Ultraschall Med 2016; 37 - PS2_07
DOI: 10.1055/s-0036-1587830

A new diagnosis tool for the evaluation of liver fibrosis: Parametric Arrival Time imaging (PAT)

R Lupusoru 1, I Sporea 1, A Popescu 1, R Sirli 1, M Danila 1, T Moga 1, F Bende 1
  • 1University of Medicine and Pharmacy "Victor Babes", Gastroenterology and Hepatology, Timisoara, Romania

Introduction: Liver biopsy is the “gold standard” method for staging liver fibrosis, but it's an invasive procedure and is associated with risk of some complications. There are also noninvasive techniques for assessment of liver fibrosis such as elastography and biological tests, but these techniques can fail or generate false measurements depending on subjects conditions: food intake, ascites, obesity, etc.

The aim of this study is to determine whether liver fibrosis can be evaluated using the parametric arrival time imaging (PAT) using contrast enhanced ultrasonography (CEUS).

Material and method: Ultrasonography was performed using the LOGIQ E9 (GE Healthcare, Chalfont St. Giles-UK) system. CEUS using SonoVue as contrast was performed in each subject. Liver scanning during the first 30 s following the injection of contrast agent through the cubital vein were saved as raw data on hard disk. The examination was performed with the patients in left lateral position with the right arm elevated above the head and the patients were instructed to hold their breath for some seconds. Images showing liver parenchyma and the right kidney in a single screen were used for analysis. Following ultrasonography, parametric imaging was performed using the proprietary image analysis software of the ultrasound system. A parametric color scale was used: red-first 5 seconds, yellow 5 – 10 seconds, green 10 – 15 seconds, blue 15 – 20 seconds, purple 20 – 25 seconds, brown 25 – 30 seconds.

Results: A ratio of the arrival parametric time was calculated between the kidney and the liver. Previous studies showed that, the faster the contrast arrives in the liver as compared with the kidney, the higher is the severity of fibrosis. This ratio is compared with liver stiffness assessed by Transient Elastography (performed before the CEUS examination).

Conclusion: Our preliminary study on 10 patients showed that the method is feasible, but more patients are needed to draw a conclusion.