Dynamic MRI (dMRI) as a guide to therapy in children and adolescents with persistent full thickness rectal prolapse: a single centre review.

Introduction: Full thickness rectal prolapse (FTRP) tends to be self-limiting in children and is usually managed expectantly. However, it may persist and therefore requires surgical correction. There is no consensus upon operative management, and no one procedure has uniformly good outcomes. The aim of this study was to determine whether pre-operative diagnostic dMRI findings might help identify the operative approach best suited to the anatomical abnormality of the individual child.

Methods: A retrospective review of ten children with persistent FTRP who had been evaluated pre-operatively with dMRI between 2002 and 2010 was performed. In this preliminary work, MRI findings were not used to direct surgical management. Data collected included: age at presentation, underlying medical conditions, timing and findings of dMRI (specifically, descent of rectum from pubococcygeal (PC) line on straining), timing and type of surgery, surgical outcomes, and length of follow-up.

Results: Ten children (two female) with a median age of 11 years 2 months (range 8-15 years) with FTRP refractory to conservative treatment underwent diagnostic pre-operative dMRI. Median perineal descent from PC line on straining during dMRI was 3.5 cm (range 1-4 cm). Three of the seven children with severe descent initially underwent a Delorme's procedure, and all required surgical revision. Five with severe descent and one with moderate descent achieved a cure following rectopexy. Two patients with mild descent underwent a Delorme's procedure. One achieved a cure, and the other developed recurrence. Of the ten patients, seven had no prolapse at the last clinic review, and three have persisting symptoms. Median follow-up was 3.5 years (range 1-6).

Conclusion: The findings from this small study favour rectal suspension techniques for surgical management of moderate to severe perineal descent on dMRI. Delorme's procedure should only be applied to those with mild descent. Pre-operative dMRI assessment may have a potential role in guiding surgical intervention for children. However, future prospective studies will be required to confirm this assertion.