Comparison of diagnostic efficacy in males with high/intermediate typed anorectal malformations between ultrasound and inverted X-ray exam

Abstract

Objective To compare the diagnostic efficacy of ultrasound and inverted X-ray in differentiating high and intermediate types of male anorectal malformations (ARMs). Methods A fully paired diagnostic accuracy study was conducted on 146 male children with intermediate/high type ARMs who were treated in our hospital from March 2013 to March 2022. According to their postoperative diagnosis after anorectal plasty, 55 cases (including 12 with bladder-neck fistula and 43 with urethral-prostatic fistula) were assigned into high type group and 91 cases (including 65 with urethral-bulbar fistula and 26 without fistula) into intermediate type group. The accuracy, sensitivity, specificity, and area under the curve (AUC) were used as evaluation indicators to compare the diagnostic efficacy of 2 examinations and the optimal diagnostic cutoff values by receiver operating characteristic (ROC) curve analysis. And the diagnostic efficacy of ultrasound and inverted X-ray was then compared in different time periods after birth. Results Both examinations effectively differentiated high and intermediate types of male ARMs (P < 0.05). The ROC curve analysis showed that the AUC of ultrasound (0.835, 95%CI: 0.764~0.891) was higher than that of inverted X-ray (0.759, 95%CI: 0.681~0.826), though without significant difference (P=0.061). The cut-off value of ultrasound (15.0 mm) was shorter than that of inverted X-ray (24.0 mm). The diagnostic efficacy of ultrasound (0.940, 95%CI: 0.799~0.993) was significant higher than that of inverted X-ray (0.758, 95%CI: 0.578~0.890) when inspection time was longer than 48 h after birth (P=0.032). Conclusion Both ultrasound and inverted X-ray can differentiate intermediate and high type ARMs in male neonates. Ultrasound is more recommended for the neonates older than 48 h.

Keywords

• anorectal malformations
• diagnostic imaging
• ultrasound
• neonate