Application of two-dimensional ultrasound combined with three-dimensional imaging technology in the diagnosis of anal fistula

Abstract

Objective To evaluate the clinical value of the real-time three-dimensional ultrasound in the diagnosis of the fistula-in-ano. Methods One hundred and eighteen fistula-in-ano patients were examined using conventional and three-dimensional ultrasound, the stereotaxis of interal opening and the shape of the fistula-in-ano were analyzed. Then the diagnosis results of ultrasound were compared with the surgery and pathology. Results In 118 patients, the accuracy of preoperative identifying internal opening by two-dimensional ultrasound was 85%, and 95% for three-dimensional ultrasound with statistically significant difference (χ2=6.679, P<0.05). For complex anal fistula, the diagnostic accuracy rates of main fistula tract by three-dimensional ultrasound (100%, 82/82) was higher than that by two-dimensional ultrasound(95%, 78/82), the difference was statistically significant (χ2=4.100, P<0.05). In 82 cases of complex anal fistula, the diagnostic accuracy of branch fistula tract by two-dimensional ultrasound was 70% (57/82), the accuracy using three-dimensional ultrasound was 89%(73/82), there was statistically significance (χ2=9.499, P<0.05). Conclusions Three-dimensional ultrasound can accurately locate the interal opening of fistula-in-ano and determine the shape of fistula-in-ano, which provided the most intuitive information for clinical treatment and had high practical value. Key words: Ultrasonography; Rectal fistula