title: Early ultrasound assessment of renal transplantation as the valuable biomarker of long lasting graft survival: a cross-sectional study.
abstract: BACKGROUND
  To date, there has been little agreement on the use of ultrasonographic parameters in predicting the long-term outcome after transplantation. This study evaluates whether ultrasonography of the graft performed in the early stage after transplantation is a valuable predictor for long-term-outcome.
  
  
  OBJECTIVE
  The aim of this study was to evaluate the association of ultrasonographic parameters (resistive index [RI], pulsatility index[PI], end diastolic velocity [EDV], graft length and graft parenchymal volume) measured within the first week after transplantation with 6 months graft function.
  
  
  METHODS
  A cross-sectional study was performed on 91 (46 males and 45 females) living renal transplants between April 2011 and February 2013. All patients underwent an ultrasonography at the first week after transplantation. Intrarenal Doppler indices including RI, PI and EDV were measured at the interlobar artery level and the graft length and parenchymal volume were defined with gray scale ultrasonography. Graft function was estimated at 6months by glomerular filtration rate (GFR). Unpaired t-test and multivariate-linear and logistic regression analysis were used to estimate the relationship between ultrasonographic parameters and GFR.
  
  
  RESULTS
  Fourteen patients (15.4%) had impaired graft function after 6 months (GFR less than 60 ml/min/1.73m2). Multivariate linear regression analysis showed significant correlation between GFR at 6 months and RI, PI and EDV with a P value of 0.026, 0.016 and 0.015, respectively. Logistic regression analysis showed that GFR<60 ml/min/1.73 m2 at 6 months was significantly associated with RI>0.7 (odds ratio=2.20, P value=0.004) and PI>1.3 (odds ratio=2.74, P value<0.001) and EDV<9 cm/Sec (odds ratio=1.83, P value=0.03).
  
  
  CONCLUSIONS
  In this study, kidney transplant recipients with a lower RI and PI and a higher EDV at 1week showed better graft function at 6 months after transplantation.
authors.affiliation: Department of Radiology, Faculty of Medicine and Health Sciences, Kerman University of Medical Sciences, Kerman, Iran.
authors.forename: Ahmad
authors.initials: A
authors.lastname: Enhesari
authors.affiliation: Department of Radiology, Faculty of Medicine and Health Sciences, Kerman University of Medical Sciences, Kerman, Iran.
authors.forename: Saeid
authors.initials: S
authors.lastname: Mardpour
authors.affiliation: Department of Radiology, Faculty of Medicine and Health Sciences, Kerman University of Medical Sciences, Kerman, Iran.
authors.forename: Zohreh
authors.initials: Z
authors.lastname: Makki
authors.affiliation: Applied Cell Sciences Department, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Soura
authors.initials: S
authors.lastname: Mardpour
keywords: Glomerular Filtration Rate; Kidney Transplantation; Ultrasonography