Association of Preoperative Ultrasonography with Long-Term Prognosis in Low-Type Anorectal Malformations: A Retrospective Cohort Study

Purpose We aimed to investigate the relationship between the distal rectal pouch and perineum (P–P distance), measured via preoperative ultrasonography, and the Japanese Society of Gastrointestinal and Anorectal Anomalies (JSGA) score at 4 years of age in patients with low-type anorectal malformations. Methods This retrospective cohort study involved 47 pediatric patients diagnosed with low-type anorectal malformations and treated at the Saitama Children’s Medical Center between 2006 and 2020. The P–P distance was measured on the first/second day of life using transperineal ultrasonography. Postoperative defecation function was evaluated using the JSGA score at 4 years of age. Simple and multiple regression analyses (dependent variable: JSGA score at 4 years of age; independent variables: P–P distance, spinal cord disease, and lumbosacral disease) were used to determine associations between the P–P distance and defecation outcomes. Results A shorter P–P distance was significantly associated with better defecation function, as indicated by higher JSGA scores. Specific JSGA parameters (e.g. soiling and incontinence severity) were correlated with the P–P distance. Lumbosacral disease affected defecation outcomes. Conclusion The P–P distance may determine the postoperative prognosis of low-type anorectal malformations. A smaller P–P distance indicates better postoperative defecation function.