The impact of high-frequency transducers on the sonographic measurements of the pyloric muscle thickness in infants.

BACKGROUND: Ultrasound is the modality of choice for the diagnosis of hypertrophic pyloric stenosis (HPS). The evolution of high-frequency transducers in ultrasound has led to inconsistent ways of measuring the pylorus. OBJECTIVE: To standardize the measurements and evaluate the appearance of the normal and hypertrophied pylorus with high-frequency transducers. MATERIALS AND METHODS: We retrospectively analyzed abdominal ultrasounds of infants with suspected HPS from January 2019-December 2020. We classified the layers of the pylorus while assessing the stratified appearance. Two pediatric radiologists measured the muscle thickness of the pylorus independently by two methods for interrater agreement. Measurement (a) includes the muscularis propria and muscularis mucosa. Measurement (b) includes only the muscularis propria. We also evaluated the echogenicity of the muscularis propria. The interrater agreement, mean, range of the muscle thickness, and the diagnostic accuracy of the two sets of measurements were calculated. RESULTS: We included 300 infants (114 F:186 M), 59 with HPS and 241 normal cases. There was a strong agreement between the readers assessed in the first 100 cases, and ICC was 0.99 (95% CI, 0.98-0.99). Measurement (a), median thickness is 2.4 mm in normal cases and 4.8 mm in HPS. Measurement (b), median thickness is 1.4 mm in normal cases and 4.0 mm in HPS. Measurement (a) has an accuracy of 89.7% (95% CI, 85.7-92.8%) with 98.3% sensitivity and 87.6% specificity. Measurement (b) has an accuracy of 98.0% (95% CI, 95.7-99.3%) with 89.8% sensitivity and 100.0% specificity. The pylorus stratification is preserved in all normal cases and 31/59 (52.5%) cases of HPS. There was complete/partial loss of stratification in 28/59 (47.5%) cases of HPS. In all HPS cases, the muscularis propria was echogenic. CONCLUSION: Measuring the muscularis propria solely has a better diagnostic accuracy, decreasing the overlap of negative and positive cases. The loss of pyloric wall stratification and echogenic muscularis propria is only seen in HPS.

Denosumab-induced bone changes in a child: a case report.

We present the case of a 9-year-old girl who developed striking bone changes following two years of denosumab therapy for giant cell lesions of the jaw.

Ultrasound for necrotizing enterocolitis: how can we optimize imaging and what are the most critical findings?

Necrotizing enterocolitis (NEC) is a common condition in the neonatal intensive care unit that continues to present challenges in terms of diagnosis and management. Traditionally NEC has been diagnosed and managed by clinical and radiographic findings, but US has shown promise in characterizing and prognosticating NEC. In this manuscript we review the abdominal US technique for NEC, the clinical significance of individual sonographic findings of NEC, and how US can be integrated in the clinical decision process for diagnosing and managing NEC. We also discuss the potential value-added role of a limited abdominal US protocol that focuses on the sonographic findings most indicative of a poor prognosis to include pneumoperitoneum, complex free fluid and focal fluid collections.

Association of new sonographic features with outcome in neonates with necrotizing enterocolitis.

