Magnetic-resonance tomography in diagnostics of perianal fistulas

Eligulashvili R. R., Zarodnyuk I. Vl., Shelygin Y. A., Kostarev I.V.

Purpose. To determine the diagnostic value of magnetic resonance imaging in crytogenic peri-anal fistulas. Materials and methods. In the study were included 120 patients with cryptogenic perianal fistulas, the average age was 44.2 ± 3.4 years. All patients underwent magnetic resonance imaging of the pelvic organs with intravenous contrast and diffusion-weighted images. The preoperative MRI data was compared with the intraoperative revision data according to the criteria: the presence of the main fistula tract, the type of fistula, the localization of the inter-nal fistula opening, the presence of additional fistula tract and abscesses of various loca-tions, the involvement of portions of the external sphincter. Results. The sensitivity of MRI in diagnosis of the main fistula tract was 100%; sensi-tivity and specificity in the diagnosis of an additional fistula tract were 95.0% and 97.0%, respectively; sensitivity and specificity in the diagnosis of pararectal abscesses - 87.1% and 90.0%, respectively; sensitivity and specificity in the diagnosis of the internal fistula opening - 94.6% and 33.3%, respectively; sensitivity and specificity in the diagnosis of the external fistula opening were 89.4% and 100%, respectively. The use of intravenous contrast and dif-fusion-weighted images does not increase the diagnostic information of MRI in cryptogenic perianal fistulas. Conclusions. 1. Magnetic resonance imaging is a highly informative diagnostic meth-od for cryptogenic perianal fistulas. 2. Comparative evaluation of different MR scanning se-quences (T2-WI, T2-WI with fat suppression, T1-WI with intravenous contrast, DWI) did not reveal statistically significant differences between them in detecting the main fistulas tract, additional fistula tract, internal and external fistulas opening (p≥0.0125). T2-WI demonstrat-ed higher diagnostic efficacy in assessing the involvement of the external sphincter and in determining the type of fistulas tract, compared to T2-WI with fat suppression, T1-WI with intravenous contrast and DWI (p <0.0125). 3. The main MRI scanning protocol for the study of patients with cryptogenic perianal fistulas includes T2-WI, T2-WI with fat-suppression, DWI. In ambiguous diagnostic situations, after a native MR study, it is possible to add T1-WI with intravenous contrast to the scanning protocol.

1 - State Scientific Centre of Coloproctology, 2 - Russian Medical Acad-emy of Postgraduate Edu-cation. Moscow, Russia.

 

Keywords: magnetic resonance imaging, perianal fistulas, intravenous contrast, diffu-sion-weighted image.

 

Corresponding author:: Eligulashvili R.R. e-mail: Этот e-mail адрес защищен от спам-ботов, для его просмотра у Вас должен быть включен Javascript

 

For citation: Eligulashvili R.R., Zarodnyuk I.V., Shelygin Y.A., Kostarev I.V.Magnetic-resonance tomography in diagnostics of perianal fistulas. REJR 2018; 8 (3):213-226. DOI:10.21569/2222-7415-2018-8-3-213-226.

Received:07.08.18Accepted:29.08.18