Noninvasive Assessment of HCV Patients Using Ultrasound Elastography

*Monica Lupsor-Platon, Teodora Serban and Alexandra Iulia Silion*

#### **Abstract**

Among patients with chronic hepatitis C (CHC) infection, extensive research showed that fibrosis progression is a proper surrogate marker for advanced liver disease, eventually leading to dramatic endpoints such as cirrhosis and hepatocellular carcinoma. Therefore, there is growing interest in the use of noninvasive methods for fibrosis assessment in order to replace liver biopsy (LB) in clinical practice and provide optimal risk stratification. Elastographic techniques, such as Vibration Controlled Transient Elastography (VCTE), point-shear wave elastography (p-SWE), and 2D-SWE have shown promising results in this regard, with excellent performance in diagnosing hepatic cirrhosis, and great accuracy for steatosis detection through the Controlled Attenuation Parameter embedded on the VCTE device. In addition, the recent introduction of highly efficient direct-acting antivirals (DAAs) led to viral eradication and a significant decrease in liver damage, lowering the risk of hepatic decompensation, and HCC. Therefore, CHC patients need proper noninvasive and repeatable methods for adequate surveillance, even after treatment, as there still remains a risk of portal hypertension and HCC. However, the usefulness for monitoring fibrosis after the sustained virological response (SVR) needs further research.

**Keywords:** chronic hepatitis C, fibrosis, Vibration Controlled Transient Elastography, point-shear wave elastography, 2D shear wave elastography

#### **1. Introduction**

Hepatitis C virus (HCV) infection is a major causative agent of chronic liver disease (CLD) and liver-related death worldwide. Approximately 4 out of 5 infected individuals develop chronic hepatitis C (CHC) and nearly 20% of them insidiously progress to cirrhosis, hepatocellular carcinoma (HCC), and end-stage liver disease [1]. It is estimated that 71.1 people were infected in 2015 worldwide, making it a global public health issue due to its substantial prevalence and effect on overall morbidity and mortality [2].

It has been shown that the accumulation of liver fibrosis has a great impact on the evolution of CHC. Fibrosis is the hallmark of progressive disease, eventually leading to cirrhosis and end-stage liver complications [3]. As highlighted by a prospective

study conducted by Yano et al. [4], relatively few patients with absent or low-grade fibrosis develop cirrhosis over the next 20 years (25–30%). However, portal and septal fibrosis were followed by cirrhosis in all cases with a progression rate of 18–20 years for portal fibrosis and 8–10 years for septal fibrosis. Furthermore, the advent of direct-acting antivirals (DAAs) has changed the perspective of CHC therapy, being both well-tolerated and highly efficient in achieving sustained virologic response (SVR) [5]. Therefore, staging liver fibrosis as a triage for starting therapy may no longer be as decisive as before. Rather, prompt diagnosis and management of advanced stages of fibrosis can prevent complications and death through comprehensive preventive and management strategies [6].

Liver biopsy (LB) is traditionally considered the gold standard evaluation for necroinflammatory activity, steatosis, and fibrosis in CHC [7]. However, the method has several drawbacks. Firstly, the result of the histopathological examination is significantly affected by the specimen's quality and the pathologist's experience [8–11]. Secondly, it is an invasive procedure, implies high costs, and might lead to several complications. Noninvasive methods are therefore necessary for optimal risk stratification in order to avoid the use of LB. Even if conventional imaging techniques are noninvasive, they require absolute signs of severe fibrosis or cirrhosis. Therefore, the latest studies focused on noninvasive elastographic techniques, which have shown promising results for the appraisal of liver fibrosis and steatosis in CHC patients.
