Application of Real-Time Sound Touch Elastography for Evaluating Chronic Kidney Disease of Transplanted Kidneys.

ABSTRACT

BACKGROUND: If chronic allograft nephropathy can be detected early and treated, the long-term survival rate of the transplanted kidney may be effectively improved. PURPOSE: To compare the application value of real-time sound touch elastography (STE), strain elastography, and color Doppler flow imaging in evaluating chronic kidney disease of transplanted kidneys. MATERIALS AND METHODS: A total of 101 patients with renal transplantation were divided into a normal group (serum creatinine <134 mol/L, 58 patients) and a chronic allograft nephropathy group after renal transplantation over 6 months (serum creatinine >134 mol/L, 43 patients). The maximum elastic modulus (Emax) was determined, and receiver operator characteristics were used to compare the diagnostic efficacy of STE ultrasound. RESULTS: Emean, Emax, B/A (the strain rate of the internal oblique muscle tissue/ the strain rate of the central renal cortex) of cortical standard strain ratio in strain elastography, and resistance index (RI) between normal and chronic allograft nephropathy groups have statistical significance (P < .05). Emax is superior to B/A and arcuate artery RI in the chronic cortex in the diagnosis of renal dysfunction, and the area under the receiver operator characteristics curve is 0.88. The estimated glomerular filtration rate was negatively correlated with renal cortex Emax, B/A, and arcuate artery RI, among which Emax was the strongest (r = - 0.713, P < .001). The renal cortical Emax cut-off was 30.95 kPa, the sensitivity was 92%, the specificity was 88%, and the accuracy was 88%. CONCLUSION: The STE technique to evaluate chronic renal dysfunction after renal transplantation is more sensitive than traditional strain-type elastography and hemodynamic parameters, with renal function decline, renal cortex Emax, renal cortical B/A, and arcuate artery RI gradually increased, and renal cortex Emax was particularly obvious.