title: Contrast enhanced MR angiography with parallel imaging in the early period after renal transplantation.
abstract: OBJECTIVE
  To evaluate renal allograft vessels in the early period after kidney transplantation with three-dimensional (3D) contrast-enhanced MR angiography (3D CE MRA) using a parallel imaging technique.
  
  
  METHODS
  Sixty-three consecutive patients were examined with 3D CE MRA and integrated SENSE technique (Sensitivity Encoding) 2 to 21 days after renal transplantation. MR angiography studies were analyzed for the presence of arterial stenosis. The degree of renal transplant artery stenosis was graded qualitatively as <50% = mild, 50-70% = moderate, 70-99% = severe, and occlusion. Four patients (6.3%) with moderate (n = 1) or severe (n = 3) arterial stenoses on CE MRA underwent selective intra-arterial digital subtraction angiography. In two patients, selective intravenous digital subtraction angiography (DSA) was performed.
  
  
  RESULTS
  Twenty-seven (42.9%) of the 63 patients had normal CE MR angiograms, 29 (46%) showed mild, 3 patients (4.8%) moderate, and 4 patients (6.3%) severe stenoses of the donor artery. In three patients, the severe stenosis of the graft artery was confirmed by surgery or intra-arterial DSA. One patient with suspicion of severe arterial stenosis on MRA had moderate vessel narrowing on DSA. Twelve months after kidney transplantation, serum creatinine levels were not significantly different in patients with mild and moderate stenoses from those without (P > 0.19) but significantly different from those with severe stenoses (P < 0.05).
  
  
  CONCLUSIONS
  The incidence of mild and moderate vessel narrowing at the arterial anastomosis is unexpectedly high in the early period after kidney transplantation and is most likely due to surgery-related tissue edema.
authors.affiliation: Department of Diagnostic and Interventional Radiology, University Clinic of Rostock, Rostock, Germany.
authors.forename: Hubert
authors.initials: H
authors.lastname: Gufler
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Weimer
authors.forename: Kathleen
authors.initials: K
authors.lastname: Neu
authors.forename: Sabine
authors.initials: S
authors.lastname: Wagner
authors.forename: Wigbert Stephan
authors.initials: WS
authors.lastname: Rau
mesh_terms: D000328:Adult; D000368:Aged; D015901:Angiography, Digital Subtraction; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D021621:Imaging, Three-Dimensional; D007668:Kidney / Q000098:blood supply*; D016030:Kidney Transplantation; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000175:diagnosis* / Q000000981:diagnostic imaging; D012078:Renal Artery Obstruction / Q000175:diagnosis* / Q000000981:diagnostic imaging
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA