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The fistula tract measures approximately 1.2 cm, originating from the left perianal area and extending upward between the internal and external anal sphincters, opening into the anal canal at the 12 o'clock position. The internal opening of the fistula is located about 8 mm from the anal verge. The fistula shows strong enhancement after contrast injection, with an associated fluid collection (abscess) at the left perianal margin. The fluid shows restricted diffusion and peripheral enhancement.