PERIANAL FISTULA

MRI is increasingly used nowadays in the evaluation and management of PerianalFistula. Objectives: To assess the role of MRI in the detection and classification of PerianalFistula and correlation of preoperative MRI findings with the findings on surgery. Study Design:Prospective study. Setting: Department of Radiology King Khalid Civilian Hospital TabukKingdom of Saudi Arabia. Study Period: Two years between February 2013 and February 2015.Material and Methods: 60 patients were referred from surgical department for evaluation ofPerianal fistula by MRI during the above mentioned period. MRI was performed in 48 Patients.(42 males and 6 Females) using variety of MRI sequences. Fistulas were classified according toSJUH (St James’s University Hospital classification MR imaging based grading system) and MRIfindings of individual MRI sequence used were correlated with operative findings. Results: Mostcommon fistula was Grade 1 (37.5%).In majority of the cases internal opening was found at 6 Oclock position. Post intravenous contrast enhanced Axial and coronal oblique (CE FST1WFSE)Fat suppressed T1 weighted Fast spin echo and Axial and coronal Fat suppressed T2W FSEsequence (FST2WFSE) showed the highest Accuracies 98.13% and 97.06% respectively indiagnosis of anorectal fistulae. Conclusion: MRI should be used as a first line imaging modalityin the preoperative assessment of Perianal fistula. Findings on Axial and coronal oblique CEFST1WFSE, axial and coronal oblique FST2WFSE showed the excellent agreement with thesurgical findings. By using MRI as the first line imaging modality in the evaluation of PerianalFistula one can percept best possible surgical management resulting in prevention of residual/recurrence disease and complications such as fecal incontinence.