The effect of surgical reconstruction on bladder function in cloacal malformation: A study of urodynamics

Girls with cloacal malformation are at risk of bladder dysfunction, with nearly 90% exhibiting some degree of dysfunction. Surgical dissection, particularly with total urogenital mobilization (TUM), has been hypothesized as a cause of worsening bladder function despite this population commonly having associated vertebral and spinal cord abnormalities that may also explain bladder dysfunction. More recently there has been great effort to select the appropriate surgical technique for cloacal repair in each patient in order to minimize dissection and potential damage to the bladder. We aimed to evaluate the effect of surgical cloacal repair on bladder function based on pre and post-surgery urodynamics (UDS) testing.

A prospectively collected database of patients with anorectal malformation at a single center was queried for girls with cloacal malformations who had undergone surgical repair from 2015 to 2022. It is our current protocol to perform UDS before and after cloacal repair. Only patients who completed both pre and post-surgery UDS were included. UDS were evaluated and classified using the UMPIRE protocol.

A total of 48 patients were included in the cohort. The majority of patients (79.2%) had stable or improved UDS post-op leaving 10 patients (20.8%) who had worsening UDS. Long common channel (≥3 cm) was the only factor significantly associated with worsening UDS. (p = 0.03) Nearly 30% (n = 8) of those undergoing UGS had worse post-op UDS compared to 9.5% (n = 2) with TUM. All patients who worsened UDS initially had safe UDS that changed to intermediate, except for one who worsened to hostile in the setting of significant social challenges and non-compliance. Only common channel length was predictive of worsening UDS, while the type of surgical approach and spine status were not. While the overall risk of worsening UDS after TUM is only 9.5%, patients with normal spines undergoing TUM had the lowest risk, seen in only one in 15 patients (6.6%).

Common channel length was the most significant predictor of worsening UDS, while spine status and surgical technique (TUM vs UGS) did not significantly impact this finding. By following this established surgical protocol based on common channel and urethral lengths, is rare for the surgical cloacal repair to result in worsening post-op UDS, particularly in those undergoing TUM for short common channel and normal spine.