICI efficacy in pleural mesothelioma.

A novel edge-marking method in pleural covering with video-assisted thoracic surgery.

Total pleural covering is implemented to reinforce the visceral pleura with surgical sheets. It has been adopted for diffuse cystic lung diseases such as lymphangioleiomyomatosis to prevent pneumothorax and has achieved good results. The procedure is technically demanding, because it is difficult to cover the entire visceral pleura without disarrangement and jamming of surgical sheets, especially during thoracoscopic surgery, where grasping of a wrong site might happen when unfolding the sheets. Herein, we report a technique to cover the entire pleura with dotted line folded sheets to ease the thoracoscopic procedure. We found that the use of this marking method made the procedure easier, with just a little ingenuity, because marking the edges of sheets with dashed lines clarifies the site that should be grasped, thus preventing the incidence of grasping the wrong part of the sheet. Pleural covering with dotted line folded surgical sheets is a useful method for reduced port thoracoscopic surgery.

Dual-portal robotic-assisted thoracic surgery (DRATS) as a reduced port RATS: early experiences in three institutions in Japan.

Background: Robotic-assisted thoracic surgery (RATS) has gained increasing interest in recent years, with most procedures performed using the conventional multiportal approach. Uniportal RATS (URATS) approaches have recently been reported in the pursuit of minimally invasive procedures. However, URATS requires specific skills. Herein, we introduce dual-portal RATS (DRATS) performed with two incisions. Methods: Data of DRATS procedures performed from December 2022 to May 2023 were retrospectively reviewed. Twenty patients with lung cancer underwent anatomical lung resections via DRATS performed by our group at three institutes. Results: Among 20 cases of planned DRATS for anatomical pulmonary resections, there were no conversions to thoracotomy and no need for extra ports. The mean surgery time was 121±60 minutes and mean console time was 91±47 minutes. The mean intraoperative blood loss volume was 9.6±12.1 g. The mean duration of chest tube drainage and hospital stay were 2±1 and 5±2 days, respectively. The mean numerical rating scale for pain was 2±1 on the first postoperative day, 1±1 on the third day, and 1±1 at discharge. There were no postoperative complications or mortalities. Conclusions: Our primary experience shows that DRATS is safe and feasible for anatomical lung resection. We consider DRATS to be a very good preliminary step in the future transition to URATS.

Fatal case of subdural empyema caused by Campylobacter rectus and Slackia exigua

ABSTRACT We report a fatal subdural empyema caused by Campylobacter rectus in a 66-year-old female who developed acute onset of confusion, dysarthria, and paresis in her left extremities. A CT scan showed hypodensity in a crescentic formation with a mild mid-line shift. She had a bruise on her forehead caused by a fall several days before admission, which initially raised subdural hematoma (SDH) diagnosis, and a burr hole procedure was planned. However, her condition deteriorated on the admission night, and she died before dawn. An autopsy revealed that she had subdural empyema (SDE) caused by Campylobacter rectus and Slackia exigua. Both microorganisms are oral microorganisms that rarely cause extra-oral infection. In our case, head trauma caused a skull bone fracture, and sinus infection might have expanded to the subdural space causing SDE. CT/MRI findings were not typical for either SDH or SDE. Early recognition of subdural empyema and prompt initiation of treatment with antibiotics and surgical drainage is essential for cases of SDE. We present our case and a review of four reported cases.

Parietal pleural small holes found in patients with primary spontaneous pneumothorax associated with relatively mild chest wall flatness: a retrospective study.

