To evaluate an alternative route of pelvic abscess drainage in children via a transiliopsoas approach.

Appendiceal perforations complicated by inflammatory masses, such as abscesses or phlegmon, are a common indication for abdominal drainage in pediatric interventional radiology. Certain locations of collections may present particular challenges for the operator, owing to numerous surrounding structures, including bowel and other pelvic anatomy. This series describes an alternative route for drainage, which involves traversing the iliopsoas muscle under US guidance to drain a deep pelvic abscess.

Retrospective chart review was performed of the transiliopsoas approach for abscess drainage during a 5-year period. The technique, pre- and post-drainage imaging, aspiration/drain output, duration of catheter dwell, procedure-related complications and abscess recurrence were reviewed.

Transiliopsoas needle placement was successful in 14 of 14 patients (100%). Catheter placement was successful in 13 patients. Abscess wall rupture precluded catheter placement in one patient. Mean catheter duration was 4.9 days, with a range of 2 to 9 days. Clinical improvement was achieved in all 14 patients (100%). There were no major complications. Post-procedure pain with ambulation was reported in 3 of 14 patients (21.4%), which was successfully controlled in each case with medication, and resolved after 2 days.

The transiliopsoas route is a safe and effective route for US-guided abscess drainage and catheter placement in children with deep pelvic collections. In selected cases, this approach provides a more easily accessible and safer route than more traditional interventional approaches.