title: Tissue elasticity quantification by acoustic radiation force impulse for the assessment of renal allograft function.
abstract: Acoustic radiation force impulse (ARFI) quantification, a novel ultrasound-based elastography method, has been used to measure liver fibrosis. However, few studies have been performed on the use of ARFI quantification in kidney examinations. We evaluated renal allograft stiffness using ARFI quantification in patients with stable renal function (n = 52) and those with biopsy-proven allograft dysfunction (n = 50). ARFI quantification, given as shear wave velocity (SWV), was performed. The resistance index (RI) was calculated by pulsed-wave Doppler ultrasound, and clinical and laboratory data were collected. Morphologic changes in transplanted kidneys were diagnosed by an independent pathologist. Mean SWV was more significantly negatively correlated with estimated glomerular filtration rate (eGFR) (r = -0.657, p < 0.0001) than was RI (r = -0.429, p = 0.0004) in transplanted kidneys. Receiver operating characteristic curve analysis revealed that the sensitivity and specificity of quantitative ultrasound in the diagnosis of renal allograft dysfunction were 72.0% and 86.5% (cutoff value = 2.625), respectively. The latter values were better than those of RI, which were 62.0% and 69.2% (cutoff value = 0.625), respectively. The coefficient of variation for repeat SWV measurements of the middle part of transplanted kidney was 8.64%, and inter-observer agreement on SWV was good (Bland-Altman method, ICC = 0.890). In conclusion, tissue elasticity quantification by ARFI is more accurate than the RI in diagnosing renal allograft function.
authors: Department of Ultrasound, Zhongshan Hospital, Fudan University, Shanghai, China; Shanghai Institute of Imaging Medicine, Shanghai, China.
authors: Wan-Yuan
authors: WY
authors: He
authors: Department of Ultrasound, Zhongshan Hospital, Fudan University, Shanghai, China; Shanghai Institute of Imaging Medicine, Shanghai, China.
authors: Yun-Jie
authors: YJ
authors: Jin
authors: Department of Ultrasound, Zhongshan Hospital, Fudan University, Shanghai, China. Electronic address: puguang61@126.com.
authors: Wen-Ping
authors: WP
authors: Wang
authors: Department of Ultrasound, Zhongshan Hospital, Fudan University, Shanghai, China.
authors: Chao-Lun
authors: CL
authors: Li
authors: Department of Ultrasound, Zhongshan Hospital, Fudan University, Shanghai, China.
authors: Zheng-Biao
authors: ZB
authors: Ji
authors: Department of Urology, Zhongshan Hospital, Fudan University, Shanghai, China; Shanghai Key Laboratory of Organ Transplantation, Shanghai, China.
authors: Cheng
authors: C
authors: Yang
mesh_terms: D000293:Adolescent; D000328:Adult; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D006084:Graft Rejection / Q000000981:diagnostic imaging* / Q000209:etiology*; D006085:Graft Survival; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D007668:Kidney / Q000000981:diagnostic imaging* / Q000601:surgery*; D007677:Kidney Function Tests / Q000379:methods*; D016030:Kidney Transplantation / Q000009:adverse effects*; D008297:Male; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016896:Treatment Outcome; D055815:Young Adult
keywords: Acoustic radiation force impulse; Elastography; Non-invasive diagnosis; Renal transplantation