Preliminary study on the kidney elasticity quantification in patients with chronic kidney disease using virtual touch tissue quantification

Abstract

Background: Virtual touch tissue quantification (VTTQ) provides numerical measurements (shear wave velocity (SWV) values) of tissue stiffness. Objectives: The purpose of this study was to describe the SWV values of the kidney by VTTQ and to examine the clinical usefulness of this procedure in the evaluation of elasticity changes in the kidneys of patients with chronic kidney disease (CKD). Patients and Methods: Sixty-five patients with CKD and seventy healthy participants were included in this study. A total of 270 kidneys were examined by VTTQ. The kidney elasticity was expressed as shear wave velocity. The SWV values, blood serum creatinine (Scr)/BUN and pathological findings were analyzed and compared between patients with CKD and healthy participants. Results: In patients with CKD and healthy participants, the SWV values both gradually decreased from the renal cortex to the medulla and renal sinus The SWV value of the renal cortex in patients with CKD was less than that of healthy participants (P < 0.05), and the SWV value of the renal cortex in patients with renal insufficiency was significantly less than in those with normal renal function (2.46 ± 0.15 vs. 3.45 ± 0.26 m/s, P < 0.05). The best cutoff value for predicting renal insufficiency (Scr > 1.24 mg/dL or/and BUN > 21 mg/DL) was a SWV value of the renal cortex of less than 1.92 m/s with a sensitivity of 84.4% (95% CI: 67.2-94.7%) and a specificity of 96.8% (95% CI: 83.3-99.9%) (P < 0.001). Conclusion: VTTQ can sensitively detect the elasticity changes in patients with CKD, and it can effectively predict renal insufficiency. This technology provides a valuable tool for the assessment of CKD.