CASE 2120 Published on 15.01.2003

Recto-vaginal fistula: radiographic findings

Section

Abdominal imaging

Case Type

Clinical Cases

Authors

V. Cantisani, A. Blandini, P. Cavallo, G. Galanti, E. Pagliara

Patient

34 years, female

Clinical History
The patient presented with passage of flatus and stool through the vagina, vaginal discharge and a history of recurrent resistant vaginitis.
Imaging Findings
The patient presented with passage of flatus and stool through the vagina, vaginal discharge and a history of recurrent resistant vaginitis. For further evaluation proctography and vaginography were performed, which clearly showed the presence of a recto-vaginal fistula.
Discussion
Ano-vaginal and recto-vaginal fistulas are epithelium-lined communications between the anus or rectum and the vagina. They are relatively rare and account for approximately 5% of all anorectal fistulas. Major causes are obstetric or surgical trauma, inflammation such as Crohn's disease or postoperative infection, and radiotherapy. The symptoms of vaginal fistulisation are dramatic and disconcerting to the patient. Patients may present with symptoms of passage of flatus and stool through the vagina, vaginal discharge, foul smelling air, or recurrent vaginitis.

Findings based on a patient's clinical history and physical examination are often inconclusive, and imaging is performed to establish the location and course of the fistula tract. A variety of imaging techniques have been introduced that are useful in the workup of patients with ano-vaginal and recto-vaginal fistulas, but reports in the literature concerning these techniques are sporadic. Initially, only proctography and vaginography were available. Methylene blue introduced into the rectum may demonstrate a vaginal communication, but this method often misses high communications. Vaginography and colpography have been advocated by some authors as additional methods for detecting vaginal fistulas. However, even direct examination of the bladder with cystoscopy or of the colon with colonoscopy may fail to identify a communication site. The sensitivity of proctography has been reported to be only 34%. In a relatively large study of 27 patients, the results for vaginography were better than those for proctography, with 19 of the 24 fistulas detected (sensitivity, 79%). This superiority of vaginography has been attributed to the use of an occluding vaginal balloon. During proctography, the preferential flow will often be towards the proximal colon, whereas during vaginography, the flow is towards the vagina. The disadvantage of balloon vaginography is that the balloon occludes the opening of low fistula tracts. The drawbacks of both barium enemas and vaginography are that the relation of the fistula tract to the anal sphincter is difficult to appreciate and the extent of anal sphincter defects cannot be identified. Vaginal fistulas can be identified on CT. The more subtle abnormalities in ano-vaginal and recto-vaginal fistulas often make these fistulas more difficult to detect on imaging. Often no major inflammation is present, and the short thin-walled tract is collapsed because of the free communication with the vagina. The identification of air in the vaginal septum is an important sign for the identification of ano-vaginal and recto-vaginal fistulas. More recently, MR imaging has been proposed for use in the work-up of patients with recto-vaginal fistulas.

Differential Diagnosis List
Recto-vaginal fistula
Final Diagnosis
Recto-vaginal fistula
Case information
URL: https://www.eurorad.org/case/2120
DOI: 10.1594/EURORAD/CASE.2120
ISSN: 1563-4086