title: Ultrasound strain elastography in assessment of cortical mechanical behavior in acute renal vein occlusion: in vivo animal model.
abstract: To assess the correlation of quantitative ultrasound strain parameters with the severity of cortical edema in renal vein occlusion, we prospectively performed ultrasound strain elastography on a canine acute renal vein occlusion model prior to and following 10, 20, and 40min of renal vein ligation. Strain and strain relaxation time representing the deformation and relaxation of the renal cortices and reference soft tissue were produced by the external compression with the ultrasound transducer and estimated using commercially available 2-D speckle tracking software. Cortical thickness was additionally measured. Repeated-measures analysis of variance was used to examine the difference in cortical thickness, strain ratio (mean cortical strain divided by mean reference tissue strain), and strain relaxation time ratio (cortical relaxation time divided by reference tissue relaxation time) prior to and after renal vein ligation. Pearson's correlation coefficient was applied to test the relationship between strain parameters and the time of the renal vein ligation. There was a strong positive correlation between the duration of renal vein ligation and strain (R(2)=0.97) and strain relaxation time (R(2)=0.98) ratios. Significant differences in strain and strain relaxation time ratios were found at all measured timepoints (all P≪.001). Cortical thickness, however, showed no significant difference between timepoints (P=.065). Our result suggest that strain and strain relaxation time ratios may be used as quantitative markers for the assessment of the renal cortical mechanical behavior in subclinical acute renal vein occlusion.
authors.affiliation: Department of Radiology, Weill Cornell Medical College, New York, NY, USA.
authors.forename: Jing
authors.initials: J
authors.lastname: Gao
authors.affiliation: Department of Ultrasound, Beijing Tiantan Hospital, Capital Medical University, Beijing, China. Electronic address: 168hewen@sina.com.
authors.forename: Wen
authors.initials: W
authors.lastname: He
authors.affiliation: Department of Ultrasound, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors.forename: Ling-Gang
authors.initials: LG
authors.lastname: Cheng
authors.affiliation: Department of Ultrasound, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors.forename: Xiao-Ya
authors.initials: XY
authors.lastname: Li
authors.affiliation: Department of Pathology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors.forename: Xiou-Ru
authors.initials: XR
authors.lastname: Zhang
authors.affiliation: Department of Radiology, Weill Cornell Medical College, New York, NY, USA.
authors.forename: Krishna
authors.initials: K
authors.lastname: Juluru
authors.affiliation: Department of Radiology, Weill Cornell Medical College, New York, NY, USA.
authors.forename: Noor
authors.initials: N
authors.lastname: Al Khori
authors.affiliation: Department of Radiology, Weill Cornell Medical College, New York, NY, USA.
authors.forename: Adrienne
authors.initials: A
authors.lastname: Coya
authors.affiliation: Department of Radiology, Weill Cornell Medical College, New York, NY, USA.
authors.forename: Robert
authors.initials: R
authors.lastname: Min
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D004285:Dogs; D054459:Elasticity Imaging Techniques / Q000379:methods*; D016030:Kidney Transplantation; D008297:Male; D012082:Renal Veins / Q000000981:diagnostic imaging*; D020246:Venous Thrombosis / Q000000981:diagnostic imaging*
keywords: Cortical mechanical behavior; Kidney biopsy; Poroelasticity; Renal vein occlusion; Ultrasound elasticity imaging