Endorectal Three-dimensional Ultrasound in the Diagnosis of Cryptogenic Fistulas of the Rectum.

A linear transrectal ultrasonic sensor with a frequency of 9 MHz is inserted into the rectum lumen to a depth of 10 cm from the edge of the anus. In real time, the rectal wall and anatomical structures of the anal canal are evaluated using linear sections. The localization of the internal fistula opening, the course of the fistula relative to the fibers of the external sphincter and the presence or absence of cellular and wall plug is determined.

A mechanical circular transrectal ultrasonic sensor with a frequency of 13 MHz is inserted into the rectum lumen to a depth of 10 cm from the edge of the anus. Within 30 seconds with a scan interval of 2 mm with a length of 10 cm, a circular recording of the anatomical structures of the rectum, surrounding tissue and anal canal takes place, obtaining an array of images in the form of a cube. The study was completed. After, at a convenient time for the researcher is working with a three-dimensional array of images. The resulting cube can be rotated 360 degrees in a circle of its axis, work with the sagittal, frontal and axial plane. To obtain a more visual representation of the exact localization of the internal fistula orifice, the course of the fistula relative to the fibers of the outer sphincter and to design volumetric cellular and wall plug.