Liver stiffness in healthy subjects measured by shear wave elastography (SWE)

Abstract

Purpose To investigate liver stiffness (LS) in healthy subjects using shear wave elastography (SWE), and to determine the threshold value of LS for differentiating healthy subjects from patients with chronic liver diseases.

Materials and Methods 169 patients who underwent liver ultrasonography coupled with SWE were enrolled. They were assigned to one of three groups, based on clinical and pathological criteria: normal (n=102), non-cirrhotic chronic liver disease (NCCLD; n=53), and biopsy-proven NCCLD (n=14). LS was measured in the right liver, and the median value of 10 measurements was calculated. Both mean and median values in the normal group were compared with those in the NCCLD group. To determine the optimum threshold value for discriminating normal subjects from patients with chronic liver disease, a ROC curve analysis was performed.

Results The mean value of LS in the normal group was 5.41 kPa. In the NCCLD and biopsy-proven NCCLD groups, mean LS values were 8.13 and 9.93 kPa, respectively. Differences between the normal and both NCCLD groups were statistically significant (p<.001). The optimal threshold value of LS for discriminating normal liver from NCCLD was 6.86 kPa. Sensitivity using this threshold was 94%.

Conclusion The optimal threshold value for differentiating healthy subjects from patients with chronic liver disease is 6.86 kPa.