Polysplenia syndrome is an embryological disorder whereby the usual left-right asymmetry of thoracic and abdominal viscera fails to develop. It is a rare entity, estimated to occur at a frequency of 1 in 40,000, and is often associated with cardiac and biliary abnormalities. More than 75% of patients die before the age of 5 years, and even in the absence of cardiac anomalies, only 5%-10% of patients are expected to survive into adulthood without complications. Although polysplenia syndrome encompasses a wide range of anatomic abnormalities, there is no single pathognomonic feature. Hence, the prognosis of patients with polysplenia depends on their anatomy, thus necessitating radiology in their management. Here we present a case of a 56-year-old man with polysplenia syndrome and situs inversus totalis. This presentation is atypical because polysplenia is usually considered a form of situs ambiguus, and cases with situs inversus totalis are exceedingly rare. Also noted in our patient are variations in the great vessels, including aortic arch branches and the venae cavae which are features not typically associated with either polysplenia syndrome or situs inversus totalis. The patient is healthy and asymptomatic at baseline, with his diagnosis being made incidentally. Our case report is the first to describe this unique combination of cardiothoracic and cardiovascular anatomy. It also emphasizes the importance of radiologists in caring for patients with laterality defects. As these disorders are uncommon, more data on their anatomic variations may help provide better medical care to this patient population.

Intrahepatic interruption of the inferior vena cava (IVC) with continued hemizygous is a very rare abnormality and sometimes it may be accompanied by other cardiovascular abnormalities. Continuation of the hemizygous vein draining into the right atrium through the left superior vena cava (LSVC) is much rarer. In this paper, we have presented a patient who had simultaneous IVC interrupted with persistent LSVC and suffered from Atrioventricular nodal reentrant tachycardia (AVNRT). Finally, radiofrequencies (RF) catheter ablation for AVNRT was successfully performed through a left subclavian vein access.

UNASSIGNED: Segmental aplasia of the caudal vena cava (CVC) with azygos continuation is a congenital malformation macroscopically described in mammals including humans, dogs, and rodents. It is usually detected as an incidental finding and the final diagnosis is reached by computed tomography (CT), fluoroscopy, or post-mortem dissection.
UNASSIGNED: A 3-year-old guinea pig (Cavia porcellus) presented with subacute dyspnea. A computed tomographic examination was performed for the evaluation of subtle pulmonary changes previously suspected on conventional radiography, and a segmental aplasia of the CVC with azygos continuation was identified as an incidental finding.
UNASSIGNED: According to database negative results, this is the first report describing a segmental aplasia of the CVC and azygos continuation in a guinea pig by CT.

BACKGROUND: The malposition of central venous catheters (CVCs) may lead to vascular damage, perforation, and even mediastinal injury. The malposition of CVC from the right subclavian vein into the azygos vein is extremely rare. Here, we report a patient with CVC malposition into the azygos vein via the right subclavian vein. We conduct a comprehensive review of the anatomical structure of the azygos vein and the manifestations associated with azygos vein malposition. Additionally, we explore the resolution of repositioning the catheter into the superior vena cava by carefully withdrawing a specific length of the catheter.
METHODS: A 79-year-old female presented to our department with symptoms of complete intestinal obstruction. A double-lumen CVC was inserted via the right subclavian vein to facilitate total parenteral nutrition. Due to the slow onset of sedative medications during surgery, the anesthetist erroneously believed that the CVC had penetrated the superior vena cava, leading to the premature removal of the CVC. Postoperative contrast-enhanced computed tomography of the chest confirmed that the central venous catheter had not penetrated the superior vena cava but malpositioned into the azygos vein. The patient was discharged 15 days after surgery without any complications.
CONCLUSIONS: CVC malposition into the azygos vein is extremely rare. Clinical practitioners should be vigilant regarding this form of catheter misplacement. Ensuring the accurate positioning of the CVC before each infusion is crucial. Utilizing chest X-rays in both frontal and lateral views, as well as chest computed tomography, can aid in confirming the presence of catheter misplacement.

A 63-year-old woman was admitted to our department for the investigation of superior vena cava (SVC) syndrome. Computed tomography revealed an azygos tumor extending into the SVC. Video-assisted thoracic surgery (VATS) was performed to remove the distal end of the azygos vein in the left lateral position, followed by complete resection of the entire tumor under median sternotomy in the supine position. The histological diagnosis was a primary angiosarcoma of the azygos vein. The patient was discharged without any complications and is now alive and tumor-free 24 months after surgery. In addition, contrast-enhanced computed tomography revealed no graft occlusion in the two reconstructed brachiocephalic veins. Thoracoscopic surgery in the lateral position is useful for safe and reliable complete resection of a tumor arising from the azygos vein.

