Jae-Yeon Hwang MD, Presenter: Nothing to Disclose

Hye-Kyung Yoon MD, Abstract Co-Author: Nothing to Disclose

Yeoun Joo Lee, Abstract Co-Author: Nothing to Disclose

Young Ah Cho, Abstract Co-Author: Nothing to Disclose

Chong Hyun Yoon, Abstract Co-Author: Nothing to Disclose

Jin Seong Lee MD, Abstract Co-Author: Nothing to Disclose

Kyung Mo Kim, Abstract Co-Author: Nothing to Disclose

Perianal disease is relatively common in Asian children with Crohn’s disease and MR has been known as the best modality for depicting fistulas. Endorectal ultrasound has been used in some cases but limited due to relative invasiveness. The purpose of this study was to assess usefulness and feasibility of transperineal ultrasound (TPUS) to show perianal fistulas and abscesses in pediatric Crohn’s disease.

A total of 25 TPUS examinations were performed in 20 consecutive patients with Crohn’s disease and perianal fistulas. There were 14 boys and six girls (14.4 ± 1.6 years; range, 10–17 years). All examinations were requested by pediatric gastroenterologists to evaluate the status of fistulas and possible abscess formation. It was undergone through perianal soft tissue using 8-5 MHz curvilinear or 12-5 MHz linear transducers on IU-22 ultrasound system (Philips Medical Systems, Bothell, WA). The endpoints of our study consisted of degree of pain, location and activity of fistula, presence or absence of abscess, and anal canal inflammation. Patients were asked to describe pain during examination. The locations of perianal fistulas were categorized in eight directions in relation to the anal opening. Active state of fistula was defined when the lesion showed hyperemia on color Doppler study with or without air bubble on gray-scale image.

Total 27 fistulas were identified in 25 TPUS examinations. All TPUS were performed successfully and well-tolerated. 11 (50.0%) patients did not complain any pain or tenderness related to TPUS and 9 (40.9%) responded with mild pain. The most common location of fistula was left anterior direction of the anal opening. Active fistulas were 19 out of 27: all of which showed hypervascularity and five of which contained air bubbles. Abscesses were found in five patients and all of them were accompanied with active fistulas. Anal canal hyperemias were presented in 11 patients and 10 of them had active fistulas.

The preliminary results showed that TPUS was fairly good to visualize anorectal canal and identify fistulas and abscesses. TPUS could be a good adjunctive or alternative method to MRI or endorectal ultrasound.

TPUS can be not only a simple and non-invasive screening tool for pediatric perianal Crohn’s disease, but also a useful imaging modality for follow up evaluation.

Hwang, J, Yoon, H, Lee, Y, Cho, Y, Yoon, C, Lee, J, Kim, K, Transperineal Ultrasound (TPUS) for Evaluating Perianal Fistulas in Pediatric Crohn’s Disease: Preliminary Report.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12022451.html