The Value of Colorectal Filling Contrast Ultrasonography in Diagnosing Paediatric Juvenile Polyps

Abstract

Objectives: To describe a facilitated procedure of colorectal filling contrast ultrasonography (CFCUS) and investigate its potential role in the assessment of paediatric juvenile polyps. Methods: The general information, clinical symptoms, ultrasound image characteristics, and colonoscopy findings of 101 children with clinical signs of colorectal polyps admitted to our hospital between May 2018 and May 2021 were retrospectively reviewed. All children underwent conventional transabdominal ultrasonography (CTUS), and CFCUS before colonoscopy, and the latter served as the gold standard. Chi-squared tests and Mann-Whitney U tests were used for the statistical analysis. Results: Forty-five children with fifty-two colorectal polyps were diagnosed by colonoscopy. Ten polyps had false-negative results on CTUS, six of which were detected by CFCUS. The sensitivity, specificity, positive predictive value, and negative predictive value of CFCUS vs CTUS was 92.3% vs 80.7%, 100% vs 100%, 100% vs 100%, 93.3% vs 84.8%, respectively. The maximum diameter of polyps (mean ± standard deviation) missed by CTUS was significantly smaller than that detected by CTUS (7.50±2.12 mm [range 4–12 mm] vs. 19.62±7.89 mm [range 6–41 mm], P<0.0001). A significant difference was observed between CTUS and CFCUS. The difference between CTUS and CFCUS regarding the detection rate of polyps with a diameter < 1 cm (P=0.031). A statistical difference was observed in the detection rate of polyps (P=0.031), and pedicles (P<0.001) between CTUS and CFCUS. The Kappa values for the assessment of Yamada’s classification between CTUS and colonoscopy and CFCUS and colonoscopy were 0.51 and 0.84, respectively. Six colonic polyps were accompanied by a punctate hyperechoic area on the surface, which may be suggestive of a correlation with erosion and bleeding findings.Conclusion: CFCUS can increase the detection rate of polyps and pedicles, especially polyps with diameters <1 cm, and accurately evaluate Yamada’s classification, providing useful preoperative information for colonoscopy.