Accuracy of hydrogen peroxide enhanced endoanal ultrasonography in assessment of the internal opening of an anal fistula complex.

Abstract

BACKGROUND:

The aim of this study was to evaluate the accuracy of hydrogen peroxide-enhanced ultrasound in localizing the internal opening of the anal fistula.

METHODS:

A retrospective review of all patients with anal fistula who underwent hydrogen peroxide-enhanced ultrasound was performed. The results of hydrogen peroxideenhanced ultrasound and intraoperative findings on the basis of operative reports were correlated.

RESULTS:

A total of 57 patients (47 men) of mean age of 45.7 (range, 21-77) years underwent hydrogen peroxide-enhanced ultrasound with a diagnosis of anal fistula; 36 patients underwent surgery. The intraoperative internal opening correlated with the hydrogen peroxide-enhanced ultrasound report in 22 of 36 patients (61.1%). In 5 patients, the hydrogen peroxide-enhanced ultrasound yielded false-positive information with a positive predictive value of 84%. Four of the 7 patients with falsenegative hydrogen peroxide-enhanced ultrasound findings had supra- and extrasphincteric fistulas.

CONCLUSIONS:

There is a 61.1% correlation between hydrogen peroxide-enhanced ultrasound and surgical findings of the internal opening with a positive predictive value of 84%. If no internal opening was seen on hydrogen peroxide-enhanced ultrasound, it strongly suggests the possibility of a supralevator or extrasphincteric fistula.

• Authors: I Moscowitz, M K Baig, J J Nogueras, E Ovalioglu, E G Weiss, J J Singh, S D Wexner
• Journal: Techniques in coloproctology (Tech Coloproctol) Vol. 7 Issue 3 Pg. 133-7 (Oct 2003) ISSN: 1123-6337 [Print] Italy
• PMID: 14628155 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Contrast Media
• Hydrogen Peroxide

Topics

• Adult
• Aged
• Contrast Media
• Female
• Humans
• Hydrogen Peroxide
• Male
• Middle Aged
• Rectal Fistula (diagnostic imaging, surgery)
• Retrospective Studies
• Sensitivity and Specificity
• Ultrasonography