Ultrasound hepatic elastography with decaying signal technology allows assessing the degree of steatosis and dynamic monitoring of the effectiveness of NAFLD treatment

The purpose of the research is to study the informativeness of the technology of Controlled Attenuation Parameter (CAP) in Shear Wave Elastography (SWE) in determining the degree of severity of liver steatosis depending on the elastometric quantitative values of liver fibrosis in a one-time study in a given volume of parenchima liver in patients with non-alcoholic fatty liver disease (NAFLD). Materials and methods of research. The study included 169 patients with NHTSA between the ages of 19 and 81, the average age was 41.7 ±11.3 years, examined in the “City Clinical Hospital No. 1” of the Ministry of Health, Chuvashia (Cheboksary, Russia). Patients with functional disorders of bile evacuation (n= 72) were the first group; the 2nd group were the patients with liver steatosis without manifestations of liver fibrosis (n = 28); the 3rd contained the patients with cirrhosis of the liver (n = 25); patients with chronic viral hepatitis B and C (n= 44) were in the 4 th  group. All patients were screened with ultrasonic shear wave elastography with elastometry in one-dimensional (TE) (FibroScan 502 TOUCH, France) and two dimensional (2DSWE) modes (Aixplorer, Supersonic Imagine, France). Elastometry (kPa) and steatometry (dB/m) were completed simultaneously within the same volume of the analyzed liver tissue with two sensing devices of “FibroScan 502 TOUCH”. The statistical processing was carried out with the help of IBM SPSS Statistics 10.0. The results are reflected in the form of median (Me), minimum (min), maximum (max) and medium (Emean) values, standard deviation (SD) of Jung’s elasticity module. Correlational analysis of the received values of parameters F and S was made with the descriptive method of Bland-Altman and the method of Spearman. Results and discussion. The average quantitative values of the severity of liver steatosis in patients with cirrhosis of liver had reliably lower values (234.5±62.1 dB/m) than in those suffering from steatosis of the liver without fibrosis (347.5±37.6 dB/m) and patients with chronic viral hepatitis (245.9±57.3dB/m, p lt; 0.001). The values of fibrosis in the same amount of the tested liver tissue with liver cirrhosis (45.5± 22.3 kP) were higher than similar rates in the other groups of patients with NAFLD (p lt; 0.001). Diagnostic informational content of the method of controlled ultrasound attenuation in establishing the degree of manifestation of liver steatosis had a higher specificity with II degree of liver steatosis (99.29% with a sensitivity of 84.92%). The results of the study allow us to recommend ultrasound elastography with the technology of controlled ultrasound attenuation to determine the severity of liver steatosis for both primary diagnosis and for dynamic monitoring of the liver condition of patients with NAFLD.