title: Spinal dysraphism at MR urography: initial experience.
abstract: OBJECTIVE
  To prospectively evaluate the role of magnetic resonance (MR) urography in the radiologic assessment of patients with spinal dysraphism.
  
  
  METHODS
  Fourteen patients with spinal dysraphism were referred for MR urography with half-Fourier rapid acquisition with relaxation enhancement (RARE) (repetition time msec/echo time msec = 11.9/95) and RARE (2,800/1,100) sequences on a 1.5-T MR machine. Six patients did not tolerate MR urography owing to claustrophobia (n = 4) or flexion deformities (n = 2), giving a final success rate of 57% (eight patients). Two patients had a single kidney (one after nephrectomy, one with a crossed-fused ectopic kidney). Images were jointly assessed by two radiologists and compared with excretory urographic studies. The signal intensity ratio and contrast-to-noise ratio were also calculated.
  
  
  RESULTS
  Visualization of the kidneys, pelvicaliceal system, and ureters was better with half-Fourier RARE than with RARE imaging, whereas visualization of the bladder was comparable with both sequences. The mean signal intensity ratios for half-Fourier RARE and RARE sequences, respectively, were 16.2 +/- 3.65 and 19.2 +/- 3.65 (P =. 58, factorial analysis of variance model), whereas the mean contrast-to-noise ratios were 55.4 +/- 5.16 and 47.8 +/- 5.16 (P =. 34). Cortical scarring was depicted more clearly at MR urography than at excretory urography, whereas a renal calculus seen at excretory urography was not detected at MR urography.
  
  
  CONCLUSIONS
  MR urography was feasible in 57% of patients with spinal dysraphism and is a safe, accurate method of evaluating the upper urinary tract.
authors.affiliation: Department of Radiology, Mater Misericordiae Hospital, Eccles St, Dublin 7, Ireland.
authors.forename: M M
authors.initials: MM
authors.lastname: Maher
authors.forename: T A
authors.initials: TA
authors.lastname: Prasad
authors.forename: J M
authors.initials: JM
authors.lastname: Fitzpatrick
authors.forename: J
authors.initials: J
authors.lastname: Corr
authors.forename: D H
authors.initials: DH
authors.lastname: Williams
authors.forename: J T
authors.initials: JT
authors.lastname: Ennis
authors.forename: J G
authors.initials: JG
authors.lastname: Murray
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D007668:Kidney / Q000002:abnormalities; D008279:Magnetic Resonance Imaging; D008297:Male; D011446:Prospective Studies; D016135:Spinal Dysraphism / Q000150:complications* / Q000473:pathology; D014551:Urinary Tract / Q000473:pathology*; D014570:Urologic Diseases / Q000150:complications / Q000175:diagnosis*