title: Acquired portosystemic collaterals: anatomy and imaging.
abstract: Portosystemic shunts are enlarged vessels that form collateral pathological pathways between the splanchnic circulation and the systemic circulation. Although their causes are multifactorial, portosystemic shunts all have one mechanism in common-increased portal venous pressure, which diverts the blood flow from the gastrointestinal tract to the systemic circulation. Congenital and acquired collateral pathways have both been described in the literature. The aim of this pictorial essay was to discuss the distinct anatomic and imaging features of portosystemic shunts, as well as to provide a robust method of differentiating between acquired portosystemic shunts and similar pathologies, through the use of illustrations and schematic drawings. Imaging of portosystemic shunts provides subclinical markers of increased portal venous pressure. Therefore, radiologists play a crucial role in the identification of portosystemic shunts. Early detection of portosystemic shunts can allow ample time to perform endovascular shunt operations, which can relieve portal hypertension and prevent acute or chronic complications in at-risk patient populations.
authors: PhD, Radiologist and Physician Assistant at the Instituto de Medicina Integral Professor Fernando Figueira de Pernambuco (IMIP), Maximagem, Centro Diagnóstico Lucilo Ávila Júnior, and Safelaudos, Recife, PE, Brazil.
authors: Andréa Farias de Melo
authors: AF
authors: Leite
authors: MD, Radiology Resident at the Instituto de Medicina Integral Professor Fernando Figueira de Pernambuco (IMIP), Recife, PE, Brazil.
authors: Américo
authors: A
authors: Mota
authors: PhD, Professor in the Department of Radiology of the Universidade de Fortaleza (Unifor), Fortaleza, CE, Brazil.
authors: Francisco Abaeté
authors: FA
authors: Chagas-Neto
authors: PhD, Pediatric Radiologist and Attending Physician at the Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo (FMRP-USP), Ribeirão Preto, SP, Brazil.
authors: Sara Reis
authors: SR
authors: Teixeira
authors: PhD, Professor in the Division of Radiology of the Department of Clinical Medicine at the Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo (FMRP-USP), Ribeirão Preto, SP, Brazil.
authors: Jorge
authors: J
authors: Elias Junior
authors: PhD, Professor in the Division of Radiology of the Department of Clinical Medicine at the Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo (FMRP-USP), Ribeirão Preto, SP, Brazil.
authors: Valdair Francisco
authors: VF
authors: Muglia
keywords: Collateral circulation; Hypertension, portal/complications; Splanchnic circulation