Lasting impact on children with an anorectal malformations with proper surgical preparation, respect for anatomic principles, and precise surgical management

Surgical Simulation of Posterior Sagittal Anorectoplasty for Rectovestibular Fistula: Low-Cost High-Fidelity Animal-Tissue Model

PURPOSE

To provide a high-fidelity, animal tissue-based model for the advanced surgical simulation of a Posterior Sagittal Anorectoplasty (PSARP) for rectovestibular fistula in anorectal malformation (ARM).

MATERIALS AND METHODS

A chicken cadaver was used to assess the feasibility of simulating a PSARP for rectovestibular fistula in ARM. No modification was required to implement the surgical simulation.

RESULTS

A detailed description of the high-fidelity surgical simulation model is provided. The PSARP can be simulated while providing realistic anatomy (e.g. common wall between rectovestibular fistula and vagina), adequate rectal size, location and placement of the rectovestibular fistula, and proximity to the vagina. Haptic conditions of the tissue resemble human tissue and operative conditions as well.

DISCUSSION

Concerning the decreased exposure of index cases of pediatric surgical trainees and pediatric surgeons in practice, simulation-based training can provide means to acquire or maintain the necessary skills to perform complex surgical procedures [1-5] Surgical simulation models for ARM are limited. Few low-cost trainers are available with predominant artificial and mostly unrealistic tissue [6-8] Animal models have the advantage of realistic multilayer tissue haptic feedback [6].

CONCLUSION

We provide a low-cost, high-fidelity model for correcting a rectovestibular fistula in a child with ARM, a complex operative procedure with low incidence but high-stake outcomes. The described tissue model utilizing the chicken cloaca anatomy provides a high-fidelity model for operative correction of rectovestibular ARM. For simulation purposes in the treatment of ARM, this model appears to be promising in terms of providing realistic pathology and haptic feedback in pediatric dimensions.

LEVEL OF EVIDENCE

V.

Preoperative fistula diagnostics in male anorectal malformations after colostomy: a single-center experience

BACKGROUND

Accurate preoperative fistula diagnostics in male anorectal malformations (ARM) after colostomy are of great significance. We reviewed our institutional experiences and explored methods for improving the preoperative diagnostic accuracy of fistulas in males with ARMs after colostomy.

METHODS

A retrospective analysis was performed on males with ARMs after colostomy admitted to our hospital from January 2015 to June 2022. All patients underwent magnetic resonance imaging (MRI) and high-pressure colostogram (HPC) before anorectal reconstruction. Patients with no fistula as diagnosed by both modalities underwent a voiding cystourethrogram (VCUG). General information, imaging results and surgical results were recorded.

RESULTS

Sixty-nine males with ARMs after colostomy were included. Age at the time of examination was 52 ~ 213 days, and the median age was 89 days. The Krickenbeck classification according to surgical results included rectovesical fistula (n = 19), rectoprostatic fistula (n = 24), rectobulbar fistula (n = 19) and no fistula (n = 7). There was no significant difference in the diagnostic accuracy between MRI and HPC for different types of ARMs. For determining the location of the fistula, compared to surgery, HPC (76.8%, 53/69) performed significantly better than MRI (60.9%, 42/69) (p = 0.043). Sixteen patients diagnosed as having no fistula by MRI or HPC underwent a VCUG, and in 14 patients, the results were comfirmed. However, there were 2 cases of rectoprostatic fistula that were not correctly diagnosed.

CONCLUSION

High-pressure colostogram has greater accuracy than MRI in the diagnosis of fistula type in males with ARMs after colostomy. For patients diagnosed with no fistula by both methods, VCUG reduces the risk of false-negative exclusion, and rectoprostatic fistula should be considered during the operation.