BACKGROUND: We have recently noted some sonographic features in necrotizing enterocolitis that have received little or no attention in the current literature. These include thickening of the mesentery, hyperechogenicity of intraluminal intestinal contents, abnormalities of the abdominal wall, and poor definition of the intestinal wall. It has been our impression that the above four sonographic findings are generally seen in neonates with more severe necrotizing enterocolitis and may be useful in predicting outcome. OBJECTIVES: The aim of this study is, firstly, to review a large series of neonates, known to have clinical NEC, to document how frequently the above four sonographic features occur in neonates with necrotizing enterocolitis and, secondly, to determine whether they are predictive of outcome. MATERIALS AND METHODS: We retrospectively analyzed the clinical, radiographic, sonographic, and surgical findings in neonates with necrotizing enterocolitis between 2018 and 2021. The neonates were categorized into two groups based on outcome. Group A included neonates with a favorable outcome defined as successful medical treatment with no surgical intervention. Group B included neonates with an unfavorable outcome defined as failed medical treatment requiring surgery (for acute complications or late strictures) or death because of necrotizing enterocolitis. The sonographic examinations were reviewed with attention to the features of mesenteric thickening, hyperechogenicity of intraluminal intestinal contents, abnormalities of the abdominal wall, and poor definition of the intestinal wall. We then determined the association of these four findings with the two groups. RESULTS: We included 102 neonates with clinical necrotizing enterocolitis: 45 in group A and 57 in group B. Neonates in group B were born at a significantly earlier gestational age (median 25 weeks, range 22-38 weeks) and had a significantly lower birth weight (median 715.5 g, range 404-3120 g) than those in group A (median age 32 weeks, range 22-39 weeks, p = 0.003; median weight 1190 g, range 480-4500 g, p = 0.002). The four sonographic features were present in both study groups but with different frequency. More importantly, all four were statistically significantly more frequently present in neonates in group B compared to group A: (i) mesenteric thickening, A = 31 (69%), B = 52 (91%), p = 0.007; (ii) hyperechogenicity of intestinal contents, A = 16 (36%), B = 41 (72%), p = 0.0005; (iii) abnormalities of the abdominal wall, A = 11 (24%), B = 35 (61%), p = 0.0004; and (iv) poor definition of the intestinal wall, A = 7 (16%), B = 25 (44%), p = 0.005. Furthermore, the proportion of neonates with more than two signs was greater in group B compared to group A (Z test, p < 0.0001, 95% CI = 0.22-0.61). CONCLUSION: The four new sonographic features described were found to occur statistically significantly more frequently in those neonates with an unfavorable outcome (group B) than in those with a favorable outcome (group A). The presence or absence of these signs should be included in the sonographic report to convey the radiologists concern regarding the severity of the disease in every neonate, suspected or known to have necrotizing enterocolitis, as the findings may impact further medical or surgical management.

Fetal Meconium Peritonitis - Prenatal Findings and Postnatal Outcome: A Case Series, Systematic Review, and Meta-Analysis.

PURPOSE: To describe the postnatal outcome of fetal meconium peritonitis and identify prenatal predictors of neonatal surgery. METHODS: We retrospectively reviewed all fetuses with ultrasound findings suspicious for meconium peritonitis at a single center over a 10-year period. A systematic review and meta-analysis were then performed pooling our results with previous studies assessing prenatally diagnosed meconium peritonitis and postnatal outcome. Prenatal sonographic findings were analyzed to identify predictors for postnatal surgery. RESULTS: 34 cases suggestive of meconium peritonitis were diagnosed at our center. These were pooled with cases from 14 other studies yielding a total of 244 cases. Postnatal abdominal surgery was required in two thirds of case (66.5 %). The strongest predictor of neonatal surgery was meconium pseudocyst (OR [95 % CI] 6.75 [2.53-18.01]), followed by bowel dilation (OR [95 % CI] 4.17 [1.93-9.05]) and ascites (OR [95 % CI] 2.57 [1.07-5.24]). The most common cause of intestinal perforation and meconium peritonitis, found in 52.2 % of the cases, was small bowel atresia. Cystic fibrosis was diagnosed in 9.8 % of cases. Short-term neonatal outcomes were favorable, with a post-operative mortality rate of 8.1 % and a survival rate of 100 % in neonates not requiring surgery. CONCLUSION: Meconium pseudocysts, bowel dilation, and ascites are prenatal predictors of neonatal surgery in cases of meconium peritonitis. Fetuses with these findings should be delivered in centers with pediatric surgery services. Though the prognosis is favorable, cystic fibrosis complicates postnatal outcomes.

Remote ischemic conditioning in necrotizing enterocolitis: study protocol of a multi-center phase II feasibility randomized controlled trial.

PURPOSE: Remote ischemic conditioning (RIC) is a maneuver involving brief cycles of ischemia reperfusion in an individual's limb. In the early stage of experimental NEC, RIC decreased intestinal injury and prolonged survival by counteracting the derangements in intestinal microcirculation. A single-center phase I study demonstrated that the performance of RIC was safe in neonates with NEC. The aim of this phase II RCT was to evaluate the safety and feasibility of RIC, to identify challenges in recruitment, retainment, and to inform a phase III RCT to evaluate efficacy. METHODS: RIC will be performed by trained research personnel and will consist of four cycles of limb ischemia (4-min via cuff inflation) followed by reperfusion (4-min via cuff deflation), repeated on two consecutive days post randomization. The primary endpoint of this RCT is feasibility and acceptability of recruiting and randomizing neonates within 24 h from NEC diagnosis as well as masking and completing the RIC intervention. RESULTS: We created a novel international consortium for this trial and created a consensus on the diagnostic criteria for NEC and protocol for the trial. The phase II multicenter-masked feasibility RCT will be conducted at 12 centers in Canada, USA, Sweden, The Netherlands, UK, and Spain. The inclusion criteria are: gestational age < 33 weeks, weight ≥ 750 g, NEC receiving medical treatment, and diagnosis established within previous 24 h. Neonates will be randomized to RIC (intervention) or no-RIC (control) and will continue to receive standard management of NEC. We expect to recruit and randomize 40% of eligible patients in the collaborating centers (78 patients; 39/arm) in 30 months. Bayesian methods will be used to combine uninformative prior distributions with the corresponding observed proportions from this trial to determine posterior distributions for parameters of feasibility. CONCLUSIONS: The newly established NEC consortium has generated novel data on NEC diagnosis and defined the feasibility parameters for the introduction of a novel treatment in NEC. This phase II RCT will inform a future phase III RCT to evaluate the efficacy and safety of RIC in early-stage NEC.

Utility of sonography for identifying metastatic cervical adenopathy in children with differentiated thyroid carcinoma at presentation.

BACKGROUND: No study has evaluated the diagnostic accuracy of sonography for the depiction of metastatic cervical adenopathy in children with differentiated thyroid carcinoma at presentation or determined which sonographic features are most useful. OBJECTIVE: To evaluate the diagnostic accuracy of sonography for identifying metastatic cervical adenopathy in children with differentiated thyroid carcinoma at presentation and to determine the most useful sonographic features. MATERIALS AND METHODS: We evaluated cervical lymph node sonography and histology in children with proven thyroid carcinoma in a 10-year period. We excluded children in whom a preoperative sonogram was not available and those who did not have surgical resection of lymph nodes. We used histology as the gold standard. On sonography, we analyzed the size, shape, echotexture and vascularity of the lymph nodes and correlated these findings with the histology. RESULTS: We reviewed sonograms and histology of resected lymph nodes in 52 children and adolescents with proven differentiated thyroid carcinoma (33 females; ages 5-18 years, mean 13.2 years). Metastatic cervical lymph node disease was proved on histology in 33/52 (64%) of our patients at presentation. Sonographic findings correctly predicted whether the nodes were histologically involved with metastatic disease in 42/52 (81%). Sensitivity of sonography was 79%, specificity 84%, positive predictive value (PPV) 90%, negative predictive value (NPV) 70% and accuracy 81%. A significant association was seen between round shape (P=0.0002), abnormal echotexture (P≤0.0001) and vascularity (P≤0.0001), and abnormal lymph node histology. Importantly, in 11/26 (47%) patients with sonographic and histologically proven abnormal nodes, the nodes were normal in size and shape and the presence of metastatic involvement was recognized sonographically only on the basis of abnormal echogenicity and vascularity. CONCLUSION: Sonography has a high accuracy, specificity and PPV for identifying metastatic cervical lymph node involvement in children with differentiated thyroid carcinoma at presentation. Most of the abnormal lymph nodes were round in shape and had abnormal echogenicity and vascularity. Importantly, this paper emphasizes that in children, nodes with histologically proven metastases from differentiated thyroid carcinoma can be normal in size and shape. In these patients the presence of metastatic involvement might be recognized sonographically only on the basis of abnormal echogenicity and vascularity.

The role of sonography for depiction of a whirlpool sign unrelated to midgut malrotation in neonates.

