Pilot study on the use of acoustic radiation force impulse imaging in the staging of cystic fibrosis associated liver disease

Background: Acoustic radiation force impulse (ARFI) is a novel technique for the measurement of hepatic stiffness, which could be valuable in clinical follow-up of patients affected by cystic fibrosis liver disease (CFLD). Methods: Seventy-five patients with suspected CFLD (35 males) underwent clinical and ultrasonographic evaluations, liver and pulmonary function tests, ARFI investigation, and upper gastrointestinal endoscopy. Ten ARFI measurements were taken at the deep right hepatic lobe to compute median values of Shear Wave Velocity (SWV) for each individual. Results: SWV increased progressively from 1.02 m/s (95%, Confidence Interval, CI, 0.92-1.126) in patients with no evidence of CFLD at ultrasonography (N=16), to 1.12 (95%CI 1.049-1.19) in patients with CFLD and no signs of portal hypertension (PHT, N=23), and to 1.25 (95%CI 1.14-1.358) in those with CFLD and signs of PHT (N=28). SWV was 1.63 (95%CI 1.26-1.99) in patients with oesophageal varices (N=8) (p<0.0001). Conclusions: ARFI may represent an easy, fast and non-invasive tool for the clinical follow-up of patients with cystic fibrosis associated liver disease. (C) 2012 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.