BackgroundNecrotizing enterocolitis (NEC) is a devastating inflammatory disease of the intestinal tract that represents a significant source of morbidity and mortality in preterm infants. Imaging of the abdomen is valuable for timely diagnosis and close monitoring of disease progression in NEC. Bowel ultrasound (US) is increasingly being recognized as an important imaging tool for evaluating NEC that provides additional detail than plain abdominal radiographs.ObjectiveTo identify bowel US findings associated with surgical management or death in infants with NEC.Materials and methodsWe searched Embase, PubMed, and the Cumulative Index to Nursing and Allied Health Literature for studies investigating the association between bowel US findings and surgical management or death in NEC. Selected articles were evaluated for quality of study methodology using the Newcastle-Ottawa Scale, and aggregate statistics for odds ratio (OR) and 95% confidence interval were calculated.ResultsOf 521 articles reviewed, 11 articles comprising 748 infants were evaluated for quality. Nine of the studies were retrospective and from single-center experiences. Pooled analysis showed that focal fluid collections (OR 17.9, 3.1–103.3), complex ascites (OR 11.3, 4.2–30.0), absent peristalsis (OR 10.7, 1.7–69.0), pneumoperitoneum (OR 9.6, 1.7–56.3), bowel wall echogenicity (OR 8.6, 3.4–21.5), bowel wall thinning (OR 7.11.6–32.3), absent perfusion (OR 7.0, 2.1–23.8), bowel wall thickening (OR 3.9, 2.4–6.1) and dilated bowel (OR 3.5, 1.8–6.8) were associated with surgery or death in NEC. In contrast, portal venous gas (OR 3.0, 0.8–10.6), pneumatosis intestinalis (OR 2.1, 0.9–5.1), increased bowel perfusion (OR 2.6, 0.6–11.1) and simple ascites (OR 0.54, 0.1–2.5) were not associated with surgery or death.ConclusionThis meta-analysis identified several bowel US findings that are associated and not associated with surgery or death in NEC. Bowel US may be useful for early identification of high-risk infants with NEC who may benefit from more aggressive treatment, including surgery. Future studies are needed to determine whether the addition of bowel US in NEC evaluation would improve outcomes.Electronic supplementary materialThe online version of this article (10.1007/s00247-017-4056-x) contains supplementary material, which is available to authorized users.

4. Laryngoscope, 127:1600-1603, 2017.

Radiographic evaluation for necrotizing enterocolitis (NEC) often yields nonspecific findings. Bowel ultrasound (BUS) provides additional information beyond that of abdominal radiographs and may be helpful in the diagnosis of NEC in neonates. We systematically reviewed and aggregated existing literature to get a better estimate of diagnostic accuracy of BUS in the diagnosis of NEC. A literature search was performed using PubMed, Embase, and Cumulative Index to Nursing and Allied Health Literature to identify studies in which infants with clinically suspected NEC were evaluated using BUS. Studies that used modified Bell staging criteria as the reference standard were included. Study quality was assessed, and pooled sensitivity and specificity of various BUS findings for diagnosing NEC were determined. Six articles with a total of 462 patients met eligibility and inclusion criteria. There was heterogeneity in BUS findings evaluated across studies. Ultrasound detection of classic signs of NEC (portal venous gas, pneumatosis, and free air) had pooled sensitivities ranging from 0.27 to 0.48 and pooled specificities ranging from 0.91 to 0.99. Bowel wall thinning and absent peristalsis had overall low sensitivity (0.22 and 0.30) but high specificity (0.96 and 0.96) for NEC. Assessment of abdominal fluid, which included ascites and focal fluid collection, also had overall low sensitivity and high specificity (simple ascites: 0.45 and 0.92; focal fluid collection: 0.19 and 0.98). In summary, individual BUS findings have low sensitivity and high specificity for diagnosis of NEC. Bowel ultrasound may be a useful adjunct to plain abdominal radiographs in the evaluation of infants with clinical suspicion of NEC.

Sinusoidal obstruction syndrome (SOS) is a potentially fatal complication of hematopoietic stem cell transplantation (HSCT). Traditional ultrasound (US) has poor sensitivity and specificity. US shear wave elastography (SWE) is a newer technology that measures liver stiffness. This is a single-institution, prospective cohort study evaluating SWE in patients younger than 21 years who received HSCT from December 2015 through June 2017. SOS was defined using the modified Seattle criteria. Subjects had US with SWE at three scheduled time points. t-tests were used to assess for difference between the groups and ROC curves were generated. Twenty-five patients were included. Five subjects developed SOS. At day +5 HSCT, SOS patients had SWE velocities that increased by 0.25 ± 0.21 m/s compared to 0.02 ± 0.18 in patients without SOS (p = 0.020). At day +14, SOS patients had SWE velocities that significantly increased by 0.91 m/s ± 1.14 m/s compared to 0.03 m/s ± 0.23 m/s in patients without SOS (p = 0.010). SWE SOS diagnosis occurred on average 9 and 11 days before clinical and conventional US diagnosis, respectively. Patients who develop SOS have increased liver stiffness compared to patients who do not develop SOS. SWE changes occur before other imaging and clinical findings of SOS.

Ultrasound is one of the most important imaging modalities in pediatric imaging because of its accessibility, portability, lack of ionizing radiation, and ability to generally perform examinations without need for sedation. Ultrasound elastography can measure the stiffness of various tissues. This review article aims to discuss how ultrasound elastography has performed in evaluating multiple pathologies in the pediatric population. The best studied pediatric applications are in liver diseases such as fibrosis, biliary atresia, and hepatic vascular congestion. Measuring muscle stiffness in cerebral palsy is the most promising pediatric musculoskeletal application, but many other applications are in the early stages of research. Other applications in pediatric small organ imaging have been explored and still need more study before gaining clinical relevance.