title: Comparison of Ultrasound Corticomedullary Strain with Doppler Parameters in Assessment of Renal Allograft Interstitial Fibrosis/Tubular Atrophy.
abstract: To compare the capability of ultrasound strain and Doppler parameters in the assessment of renal allograft interstitial fibrosis/tubular atrophy (IF/TA), we prospectively measured ultrasound corticomedullary strain (strain) and intra-renal artery Doppler end-diastolic velocity (EDV), peak systolic velocity (PSV) and resistive index (RI) in 45 renal transplant recipients before their kidney biopsies. We used 2-D speckle tracking to estimate strain, the deformation ratio of renal cortex to medulla produced by external compression using the ultrasound transducer. We also measured Doppler EDV, PSV and RI at the renal allograft inter-lobar artery. Using the Banff scoring system for renal allograft IF/TA, 45 patients were divided into the following groups: group 1 with ≤5% (n = 12) cortical IF/TA; group 2 with 6%-25% (n = 12); group 3 with 26%-50% (n = 11); and group 4 with >50% (n = 10). We performed receiver operating characteristic curve analysis to test the accuracy of these ultrasound parameters and duration of transplantation in determining >26% cortical IF/TA. In our results, strain was statistically significant in all paired groups (all p < 0.005) and inversely correlated with the grade of cortical IF/TA (p < 0.001). However, the difference in PSV and EDV was significant only between high-grade (>26%, including 26%-50% and >50%) and low-grade (≤25%, including <5% and 6%-25%) cortical IF/TA (p < 0.001). RI did not significantly differ in any paired group (all p > 0.05). The areas under the receiver operating characteristic curve for strain, EDV, PSV, RI and duration of transplantation in determining >26% cortical IF/TA were 0.99, 0.94, 0.88, 0.52 and 0.92, respectively. Our results suggest that corticomedullary strain seems to be superior to Doppler parameters and duration of transplantation in assessment of renal allograft cortical IF/TA.
authors.affiliation: Department of Radiology, Weill Cornell Medical College, New York, New York, USA. Electronic address: jig2001@med.cornell.edu.
authors.forename: Jing
authors.initials: J
authors.lastname: Gao
authors.affiliation: Department of Radiology, University of Michigan Hospitals, Ann Arbor, Michigan, USA.
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Rubin
authors.affiliation: University of Michigan Hospitals, VA Medical Center, Ann Arbor, Michigan, USA.
authors.forename: William
authors.initials: W
authors.lastname: Weitzel
authors.affiliation: Rogosin Institute, Weill Cornell Medical College, New York, New York, USA.
authors.forename: Jun
authors.initials: J
authors.lastname: Lee
authors.affiliation: Rogosin Institute, Weill Cornell Medical College, New York, New York, USA.
authors.forename: Darshana
authors.initials: D
authors.lastname: Dadhania
authors.affiliation: Department of Surgery, Weill Cornell Medical College, New York, New York, USA.
authors.forename: Sandip
authors.initials: S
authors.lastname: Kapur
authors.affiliation: Department of Radiology, Weill Cornell Medical College, New York, New York, USA.
authors.forename: Robert
authors.initials: R
authors.lastname: Min
mesh_terms: D000328:Adult; D000368:Aged; D055119:Elastic Modulus; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D005355:Fibrosis / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D007672:Kidney Cortex / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology; D007673:Kidney Cortex Necrosis / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology*; D007681:Kidney Papillary Necrosis; D016030:Kidney Transplantation / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013314:Stress, Mechanical
keywords: Doppler velocity; Renal cortical interstitial fibrosis/tubular atrophy; Renal transplant; Ultrasound strain