BACKGROUND: The sonographic whirlpool sign of volvulus due to midgut malrotation is well recognized. However, variations of the whirlpool sign may be seen in other conditions, but this observation has received little attention in the literature. OBJECTIVE: This study presents a series of neonates with a variety of causes of congenital intestinal obstruction, all associated with a whirlpool sign (unrelated to midgut volvulus), which was correctly recognized preoperatively on sonography. We also emphasize the pivotal role of sonography in managing congenital obstruction of the intestinal tract in neonates. MATERIALS AND METHODS: This is a retrospective analysis of clinical, imaging and surgical findings in 11 neonates with congenital intestinal obstruction associated with a whirlpool sign (unrelated to midgut volvulus) that was recognized preoperatively on sonography and in whom the cause for the whirlpool was documented at surgery. RESULTS: Eleven neonates (eight male, three female) had clinical and radiographic evidence of intestinal obstruction in whom sonography depicted a whirlpool sign, which was recognized on the initial sonogram in nine and on a repeat sonogram in two. The whirlpool was located in the upper abdomen in only two, mid-abdomen in five and right lower quadrant in four. The whirlpool was only 1-2 cm in diameter. An upper gastrointestinal series in three neonates failed to depict the cause of obstruction. Contrast enema in three cases had findings suggesting the site of obstruction was in the ileum but none depicted the exact cause of the obstruction. At surgery, the whirlpool sign correlated with a segmental volvulus of the small intestine in eight neonates and with the coiled distal small intestine associated with apple-peel atresia in the other three. CONCLUSION: This study illustrates neonates in whom a whirlpool sign (unrelated to midgut volvulus) was correctly recognized on sonography before surgery. Sonography proved more useful than an upper gastrointestinal series or contrast enema in depicting the exact cause of the obstruction. Pediatric radiologists must make the effort to search throughout the entire abdomen and pelvis for a small whirlpool sign on sonography, even in the absence of midgut malrotation, in neonates with congenital intestinal obstruction. Its recognition preoperatively will facilitate a rapid diagnosis and will obviate the necessity for contrast examinations of the gastrointestinal tract, which require ionizing radiation.

The role of sonography in differentiating congenital intrinsic duodenal anomalies from midgut malrotation: emphasizing the new signs of duodenal and gastric wall thickening and hyperechogenicity.

BACKGROUND: The clinical and plain radiographic differentiation of congenital intrinsic duodenal anomalies (atresia, web, stenosis) from intestinal malrotation is not always clear. Although sonography has been documented as an important diagnostic tool in the differentiation of these two entities, its role is still not widely appreciated and it is still not universally utilized in this clinical setting. OBJECTIVE: To assess the usefulness of sonographic features of the duodenal and gastric wall in the differentiation of congenital intrinsic duodenal anomalies from midgut malrotation in a large series of neonates and to compare them with other features on abdominal radiographs, ultrasound and upper gastrointestinal series. MATERIALS AND METHODS: Using the surgical database at our tertiary pediatric hospital, we identified neonates who had surgically proven congenital intrinsic duodenal anomalies or malrotation over a period of 15 years (2000-2015). We reviewed imaging findings in both groups of neonates (blinded to the final diagnosis) with attention to the echogenicity and thickness of the wall of the duodenum and stomach, the relationship between the superior mesenteric artery and vein, the position of the third portion of the duodenum and the presence of the whirlpool sign. Findings were compared between the groups using the unpaired t-test and Fisher exact test. RESULTS: We included 107 neonates in the study, 40 with a congenital intrinsic duodenal anomaly, 49 with malrotation (36 with volvulus) and 18 with a combination of both. Duodenal and gastric wall thickening and hyperechogenicity were significantly more common in the group with a congenital intrinsic duodenal anomaly compared to those with malrotation (P<0.0001). Conversely, an abnormal relationship between the superior mesenteric artery and vein, abnormal position of the third part of the duodenum, and the whirlpool sign were significantly more common in neonates with malrotation than in those with congenital intrinsic duodenal anomalies (P<0.0001). CONCLUSION: Duodenal or gastric wall thickening, and increased wall echogenicity are helpful sonographic features in the differentiation of congenital intrinsic duodenal anomalies from malrotation. Evaluation of the duodenal and gastric wall should thus be added to the features routinely assessed on ultrasound examinations in the clinical setting of suspected duodenal obstruction in the neonate.

Meconium peritonitis: the role of postnatal radiographic and sonographic findings in predicting the need for surgery.

