**5. Liver fibrosis assessment through point-shear wave elastography in HCV patients**

Point-shear wave elastography (p-SWE) is incorporated into devices such as Virtual Touch Tissue Quantification (VTTQ®) (Siemens Healthcare, Erlangen, Germany) and Elastography Point Quantification (ElastPQ®) (EPIQ7 ultrasound system, Philips Healthcare, Bothell, WE, USA). Under B-mode visualization, p-SWE enables the precise acquisition of shear wave speed (SWS) in a small ROI (around 1 cm3 ). After 10 valid measurements in the right hepatic lobe, the median of SWS is reported and interpreted [15, 52]. Results are expressed in m/s for VTTQ or in m/s and kPa for ElastPQ [13]. However, its narrow range (0.5–4.4 m/s) restricts the


*Noninvasive Assessment of HCV Patients Using Ultrasound Elastography DOI: http://dx.doi.org/10.5772/intechopen.102294*

> **Table 2.**

*2vXL probe.*

*Performance of VCTE for detecting different stages of fibrosis in HCV-infected patients.*


*Elastography - Applications in Clinical Medicine*



*Performance of p-SWE for detecting different stages of fibrosis in HCV-infected patients.*

*3VCTE as reference method.*

**Table 3.**

demarcation of proper cutoff values for discriminating between certain fibrosis stages, making management decisions difficult [14].

We identified several studies that evaluate p-SWE in HCV-infected patients [53–76]. A 2011 pooled meta-analysis by Friedrich-Rust et al. [58] with 380 CHC patients, found AUROC values of 0.88, 0.90, and 0.92 for diagnosing moderate fibrosis (≥ F2), severe fibrosis (≥ F3), and cirrhosis (= F4), respectively. Subsequently, an international multicenter study with 911 HCV-infected patients offered cut-off values of 1.19, 1.33, 1.43, respectively 1.55 m/s for ≥ F1, ≥ F2, ≥ F3 respectively F4, with AUROC values of 0.779, 0.792, 0.829 and 0.842, respectively [59]. Off note is the Takaki study [65] which elaborated the VIA index, a formula that increases the diagnostic accuracy of SWV alone, from 0.882, 0.858 and 1.000 to 0.917, 0.906, and 1.000 for moderate fibrosis, severe fibrosis, and cirrhosis, respectively in the validation set. In 2019, Hsu et al. [74] propound different SWV cutoff values in various diseases. For CHC patients, a SWV cut-off value of 1.225, 1.370 and 1.710 m/s predicts fibrosis stages ≥ F2, ≥ F3 and F4 with AUROC values of 0.786, 0.857 and 0.937, respectively. Overall, in our considered studies presented in **Table 3**, the AUROC ranged from 0.725 to 0.88 for ≥F1, 0.67 to 0.93 for ≥F2, 0.74 to 0.97 for ≥F3 and 0.79 to 1 for F4 prediction. Nonetheless, the EFSUMB Clinical Practice Guidelines suggest that pSWE can be the first-line assessment in HCV-infected patients for fibrosis evaluation, performing best at ruling out cirrhosis [15].
