title: Serial resistive index and pulsatility index for diagnosing renal complications in the early posttransplant phase: improving diagnostic efficacy by considering maximum values.
abstract: OBJECTIVE
  To present new approaches to using duplex Doppler scanning to detect kidney complications in the early posttransplant period.
  
  
  METHODS
  We assessed the resistive index and the pulsatility index in 127 renal transplant patients (73 men, mean age, 35.2 +/- 14 years) who underwent duplex Doppler scanning on the first, third, and fifth days after transplant. Biopsies were performed in patients suspected of having graft dysfunction owing to clinical and laboratory findings. To differentiate complicated from healthy grafts, a receiver operating characteristic curve analysis was done, and an area under the curve was calculated for each variable.
  
  
  RESULTS
  In total, 47 grafts (37%) became complicated (40 rejections). The mean resistive index and mean pulsatility indexwere statistically significantly higher on the first, third, and fifth days after transplant in patients with complicated grafts than they were in patients with noncomplicated grafts (P < .0001). The mean resistive index and mean pulsatility index showed a significant rise from the first to the fifth day in patients with complicated grafts (P = .014). The area under the curve of the receiver operating characteristic curve for resistive index and pulsatility index on successive days was statistically significant (P < .0001). The resistive index and the pulsatility index area under the curve were statistically significantly lower on the first day than they were on subsequent days. Considering the maximum value of a serially measured resistive index and pulsatility index (which were determined by comparing 3 measurements on the fifth day and selecting the highest one) as a new variable showed a better area under the curve compared with that calculated on the third day (P = .05 for resistive index; P = .012 for pulsatility index).
  
  
  CONCLUSIONS
  The resistive index and the pulsatility index are effective means of diagnosing posttransplant renal complications. Including a serial assessment and considering the maximum values could improve the diagnostic efficacy on the fifth day after transplant.
authors.affiliation: Department of Radiology, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran. apejmanht@yahoo.com
authors.forename: Ali
authors.initials: A
authors.lastname: Radmehr
authors.forename: Ali Babaei
authors.initials: AB
authors.lastname: Jandaghi
authors.forename: Amir Pejman
authors.initials: AP
authors.lastname: Hashemi Taheri
authors.forename: Madjid
authors.initials: M
authors.lastname: Shakiba
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D019540:Area Under Curve; D001706:Biopsy; D002648:Child; D002675:Child, Preschool; D003955:Diagnostic Tests, Routine; D005260:Female; D006084:Graft Rejection / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology*; D006801:Humans; D007668:Kidney / Q000000981:diagnostic imaging / Q000473:pathology / Q000502:physiology; D007674:Kidney Diseases / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology*; D016030:Kidney Transplantation / Q000000981:diagnostic imaging* / Q000473:pathology / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D012372:ROC Curve; D018616:Ultrasonography, Doppler, Duplex