Background: During surgery for spontaneous pneumothorax, parietal pleural small holes (PPSHs) are occasionally found around the apex of the intrapleural space; however, this has not been well recognized. Additionally, chest wall flatness is usually observed in patients with primary spontaneous pneumothorax (PSP) and PPSHs. This study aimed to investigate the prevalence of PPSH and evaluate the characteristics of patients with PPSH. We also investigated the degree of chest wall flatness in patients with PPSHs. Methods: We retrospectively reviewed all patients who underwent thoracoscopic surgery for pneumothorax at our department between April 2014 and May 2021. A propensity-matched analysis was used to compare the characteristics of patients with and without PPSH. Results: A total of 490 patients were enrolled in this study. PPSH was found in 45 of 297 (15.2%) patients with PSP and one of 193 (0.5%) patients with secondary pneumothorax. PSP was independently associated with the presence of PPSH after adjusting for age and sex [primary/secondary, odds ratio (OR) =34.3, 95% confidence interval (CI): 4.7-250.9; P<0.001]. Among patients with PSP, the flatness of the chest wall in patients with PPSH was not as severe as that in patients without PPSH {thoracic anteroposterior diameter (APDT) to transverse diameter (TDT) ratio; with PPSH: median =0.517 [interquartile range (IQR) =0.480-0.554] vs. without PPSH: median =0.487 (IQR =0.463-0.529; P=0.031)} after propensity score matching. Conclusions: PPSH is found in a non-negligible proportion of patients with PSP, and patients with PPSHs show a relatively mild flat chest among patients with PSP. Clinicians should be aware of PPSH, and further understanding of this condition may contribute to a better understanding of PSP.

Anatomical segmentectomy under uniportal video-assisted thoracoscopic surgery for early staged non-small cell lung cancer: a case report.

Background: Anatomical segmentectomy has become more and more universal in thoracic surgery because of the increasing detection of pulmonary nodules with ground-glass opacity (GGO), most of which proved early staged non-small cell lung cancer (NSCLC) postoperative. With the advantage of preservation of normal lung tissues, segmentectomy may be performed by surgeons when computed tomography (CT) scan shows pure GGO or multiple GGOs appearing. Especially when the patients with poor cardiopulmonary function or severe comorbidities or in the circumstance of bilateral pulmonary GGOs, segmentectomy can provide opportunities to radically resect all lesions. With the development of minimally invasive surgery technology, uniportal video-assisted thoracoscopic surgery (VATS) has become the regular operative route in many medical centers because it can provide less access trauma, less stress response, less pain, shorter hospital stays, and a lower postoperative complication rate and corresponds well with the idea of "minimally invasive". However, all of the procedures must be performed in one tiny portal, so uniportal VATS anatomical segmentectomy not only needs the skill and patience of surgeons but the effective cooperation of assistants, nurses and anesthetists, and plenty of details must be paid special attention. Case Description: Here we present a video of a patient undergoing S1 segmentectomy of right upper lobectomy (RUL) under uniportal VATS. The chief complaints of the patients was that two pure GGOs in the bilateral upper lobe were found by physical examination for 26 months and he had no symptoms. We performed S1 segmentectomy of RUL under uniportal first time and performed trisegmentectomy of left upper lobectomy (LUL) 3 months later. With routinely follow-up, no evidence of relapse and metastasis disease was found. Conclusions: We think anatomical segmentectomy under uniportal VATS can be a feasible and safe procedure that reduces trauma and has equivalent oncology outcomes to lobectomy in early-stage lung cancer but need a more experienced medical center to perform. Keywords: Uniportal video-assisted thoracoscopic surgery (uniportal VATS); segmentectomy; non-small cell lung cancer (NSCLC); case report.

A novel system for analyzing indocyanine green (ICG) fluorescence spectra enables deeper lung tumor localization during thoracoscopic surgery.

