Journal ArticleDOI
Where there is blood, there is a way: unusual collateral vessels in superior and inferior vena cava obstruction.
TLDR
An understanding of these unusual collateral pathways is essential in a patient with caval occlusion who presents with signs and symptoms of a right-to-left shunt or has unusual enhancing lesions in the liver.Abstract:
Obstruction of the superior vena cava (SVC) or inferior vena cava (IVC) is most commonly an acquired condition, typically caused by malignancy, benign conditions such as mediastinal fibrosis, and iatrogenic causes such as venous catheterization. In the event of chronic occlusion, collateral pathways must develop to maintain venous drainage. The major collateral pathways seen with SVC or IVC obstruction are well described and include the azygos-hemiazygos, internal and external mammary, lateral thoracic, and vertebral pathways. In addition, several unusual collateral pathways may be seen with SVC or IVC obstruction; these include systemic-to-pulmonary venous, cavoportal, and intrahepatic collateral pathways. In patients with systemic-to-pulmonary venous collateral vessels, the systemic veins drain directly into the left side of the heart, resulting in a right-to-left shunt. The collateral veins consist of mediastinal connections between the innominate veins and the superior pulmonary veins through bronchial venous plexuses around the airways, hilar vessels, and pleura. The cavoportal collateral pathways consist of collateral formation between the SVC or IVC and a tributary to the portal system. They include the caval-superficial-umbilical-portal pathway, caval-mammary-phrenic-hepatic capsule-portal pathway, caval-mesenteric-portal pathway, caval-renal-portal pathway, caval-retroperitoneal-portal pathway, and intrahepatic cavoportal pathway. These types of collateral pathways may result in unusual enhancement patterns in the liver. An understanding of these unusual collateral pathways is essential in a patient with caval occlusion who presents with signs and symptoms of a right-to-left shunt or has unusual enhancing lesions in the liver.read more
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Journal ArticleDOI
Learning from the pulmonary veins.
Diego Varona Porres,Oscar Persiva Morenza,Esther Pallisa,Alberto Roque,Jorge Andreu,Manel Martínez +5 more
TL;DR: The pulmonary veins can act as conduits for collateral circulation in cases of obstruction of the superior vena cava, and Multidetector CT is an excellent modality for imaging evaluation of the pulmonary veins, even when the examination is not specifically tailored for their assessment.
Journal ArticleDOI
Collateral Pathways in Portal Hypertension
TL;DR: The objective of this review is to illustrate the various PSCV and portoportal collateral vein pathways pertinent to portal hypertension in liver cirrhosis and EHPVO.
Journal ArticleDOI
The multiple dimensions of Platypnea-Orthodeoxia syndrome: A review.
TL;DR: The etiology and pathophysiology of POS is reviewed and the diagnostic algorithms and treatment modalities available for early diagnosis and prompt treatment of patients presenting with symptoms of platypnea and/or orthodeoxia are summarized.
Journal ArticleDOI
Malignant Venous Obstruction: Superior Vena Cava Syndrome and Beyond.
TL;DR: The pertinent literature regarding the clinical presentation, workup, and endovascular management of malignant central venous obstruction syndromes, with directed attention to superior vena cava syndrome and inferior venacava syndrome, will be reviewed in this article.
Journal ArticleDOI
Gastric varices: Classification, endoscopic and ultrasonographic management
TL;DR: In this review, new treatment modalities in the form of endoscopic treatment options and interventional radiological procedures have been discussed besides discussion on classification and pathophysiology of GV.
References
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Journal ArticleDOI
Congenital Hepatic Shunts
Carmen Gallego,María Miralles,Carlos Enrique Montenegro Marín,Purificación Muyor,Gabino González,Enrique García-Hidalgo +5 more
TL;DR: The radiologic findings in 42 children with infantile hepatic hemangioma, vascular malformations, or infradiaphragmatic total anomalous pulmonary venous return (TAPVR) associated with congenital vascular shunting were retrospectively reviewed.
Journal ArticleDOI
Functional anatomy of the porta-systemic communications.
TL;DR: The findings indicate that the deep pathways in the pelvis, abdomen and thorax are normally patent and are of greater importance than the anterior parietal ones.
Journal ArticleDOI
Unusual Hemodynamics and Pseudolesions of the Noncirrhotic Liver at CT
Kengo Yoshimitsu,Hiroshi Honda,Toshiro Kuroiwa,Hiroyuki Irie,Hitoshi Aibe,Kenji Shinozaki,Kouji Masuda +6 more
TL;DR: Radiologists need to understand the underlying mechanism of these pseudolesions to better recognize the wide range of their appearances at CT, which vary from nonenhanced low-attenuation areas to well-enhanced high-attenuated areas, depending on the amount and timing of the inflow.