Role of Mri in the Diagnosis and Preoperative Classification of Perianal and Anal Fistulas

Abstract

Introduction: A fistula is described as an irregular connection between two surfaces that are coated in epithelium. Anal and perianal fistulas are aberrant connections between the anal canal and the skin's epithelium-lined surface. They are typically accompanied by one or more external openings in the perianal skin. It typically has an inflammatory component.

Aims: to assess the importance of MRI in the diagnosis and pre-operative staging of perianal and anal fistulas

Materials and method: In the radiology department of the Jorhat Medical College, a prospective comparative study was carried out on patients who were clinically diagnosed or suspected to have anal or perianal fistulas in both sexes and patients of all ages. The research timeframe was from JUNE 2021 to MAY 2022. This study had 47 patients in total.

Result: In our analysis, the majority of patients [38 (80.9%)] had a single internal opening. However, it was also discovered that there were several internal openings [4 (8.5%)] and internal openings in the rectum [2 (4.3%)] that were statistically significant (p<.00001) (z=7.51). We found that, lower number of patients had secondary tracts (MRI Findings) [12 (25.5%)] and it was statistically significant (p< .00001) (z=4.7445). Our investigation revealed that, statistically significantly (p.00001), the majority of patients had no abscess (MRI Findings) [36 (76.6%)] and no supralevator extension (MRI Findings) [42 (89.4%)]. In our investigation, a higher percentage of patients [32 (68.1%)] showed no contrast enhancement, which was statistically significant (p=.00044). We demonstrated that the majority of patients had neither secondary tracts nor abscesses, which was statistically significant (p=.00034) in [27 (57.4%)] of the patients. According to our analysis, more patients (32, or 68.1%) did not have supralevator extension (surgical association), and this finding was statistically significant (p<.00001).

Conclusion: When it comes to the diagnosis and pre-operative staging of perianal and anal fistulas, MRI is a crucial diagnostic imaging technique. Particularly in the detection of complex diseases characterized by the development of abscesses, the presence of secondary tracts, and supralevator extension, MRI has proven to be effective. In order to create a good road map and blueprint for an efficient and successful surgical outcome, an MRI examination of the perianal fistula is a crucial imaging modality.