Background: Palpation of tumors during thoracoscopic surgery remains difficult, and identification of deep-seated tumors may be impossible. This preclinical study investigated the usefulness of a novel indocyanine green (ICG) fluorescence spectroscopy system for tumor localization. Methods: ICG was diluted to 5.0×10-2 mg/mL in fetal bovine serum (FBS) and mixed with silicone resin to prepare pseudo-tumors. Sponges of different densities and a porcine lung were placed on top of the pseudo-tumors, which were examined using a novel fluorescence spectroscopy system and a near-infrared (NIR) camera. Spectra were measured for different sponge and lung thicknesses, and the lung spectra were measured during both inflation and deflation. Results: The fluorescence spectroscopy system was able to identify tumors at depths ≥15 mm, while the NIR system was not. The spectroscopy system also detected tumors at greater depths when the density of the intervening material was lower. Depending on the density and thickness of the intervening material, the system could detect spectra as deep as 40 mm for sponges and 30 mm for lungs. Conclusions: This new fluorescence spectroscopy system can be used to identify lung tumors up to a depth of 30 mm in experiments using pseudo-tumors and a porcine lung, which may aid in tumor identification during thoracoscopic surgery.

Preclinical evaluation of thin convex probe endobronchial ultrasound-guided transbronchial needle aspiration for intrapulmonary lesions.

Background: Conventional flexible bronchoscopy has not achieved the high diagnostic yield for intrapulmonary lesions as seen with image-guided transthoracic biopsy. A thin convex probe endobronchial ultrasound bronchoscope (TCP-EBUS) with a 5.9-mm tip was designed to improve peripheral access over conventional EBUS bronchoscopes to facilitate real-time sampling of intrapulmonary lesions under ultrasound guidance. Methods: TCP-EBUS was inserted into the distal airways of ex-vivo human lungs to assess bronchial accessibility relative to clinically available bronchoscopes. The short- (≤1 h) and medium-term (≤10 d) safety of TCP-EBUS insertion and EBUS-guided transbronchial needle aspiration (TBNA) using a 25-gauge needle were evaluated physiologically and radiologically in live pigs. TCP-EBUS-guided TBNA feasibility was assessed in-vivo with pig intrapulmonary pseudo-tumors and ex-vivo with resected human lung cancer specimens. Results: For bronchial accessibility, TCP-EBUS demonstrated greater reach than the 6.6-mm convex probe endobronchial ultrasound (CP-EBUS) in all bronchi, as well as surpassed a 5.5-mm conventional bronchoscope in 63% (131/209) and a 4.8-mm conventional bronchoscope in 27% (57/209) of assessed bronchi. The median bronchial generation and the mean diameter of bronchi TCP-EBUS reached was 4 (range, 3-7) and 3.3±0.7 mm, respectively. No major complications related to TCP-EBUS-guided TBNA in distal airways were observed in the live pigs. Scattered mucosal erythema of the bronchial walls was observed immediately after TCP-EBUS insertion; this self-resolved by day 10. TCP-EBUS could successfully reach and visualize intrapulmonary targets via ultrasound, with no difficulty in needle deployment or sampling. Conclusions: TCP-EBUS has the potential to facilitate safe real-time transbronchial sampling of intrapulmonary lesions in the central and middle lung fields.

Partitioning the lung field based on the depth ratio in three-dimensional space.

Background: To explore the feasibility of the depth ratio method partitioning the lung parenchyma and the depth distribution of lung nodules in pulmonary segmentectomy. Methods: Based on the measurement units, patients were allocated to the chest group, the lobar group, and the symmetrical 3 sectors group. In each unit, the center of the respective bronchial cross-section was set as the starting point (O). Connecting the O point with the center of the lesion (A) and extending to the endpoint (B) on the pleural, the radial line (OB) was trisected to divide the outer, middle, and inner regions. The depth ratio and relevant regional distribution were simultaneously verified using 2-dimensional (2D) coronal, sagittal, and axial computed tomography images and 3-dimensional (3D) reconstruction images. Results: Two hundred and nine patients were included in this study. The median age was 53 (IQR, 44.5-62) years and 64 were males. The intra-group consistency of the depth ratio region partition was 100%. The consistency of the inter-group region partition differed among the three groups (Kappa values 0.511, 0.517, and 0.923). The chest group, lobar group, and symmetrical 3 sectors group had 69.4%, 26.3%, and 4.8% mediastinum disturbance, respectively (P<0.001). Conclusions: The depth ratio method in the symmetrical 3 sectors of the lung maximally eliminated the disturbance of the mediastinal structures and more accurately trisected the lung parenchymal in 3D space. Sublobar resection based on subsegments strategy is feasible for outer 2/3 pulmonary nodules when depth ratio is used as the measurement method.