The azygos venous system is a crucial conduit of the posterior thorax and potentially vital collateral pathway. However, it is often overlooked clinically and radiologically. This pictorial essay reviews the normal azygos venous anatomy and CT findings of congenital variations and structural changes associated with acquired pathologies.
기정맥계는 후방 흉부의 중요한 부속 정맥이며 측부순환으로서 중대한 역할을 한다. 그러나, 그 중요성에도 불구하고 임상적 혹은 영상의학적으로 종종 간과된다. 본 임상화보에서는, 기정맥계의 정상 해부학에 대해 알아보고, 기정맥계에서 볼 수 있는 다양한 선천 변이와 후천적 질환에 따른 구조 변화의 CT 소견에 대하여 검토하고자 한다.

Intraluminal tumor in the azygos vein is a rare disease that can cause superior vena cava (SVC) syndrome. Radiotherapy and endovascular stenting with or without chemotherapy are reported to have a high clinical success rate for the management of SVC syndrome with malignancy, but a poor survival rate. Here, we report a 69-year-old man who presented with swelling of the face and upper extremities, who was diagnosed with SVC syndrome caused by an intraluminal tumor in the azygos vein. Enhanced chest computed tomography revealed an intraluminal mass with a filling defect from the azygos vein to the SVC, with no extravascular extension or dissemination of the primary tumor. Surgical resection of the mass en bloc with the azygos vein and SVC reconstruction was performed. A poorly differentiated carcinoma was diagnosed on postoperative pathological evaluation. Twelve months after resection, the patient was well with no signs of recurrent disease. This case highlights that surgical resection should be considered as a treatment of choice for the management of SVC syndrome caused by an intraluminal malignancy in the azygos vein.

High-speed motor vehicle collisions (MVCs) often result in severe musculoskeletal, neurological, and vascular injuries. Among these, azygos vein pseudoaneurysms (AVPs) are a rare and potentially life-threatening vascular complication. Our case study highlights an instance of an AVP arising from a high-velocity MVC, underscoring their critical significance in trauma scenarios. Additionally, this report delves into the complexities of managing AVPs, both traumatic and idiopathic, emphasizing the urgent need for intervention and the intricacies of their treatment.

Chronic venous insufficiency, caused by inferior vena cava occlusion, can lead to thromboembolic complications and tissue loss. We present two cases of azygos vein stenting (AVS) in which vena cava recanalization techniques were exhausted. In the first case, the left iliac vein and vena cava were recanalized and stented; however, the right iliac vein had been previously resected and required AVS. Conventional recanalization attempts from the right and left iliac systems failed in the second patient with congenital inferior vena cava occlusion; therefore, AVS was chosen to establish in-line drainage.

Since the first successful repair of esophageal atresia/tracheoesophageal fistula (EA-TEF) was performed approximately 8 decades ago, surgeons have made considerable technical advances in solving intraoperative surgical challenges and reducing postoperative complications. According to some surgeons, preserving the Azygos vein makes this modification attractive. This study aimed to evaluate the benefits of preserving the Azygos vein during surgery for esophageal atresia with tracheoesophageal fistula and to highlight its advantages in reducing anastomotic leak, stricture, and other postoperative outcomes. This prospective comparative series was conducted between April 2020 and April 2023. The study included all newborns with EA-TEF eligible for primary repair. Patients were randomized to either Group A or B. Group A underwent Azygos vein preservation, whereas the remaining patients (Group B) underwent Azygos vein disconnection. Sixty-four patients were included in this study. Thirty-two patients (Group A) underwent Azygos vein preservation during EA-TEF repair, and the remaining thirty-two patients (Group B) underwent Azygos vein ligation and disconnection. Both groups were comparable in terms of demographics, clinical data, and operative findings (P > 0.05). Pneumonitis occurred in 4 patients in Group A and 16 patients in Group B. Anastomotic leaks occurred in two (6.2%) patients in Group A and six (18.7%) patients in Group B. There were two deaths in Group A and six deaths in Group B, with a significant difference between the two groups (P = 0.0485). Preserving the Azygos vein during esophageal atresia repair reduces the occurrence of postoperative pneumonia, leakage, and stenosis, and decreases postoperative mortality. Therefore, we declare that this modification is a significant and valuable addition to the current surgical procedures.