PURPOSE: To assess the value of MRI performed with phased-array coil in the diagnosis and preoperative staging of perianal and anal fistulas. MATERIALS AND METHODS: 20 patients (13 with Crohn's disease) with clinical evidence or suspicion of anal fistulas underwent pelvic MRI (1.5 T) performed with phased-array coil. Images were obtained in the axial and coronal planes using TSE T2-weighted high resolution sequences with and without fat suppression, T2-weighted HASTE and T1-weighted FLASH sequences, with and without fat suppression, before and after gadolinium enhancement. The following parameters were considered: presence of a fistula and relation with the sphincters, and presence of abscesses or complications. All patients underwent surgery. The MRI and surgical findings were assessed using the Park's fistula-in-ano classification and the St. James MR imaging classification of perianal fistulas. Surgery was considered the gold standard. RESULTS: MRI documented no evidence of fistula in 2 patients, intersphinteric fistulas in 5 (grade 1 and 2 St. James), trans-sphincteric fistulas in 9 (grade 3 and 4 St. James), translevator in 2 (grade 5) and complex ano-rectum-vaginal fistulas in 2. Concordance with surgery was 90%. CONCLUSIONS: MRI is an accurate technique for the identification and classification of anal and perianal fistulas and their complications. In our experience the phased-array coil offers both high field of view and spatial resolution, enabling the demonstration of perianal pathology.
PURPOSE: To assess the value of MRI performed with phased-array coil in the diagnosis and preoperative staging of perianal and anal fistulas. MATERIALS AND METHODS: 20 patients (13 with Crohn's disease) with clinical evidence or suspicion of anal fistulas underwent pelvic MRI (1.5 T) performed with phased-array coil. Images were obtained in the axial and coronal planes using TSE T2-weighted high resolution sequences with and without fat suppression, T2-weighted HASTE and T1-weighted FLASH sequences, with and without fat suppression, before and after gadolinium enhancement. The following parameters were considered: presence of a fistula and relation with the sphincters, and presence of abscesses or complications. All patients underwent surgery. The MRI and surgical findings were assessed using the Park's fistula-in-ano classification and the St. James MR imaging classification of perianal fistulas. Surgery was considered the gold standard. RESULTS: MRI documented no evidence of fistula in 2 patients, intersphinteric fistulas in 5 (grade 1 and 2 St. James), trans-sphincteric fistulas in 9 (grade 3 and 4 St. James), translevator in 2 (grade 5) and complex ano-rectum-vaginal fistulas in 2. Concordance with surgery was 90%. CONCLUSIONS: MRI is an accurate technique for the identification and classification of anal and perianal fistulas and their complications. In our experience the phased-array coil offers both high field of view and spatial resolution, enabling the demonstration of perianal pathology.
Authors: D Bouchard; L Abramowitz; G Bouguen; C Brochard; A Dabadie; V de Parades; M Eléouet-Kaplan; N Fathallah; J-L Faucheron; L Maggiori; Y Panis; F Pigot; P Rouméguère; A Sénéjoux; L Siproudhis; G Staumont; J-M Suduca; B Vinson-Bonnet; J-D Zeitoun Journal: Tech Coloproctol Date: 2017-09-19 Impact factor: 3.781