Fig. 1From: Accuracy of magnetic resonance imaging in defining dentate line in anal fistulaSchematic diagram of clock positioning method for anal fistula. A The front center is 12 points, the rear center is 6 points, the left center is 3 points, and the right center is 9 points. B The internal opening of anal fistula is at 6 o’clock (shown by the black arrow)Back to article page