A 52-year-old male patient was admitted to the hospital due to an irritating cough for more than 1 month. He had no recent history of chest trauma surgery or respiratory diseases. A chest CT scan showed anterior mediastinal space, and showed differential diagnosis of teratoma, thymoma and lymphomas, in order to clarify the relationship between the space-occupying lesions and blood vessels and surrounding tissues, a chest-enhanced CT examination was performed. After intravenous injection of contrast medium, a dual-phase scan was performed. It was found that there was a localized aneurysm-like expansion in the left brachiocephalic vein and its diameter was 5.2 cm with the smooth edge (Fig. ), which confirmed the diagnosis of venous aneurysm. After careful evaluation of the patient, surgery was performed.\nA median sternum incision was selected in the surgery. During the operation, a huge aneurysm is found to be located in front of the left brachiocephalic vein. The aneurysm and surrounding tissues were carefully separated to prevent uncontrollable bleeding during the process, and to mechanical damage caused by extracorporeal circulation. We first performed heparinization of the whole body blood, and blocked both ends of the brachiocephalic vein, separated the fibrous membrane of the venous blood vessel, and found that the aneurysm wall was thin. The aneurysm was cystic expansion, and there as a larger aneurysm neck connected to it. After the aneurysm was removed, a double-layer continuous suture with 5–0 prolene thread was used to suture the brachiocephalic vein. We paid attention to the shape of the normal brachiocephalic vein during the suture process. To prevent vascular distortion and lumen stenosis, we carefully loosened the blocking bands at both ends before knotting, determined the shape of the formed blood vessel, and expelled the possible air (Fig. ). After confirming that there is no obvious active bleeding, heparin was neutralized with protamine, and the operation ended after the sternum is fixed by the wire.\nThe mediastinal drainage tube was removed on the third day after the operation, and the patient was discharged from the hospital 2 days later. Postoperative pathology showed that the specimen was thinned venous wall tissue (Fig. ). He was followed up for 6 months, and there was no obvious abnormality in the chest enhanced CT, with good recovery.
A 58 years-old man presented at our emergency room with fever, cough and left thoracic pain. His past medical history was unremarkable. Blood test showed WBC and C-reactive protein elevation. He had started antibiotics therapy and, given the persistence of symptoms, CT scan was performed showing lower left pneumonia. Incidentally, a 2.5 cm mass was found in the upper anterior mediastinum, with positive contrast enhancement and a 5 mm vessel arising from left brachio-cephalic vein (, ). Because of size and position fine needle aspiration nor anterior mediastinotomy were performed. Radiologic features were consistent with thymoma that usually appears as an ovoid or lobulated, smooth, well-marginated mass, projecting over the mediastinum typically protruding unilaterally, therefore patient underwent (1) neurologic evaluation that excluded myasthenia (2) PET/CT scan that showed the absence of any pathological uptake. However, thymoma was felt to remain a diagnostic possibility and patient was referred for radical surgery, with particular attention to abnormal vascularization. He underwent left thoracoscopy and, in spite of extreme attention, during pleural dissection between mediastinum and sternum, a sudden massive bleeding occurred (about 1,500 cc) requiring emergency conversion to median sternotomy. It was then clear that the bleeding came from tumor and not from brachiocephalic vein or its branches, as initially thought. After controlling the bleeding, we removed the mass but it was necessary to sacrifice the left laryngeal nerve.\nIntra-operative emergency required significant blood transfusions and precautionary transfer in intensive care for 24 h. The patient eventually made a complete recovery. We only recorded transitory dysphonia as in case of laryngeal nerve paralysis. At specimen analysis, the cut surface seemed to have some fresh blood and the soft tissue was taupe with multifocal thrombosis in various stages of organization up to phlebolithes. Histopathologically, it was diagnosed a residual thymic tissue surrounded by lipomatous hyperplasia with venous malformation consisting essentially of a large number of dilated vessels with a single layer of endothelial cells with no signs of atypia or mitosis. Most of the channels contained red blood cells in the cavity. Margins were free. Definitive histology was a 7 cm fatty specimen enclosing a 2.5 cm in size mass diagnostic for residual thymus associated with venous vascular malformation (ISSVA classification, 2008).