A 50-year-old female patient presented with the incidental finding of an anterior mediastinal mass on chest radiography during a routine health examination in October 2020. No related subjective symptoms were reported and the physical examination showed no abnormalities. Contrast-enhanced computerized tomography (CT) of the chest showed a 4.8 × 4.6 cm anterior mediastinal mass with significant homogenous enhancement after injection of the contrast (mean CT values before and after contrast injection were 38 and 115 HU, respectively), suggesting a diagnosis of Castleman's disease, but not excluding thymoma ().\nThe patient underwent surgical resection of the anterior mediastinal mass under a thoracoscopic approach. After the intubation of the single lumen tube with a bronchial obstruction balloon, single lung ventilation on the contralateral side was performed under general anesthesia. The patient was placed in the lateral position with a retroversion of 30°. The operation was performed via a single-utility port: the endoscopic port was a 1-cm incision at the 6th intercostal space in the midclavicular line, and the utility port was a 3-cm incision at the 4th intercostal space along the anterior axillary line. Intraoperatively, the anterior mediastinal mass was determined to be an aneurysm originating from the left innominate vein. Through careful surgical manipulations and adequate exposure of the operative field, the root of the aneurysm was fully dissected and ligated, and then the root vessel was divided with a cutter closure (). Postoperative pathology confirmed the diagnosis of left innominate vein aneurysm. The patient experienced an uneventful postoperative course. The thoracic drainage tube was removed on postoperative day 1 after chest X-ray imaging showed complete re-expansion of the lung, with no obvious pneumothorax or hydrothorax. She was discharged from the hospital on postoperative day 2. At her 6-month follow-up, the patient did not report any specific discomfort.
A 52-year-old man was admitted to our hospital for mediastinal mass found incidentally in health examination. He had no special disease history or any symptoms. No face or upper extremity edema was found in physical examination. Enhanced chest computer tomography (CT) showed a size of 5.6*4.3 cm mass in anterior mediastinum, which was enhanced in the artery phase (Fig. ), and it had no clear boundary with left innominate vein and SVC. The CT report suggested high possibility of thymoma. Echocardiographic examination did not reveal any abnormality. Thymoma was diagnosed and he received operation in our hospital through median sternotomy on July 2019. During the operation, a dark red and saccular mass was found in anterior mediastinum with slight pulsation. The mass had no clear boundary with left innominate vein and further exploration revealed they were connected with each other. The membrane of the mass seemed to be very thin and easily bled when touched. Left innominate venous aneurysm with part of SVC involved was highly suspected.\nThe venous aneurysm was resected with the proximal and distal end of the left innominate vein blocked (Fig. ). However, the majority of the left innominate vein wall was involved and only a little part of vessel wall was left after the venous aneurysm was resected, which made the reconstruction of the left innominate vein necessary. Because of the misdiagnosis and lack of abundant preoperative preparation, we decided to take pericardium as material for repairment and reconstruction. We first resected the involved part of SVC with it blocked, and repaired it with a small piece of pericardium. The SVC was unblocked immediately after repairment was finished. Then we took a large piece of pericardium and wrapped it around a needle tube, suturing the two sides to make it a tube in shape with the smooth surface inside (Fig. ). The tube was first anastomosed to the distal end of the left innominate vein. Then we blocked the SVC again and opened a small hole in the side wall and anastomosed the other side of the tube with SVC. The reconstructed left innominate vein and SVC seemed patent and firm (Fig. ). Low molecular heparin was used once per day just for routine anticoagulation after surgery. The patient had an uneventful postoperative course and was discharged 6 days after surgery. He did not take anticoagulant drugs after discharge and was satisfied with the treatment therapy. The pathological diagnosis was mediastinal hemangioma. The patient kept in good condition on the last follow up date of December 2019.