Endobronchial ultrasound-guided bipolar radiofrequency ablation for lung cancer: A first-in-human clinical trial.

OBJECTIVE: Percutaneous radiofrequency ablation (RFA) is a therapeutic option for lung tumors. However, percutaneous approaches have limited access to central lung regions and a relatively high complication rate. To overcome these limitations, a needle-type bipolar RFA device compatible with an endobronchial ultrasound (EBUS) bronchoscope was developed. The aim of this pilot study was to evaluate the immediate-term safety and ablation zone of lung tumor EBUS-guided RFA. METHODS: This was an ablate-and-resect study in patients scheduled for surgical resection of clinical stage I or II lung cancer or metastatic lung lesions ≥1 cm that were accessible using an EBUS bronchoscope. The RFA electrodes were placed within the lung nodule using EBUS guidance followed by ablation. Bronchoscopy and contrast-enhanced computed tomography were performed to evaluate for post-RFA complications. The resected lung underwent pathological assessment to characterize the ablation zone. RESULTS: A total of 5 primary lung cancers were ablated in 5 separate patients; no patients with metastatic lesions were recruited. For a total energy of 4 kJ (n = 3), 6 kJ (n = 1), and 8 kJ (n = 1) delivered, the ablation time was a mean of 13.8 (range, 10.3-16.0) minutes, 8.4 minutes, and 15.6 minutes, respectively, and the maximum ablation diameter was a mean of 1.8 (range, 1.3-2.1) cm, 2.7 cm, and 2.6 cm, respectively. No immediate post-RFA complications were observed. CONCLUSIONS: EBUS-guided bipolar RFA can ablate lung tumors using real-time ultrasound guidance. EBUS-guided RFA might ultimately represent a minimally invasive therapy for lung cancer in patients unable to tolerate surgery. Longer-term safety will need to be evaluated.

Presurgical assessment of flow variability in an azygos vein aneurysm using 4D-flow MRI.

Azygos vein aneurysm (AVA) is necessary to prevent pulmonary embolism due to the outflow of a thrombus or rupture of the aneurysm. However, there is no established modality to assess the properties of AVA. Time-resolved three-dimensional phase-contrast magnetic resonance imaging (4D-flow MRI) has been used to examine the hemodynamics in various fields. We report a case of AVA to evaluate the flow variability and adhesions of surrounding tissues using 4D-flow MRI. The findings of the study suggested aneurysm turbulence and the absence of thrombi. The cine image, which showed a sliding wall synchronized to the heartbeat, indicated no adhesion to the superior vena cava. Based on these results, the thoracoscopic approach was deemed possible preoperatively. Thoracoscopic AVA resection was performed, and the postoperative course was uneventful. This study documented the utility of 4D-flow MRI for a detailed evaluation of AVA.

Thymoma-Related Stiff-Person Syndrome with Successfully Treated by Surgery.

INTRODUCTION: Stiff-person syndrome (SPS) is a rare autoimmune neurological disorder. Paraneoplastic SPS associated with malignant tumors such as thymoma occurs in approximately 5% of all SPS cases. We present a rare case of thymoma accompanied by SPS successfully treated using surgery. PRESENTATION OF CASE: A 26-year-old woman presented with lower limbs convulsions and gait disturbance and complained of leg pain. Cerebrospinal fluid and blood test results showed a high level of anti-glutamic acid decarboxylase (GAD) antibodies. Computed tomography showed anterior mediastinal tumor suggestive of a thymoma. She underwent extended thymectomy, and her symptoms gradually improved after surgery. No evidence of recurrent thymoma and SPS has been observed over 44 months. CONCLUSION: Surgical treatment would be effective for patients with SPS and thymoma.