Magnetic resonance imaging of the anal sphincter and spine in patients with anorectal malformations after posterior sagittal anorectoplasty: a late follow-up cross-sectional study

Evaluation of Anal Sphincter with High Resolution Anorectal Manometry and 3D Reconstruction in Patients with Anorectal Malformation

BACKGROUND

Patients with anorectal malformation (ARM) need long-term follow-up, in order to evaluate fecal continence; the main predictors of longer-term success are the type of ARM, associated anomalies and sacral integrity. Three-Dimensional High Resolution Anorectal Manometry (3D-HRAM) gives detailed information on pressure on the anal complex profile. Our objective was to analyze anal sphincter activity in ARM patients with 3D-HRAM establishing the correlation between manometric and clinical data.

METHODS

Forty ARM patients were submitted to 3D-HRAM: manometric, anatomical and clinical scores were correlated with each other and with the bowel management response (BM).

RESULTS

A positive correlation between all scores and types of ARM was found: in high ARM and in patients with spinal anomalies (regardless to ARM type) lower scores were reported and even after BM they did not achieve good continence.

CONCLUSIONS

3D-HRAM gives detailed data on the functional activity of the anal sphincter complex. Our study revealed a correlation between manometric parameters and clinical outcomes, confirming spinal malformations and ARM type as the most important prognostic risk factors for a bad outcome. Specific sphincteric defects can also be explored with manometry, allowing for tailored bowel management strategies.

Analysis of the efficacy of biofeedback for faecal incontinence after surgery for anorectal malformation

OBJECTIVE

To explore the therapeutic effects of biofeedback in the treatment of faecal incontinence (FI) after surgery for anorectal malformation (ARM).

METHODS

Clinical data were collected from paediatric patients for postoperative biofeedback due to FI caused by ARM between May 2017 and November 2021. The data included the duration of symptoms, the integrity of the anal sphincter, anorectal manometry parameters, and FI scores. These patients were divided into the low ARM group (group A) and the high ARM group (group B).

RESULTS

A total of 45 paediatric patients were enrolled in the study. There were 28 cases in group A and 17 cases in group B. The differences in age, gender, and body weight were not statistically significant between the two groups (p > 0.05). The differences in the clinical indicators were also not statistically significant between the two groups at the time of the initial evaluation. The duration of symptoms was 2.21 ± 0.71 years and 4.14 ± 1.89 years in groups A and B. There were 16 cases with an intact anal sphincter in group A and only two cases with an intact anal sphincter in group B. This difference was statistically significant between the two groups (p < .05). The anal resting pressure, initial sensitivity threshold, defaecation sensitivity threshold, defaecation urge threshold, and FI scores were significantly improved in both groups post-treatment compared to pre-treatment (p < .001). Strong impulses improved significantly in group A, while strong impulses did not improve significantly in group B. The multivariate logistic regression analysis with these variables further showed that symptom duration and anal sphincter integrity were the main factors influencing the therapeutic effects of biofeedback.

CONCLUSION

Biofeedback plays a positive role in the treatment of FI in paediatric patients following surgery for ARM. Symptom duration and anal sphincter integrity were found to be the main factors influencing the therapeutic effect of biofeedback.

Image-guided confirmation of a precision pull-through procedure during laparoscopically assisted anorectoplasty in an open MRI operating theater: first application in an infantile case with anorectal malformation

Background

Image-guided surgery with an open magnetic resonance imaging (MRI) system is applied for brain tumors in the neurosurgery field, but has rarely been reported in pediatric surgery. We report our initial experience of intraoperative confirmation of precision rectal pull-through during laparoscopically assisted anorectoplasty (LAARP) in an open MRI operating theater for pediatric patients with anorectal malformation (ARM).

Case presentation

A 3.0 kg term male neonate was delivered with anorectal malformation. An invertogram revealed the intermediate type. Transverse colostomy was made on the left upper abdomen. The recto-bulbar urethral fistula (RBUF) was diagnosed by a distal colostogram and voiding cystourethrogram. LAARP was planned at 6 months of age. Because this was the first procedure in which the pediatric abdomen had been scanned in an open MRI operating theater in our institution, we scanned his pelvic floor under sedation 3 weeks before the operation using the open MRI system in our operation room. We performed the operation with 4 trocars. The peritoneal reflection was carefully incised and the rectum was dissected. The RBUF was resected. The center of the muscle complex was detected at the perineal skin with an electrical nerve stimulator, and a 7-mm longitudinal skin incision was made on the perineal lesion for anoplasty. The muscle complex and the pubo-rectal sling were confirmed laparoscopically using a 3.5-mm bipolar forceps connected to the electrical nerve stimulator. Anoplasty was performed between the rectal stump and perineal skin. After anoplasty, the patient was scanned with open MRI under general anesthesia. We attached the quadrature-detection (QD) head coil around the patient’s pelvis and inserted him in the gantry. A 0.45-T open MRI clearly revealed that the pulled through rectum was located in the center of the muscle complex on T2-weighted images. The postoperative course was uneventful. Oral intake was started on post-operative day 1. Postoperative dynamic urography showed no complication (e.g., leakage or residual fistula).

Conclusions

We successfully performed LAARP for ARM, with intraoperative confirmation of precision rectal pull-through in an open MRI operating theater. Further cases are required to evaluate the application of open MRI systems in pediatric surgery.