Non-invasive diagnosis of portal hypertension by acoustic radiation force impulse (ARFI) imaging of the liver and spleen in patients with compensated chronic liver disease

• Grant number: 12/12403-0
• Support Opportunities: Scholarships abroad - Research
• Start date: January 14, 2013
• End date: January 13, 2014
• Field of knowledge: Health Sciences - Medicine - Medical Clinics
• Principal Investigator: Fernanda Fernandes Souza
• Grantee: Fernanda Fernandes Souza
• Host Investigator: Guadalupe Garcia-Tsao
• Host Institution: Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da USP (HCMRP). Ribeirão Preto , SP, Brazil
• Institution abroad: Yale University, United States

Abstract

SummaryPortal hypertension plays a central role in the pathophysiology and clinical presentation of patients with cirrhosis. Most of the complications that account for the high morbidity and mortality of cirrhosis are due to portal hypertension. The best available measure of portal hypertension is the hepatic venous pressure gradient (HVPG). HVPG represents the single most valuable prognostic indicator in the management of patients with cirrhosis and portal hypertension. HVPG >10 mmHg has been shown to accurately identify those patients at higher risk of developing varices, clinical decompensation and hepatocellular carcinoma (HCC). Consequently, HVPG >10 mmHg defines "clinically significant portal hypertension". Although, HVPG provides important information, it requires a relatively difficult invasive procedure that limits its use in routine clinical practice (need of local expertise, invasive nature and a global risk of death of 1/1000 procedures). Thus, a number of alternative non-invasive procedures have been intensively investigated in recent years. In this context, a new, non-invasive, imaging technology named ARFI (from Acoustic Radiation Force Impulse) has been proposed as an alternative method to evaluate cirrhosis through the assessment of tissue elasticity. ARFI imaging is essentially an ultrasound technique in which shear wave velocity is evaluated to assess the elastic properties of target tissues. The liver stiffness (LS) and spleen stiffness (SS) evaluation by ARFI can represent a useful diagnostic parameter of portal hypertension. The correlation between LS and SS measured by ARFI, HVPG, and its potential clinical implications are unknown. Thus, the aim of this study is to evaluate the correlation between spleen and liver stiffness (as measured by ARFI imaging) and portal pressure (as determined by HVPG), as well as evaluate correlation between LS with liver fibrosis (determined by liver biopsy) in patients with compensated chronic liver disease.