title: Evaluation of dynamic gadolinium-enhanced breath-hold MR angiography in the diagnosis of renal artery stenosis.
abstract: OBJECTIVE
  The aim of our study was to evaluate a three-dimensional gadolinium-enhanced breath-hold MR angiography sequence using standard MR gradients in detecting renal artery stenosis.
  
  
  METHODS
  Forty-two patients referred for angiography for suspected renal artery stenosis underwent both conventional digital subtraction angiography (DSA) and MR angiography. MR angiography was performed on a 1.5-T scanner with standard gradients. A fast multiplanar spoiled gradient-echo sequence was used with the following parameters: TR/TE, 10.3/1.9; flip angle, 45 degrees; field of view, 36 x 32 cm; matrix size, 256 x 128; one excitation; volume thickness, 70 mm; and partitions, 28. Gadolinium was administered IV as a dynamic bolus of 30-40 ml. Conventional and MR angiographic images were interpreted by two radiologists in consensus.
  
  
  RESULTS
  DSA revealed 87 renal arteries, of which 79 were in 35 patients with native kidneys and eight arteries were in seven patients with transplanted kidneys. Gadolinium-enhanced MR angiography showed 85 (98%) of 87 renal arteries. Seventeen patients had 20 significant (>50% stenosis) renal artery stenoses and five patients had five occluded renal arteries revealed by DSA. MR angiography revealed 85 renal arteries (98%), 20 stenoses (100%), and five occlusions (100%). Gadolinium-enhanced MR angiography led to one false-positive interpretation for renal artery stenosis and no false-negative interpretations. Thus, the sensitivity, specificity, and accuracy of MR angiography for renal artery stenosis were 100%, 98%, and 99%, respectively.
  
  
  CONCLUSIONS
  The MR angiography pulse sequence we used was an effective and reliable technique for the diagnosis of renal artery stenosis. The sequence can be performed on widely available MR equipment that does not require fast gradient hardware.
authors.affiliation: Department of Radiology, Beaumont Hospital and Royal College of Surgeons in Ireland, Dublin.
authors.forename: M J
authors.initials: MJ
authors.lastname: Thornton
authors.forename: F
authors.initials: F
authors.lastname: Thornton
authors.forename: J
authors.initials: J
authors.lastname: O'Callaghan
authors.forename: J C
authors.initials: JC
authors.lastname: Varghese
authors.forename: E
authors.initials: E
authors.lastname: O'Brien
authors.forename: J
authors.initials: J
authors.lastname: Walshe
authors.forename: M J
authors.initials: MJ
authors.lastname: Lee
mesh_terms: D000328:Adult; D000368:Aged; D015901:Angiography, Digital Subtraction; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007089:Image Enhancement; D007091:Image Processing, Computer-Assisted; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012078:Renal Artery Obstruction / Q000175:diagnosis*
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA