Complementory Value of Sonography in Early Evaluation of Necrotizing Enterocolitis

Despite the widespread use of plain films to detect necrotizing enterocolitis (NEC), it is considered a time-consuming method, which exposes patients to radiation. We aimed to assess changes in ultrasonographic variables and to compare sonograhy and chest radiography in detecting early stages of NEC in suspected premature infants.

This case-control study was carried out in the years 2012-2013. We enrolled 67 premature neonates using a simple sampling method and divided them into the study and control groups. All patients underwent plain abdominal radiography, gray-scale and color Doppler sonography.

34 and 33 neonates were assigned to the study and control groups. No significant gender differences were found between the two groups (P=0.549). The mean bowel wall thickness ranged from 1.2 to 3.2 mm in the control group (132 abdominal quadrants) and 1-3.3 mm in the study group (136 abdominal quadrants, P=0.502). Intra-mural echogenic dots were seen in one neonate in the study group in favour of pneumatosis intestinalis. The mean ±SD bowel wall perfusion in the study and control groups were 3.117±0.975 and 2.878±0.538 dots or lines/cm(2), respectively (P=0.218). One neonate in the study group showed internal echoes within the mild amount of free fluid. Twelve neonates in the control group had minimal amounts of intra-abdominal free fluid.

The two groups differed regarding bowel wall thickness, echogenicity, and perfusion in sonograhy and color Doppler evaluation. Although those differences were not statistically significant, considering the time-consuming nature of abdominal X-ray, the use of sonograhy and color Doppler can improve diagnosis and treatment of NEC as a triage method.