Earlier appearance and higher incidence of the rectoanal relaxation reflex in patients with imperforate anus repaired with laparoscopically assisted anorectoplasty

Background: This study aimed to evaluate clinically and manometrically the anorectal function of patients with imperforate anus after repair with laparoscopically assisted anorectoplasty (LAR), as compared with the function of patients after undergoing the conventional method, posterior sagittal anorectoplasty (PSARP). Methods: The defecation status and anorectal manometry of patients with high or intermediate type imperforate anus repaired with LAR (n = 9) and age-matched patients repaired with PSARP (n = 13) were assessed and compared during the first year of postoperative follow-up evaluation. The defecation status was classified by the frequency of bowel openings (<1, 1–4, and >5 times per day). Manometric assessment was performed by an open-tip hydraulic capillary infusion system. The presence of the rectoanal relaxation reflex was determined, and the resting sphincteric pressure and resting rectal pressure were measured. Results: Seven of nine LAR patients had an “acceptable” frequency of one to four bowel openings per day, in contrast to 7 of 13 PSARP patients. The difference in the presentation of daily stooling is not significant (p > 0.05). A positive RAR was detected in 88.9% (8/9) of the LAR patients, and in only 30.8% (4/13) of the PSARP patients (p < 0.01). The presence of a rectoanal relaxation reflex also significantly correlated with an acceptable frequency of bowel opening (1–4 times per day) in both LAR and PSARP patients (p < 0.05). Moreover, a rectoanal relaxation reflex was detected significantly earlier in LAR than in PSARP patients (4.9 ± 1.2 vs 10.1 ± 2.5 months; postoperatively p < 0.0001). Both the LAR and PSARP patients had a similar resting sphincteric pressure (21.5 ± 4.7 vs 25.4 ± 6.2 cm H₂O; p > 0.05). By contrast, the resting rectal pressure was significantly lower in LAR than in PSARP patients (7.7 ± 1.5 vs 11.5 ± 1.3 cmH₂O; p < 0.05). Conclusions: In the early postoperative stage, patients repaired with LAR had more favorable findings in anorectal manometry than patients repaired with PSARP. Long-term follow-up studies to confirm a superior defecation continence achieved with LAR are warranted.