BACKGROUND: The role of imaging in meconium peritonitis is not limited to establishing a diagnosis; rather, it might also be helpful in determining which neonates require surgery. However, few data in the literature correlate the postnatal radiographic and sonographic findings with the need for surgery. OBJECTIVE: To compare the role of postnatal radiographic and sonographic findings in predicting the need for surgery in neonates with meconium peritonitis. MATERIALS AND METHODS: We conducted a retrospective analysis of clinical, imaging and surgical findings in all neonates with meconium peritonitis in the period 1999-2014. We divided the children into operative or non-operative groups and then correlated each group with the presence or absence of the following findings on both the radiographs and sonograms: peritoneal calcification, meconium pseudocyst, intestinal obstruction, volvulus, ascites and pneumoperitoneum. RESULTS: Thirty-seven neonates (22 males, 15 females) had meconium peritonitis in this period, of whom 23 (62%) required surgery and 14 (38%) were successfully treated non-surgically. None had an antenatal infection and three had cystic fibrosis (8%). Bowel obstruction identified on radiography (12/23, P=0.01) and sonography (9/23, P=0.04) and ascites identified with sonography (7/23, P=0.01) were associated with the need for surgical intervention. The presence of pneumoperitoneum and volvulus were also associated with surgical intervention. There was no significant statistical difference in the number of neonates with diffuse peritoneal calcification who were treated operatively or non-operatively. Four (33%) of the 12 neonates with meconium pseudocysts were successfully treated non-operatively. CONCLUSION: Imaging findings that predicted the need for surgery were intestinal obstruction, ascites, volvulus and pneumoperitoneum. Neonates with meconium pseudocysts did not require surgery if they were not associated with the described findings. The findings in our patients also indicate that those with diffuse peritoneal calcification as an isolated finding can be successfully treated non-operatively.

Utility of adult-based ultrasound malignancy risk stratifications in pediatric thyroid nodules.

BACKGROUND: Individual ultrasound (US) features have limited ability to distinguish benign from malignant thyroid nodules. Adult-based systems have been developed to integrate the sonographic features in an effort to improve diagnostic accuracy. None, however, has been validated in children, in whom the likelihood of malignancy is 2-5 times higher than adults. OBJECTIVE: To assess the performance of two adult-based sonographic (US) stratification methods for assessment of thyroid nodules in children. MATERIALS AND METHODS: This retrospective study comprised 124 children who underwent thyroid US. Three radiologists reviewed the US data using the American Thyroid Association (ATA) and the Thyroid Image Reporting and Data System (TI-RADS). Radiologists' accuracy and agreement was assessed. The reference standard was histopathology/cytology or 2-year follow-up of clinical outcome for nonoperative cases. RESULTS: We assessed 71 benign and 52 malignant nodules and excluded 1 nodule. Using the ATA pattern descriptions, 80% of malignant nodules were classified as "high" 36/52 (69%) or "intermediate" 6/52 (11%) likelihood of malignancy. A total of 20/71 (28%) benign nodules were also classified within these two categories. Using the TI-RADS, malignant nodules were classified as 2, 3, 4a, 4b, 4c and 5, with rate of malignancy of 0%, 0%, 7/52 (13.5%), 7/52 (13.5%), 32/52 (61.5%) and 6/52 (11.5%), respectively. Benign nodules were also classified in the 4a (26/71; 36.6%), 4b (17/71; 24%), 4c (14/71; 19.7%) and 5 (1/71; 1.4%) categories. The positive and negative predictive values were 68.0% and 87.5% for ATA, and 71.7% and 80.0% for TI-RADS. CONCLUSION: We validated the use of ATA and TI-RADS methods in children and showed that they have test characteristics similar to those in adults, although neither is independently sufficient to discriminate nodules' likelihood of malignancy.

Value of abdominal ultrasound in management of necrotizing enterocolitis: a systematic review and meta-analysis.

PURPOSE: Necrotizing enterocolitis (NEC) remains a life-threatening disease among infants in the NICU. Early diagnosis and careful monitoring are essential to improve outcomes. Abdominal ultrasound (AUS) seems a promising addition to current diagnostic modalities, but its clinical utility is uncertain. The aim of this study was to identify AUS features associated with definite NEC (i.e. Bell stage ≥ II), failed medical treatment, surgery, and death. METHODS: Embase, MEDLINE, Web of Science and CINAHL databases were searched for studies that addressed any NEC-related AUS feature in relation to any of the four outcomes. After critical appraisal of relevant study methods, meta-analyses were conducted using a random-effect model. RESULTS: 15 out of 1215 studies were included. All AUS features had sensitivities below 70% and specificities largely above 80% for diagnosing definite NEC; several AUS features were significantly associated with failed medical treatment and surgery. Substantial heterogeneity, poor reporting quality and uncertain risk of bias were found. CONCLUSIONS: While clear associations of AUS features with failed medical treatment exist and AUS may detect definite NEC, substantial heterogeneity, poor reporting quality and an uncertain risk of bias impair the use of AUS for clinical decision making. A prospective, well-designed validation study is needed.

Sonographic Bands of Hypoechogenicity in the Spleen in Children: Zebra Spleen.

OBJECTIVE: Zebra spleen is the normal pattern of splenic enhancement during the arterial phase of CT and MRI and is attributed to different flow rates. The purpose of this study was to describe the appearance and occurrence of bands of hypoechogenicity in the spleen on unenhanced sonograms of children with no splenic abnormalities. MATERIALS AND METHODS: We reviewed 100 abdominal ultrasound studies to evaluate the ultrasound characteristics of the spleen. Demographic data were collected for all patients. RESULTS: Homogeneous echogenicity of the spleen was found in 92 children. Heterogeneous echogenicity was present in eight. Three of the eight had discrete macronodules due to known splenic disease. The other five had bands of hypoechogenicity. These five had no known splenic disease, but one had mild splenomegaly of unknown cause. CONCLUSION: The pattern of hypoechoic bands occurred in 5% of our series. This pattern cannot be explained simply by different flow rates and probably reflects different structural components of the parenchyma. At ultrasound this pattern should be considered a normal finding that may simulate a splenic mass.

Effect of Supplemental Donor Human Milk Compared With Preterm Formula on Neurodevelopment of Very Low-Birth-Weight Infants at 18 Months: A Randomized Clinical Trial.

Importance: For many very low-birth-weight (VLBW) infants, there is insufficient mother's milk, and a supplement of pasteurized donor human milk or preterm formula is required. Awareness of the benefits of mother's milk has led to an increase in use of donor milk, despite limited data evaluating its efficacy. Objective: To determine if nutrient-enriched donor milk compared with formula, as a supplement to mother's milk, reduces neonatal morbidity, supports growth, and improves neurodevelopment in VLBW infants. Design, Setting, and Participants: In this pragmatic, double-blind, randomized trial, VLBW infants were recruited from 4 neonatal units in Ontario, Canada, within 96 hours of birth between October 2010 and December 2012. Follow-up was completed in July 2015. Interventions: Infants were fed either donor milk or formula for 90 days or to discharge when mother's milk was unavailable. Main Outcomes and Measures: The primary outcome was the cognitive composite score on the Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III) at 18 months' corrected age (standardized mean, 100 [SD, 15]; minimal clinically important difference, 5 points). Secondary outcomes included Bayley-III language and motor composite scores, growth, and a dichotomous mortality and morbidity index. Results: Of 840 eligible infants, 363 (43.2%) were randomized (181 to donor milk and 182 to preterm formula); of survivors, 299 (92%) had neurodevelopment assessed. Mean birth weight and gestational age of infants was 996 (SD, 272) g and 27.7 (2.6) weeks, respectively, and 195 (53.7%) were male. No statistically significant differences in mean Bayley-III cognitive composite score (adjusted scores, 92.9 in donor milk group vs 94.5 in formula group; fully adjusted mean difference, -2.0 [95% CI, -5.8 to 1.8]), language composite score (adjusted scores, 87.3 in donor milk group vs 90.3 in formula group; fully adjusted mean difference, -3.1 [95% CI, -7.5 to 1.3]), or motor composite score (adjusted scores, 91.8 in donor milk group vs 94.0 in formula group; fully adjusted mean difference, -3.7 [95% CI, -7.4 to 0.09]) were observed between groups. There was no statistically significant difference in infants positive for the mortality and morbidity index (43% in donor milk group, 40% in formula group) or changes in growth z scores. Conclusions and Relevance: Among VLBW infants, use of supplemental donor milk compared with formula did not improve neurodevelopment at 18 months' corrected age. If donor milk is used in settings with high provision of mother's milk, this outcome should not be considered a treatment goal. Trial Registration: isrctn.org Identifier: ISRCTN35317141.

In vivo ultrasound assessment of gastric emptying in newborn mice.

OBJECTIVES: The aim of the present study was to develop an ultrasonographic approach to comparatively assess gastric emptying in newborn wild-type and guanosine triphosphate cyclohydrolase knockout hph-1 mice, because we previously reported gastroparesis early in life in this strain. METHODS: Stomach transverse, anteroposterior, and longitudinal ultrasonographic measurements were obtained with a 40-MHz transducer in pups immediately after maternal separation and 4 hours later. A conventional equation was used and the predicted values validated by obtaining postmortem gastric content volume measurements. Wild-type and hph-1 mice gastric emptying rates were comparatively evaluated at 1 to 3 and 5 to 8 days of age, respectively. RESULTS: The ultrasound equation closely predicted the newborn stomach content volumes with a correlation coefficient (R) of 0.93 and 0.81 (P < 0.01) for measurements obtained on full stomach and after 4 hours of fasting, respectively. In wild-type mice, gastric emptying was age dependent and associated with a greater residual volume at 1 to 3 days (65% ± 7%), as compared with 5- to 8-day-old pups (33% ± 4%; P  < 0.01), after fasting. In contrast, an equal duration of fasting resulted in a significantly greater residual gastric content volume in 5- to 8-day-old hph-1 mice (68%  ± 7%; P < 0.01), as compared with same-age wild-type mice. CONCLUSIONS: Ultrasonography offers a sensitive and accurate estimate of gastric content volume in newborn mice. In wild-type newborn mice, gastric emptying rate is age dependent and significantly reduced in the immediate postnatal period. The newborn hph-1 mice have a significantly higher gastric residual volume, as compared with wild-type same-age animals.

Neurosonography: in pursuit of an optimized examination.

This article emphasizes technical factors that are helpful for optimizing sonographic examinations of the brain in preterm and term neonates. It also reviews existing data regarding the accuracy of neurosonographic examinations relative to MR. Many neurosonographic signs are subtle and can be easily overlooked, which could lead to delayed diagnosis or misdiagnosis. Therefore meticulous attention to sonographic technique is required to maximize the diagnostic utility of this modality. Although MR images of the brain often depict abnormalities more clearly than sonography, neurosonography continues to be an exceptionally valuable tool for evaluation of the neonatal brain, even in full-term neonates. Furthermore, its accuracy is greater, even in the latter age group, than many older publications suggest. Prospective studies using state-of-the-art equipment comparing findings on sonography and MR are needed to better understand how the accuracy of these modalities changes with refinements in equipment and to help us better understand the role of neurosonography relative to MR.

The value of repeat scintigraphy in patients with a high clinical suspicion for Meckel diverticulum after a negative or equivocal first Meckel scan.

BACKGROUND: Technetium (99m)Tc-pertechnetate is the most common and accurate noninvasive method of preoperative investigation for Meckel diverticulum. Despite introducing various methods to increase the sensitivity of the study, there are many case reports of false-negative Meckel scans. A repeat scan is sometimes requested in patients with a high suspicion for Meckel diverticulum and negative or equivocal first Meckel scan. OBJECTIVES: The purpose of this retrospective study is to evaluate the value of repeat scintigraphy for these patients. MATERIALS AND METHODS: Seven hundred fifty-three Meckel scans were recorded retrospectively. In 33 cases (22 male and 11 female; mean age: 6.8 years), the Meckel scintigraphy was repeated either due to a high clinical suspicion of Meckel diverticulum and a negative study (n = 21) or due to equivocal findings in the first scan (n = 12). The study was interpreted as positive if an abnormal focal activity was identified in the abdomen and pelvis during the procedure. The results were correlated with pathology and clinical symptoms. RESULTS: Seven out of 12 (58%) equivocal studies were positive on the second study. Six of them were proven to be positive at operation (confirmed by pathology) while one of them was negative on laparoscopy. From 21 negative first scans with a high suspicion for Meckel diverticulum, three (14%) were positive on the second study. All three were proven to be Meckel diverticulum on pathology. CONCLUSION: Repeat Meckel scans in patients with equivocal findings on the first study or a negative result with a high clinical suspicion for a Meckel diverticulum are useful especially in cases in which the first study had been done without appropriate preparation.

The role of ultrasound in the follow-up of children with differentiated thyroid cancer.

BACKGROUND: Thyroid cancer is the most common endocrine malignancy with relatively good prognosis in children. However, unlike adults, children usually present with more advanced disease and have a higher local recurrence and distant metastases. Thus surveillance for recurrence is a major goal of long-term follow-up. OBJECTIVE: This retrospective study evaluates the diagnostic value of ultrasound (US) imaging in the post-therapy surveillance of children with differentiated thyroid cancer. MATERIALS AND METHODS: We reviewed the charts of 54 children (40 girls; mean age 14.3 ± 3.6 years) with differentiated thyroid cancer treated with total or near-total thyroidectomy. Forty children (29 girls and 11 boys) who had routine follow-up US examinations (112 studies) were included for the evaluation of US accuracy in the follow-up of pediatric differentiated thyroid cancer. Histopathology, stimulated thyroglobulin determination, post-therapy whole-body iodine scan and clinical follow-up were used as the standards of reference. RESULTS: Mean period of follow-up was 34 months. The frequency of recurrence was 42% (17/40). Seventeen percent of the children had lung metastases either at presentation or on follow-up. In all cases of lung metastases, stimulated thyroglobulin level was greater than 10 ng/ml. The sensitivity was 85.7%, specificity 89.4%, negative predictive value 94.4% and positive predictive value 75% for US in detecting loco-regional recurrence in follow-up studies of pediatric differentiated thyroid cancer. In 17.3% (18/104) of studies, the results of stimulated thyroglobulin and US were discordant. CONCLUSION: US showed very good sensitivity and specificity and a high negative predictive value for evaluation of loco-regional involvement in follow-up of pediatric differentiated thyroid cancer. Diagnostic whole-body iodine scan is indicated when serum anti-thyroglobulin Ab is high, or in cases of discordant findings between US and stimulated thyroglobulin levels, or when stimulated thyroglobulin levels are >10 ng/ml (to evaluate for lung metastasis).

Prospective evaluation of the impact of sonography on the management and surgical intervention of neonates with necrotizing enterocolitis.

BACKGROUND/AIM: Established indications for surgery in necrotizing enterocolitis (NEC) are pneumoperitoneum and failure to improve or clinical deterioration with medical treatment alone. It has been proposed that infants with intestinal necrosis may benefit from surgery in the absence of one of these indications yet the diagnosis of definitive intestinal necrosis is challenging. Recent data suggest that abdominal ultrasound (US) examination focused on the gastrointestinal tract and the peritoneal cavity may be of utility in this regard. The aim of this study was to evaluate the ability of abdominal US to detect intestinal necrosis in infants with radiographically confirmed NEC. METHODS: Twenty-six consecutive infants with Bell stage II or III NEC were prospectively included in the study between September 2013 and July 2014. Infants with a pre-existing indication for surgery were excluded. At least one abdominal US examination was performed in each patient using a standardized previously described method. Surgery was performed at the discretion of the attending surgeon based on clinical and imaging findings. Clinical, radiographic, US, and intra-operative data were recorded to allow comparison between US findings, surgical findings and outcome. RESULTS: US demonstrated signs of intestinal necrosis in 5 of the 26 patients. All of these five had laparotomy. Intestinal necrosis requiring resection was confirmed in four and the other was found to have NEC but no necrosis was identified. In 21 patients US did not suggest intestinal necrosis. Of these, only one had surgery in whom NEC but no necrosis was identified. The remaining 20 responded to medical treatment for NEC and were assumed not to have had intestinal necrosis based on improvement without surgical intervention. The sensitivity, specificity, positive predictive value and negative predictive values of US for the detection of bowel necrosis were calculated as 100, 95.4, 80.0, and 100%, respectively. CONCLUSION: Our prospective findings suggest that abdominal US can identify those infants with NEC who may need surgery by detecting bowel necrosis (prior to the development of perforation or medical deterioration) with high sensitivity and specificity. Early surgical intervention in the clinical pathway of NEC may lead to improved outcomes.