Rajendra N. Solanki1, Hetali A. Rathod2, Deepali Shah3, Pankaj Amin4
We presented role of MRI in fistula-in-ano before the surgery. In our institute, we do preoperative MRI in all the patients presented with perianal discharge or external opening. MRI is very accurate for depiction of both the primary tract (sensitivity, 100%; specificity, 86%) and abscesses (sensitivity, 96%; specificity, 97%).
The aim of the study is to classify the perianal fistulas according to the St. James University Hospital (SJUH) grading scheme and Park’s classification and to evaluate the different characteristics of the fistula-in-ano in clinically-diagnosed cases.
MATERIALS AND METHODS
1.5 Tesla MRI machine was used to scan the patients. 30 patients were taken from July 2013 to December 2015. All the patients underwent MRI study on the basis of inclusion and exclusion criteria. Following sequences used as imaging protocols, T2 TSE FS- COR/TRA/SAG, T2 TSE- COR/TRA, T1 TSE- COR/TRA/SAG, T1 TSE FS- COR/TRA/STIR and T1 TSE FS (PC)- COR/TRA. MR contrast was used as and when indicated to confirm the nature of disease.
In our study group, most of the cases (56%) were seen in patients of age group 41-50 years with predominant male population. In our study of 30 patients (36%) showed presence of associated ischiorectal or ischioanal abscesses on MRI. About 26% cases had intersphincteric collection/abscess. Horseshoe-shaped extension was found in 1 patient (3%). 16% patients showed presence of secondary tracts. Complex fistula with multiple tracts and openings was seen in 12 (40%) patients. Most of the patients (93%) in our study had low fistulae, other 6.6% patients showed a high fistula, which is important for the surgeons to know in order to avoid incontinence.
MR- Anal fistulogram is recommended in newly-diagnosed case as well as in recurrent and complex cases of fistula-in-ano as a method of preoperative evaluation to predict and hence reduce postoperative recurrences.