Anal endosonography is useful for postoperative assessment of anorectal malformations

Abstract

Aim This study aimed to develop and evaluate a scoring system for anal endosonography to assess anal canal structures after repair of anorectal malformations (ARM). Methods Forty patients with ARM aged 16 years (range, 1-22 years) and 20 controls aged 17 years (range, 0.5-20 years) were examined. Anal function was assessed clinically and by anal canal manometry. The anal canal structures were imaged by anal endosonography using a 7.5-MHz transducer. A scoring system was developed to assess the anal sphincters as visualized on the endosonographic images. Results Continence was significantly correlated to anal canal pressures. The estimated extent of muscle defect (measured in quadrants) and the number of disruptions in the internal and external anal sphincters correlated significantly to the rest and squeeze pressures, respectively. Thus, patients (>4 years) with squeeze pressure of less than 80 cm H 2O were characterized by more than 1 disruption in the external anal sphincter ring and 2 or more quadrants with scar tissue. Conclusion The extent of scar tissue and the number of disruptions in the anal sphincters correlate with anal canal pressures and continence after ARM repair. Anal endosonography may be used to study the results after different surgical techniques and for prognosis on continence in patients with ARM.