Aims: To prospectively assess the cutoff values of a point shear wave measurement (SWM) method for ruling-in and ruling-out significant fibrosis and cirrhosis using transient elastography (TE) as the reference standard.
Method: Consecutive patients with chronic hepatitis C were enrolled. Liver stiffness was assessed with the SWM method implemented on the HI VISION Ascendus ultrasound system (Hitachi Ltd, Japan) and with the TE method of the FibroScan® device (Echosens, France). For staging significant fibrosis (F>/=2) and cirrhosis (F=4) we used the TE cutoffs of 7.0 and 12.0 kiloPascal (kPa), respectively. The diagnostic performance of SWM was assessed by calculating the area under the receiver operating characteristic (AUROC) curve. Cutoffs with specificity or sensitivity > 90% were chosen to rule-in or rule-out F>/=2 and F=4.
Results: 445 individuals [235 males, 210 females; mean age, 61.1 (13.3) years] were studied: 190 (42.7%) individuals had F0-F1 fibrosis stage, 82 (18.4%) F2, 46 (10.3%) F3, and 127 (28.6%) F4 fibrosis stage. For ruling-in F>/=2 the SWM cutoff was 6.78 kPa [sensitivity, 76.9%(70.6-82.4); specificity, 90.3% (85.0-94.3)] and for ruling-out it was 5.55 kPa [sensitivity, 90.6% (85.8-94.1); specificity, 72.2% (64.9-78.6)]. For ruling-in F=4 the SWM cutoff was 9.15 kPa [sensitivity, 83.3% (74.4-90.2); specificity, 90.1% (86.0-93.2)] and for ruling-out it was 8.41 kPa [sensitivity, 90.6% (82.9-95.6); specificity, 82.2% (77.3-86.4)]. AUROCs were 0.92 (0.89-0.94) for F>/=2 and 0.94 (0.91-0.96) for F=4.
Conclusions: In clinical practice, the use of a dual cutoff of SWM may increase the confidence in staging liver fibrosis with a non-invasive shear wave elastography technique.