Contrast-enhanced endoanal and transperineal sonography in perianal fistulas.
OBJECTIVE
To improve the diagnostic potential of ultrasound in patients with perianal fistulas, by performing a combined perineal and endorectal Doppler sonography investigation before and after contrast enhancement with hydrogen peroxide.


METHODS
Ten patients (9 male and 1 female) with perianal fistulas were tested. After contrast-free transperineal and endoanal sonography, hydrogen peroxide was injected in the fistulas and the ultrasound examinations were repeated.


RESULTS
All fistulas were identified by conventional endoanal and transperineal sonography. The contrast application gave more detailed information about the location of the fistula in relation to the anal lumen and sphincters. The fistulas were distributed as follows: intersphincteric - in 5 patients, transsphincteric - in 2 and extrasphincteric complicated (with 1 or more secondary tracks) fistula - in 3 patients. The findings have been confirmed intraoperatively in 9 patients that underwent an operation. Hypervascularization of the wall was detected in 4 patients by means of Doppler investigation which also differentiated arterial blood flow in 3 cases and venous blood flow in one.


CONCLUSIONS
The application of the contrast-enhanced endoanal and transperineal sonography offers a more detailed perianal fistula imaging. In addition the Doppler technique can further characterize their blood supply.
Tsankov
Tsanko
T
National Multiprofile Transport Hospital Tsar Boris III, Clinic of Surgery, Sofia, Bulgaria. tstsankov@mail.bg
Tankova
Ludmila
L
Deredjan
Hayrabed
H
Kovatchki
Daniel
D
D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D006861:Hydrogen Peroxide; D007089:Image Enhancement; D008297:Male; D008875:Middle Aged; D012003:Rectal Fistula / Q000000981:diagnostic imaging*; D018608:Ultrasonography, Doppler
D006861:Hydrogen Peroxide