Aim :

To determine the diagnostic accuracy of three dimensional ultrasound in cases of perianal fistula compared to intra-operative findings during surgical procedure.

Background:

Perianal fistulae can be either low type (simple) or high type (complex) and surgical treatment options differ accordingly. Preoperative three-dimensional endoanal ultrasonography (3D-EAUS) is a promising diagnostic technique that can effectively assist in choosing the most suitable treatment option for patients with anal fistula by providing the surgeon with accurate outlining of the fistula.

Methods:

The study is a cross sectional comparative study conducted at Al-Sadr Medical City during the period from September 2018 through September 2019, and included cases with fistula in ano, which were subjected to 3-D ultrasound, then followed up during surgery to obtain the intra-operative findings of the fistula.

Results:

The study included (78) patients whom their age ranged from (18-65) years. Majority of cases were males (79.49%). For assessing the concordance between 3D-EAUS and the intraoperative findings the Kappa coefficient for the internal opening was 0.9825 (P-value < 0.001), for the external opening was 0.9853 (P-value < 0.00), For the course of primary tract, Kappa = 0.9754 (P-value < 0.001) and for the course of the extension tract was 0.9761 with a P-value of < 0.001.

Conclusions:

Three-dimensional endoanal ultrasound is an effective and dependable tool for delineation the course of a perianal fistula.