title: Multidetector row CT angiography of living related renal donors: is there a need for venous phase imaging?
abstract: OBJECTIVE
  To prospectively evaluate whether renal venous anatomy can be detected from arterial phase images of multidetector row CT (MDCT) of renal donors.
  
  
  METHODS
  Institutional review board approved our study protocol with waiver of consent. Forty-eight consecutive renal donors (age range, 21-56 years; M:F, 20:28) referred for MDCT evaluation were included. Two sub-specialty radiologists performed an independent and separate evaluation of renal venous anatomy in arterial and venous phase images. Opacification of renal venous structures was scored on a five-point scale (1-not seen; 3-minimal opacification; 5-excellent opacification). Arterial and venous phase opacification scores were compared by Wilcoxon signed rank test.
  
  
  RESULTS
  Both readers detected all renal venous anomalies in arterial as well as venous phase images. Each reader detected accessory right renal veins (n=14), retroaortic left renal vein (n=2), circumaortic left renal vein (n=1), and left renal hilar arteriovenous malformation (n=1) in arterial phase images. Retroaortic left renal venous branch was difficult to differentiate from lumbar vein (reader-1, n=1; reader-2, n=2) in both arterial and venous phase images. Sensitivity of detection of renal veins, left adrenal, gonadal and lumbar veins in arterial phase images was 100, 83-88, 100, and 85-90%, respectively. As expected, venous phase images showed significantly greater opacification of renal veins, left gonadal, adrenal and lumbar veins (p<.05). However, this did not substantially limit the evaluation of renal venous anatomy in arterial phase images. Both readers had substantial interobserver agreement (kappa coefficient, 0.7; p<0.05).
  
  
  CONCLUSIONS
  Arterial phase MDCT images alone can be used to detect renal venous anomalies, and to identify small left renal venous branches namely, the left gonadal, adrenal and lumbar veins in renal donors. Venous phase MDCT acquisition is not necessary for evaluation of renal venous anatomy in renal donors.
authors.affiliation: Department of Radiology, Division of Abdominal Imaging, Emory University School of Medicine, 1364 Clifton Road NE, Atlanta, GA 30322, United States.
authors.forename: Saravanan
authors.initials: S
authors.lastname: Namasivayam
authors.forename: Mannudeep K
authors.initials: MK
authors.lastname: Kalra
authors.forename: Sandra M
authors.initials: SM
authors.lastname: Waldrop
authors.forename: Pardeep K
authors.initials: PK
authors.lastname: Mittal
authors.forename: William C
authors.initials: WC
authors.lastname: Small
mesh_terms: D000328:Adult; D000792:Angiography / Q000379:methods*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007668:Kidney / Q000098:blood supply* / Q000000981:diagnostic imaging*; D016030:Kidney Transplantation; D019520:Living Donors; D008297:Male; D008875:Middle Aged; D012082:Renal Veins / Q000000981:diagnostic imaging*; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric; D014057:Tomography, X-Ray Computed