Endosonography in the diagnosis of recurrent anal fistulas

Abstract

Background. The aim of this work was to compare non-contrast endosonography (NCE) and contrast-enhanced endosonography (CEE) in the diagnostics of recurrent anal fistulas.

Methods. In the years 1999-2002 we diagnosed 148 patients with anal fistulas. Fifty-one out of this group had recurrent anal fistulas, remaining had primary disease. For anal endosonography a Bruel&Kjaer scanner with 7.0 MHz transducer was used and 3% solution of hydrogen peroxide was used for CEE. In each case, NCE was followed by CEE, and results of both methods were compared.

Results. The difference of percentages of correct diagnoses between NCE and CEE carried out 35.29% in a group of patients with recurrent anal fistulas (95% confidence interval 50.5% - 20.09%); while the difference in a group of patients with primary anal fistulas was only 4.55% (95% confidence interval 11.09% - 2.00%).

Conclusions. CEE significantly improves the efficiency of endosonography in diagnosing recurrent anal fistulas, whereas in primary fistulas the value of NCE and CEE is comparable.