title: Perianal fistulas: use of MR imaging for diagnosis.
abstract: OBJECTIVE
  To evaluate use of magnetic resonance (MR) imaging with saline solution as contrast agent in diagnosis of perianal fistulous disease.
  
  
  METHODS
  Spin-echo intermediate-, T2-, and T1-weighted images were obtained before and after instillation of saline solution into anal fistulas in 12 of 16 consecutive patients. In four patients without secretory fistulas, images were obtained without contrast enhancement.
  
  
  RESULTS
  Fistulous tracts were found in 13 patients, fluid cavities in 13, secondary fibrotic tracts in two, and normal perirectal tissue in one. The extent of fistulas and fluid collections was better delineated or more conspicuous on contrast-enhanced images in eight and 10 examinations, respectively, in part due to expansion of collapsed portions of the fistulous system. T2-weighted images were sufficient for diagnosis.
  
  
  CONCLUSIONS
  MR imaging with saline solution as contrast agent may improve visualization of fistulas and their relationship to normal anatomic structures in patients with complex fistulous systems with relatively sparse secretion.
authors.affiliation: MR Center, Medical Section, University Hospital, Trondheim, Norway.
authors.forename: G E
authors.initials: GE
authors.lastname: Myhr
authors.forename: H E
authors.initials: HE
authors.lastname: Myrvold
authors.forename: G
authors.initials: G
authors.lastname: Nilsen
authors.forename: J E
authors.initials: JE
authors.lastname: Thoresen
authors.forename: P A
authors.initials: PA
authors.lastname: Rinck
mesh_terms: D000328:Adult; D000368:Aged; D001003:Anal Canal / Q000473:pathology*; D003287:Contrast Media; D017577:Cutaneous Fistula / Q000175:diagnosis*; D005260:Female; D006801:Humans; D007412:Intestinal Fistula / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D012003:Rectal Fistula / Q000175:diagnosis*; D012007:Rectum / Q000473:pathology; D012965:Sodium Chloride
chemical_list: D003287:Contrast Media; D012965:Sodium Chloride