The comparison of magnetic resonance and fluoroscopic imaging options in the preoperative assessment of boys with anorectal malformations and a colostomy.

BACKGROUND: In recent decades, magnetic resonance imaging (MRI) has gained prominence as a standard diagnostic method for preoperative assessment in patients with anorectal malformations and a colostomy, with the potential to replace the classic fluoroscopic distal pressure colostogram (FDPC). Three MRI techniques are available: MRI-distal pressure colostogram with gadolinium (MRI-DPCG) or saline (MRI-DPCS) instillation into the colostomy and native MRI without colostomy instillation. OBJECTIVE: To evaluate and compare the diagnostic accuracy of MRI (native MRI, MRI-DPCG and MRI-DPCS) in the preoperative workup of boys with an anorectal malformation and a colostomy and to compare it to FDPC. MATERIALS AND METHODS: Sixty-two boys with preoperative MRI using one of the three approaches and 43 with FDPC met the inclusion criteria for this retrospective study. The presence and localization of rectal fistulas according to the Krickenbeck classification were evaluated and compared with intraoperative findings. RESULTS: The accuracy of fistula detection for MRI in general (regardless of the technique), MRI-DPCS, MRI-DPCG, native MRI and FDPC was 95% (59/62, P<0.001), 100% (12/12, P=0.03), 100% (30/30, P<0.001), 85% (17/20, P=0.41) and 72% (31/43, P=0.82), respectively. The accuracy of describing fistula type in patients with a correctly detected fistula using these methods was 96% (45/47, P<0.001), 100% (9/9, P<0.001), 100% (23/23, P<0.001), 87% (13/15, P<0.001) and 67% (13/21, P=0.002), respectively. CONCLUSION: MRI is a reliable method for detecting and classifying fistulas in boys with an anorectal malformation and a colostomy and can be considered the modality of first choice for preoperative workup.

Anastomotic stricture prediction in patients with esophageal atresia with distal fistula.

PURPOSE: To investigate potential early risk factors for anastomotic stricture formation and assess the predictive role of post-operative esophagrams. METHODS: A retrospective study of patients with esophageal atresia with distal fistula (EA/TEF) operated between 2011 and 2020. Fourteen predictive factors were tested for stricture development. Esophagrams were used to calculate early (SI1) and late (SI2) stricture index (SI = anastomosis diameter/upper pouch diameter). RESULTS: Of 185 patients operated for EA/TEF in the 10-year period, 169 patients met the inclusion criteria. Primary anastomosis was performed in 130 patients and delayed anastomosis in 39 patients. Stricture formed in 55 patients (33%) within 1 year from anastomosis. Four risk factors showed strong association with stricture formation in unadjusted models: long gap (p = 0.007), delayed anastomosis (p = 0.042), SI1 (p = 0.013) and SI2 (p < 0.001). A multivariate analysis showed SI1 as significantly predictive of stricture formation (p = 0.035). Cut-off values using a receiver operating characteristic (ROC) curve were 0.275 for SI1 and 0.390 for SI2. The area under the ROC curve demonstrated increasing predictiveness from SI1 (AUC 0.641) to SI2 (AUC 0.877). CONCLUSIONS: This study identified an association between long gap and delayed anastomosis with stricture formation. Early and late stricture indices were predictive of stricture formation.