title: Magnetic resonance imaging with rectal Gd-DTPA: new tool for the diagnosis of perianal fistula.
abstract: This study investigated the effectiveness of magnetic resonance imaging (MRI) with rectal administration of the enteral contrast agent gadolinium diethylene triamine pentaacetic acid (Gd-DTPA) in the diagnosis of recurrent perianal fistulae, assessing the number, anatomical extent, location, and signal intensities of various lesions. Fistulas were examined by MRI before and after rectal administration of Gd-DTPA in 50 patients (excluding fistulas due to inflammatory bowel disease). Surgical findings were compared with both pre- and postcontrast T1-weighted, T2-weighted, and short T1 inversion recovery (STIR) sequences. Of the 68 fistulous tracts detected surgically, precontrast imaging identified 16 by T1-weighted images (hypointense), 27 by T2-weighted images (hyperintense or iso- to weakly hyperintense), and 54 by STIR. Postcontrast imaging identified 29 by T1-weighted images, 58 by T2-weighted, and 54 by STIR. MRI with rectal administration of Gd-DTPA thus facilitates determination of fistula tracts, which are better resolved by precontrast STIR than by either precontrast T1- or T2-weighted images. Postcontrast T2-weighted images were substantially superior to T1-weighted. Both noncontrast STIR and postcontrast T2-weighted sequences were adequate for classifying fistulas in ano, but in complex recurrent anal fistula postcontrast T2-weighted images were more helpful.
authors.affiliation: Department of Radiology, Pamukkale University School of Medicine, Denizli, Turkey.
authors.forename: N
authors.initials: N
authors.lastname: Sabir
authors.forename: U
authors.initials: U
authors.lastname: Sungurtekin
authors.forename: E
authors.initials: E
authors.lastname: Erdem
authors.forename: M
authors.initials: M
authors.lastname: Nessar
mesh_terms: D000328:Adult; D003287:Contrast Media / Q000494:pharmacology; D005260:Female; D019786:Gadolinium DTPA / Q000494:pharmacology; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012003:Rectal Fistula / Q000175:diagnosis* / Q000473:pathology* / Q000601:surgery; D012007:Rectum / Q000473:pathology* / Q000502:physiology*
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA