Predictors of Failure in Ultrasound-Guided Hydrostatic Reduction of Intussusception in Children: Retrospective Analysis in a Specialized Center in Ethiopia

Purpose

To identify factors predicting the failure of ultrasound-guided hydrostatic reduction of intussusception in children.

Patients and Methods

The medical records of 174 children who underwent ultrasound-guided hydrostatic reduction of intussusception over four years were reviewed at Tikur Anbessa Specialized Hospital. Patient's demography, clinical data, and sonography findings (type of intussusception, length of intussusception, presence of lead point, trapped fluid, lymph node, and free peritoneal fluid) were entered into SPSS 25 (IBM) and analyzed using logistic regression.

Results

The overall success rate of ultrasound-guided hydrostatic reduction was 81.6%. The sex, presence of abdominal cramps, vomiting, diarrhea, trapped lymph nodes on ultrasound, or history of upper respiratory tract infection had no association with hydrostatic reducibility. Currant jelly stool (OR 0.128; 95% CI, 0.27-0.616; P=0.01), Ileo-ileo colic intussusception (OR 0.055; 95% CI, 0.005-0.597; P=0.017), pathologic lead point (OR 0.66; 95% CI, 0.01-0.447; P=0.005) and abdominal distention (OR 0.209; 95% CI, 0.044-0.998; P=0.048) showed significant association with failed hydrostatic reduction.

Conclusion

The presence of currant jelly stool, ileo-ileo colic type intussusception, pathologic lead point, and abdominal distention are the most important predictors for failed ultrasound ultrasound-guided reduction intussusception in children.

Technical and Interpretive Pitfalls in Pediatric Musculoskeletal Ultrasound

The use of musculoskeletal (MSK) ultrasound (US) in pediatric rheumatology has expanded rapidly with various diagnostic and therapeutic indications. Unlike magnetic resonance imaging (MRI), US allows real-time dynamic assessment, evaluation of multiple joints in a single session and comparison with contralateral limb. However, a long learning curve and lack of experience with MSK US in pediatric patients still precludes its routine use at many imaging centers. It is prudent for pediatric radiologists to be aware of normal US appearances of the growing MSK structures to avoid their misinterpretation as pathology. The normal MSK US findings in children which can be confused with pathology and create diagnostic difficulty can arise due to variable states of maturation of bones, cartilage and tendons, complex anatomical locations, accessory structures, and artifacts. Herein, we describe the various technical and interpretive challenges encountered with MSK US in pediatric patients.

A Technique to Reduce the Early Recurrence of Intussusception in Ultrasound-Guided Hydrostatic Reduction

OBJECTIVES

Ultrasound-guided saline enema is highly successful in treating pediatric intussusception; however, early recurrence-within 48 hours-is possible. This study aimed to explore effective methods of reducing early recurrence.

METHODS

This study included patients aged 0 to 14 years diagnosed with ileocolic intussusception with a symptom duration of <48 hours from January 2019 to March 2021. The patients were divided into control and intervention groups. All patients received successful treatment with ultrasound-guided saline enema; however, in patients treated before January 4, 2020 (control group), the intestinal fluid was drained immediately, and in patients treated after January 4, 2020 (intervention group), the intestinal fluid was drained after 15 minutes of intestinal pressure maintenance. Early recurrence rates of the groups were compared.

RESULTS

Ileocolic intussusception was treated successfully by ultrasound-guided saline enema in 231 patients (116, control group;115, intervention group). The early recurrence rate in the intervention group (10%; 95% CI: 4.9-16.5) was numerically lower than that in the control group (19%; 95% CI: 12.3-27.3). No significant difference was observed in the number of recurrences per person between the groups (P = .448). Patients without early recurrence were older (P = .004) and received enemas of a shorter duration (P < .001) and lower pressure (P < .001) than patients without early recurrence.

CONCLUSIONS

Maintaining reduction pressure for 15 minutes after a successful ultrasound-guided saline enema may reduce the early recurrence of intussusception. A randomized controlled trial is needed because the intervention and control cohorts were most probably incomparable (due to the COVID-19 pandemic).

Gallbladder polyp in children - a rare finding during ultrasound examination

Gallbladder polyps are a relatively rare finding in children. The increased use of high-resolution ultrasound in childhood allows to detect gallbladder lesions in young patients. A precise diagnosis can be established using different imaging series. Abdominal contrast-enhanced ultrasound examination provides the most accurate imaging information about the nature and size of the lesion. This is important for further decisions regarding patient referral for cholecystectomy. The object of this study was to present a case of gallbladder polyp diagnosed and followed up by contrast-enhanced ultrasound.

Cervical Extension of the Normal Thymus in Children and Adolescents: Sonographic Features and Prevalence

OBJECTIVE

This study aims to confirm the prevalence of incidental cervical extension of normal thymus in children and adolescents undergoing neck ultrasound and describe the ultrasound appearance to minimize future misdiagnosis.

MATERIALS AND METHODS

This retrospective study was conducted in a single institution. Thyroid and lower neck ultrasound images of the consecutive pediatric subjects between January 1, 2011 and September 30, 2017 were independently reviewed by 2 radiologists for the presence of cervical thymus. When identified on sonographic images, cervical thymus was described on the basis of echogenicity, location, and shape.

RESULTS

In 278 consecutive cases, the 2 reviewers identified 105 (37.8%) and 103 (37.1%) cases respectively as having sonographically visible tissue in the expected location of cervical extension of the thymus. The internal echotexture was variable with 38.1% of cases being hypoechoic, 37.1% mixed, and 24.8% hyperechoic. Cervical extension of the thymus was most commonly (65.0%) to the left of the trachea or (30.9%) bilateral/anterior to the trachea; isolated right paratracheal thymus was uncommon. Thymic shape was variable: quadrilateral (30.9%), oval (29.9%), triangular (25.8%), and other (13.4%). The logistic regression model including age, gender, and BMI z-scores showed that, when controlled for sex and BMI z-scores, younger age was a predictor for the presence of cervical thymic extension (p < .001).

CONCLUSION

Cervical thymic extension is sonographically visible as a soft tissue mass of variable appearance in about a third of children and adolescents undergoing neck ultrasonography with decreasing prevalence with age. Sonographically visible cervical thymic tissue is more common in younger patients.

Ultrasound Versus Traditional Palpation to Guide Radial Artery Cannulation in Critically Ill Children: A Randomized Trial

OBJECTIVES

To identify success rates for radial artery cannulation in a pediatric critical care unit using either palpation or ultrasound guidance to cannulate the radial artery.

METHODS

A prospective randomized comparative study of critically ill children who required invasive monitoring in a tertiary referral center was conducted. All patients were randomized by a stratified block of 4 to either ultrasound-guided or traditional palpation radial artery cannulation. The primary outcomes were the first attempt and total success rates.

RESULTS

Eighty-four children were enrolled, with 43 randomized to the palpation technique and 41 to the ultrasound-guided technique. Demographic data between the groups were not significantly different. The total success and first attempt rates for the ultrasound-guided group were significantly higher than those for the palpation group (success ratio, 2.03; 95% confidence interval, 1.13-3.64; P = .018; and success ratio, 4.18; 95% confidence interval, 1.57-11.14; P = .004, respectively). The median time to success for the ultrasound-guided group was significantly shorter than that for the palpation group (3.3 versus 10.4 minutes; P < .001). Cannulation complications were lower in the ultrasound-guided group than the palpation group (12.5% versus 53.3%; P < .001).

CONCLUSIONS

The ultrasound-guided technique could improve the success rate and allow for faster cannulation of radial artery catheterization in critically ill children.

Role of Point Shear Wave Elastography in the Determination of the Severity of Fibrosis in Pediatric Liver Diseases With Pathologic Correlations

OBJECTIVES

Our aims in this study were as follows: (1) to determine the cutoff value that can distinguish between advanced liver fibrosis and normal liver tissue for two different elastographic techniques; (2) to determine the cutoff value that can distinguish mild liver fibrosis from normal liver tissue for the techniques; and (3) to assess tissue stiffness in nonalcoholic fatty liver disease (NAFLD).

METHODS

Seventy-five patients assessed for liver biopsy on the same day were evaluated by point shear wave elastography. Thirty-one healthy children and 11 children with NAFLD were also evaluated. A 9L4 transducer with Virtual Touch quantification (VTQ) and Virtual Touch imaging and quantification (VTIQ) modes (Siemens Medical Solutions, Mountain View, CA) was used for quantification.

RESULTS

The shear wave speed of the patients with NAFLD was higher than that of the control group. The only predictive factor for VTQ and VTIQ was the histologic fibrosis score (model-adjusted R²  = 0.56 for VTQ and 0.75 for VTIQ). Shear wave speed cutoffs were 1.67 m/s for VTQ and 1.56 m/s for VTIQ in detecting fibrosis or inflammation and 2.09 m/s for VTQ and 2.17 m/s for VTIQ in discriminating children with low and high histologic liver fibrosis scores.

CONCLUSIONS

The VTQ and VTIQ values reveal high-grade histopathologic fibrosis and have high success rates when distinguishing high- from low-grade fibrosis. However, they have limited success rates when differentiating low-grade fibrosis from normal liver tissue.

A Convex Hull-Based New Metric for Quantification of Bladder Wall Irregularity in Pediatric Patients With Congenital Anomalies of the Kidney and Urinary Tract

OBJECTIVES

Early identification and quantification of bladder damage in pediatric patients with congenital anomalies of the kidney and urinary tract (CAKUT) is crucial to guiding effective treatment and may affect the eventual clinical outcome, including progression of renal disease. We have developed a novel approach based on the convex hull to calculate bladder wall trabecularity in pediatric patients with CAKUT. The objective of this study was to test whether our approach can accurately predict bladder wall irregularity.

METHODS

Twenty pediatric patients, half with renal compromise and CAKUT and half with normal renal function, were evaluated. We applied the convex hull approach to calculate T, a metric proposed to reflect the degree of trabeculation/bladder wall irregularity, in this set of patients.

RESULTS

The average T value was roughly 3 times higher for diseased than healthy patients (0.14 [95% confidence interval, 0.10-0.17] versus 0.05 [95% confidence interval, 0.03-0.07] for normal bladders). This disparity was statistically significant (P < .01).

CONCLUSIONS

We have demonstrated that a convex hull-based procedure can measure bladder wall irregularity. Because bladder damage is a reversible precursor to irreversible renal parenchymal damage, applying such a measure to at-risk pediatric patients can help guide prompt interventions to avert disease progression.

Diagnostic Accuracy of Sonography for Detection of a Fistula on the Birth Day in Neonates With an Imperforate Anus: Comparison of Diagnostic Performance Between Suprapubic and Perineal Approaches

OBJECTIVES

To evaluate the diagnostic accuracy of sonography for detection of an internal fistula on the birth day in neonates with an imperforate anus and to compare the diagnostic performance between the suprapubic and perineal approaches.

METHODS

We included 46 neonates with an imperforate anus (29 low type and 17 intermediate/high type) who underwent sonography by both the suprapubic and perineal approaches on the birth day. Thirty-nine neonates had internal fistulas, and 12 did not, as surgically proven. Two blinded radiologists evaluated the suprapubic and perineal sonograms for the presence of the internal fistula in consensus. A final diagnosis of the internal fistula was determined on the basis of the findings of both approaches. A receiver operating characteristic analysis was used to compare the diagnostic performance for detection of an internal fistula between the suprapubic and perineal approaches.

RESULTS

The sensitivity, specificity, and accuracy of the final diagnosis based on the findings of suprapubic, perineal, and both approaches were 52.9%, 79.4%, and 79.4%; 75.5%, 75.5%, and 75.5%; and 58.7%, 78.3%, and 78.3%, respectively. The diagnostic performance of the perineal approach was significantly better than that of the suprapubic approach (P < .0001).

CONCLUSIONS

The diagnostic accuracy of sonography for detection of an internal fistula on the birth day exceeded 75% in neonates with an imperforate anus, and sonography on the birth day is feasible. The perineal approach had superior diagnostic performance over the suprapubic approach. Thus, when evaluating an internal fistula by sonography, we recommend using the perineal approach in addition to the suprapubic approach.

Sonography for an Imperforate Anus: Approach, Timing of the Examination, and Evaluation of the Type of Imperforate Anus and Associated Anomalies

This systematic review outlines the role of sonography in an imperforate anus. The diagnostic performance for type of imperforate anus is superior on the day after birth than that on the day of birth by using the pouch-perineum distance. Three approaches can be used (suprapubic, infracoccygeal, and perineal). The pouch-perineum distance, fistula location, and relationship between the puborectalis muscle and distal rectal pouch are useful for classifying the type of imperforate anus. However, the pouch-perineum distance measured has an overlap between the low and high/intermediate types of imperforate anus. Sonography can be useful for some of the associated anomalies and helpful for surgeons in some cases.

Comparison of Diagnostic Accuracy for the Low-Type Imperforate Anus Between Prone Cross-Table Radiography and Sonography

OBJECTIVES

To compare the diagnostic accuracy for the low-type imperforate anus between prone cross-table radiography and sonography.

METHODS

We included 20 neonates with imperforate anus: 13 with a surgically proven low type and 7 with an intermediate or high type. The distance between the distal rectal pouch and the perineum (pouch-perineum distance) was measured by both sonography and prone cross-table radiography. A previously established pouch-perineum distance of 10 mm was used as the cutoff for diagnosis of a low-type imperforate anus. The fistula location was also determined with sonography. We then compared the diagnostic accuracy of the imaging methods for a low-type imperforate anus using the cutoff value of the pouch-perineum distance alone and both the cutoff value of the pouch-perineum distance and fistula location. The McNemar test was used for statistical analysis.

RESULTS

With the use of only the pouch-perineum distance, the diagnostic accuracy for the low-type imperforate anus based on sonographic measurements was comparable with the accuracy achieved by prone cross-table radiographic measurements (60.0% [12 of 20] versus 45.0% [9 of 20]; P = .625). With the use of the pouch-perineum distance and fistula location, the diagnostic accuracy of sonography was significantly better than the accuracy of prone cross-table radiography (90.0% [18 of 20] versus 45% [9 of 20]; P = .012).

CONCLUSIONS

The diagnostic accuracy of sonography for the low-type imperforate anus based on both the pouch-perineum distance and fistula location is better than that of prone cross-table radiography. If the pouch-perineum distance on prone cross-table radiography is greater than 10 mm, a sonographic examination to determine the fistula location could be recommended.

Hemodynamics as Measured With Color Doppler Sonography in Early-Stage Obesity-Related Nephropathy in Children

OBJECTIVES

We retrospectively studied hemodynamic changes in the interlobar artery to assess the clinical value of color Doppler sonography for detecting preclinical obesity-related nephropathy.

METHODS

Color Doppler renal sonography was performed in 52 children with obesity-related nephropathy and 51 control children with simple obesity. The interlobar artery resistive index (RI) was measured and compared with clinical data and laboratory indicators.

RESULTS

The left RI (mean ± SD, 0.65 ± 0.05 versus 0.60 ± 0.08; t = 3.85), right RI (0.64 ± 0.03 versus 0.59 ± 0.02; t = 10.00), and mean RI (0.64 ± 0.05 versus 0.59 ± 0.06; t = 5.00) revealed large statistically significant increases in the obesity-related nephropathy group (all P < .01). In the obesity-related nephropathy group, a positive correlation was found between the mean RI and 24-hour urine trace albumin (r = 0.47; P < .01), triglycerides (r = 0.98; P < .01), and body mass index (r = 0.28; P < .05). The 24-hour urine trace albumin and triglycerides were higher in the obesity-related nephropathy group than the control group (P < .05). In the control group, a mild positive correlation was also found between the mean RI and body mass index (r = 0.24; P < .05).

CONCLUSIONS

Color Doppler sonography successfully indicated renal hemodynamic changes and has diagnostic value for early-stage obesity-related nephropathy.

Excessive Bright Echoes Sign for Hypertrophic Pyloric Stenosis Suggest the Diagnosis: Gastric Pneumatosis and Portal Venous Gas in Infants Suggest HPS

We describe a new finding, the "excessive bright echoes" sign, for the diagnosis of hypertrophic pyloric stenosis (HPS). Portal venous gas and gastric wall pneumatosis were noted in 4 vomiting infants proven to have HPS. Portal venous gas can be concerning for ischemic bowel. Gastric wall pneumatosis can be seen in association with necrotizing enterocolitis and has been associated with increased gastric pressure from severe, usually proximal, bowel obstruction. Our HPS cases had prominent bright punctate echoes on sonography of the liver, portal vein lumen, and gastric wall. Knowledge of this excessive bright echoes sign suggests the need for sonography of the antropyloric area. One should consider HPS as a differential diagnostic possibility when the combination of bright echoes within the liver parenchyma, consistent with portal venous gas, and bright echoes in the gastric wall, consistent with gastric pneumatosis, are seen.

Changes in the Distance Between the Distal Rectal Pouch and Perineum From the Birth Day to the Next Day in Neonates With an Imperforate Anus

OBJECTIVES

To evaluate changes in the distance between the distal rectal pouch and the perineum (pouch-perineum distance) from the birth day to the next day and to determine which day is better for diagnosis of a low-type imperforate anus in neonates.

METHODS

We reviewed medical records at our hospital from May 2003 to August 2015 and identified 9 neonates with a radiographically and surgically proven low-type imperforate anus and 9 with high/intermediate types of imperforate anus who had undergone sonography on both the birth day and the next day before the first surgical treatment. The sonograms were reviewed to measure the pouch-perineum distance at both examinations. The Wilcoxon signed rank sum test and a receiver operating characteristic curve analysis were used for the statistical analyses.

RESULTS

The pouch-perineum distance on the next day (mean ± SD, 9.37 ± 4.89 mm; range, 2.1-20.9 mm) was significantly shorter than on the birth day (15.75 ± 6.67 mm; range, 8.1-37.2 mm; P = .001). The receiver operating characteristic analysis showed significantly better diagnostic performance (P < .001) of the pouch-perineum distance on the next day (area under the curve, 0.864) versus the birth day (0.420) for the low-type imperforate anus.

CONCLUSIONS

The pouch-perineum distance was shorter on the next day than on the birth day, and the diagnostic performance of the pouch-perineum distance on the next day was significantly superior to that on the birth day for the diagnosis of a low-type imperforate anus. We recommend sonography on the next day in neonates with an imperforate anus when possible.

Limited Abdominal Sonography for Evaluation of Children With Right Lower Quadrant Pain

OBJECTIVES

To determine whether a complete abdominal sonographic examination is necessary in the evaluation of children with right lower quadrant pain that is suspicious for appendicitis in the emergency department and whether performing a limited, more-focused study would miss clinically important disease.

METHODS

With Institutional Review Board approval, a retrospective study was performed of 704 patients, from ages 5-19 years, presenting to the emergency department with right lower quadrant pain that was suspicious for appendicitis who underwent a complete abdominal sonographic examination. Data were extracted from the complete abdominal sonographic examination to see whether abnormalities were noted in the pancreas, spleen, and left kidney. Patients' medical charts were reviewed to see whether any positive findings in these organs were clinically important.

RESULTS

Of the 65 studies with a finding that would have been missed with a limited study, only 6 were found to be clinically important. Of those, 5 were managed medically and 1 surgically. The chance of missing a potentially important finding using a limited study with our group of patients was 65 of 704 patients (9.2%), with a 95% confidence interval of 7.2% to 11.7%. The chance of missing an abnormality that was clinically important was 6 of 704 patients (0.85%), with a 95% confidence interval of 0.35% to 1.94%.

CONCLUSIONS

In children older than 5 years with abdominal pain that is suspicious for appendicitis, performing only a limited abdominal sonographic examination that excludes the pancreas, left kidney, and spleen will yield a miss rate for clinically important disease that is acceptably low to justify the savings of examination time.

Prenatal Anogenital Distance Is Shorter in Fetuses With Hypospadias

OBJECTIVES

Recent research provides evidence that anogenital distance may serve as a novel metric to assess reproductive potential in men. In children, a shorter anogenital distance was linked with cryptorchidism, hypospadias, and micropenis. Scarce data exist in the literature regarding anogenital distance measurement in the fetus. The aim of our study was to assess whether intrauterine measurement of fetal anogenital distance could assist in the differential diagnosis of male genital anomalies.

METHODS

Anogenital distance was prospectively measured in all cases referred for suspected isolated abnormal male genitalia. Final diagnoses, confirmed by a pediatric urologist, were compared with anogenital distance prenatal measurements.

RESULTS

Fifty-two cases were referred for evaluation because of suspected male external genital malformation during a 12-month period. Cases with normal-appearing genitalia, associated major malformations, and early severe fetal growth restriction were excluded from the study. Postnatal examination revealed 14 cases of hypospadias in varying severity and 8 cases of a buried penis. All fetuses with hypospadias had an anogenital distance measurement below the fifth percentile. Statistical analysis revealed a significant difference between the normal mean anogenital distance for gestational age versus those with hypospadias (mean ± SD, 16.90 ± 4.08 and 11.68 ± 3.31 mm, respectively; P = .001). No significant difference was found between the normal mean anogenital distance for gestational age versus those with a buried penis (18.85 ± 2.76 and 19.46 ± 3.41 mm; P = .700).

CONCLUSIONS

Fetuses with hypospadias have a statistically significant shorter anogenital distance compared with the general population. Therefore, anogenital distance may serve as a complementary objective sonographic parameter in the prenatal assessment and counseling of male external genital anomalies.

Role of Sonography for Evaluation of Gastrointestinal Foreign Bodies

Foreign body ingestion is frequently encountered in children. The locations of the foreign bodies and the period during which they have been present in the thorax and abdomen are important for determining the method and timing of treatment. Although plain radiography and computed tomography are primarily used for assessment of foreign bodies, sonography without radiation is also useful for diagnosis of foreign bodies. This report describes 5 cases of foreign bodies in the digestive tract and the usefulness of sonography for real-time evaluation of foreign bodies with high spatial resolution. Physicians can use sonography along with radiography and computed tomography in cases involving foreign bodies.

Resistive Index Variability in Anterior Cerebral Artery Measurements During Daily Transcranial Duplex Sonography: A Predictor of Cerebrovascular Complications in Infants Undergoing Extracorporeal Membrane Oxygenation?

OBJECTIVES

The purpose of this study was to determine the value of resistive index (RI) variability in predicting cerebrovascular complications during extracorporeal membrane oxygenation (ECMO).

METHODS

This retrospective study included 36 infants treated by ECMO. The RI was measured on daily transfontanellar duplex sonography, obtained first without fontanel compression and then after gentle compression with the transducer. The age at ECMO cannulation, sex, gestational age at birth, method of delivery, indication, and type and duration of ECMO were recorded.

RESULTS

There was a statistically significant difference in RI variability in infants who developed cerebrovascular complications as opposed to those who did not (P = .002). Resistive index variability of 10% or greater on any day was associated with an increased risk for cerebrovascular complications (P = .0482; χ² = 3.9). Variability in the first 5 days was significantly higher than on following days (P < .0001). The age at ECMO cannulation showed a significant difference, with mean ± SD values of 1.1 ± 0.9 days in the complications group and 2.7 ± 2.2 days in the no-complications group (P = .043).

CONCLUSIONS

Resistive index variability of 10% or greater on any day had a statistically significant risk of cerebrovascular complication development. Extracorporeal membrane oxygenation cannulation at younger than 3 days conferred an increased risk of cerebrovascular complications.

Doppler Sonography of Blood Flow Velocity in the Vertebral Arteries of Preterm and Term Neonates

OBJECTIVES

This study aimed to evaluate normal blood flow in the vertebral arteries and the basilar artery of preterm and term neonates by Doppler sonography.

METHODS

Blood flow in both vertebral arteries and the basilar artery was examined in 102 neonates between the biological ages of 28 and 41 weeks. Fifty-one boys and 51 girls underwent Doppler sonography. Measurements were usually undertaken at 6 days old. Systolic and diastolic flow velocities, including the resistive index, were measured and analyzed, taking into consideration biological age, weight, and sex. Anatomic aberrations of the vertebral arteries were recorded.

RESULTS

Mean blood flow values ± SD in the basilar artery were 35.2 ± 7.4 cm/s (systolic velocity) and 10.9 ± 3.5 cm/s (diastolic velocity). Mean blood flow values in the right vertebral artery were 26.8 ± 9.3 cm/s (systolic velocity) and 8.0 ± 3.7 cm/s (diastolic velocity). Mean blood flow values in the left vertebral artery were 28.6 ± 8.3 cm/s (systolic velocity) and 8.7 ± 3.3 cm/s (diastolic velocity). Systolic and diastolic blood flow in both vertebral arteries was significantly higher from 38 to 41 weeks compared with 28 to 32 and 33 to 37 weeks (P < .05). Regression analysis of systolic and diastolic blood flow velocities in the vertebral arteries versus biological age yielded significant results (P < .05).

CONCLUSIONS

Sonography is an excellent tool for examining blood flow in the basilar and vertebral arteries of premature and term neonates. Mean systolic and diastolic blood flow velocities in the vertebral arteries increase significantly with age.

Echocardiographic Parameters and Outcomes in Primary Fetal Cardiomyopathy

OBJECTIVES

Primary fetal cardiomyopathy is a rare entity, with a poor prognosis. We sought to describe its echocardiographic characteristics and outcomes.

METHODS

We performed a 12-year retrospective review of fetuses with primary cardiomyopathy.

RESULTS

Of more than 6000 fetuses evaluated, 25 met criteria for primary cardiomyopathy, and 18 had sufficient echocardiographic and pregnancy outcome data for inclusion. At echocardiography, the median gestational age was 29.6 weeks (range, 21.0-36.4 weeks); median cardiovascular profile score was 6 (range, 1-9); median right ventricular Tei index was 0.52 (range, 0.32-0.94); and median left ventricular Tei index was 0.40 (range, 0.15-0.88). Two had fetal demise, and 16 survived to delivery. The median cardiovascular profile score in those with fetal demise was 3.0 and in those who survived to delivery was 6.5 (range, 3-9; P = .14). The median right ventricular Tei index in those with fetal demise was 0.39 and in those surviving to delivery was 0.53 (range, 0.38-0.94; P = .49). The median left ventricular Tei index in those with fetal demise was 0.29 and in those surviving to delivery was 0.42 (range, 0.15-0.88; P = .50). Sixty-day survival was available in 11 of 16 fetuses. In addition to the 2 with fetal demise, 4 had postnatal demise, and 5 were alive at a median follow-up of 39 months. Hydrops (P = .01), skin edema (P = .01), and mild or greater mitral regurgitation (P = .02) were associated with fetal or postnatal demise, with a trend toward an association between moderate or greater tricuspid regurgitation (P = .07) and fetal or postnatal demise.

CONCLUSIONS

Hydrops and atrioventricular valvar regurgitation are ominous signs in primary fetal cardiomyopathy. Although other commonly used methods for assessing cardiovascular performance may help in diagnosing primary cardiomyopathy, these data suggest limited predictive value.

Thrombosis of Inferior Vena Cava Diagnosed Using Point-of-Care Ultrasound After Pediatric Near-Syncope

BACKGROUND

Venous thromboembolism (VTE) is extremely rare but under recognized in the pediatric population. Although the literature on the use of ultrasound to detect VTEs in adults is plentiful, little has been documented on its use in the pediatric population.

CASE REPORT

We present a case of a healthy 16-year-old female who presented to our emergency department with 3 months of dyspnea on exertion and one episode of near-syncope. Point-of-care cardiac ultrasound identified an inferior vena cava thrombosis. Subsequent computed tomography angiography diagnosed concurrent bilateral pulmonary emboli (PE). The patient's identical twin sister presented with similar symptoms shortly thereafter and was also diagnosed with VTE and bilateral PE. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: This case demonstrates an instance of VTE and pulmonary embolism in twin adolescent girls. Physical examination findings, electrocardiogram, chest x-ray study, and several previous evaluations did not reveal the diagnosis. Point of care ultrasound was used to correctly diagnosis VTE and for heightened concern for a pulmonary embolism.

Expected Sonographic Appearance of the Spleen in Children and Young Adults With Sickle Cell Disease: An Update

OBJECTIVES

To update the imaging literature regarding spleen appearances in young patients with sickle cell disease (SCD).

METHODS

We conducted a retrospective study and included 112 patients age 0 to 21 years with SCD who had at least 1 abdominal sonogram at our institution between 1999 and 2011. Radiologic findings were compared between risk groups by χ(2) analysis. Findings were correlated with other imaging modalities when available.

RESULTS

In our cohort, 35.7% of patients had autosplenectomy, and 8.0% had undergone surgical splenectomy. Only 5.0% of individuals age 0 to 5 years had autosplenectomy. In those who had not undergone surgical splenectomy or autosplenectomy, 76.2% had echogenic spleens, heterogeneous-appearing spleens, or both, and patients with the homozygous sickle cell anemia (HbSS) genotype were more likely to have an abnormal spleen echo texture. Patients treated with transfusions had echogenic spleens and had a higher frequency of splenic regeneration nodules. Most patients (80%) with splenomegaly did not require surgical splenectomy after 5.7 years of follow-up.

CONCLUSIONS

Twenty years ago, children with HbSS SCD were expected to have autosplenectomy by age 5 years. There have been changes in the radiologic appearance of the spleen in patients with SDC, likely due to improved supportive care and the use of acute and chronic transfusion therapy. We found that autosplenectomy is rare by age 5 years, and during childhood and adolescence, the spleen typically appears echogenic, heterogeneous, or both, depending on disease severity.

Intrarenal Reflux: Diagnosis at Contrast-Enhanced Voiding Urosonography

Vesicoureteral reflux (VUR) is a childhood condition that is usually diagnosed by fluoroscopic voiding cystourethrography (VCUG). Intrarenal reflux (IRR) of infected urine is believed to play an important role in the pathogenesis of reflux-associated pyelonephritis and subsequent parenchymal scarring and is traditionally depicted by fluoroscopic VCUG. This case series describes the phenomenon of IRR occurring in association with VUR in 4 children as depicted by contrast-enhanced voiding urosonography. The ability of contrast-enhanced voiding urosonography to show IRR when it occurs in conjunction with VUR compares favorably to that of fluoroscopic VCUG.

Utility of Shear Wave Elastography for Differentiating Biliary Atresia From Infantile Hepatitis Syndrome

OBJECTIVES

The purpose of this study was to investigate the potential utility of shear wave elastography (SWE) for diagnosis of biliary atresia and for differentiating biliary atresia from infantile hepatitis syndrome by measuring liver stiffness.

METHODS

Thirty-eight patients with biliary atresia and 17 patients with infantile hepatitis syndrome were included, along with 31 healthy control infants. The 3 groups underwent SWE. The hepatic tissue of each patient with biliary atresia had been surgically biopsied. Statistical analyses for mean values of the 3 groups were performed. Optimum cutoff values using SWE for differentiation between the biliary atresia and control groups were calculated by a receiver operating characteristic (ROC) analysis.

RESULTS

The mean SWE values ± SD for the 3 groups were as follows: biliary atresia group, 20.46 ± 10.19 kPa; infantile hepatitis syndrome group, 6.29 ± 0.99 kPa; and control group, 6.41 ± 1.08 kPa. The mean SWE value for the biliary atresia group was higher than the values for the control and infantile hepatitis syndrome groups (P < .01). The mean SWE values between the control and infantile hepatitis syndrome groups were not statistically different. The ROC analysis showed a cutoff value of 8.68 kPa for differentiation between the biliary atresia and control groups. The area under the ROC curve was 0.997, with sensitivity of 97.4%, specificity of 100%, a positive predictive value of 100%, and a negative predictive value of 96.9%. Correlation analysis suggested a positive correlation between SWE values and age for patients with biliary atresia, with a Pearson correlation coefficient of 0.463 (P < .05).

CONCLUSIONS

The significant increase in liver SWE values in neonates and infants with biliary atresia supports their application for differentiating biliary atresia from infantile hepatitis syndrome.

Sonography for Complete Evaluation of Neonatal Intensive Care Unit Central Support Devices: A Pilot Study

OBJECTIVES

Neonates in the neonatal intensive care unit often require considerable support with endotracheal tubes, umbilical arterial and venous catheters, and peripherally inserted central venous catheters. Support device evaluation with radiography exposes neonates to ionizing radiation. This study evaluated the effectiveness of sonographic localization for endotracheal tubes, umbilical arterial and venous catheters, and peripherally inserted central venous catheters.

METHODS

This blinded prospective Institutional Review Board-approved, Health Insurance Portability and Accountability Act-compliant study with informed consent compared sonography to radiography for endotracheal tube, umbilical arterial and venous catheter, and peripherally inserted central venous catheter localization. Participants were consecutively recruited NICU patients of any weight, gestation, and chronologic age who had an endotracheal tube, umbilical arterial catheter, umbilical venous catheter, or peripherally inserted central venous catheter placed or adjusted and had subsequent radiographic confirmation within 24 hours. Sonographic evaluation was obtained as soon as possible, without prior review of the radiograph, and results were compared.

RESULTS

Thirty sonographic studies were performed in 25 patients (14 male and 11 female), for a total of 50 lines and tubes: 18 umbilical venous catheters, 12 umbilical arterial catheters, 11 peripherally inserted central venous catheters, and 9 endotracheal tubes. Forty-nine support devices (98%) were visualized with sonography, all concordant with radiography. Forty-four were correctly positioned, and 6 were malpositioned. Sonography identified the location of umbilical venous catheters in all 18 cases (100%), umbilical arterial catheters in all 12 (100%), peripherally inserted central venous catheters in 10 (91%), and endotracheal tubes in 9 (100%).

CONCLUSIONS

The effectiveness of sonography was excellent for evaluation of umbilical arterial and venous catheters, endotracheal tubes, and peripherally inserted central venous catheters. These results support the goal of further point-of-care training and accreditation to use sonography as a primary modality for complete evaluation of NICU support devices.

Sonographic Detection of Accessory Adrenal Tissue in Neonates

OBJECTIVES

The purpose of this study was to describe the incidence and appearance of accessory adrenal tissue in neonates, as diagnosed by high-resolution sonography, and increase the awareness of this entity.

METHODS

We examined the adrenal glands in 153 neonates referred for renal and urinary tract sonography at our institution between January 2014 and January 2015. All kidneys and adrenal glands, except for ectopic kidneys, were scanned with the neonate prone and a linear array transducer with frequency of 11 or 14 MHz.

RESULTS

In 9 neonates (5.9%), sonography showed a round, well-defined structure adjacent to the adrenal gland with a hyperechoic center and hypoechoic periphery, similar to the echogenicity of the normal adrenal medulla and cortex, respectively. The largest diameter of the structure measured 2.9 to 4.5 mm. On follow-up studies, which were available for 7 neonates, the structure was not evident, and the suprarenal area was normal.

CONCLUSIONS

Accessory adrenal tissue can be identified in the suprarenal area in neonates with high-resolution sonography. Radiologists and sonographers caring for neonates should be aware of this finding and not confuse it with disease.

Sonography of the Pediatric Chest

Traditionally, pediatric chest diseases are evaluated with chest radiography. Due to advancements in technology, the use of sonography has broadened. It has now become an established radiation-free imaging tool that may supplement plain-film findings and, in certain cases, the first-line modality for evaluation of the pediatric chest. This pictorial essay will demonstrate the diagnostic potential of sonography, review a spectrum of pediatric chest conditions, and discuss their imaging features and clinical importance.

Sonographic Analysis of Changes in Skull Shape After Cranial Molding Helmet Therapy in Infants With Deformational Plagiocephaly

OBJECTIVES

-The purpose of this study was to investigate the changes in skull shape on sonography after cranial molding helmet therapy in infants with deformational plagiocephaly.

METHODS

-Twenty-six infants who were treated with cranial molding helmet therapy were recruited. Caliper and sonographic measurements were performed. The lateral length of the affected and unaffected sides of the skull and cranial vault asymmetry index were measured with calipers. The occipital angle, defined as the angle between lines projected along the lambdoid sutures of the skull, was calculated by sonography. The occipital angle difference and occipital angle ratio were also measured. All caliper and sonographic measurements were performed in each infant twice before and twice after treatment.

RESULTS

-The study group included 12 male and 14 female infants with a mean age ± SD of 6.2 ± 3.5 months. The mean treatment duration was 6.0 ± 2.5 months. The difference in lateral length before and after helmet therapy was significantly greater on the affected skull than the unaffected skull (16.7 ± 12.7 versus 9.0 ± 13.4 mm; P < .01). The difference in the occipital angle before and after helmet therapy was significantly greater on the affected skull than the unaffected skull (-5.7° ± 7.3° versus 4.2° ± 7.9°; P < .01). The cranial vault asymmetry index and occipital angle ratio were significantly reduced after helmet therapy (cranial vault asymmetry index, 9.3% ± 2.3% versus 3.5% ± 3.0%; occipital angle ratio, 1.07 ± 0.05 versus 1.01 ± 0.01; P < .05).

CONCLUSIONS

-These results suggest that occipital angle measurements using sonography, combined with cephalometry, could provide a better understanding of the therapeutic effects of cranial molding helmet therapy in infants with deformational plagiocephaly.

Spatiotemporal Image Correlation and Volumetric Impedance Indices in the Neonatal Brain: Proof of Concept and Preliminary Reproducibility

OBJECTIVES

Changes in tissue perfusion can be critically important in the vulnerable neonate, but they are very difficult to assess at the bedside. Spatiotemporal image correlation (STIC) sonography is an exciting concept that allows assessment of blood flow by rearranging and merging multiple 2-dimensional color images to create serial 3-dimensional images showing regional blood flow throughout the cardiac cycle. Variations in tissue blood flow may reflect tissue impedance and perfusion. The aim of this study was to demonstrate that it is possible to use STIC images to evaluate tissue impedance in the neonatal brain.

METHODS

Spatiotemporal image correlation data sets were acquired by cranial sonography in 19 neonates. Offline data analysis was performed by using virtual organ computer-aided analysis. With the use of STIC images from different phases of the cardiac cycle, impedance indices were calculated, based on maximum (systolic), minimum (diastolic), and mean virtual organ computer-aided analysis values, in the same way that resistive indices are calculated in 2-dimensional sonography.

RESULTS

Volumetric indices for tissue impedance were obtained for all neonates. Intraclass correlation coefficients (95% confidence intervals) for volumetric impedance indices were as follows: systolic/diastolic ratio, 0.793 (0.615-0.906); pulsatility index, 0.790 (0.609-0.905); and resistive index, 0.783 (0.598-0.901). Interclass correlation coefficients for image processing and analysis were as follows: systolic/diastolic ratio, 0.868 (0.692-0.947); pulsatility index, 0.904 (0.772-0.962); and resistive index, 0.914 (0.794-0.966).

CONCLUSIONS

This study shows that STIC data sets can be used to calculate volumetric impedance indices in the neonatal brain. Preliminary assessment shows that this technique appears reliable and allows evaluation of regional tissue impedance in the neonate.

Sonography of Abdominal Pain in Children: Appendicitis and Its Common Mimics

Abdominal pain is very common in the pediatric population (<18 years of age). Sonography is a safe modality that can often differentiate the frequently encountered causes of abdominal pain in children. This pictorial essay will discuss the sonographic findings of acute appendicitis, including the imaging appearance of a perforated appendicitis. It will also present the sonographic features of the relatively common mimics of appendicitis, such as mesenteric adenitis/gastroenteritis, intussusception, Meckel diverticulum, and ovarian torsion.

Off-Label Use of Ultrasound Contrast Agents for Intravenous Applications in Children: Analysis of the Existing Literature

OBJECTIVES

The purpose of this study was to collect and analyze the published data related to intravenous (IV) use of ultrasound (US) contrast agents in children.

METHODS

We searched the literature to collect all of the published studies reporting the IV administration of a second-generation US contrast agent in children.

RESULTS

We analyzed 9 case series and 5 case reports, as well as 5 individual cases, of pediatric contrast-enhanced US use reported in a study group that also included adults. We found that 502 children underwent contrast-enhanced US examinations (mean age, 9.7 years; range, 1 day-18 years). Most patients (89%) were injected with the sulfur hexafluoride contrast agent SonoVue (Bracco SpA, Milan, Italy). The mean dose used was 1.5 mL (range, 0.1-9.6 mL). Only 10 patients (2%) had adverse reactions related to the contrast agent administration: 1 life-threatening anaphylactic shock and 9 mild transitory adverse effects. We additionally found 38 papers in which the study groups included at least 1 child; thus, we obtained a total of 540 reported cases of off-label use of IV US contrast agents in children. The most frequent target organ was the liver, and most indications were related to space-occupying lesion characterization and abdominal evaluations after blunt trauma. Some studies also evaluated the diagnostic performance of contrast-enhanced US in different clinical scenarios and found very good accuracy. Concordance between contrast-enhanced US imaging and the respective reference-standard imaging methods ranged between 83% and 100% in different studies.

CONCLUSIONS

Our results support the idea that the IV use of US contrast agents in children is safe, feasible, diagnostically robust, and effective.

Evaluation of Parotid Glands With Real-time Ultrasound Elastography in Children

OBJECTIVES

The aim of this study was to determine the strain index for parotid glands in children by using ultrasound elastography.

METHODS

In this prospective study, apparently healthy children were referred from the ear-nose-throat clinic to the radiology clinic for elastographic examinations. Conventional sonographic and elastographic examinations of the parotid glands were performed. A linear 5-12-MHz transducer was used to obtain the images.

RESULTS

A total of 54 children were enrolled in this prospective study. The normal mean strain index value ± SD for the parotid glands was 1.24 ± 0.67 (range, 0.29-1.39) regardless of sex. The mean age of girls was 7.42 ± 2.94 years (range, 3-14 years), and the age of boys was 8.50 ± 3.46 years (range, 4-16 years). The strain index values for the parotid glands in boys was 1.25 ± 0.76, and in girls it was 1.22 ± 0.55. There was no statistically significant difference in the strain index values between girls and boys (P= .986). There was no correlation between the strain index and age (r = 0.026) or body mass index (r = 0.066).

CONCLUSIONS

This study determined the mean strain index values for apparently healthy children. Such information can serve as a baseline from which pathologic parotid diseases can be diagnosed with ultrasound elastography in combination with other sonographic criteria.

Superficial Echogenic Lesions Detected on Neonatal Cranial Sonography: Possible Indicators of Severe Birth Injury

OBJECTIVES

The purpose of this study was to evaluate the characteristics and importance of superficial echogenic lesions around cranial sutures on neonatal cranial sonography.

METHODS

We retrospectively reviewed the clinical records and neuroimaging studies of 40 neonates who had superficial echogenic lesions around sutures on neonatal cranial sonography. Magnetic resonance imaging (n = 18) and computed tomography (n = 2) were performed within 2 weeks after sonography. We correlated sonographic findings with computed tomographic and magnetic resonance imaging findings and analyzed them. We also evaluated the associated lesions, neurologic signs, and follow-up changes.

RESULTS

Sonographically, the superficial echogenic lesions involved both sulci and perisulcal parenchyma in 39 neonates and were located in the frontal and parietal areas around the sagittal suture in 38 neonates. Magnetic resonance imaging revealed a pattern of hypoxic ischemic encephalopathy in 9 neonates, birth trauma in 3 neonates, a mixed pattern of hypoxic ischemic encephalopathy and trauma in 3 neonates, nonspecific single infarctions in 2 neonates, and lack of a defined lesion in 1 neonate. The associated lesions were subdural hemorrhage (n = 12), epidural hematoma (n = 4), germinal matrix hemorrhage (n = 3), intraventricular hemorrhage (n = 2), and periventricular leukomalacia (n = 1). All epidural hematomas were associated with scalp hematoma, and 2 patients had skull fractures. One neonate with epidural hematoma associated with a hypoxic ischemic encephalopathy pattern showed mild spasticity in both ankles until 16 months.

CONCLUSIONS

Superficial echogenic lesions detected around cranial sutures on neonatal sonography may be an indicator of more serious intracranial lesions such as more extensive hypoxic ischemic encephalopathy and intracranial hematomas, including epidural hematoma.

Point-of-Care Ultrasound Findings Associated With Langerhans Cell Histiocytosis in the Pediatric Emergency Department

Langerhans cell histiocytosis is a rare disease characterized by clonal proliferation of Langerhans-type cells, causing local or systemic effects. One of the most affected sites in children is the skull. We describe 2 cases of children presenting to the pediatric emergency department with symptoms isolated to the scalp and the point-of-care focused skull ultrasound findings, which assisted in the diagnosis of Langerhans cell histiocytosis in both cases.

Polycystic Thyroid Disease in Pediatric Patients: An Uncommon Cause of Hypothyroidism

Polycystic thyroid disease has been described as a rare cause of hypothyroidism. This uncommon entity has been reported in adults within areas with high iodine intake. Sonographic findings of multiple small thin-walled simple thyroid cysts in the context of hypothyroidism without thyroid autoantibodies are highly suggestive of this diagnosis. To our knowledge, we report the first 2 cases of polycystic thyroid disease in pediatric patients in Europe.

B-Lines on Pediatric Lung Sonography: Comparison With Computed Tomography

OBJECTIVES

Sonographic artifacts known as B-lines can been used to estimate alterations of lung parenchyma. Multiple B-lines on sonography are seen in congestive heart disease, interstitial lung disease, respiratory infections, and neonates. The aim of this study was to compare the amount of B-lines on sonography to the extent of parenchymal changes on computed tomography (CT) in children.

METHODS

Lung sonography was performed on 60 patients aged 18 years and younger referred for chest CT at our institution. B-lines were counted from 5 anterolateral intercostal spaces bilaterally. The CT findings were documented and graded as absent, minimal, partial, or complete.

RESULTS

The number of B-lines on sonography increased consistently with the growing extent of parenchymal changes on CT. The differences in the B-line counts between the patients grouped according to the extent of parenchymal changes on CT were statistically significant except between patients with minimal and no changes (P < .01 Kruskal-Wallis and Tukey tests).

CONCLUSIONS

The number of B-lines on sonography correlates with the extent of parenchymal changes on CT. Various parenchymal changes were seen in patients with B-lines on sonography. B-lines were more frequently seen in patients with no changes on CT when imaged during general anesthesia.

Sonographic Evaluation of Diaphragmatic Excursion and Thickness in Healthy Infants and Children

OBJECTIVES

M-mode sonography is a noninvasive method for detection of diaphragmatic excursion and thickness. A few studies have assessed diaphragmatic kinetics in children with diaphragmatic paresis and paralysis, but to our knowledge, no data about normal values in pediatrics are available. The aims of this study were to determine reference values for diaphragmatic excursion and thickness, as evaluated by sonography in healthy infants and children, and identify correlations between them and anthropometric measurements, age, and sex.

METHODS

A total of 400 healthy participants aged between 1 month and 16 years, divided into 4 equal groups (group 1, 1 month-2 years; group 2, 2-6 years; group 3, 6-12 years); and group 4, 12-16 years) were studied. M-mode sonography was used to measure the excursion and thickness of the right and left hemidiaphragms (using the liver and spleen as acoustic windows, respectively).

RESULTS

Reference values for diaphragmatic excursion and thickness were determined in different age groups of healthy infants and children. There were no significant differences with respect to sex. Significant positive correlations were found between excursion of the right hemidiaphragm and body weight in all age groups (r = 0.52, 0.25, 0.27. and 0.20; P < .001, .013, .011, and .047 for groups 1-4, respectively). We plotted percentile curves for right diaphragmatic excursion against body weight.

CONCLUSIONS

This study provides reference values for diaphragmatic excursion and thickness in healthy infants and children. Percentile curves for right diaphragmatic excursion plotted against body weight were plotted.

Transcranial Doppler Sonography in Pediatric Neurocritical Care: A Review of Clinical Applications and Case Illustrations in the Pediatric Intensive Care Unit

Transcranial Doppler sonography is a noninvasive, real-time physiologic monitor that can detect altered cerebral hemodynamics during catastrophic brain injury. Recent data suggest that transcranial Doppler sonography may provide important information about cerebrovascular hemodynamics in children with traumatic brain injury, intracranial hypertension, vasospasm, stroke, cerebrovascular disorders, central nervous system infections, and brain death. Information derived from transcranial Doppler sonography in these disorders may elucidate underlying pathophysiologic characteristics, predict outcomes, monitor responses to treatment, and prompt a change in management. We review emerging applications for transcranial Doppler sonography in the pediatric intensive care unit with case illustrations from our own experience.

Optimal Filum Terminale Thickness Cutoff Value on Sonography for Lipoma Screening in Young Children

OBJECTIVES

The purpose of this study was to evaluate the normal thickness of the filum terminale on sonography and suggest an optimal cutoff value for filum terminale lipoma screening in young children.

METHODS

We retrospectively reviewed lumbosacral sonograms and magnetic resonance images from children younger than 36 months that were obtained between January 2013 and June 2014. The filum terminale thickness on sonography and the presence of fat in the filum terminale on magnetic resonance imaging were evaluated.

RESULTS

From 111 children (mean age ± SD, 3.6 ± 3.0 months), 49 did not have abnormal lesions (normal group), and 62 had fat infiltration in the filum terminale (lipoma group). The filum terminale was thicker in the lipoma group than the normal group (1.5 ± 0.5 versus 0.9 ± 0.2 mm; P < .001). Filum terminale thickness also showed significance in a multivariable analysis with sex and age (odds ratio per 0.1-mm unit, 2.754; P < .001) and in propensity score matching for age (P < .001). The optimal cutoff value for filum terminale lipoma screening was 1.1 mm, with 94% sensitivity and 86% specificity.

CONCLUSIONS

The conventional cutoff value of 2 mm for a thickened filum terminale on sonography can be too thick. We suggest an optimal cutoff value of 1.1 mm for lipoma screening in young children.

Quantitative Sonographic Texture Analysis in Preterm Neonates With White Matter Injury: Correlation of Texture Features With White Matter Injury Severity

OBJECTIVES

To analyze the texture features on cranial sonography in preterm neonates with white matter injury quantitatively and to correlate these features with magnetic resonance imaging (MRI).

METHODS

The study included 33 preterm neonates treated in our neonatal intensive care unit who underwent serial cranial sonography and brain MRI near term. Patients were subdivided into 3 groups according to the presence and severity of white matter injury as revealed by MRI: normal (group 1; n = 20), mild (group 2; n = 5), and severe (group 3; n = 8). The periventricular echogenicity on sonography was evaluated quantitatively with second-order gray-level statistics (gray-level co-occurrence matrix [GLCM] method). Four GLCM texture features representing homogeneity were extracted in 12 directions: (1) angular second moment (ASM), (2) inverse differential moment (IDM), (3) contrast, and (4) entropy.

RESULTS

Thirty of 48 features showed a statistically significant difference between groups 1 and 3 (ASM in 9 directions, IDM in 6 directions, contrast in 3 directions, and entropy in all 12 directions). There were no significant differences observed between groups 1 and 2 or groups 2 and 3. The mean contrast and entropy values were generally lower in group 1 than group 3, whereas the mean ASM and IDM values were higher in group 1.

CONCLUSIONS

Severe white matter injury could be identified by using GLCM texture analysis, whereas mild white matter injury observed on MRI could not be evaluated by GLCM analysis. Quantitative texture analysis using the GLCM may serve as a complementary tool for quantitative assessment of periventricular echogenicity.

Prepubertal Testicular Teratomas and Epidermoid Cysts: Comparison of Clinical and Sonographic Features

OBJECTIVES

To evaluate clinical and sonographic features of testicular teratomas and epidermoid cysts in children and to assess differential points of immature teratomas from benign counterparts.

METHODS

We retrospectively reviewed testicular teratomas and epidermoid cysts in children. Age at surgery, α-fetoprotein (AFP) level, and sonographic findings, including components (mainly cystic, mainly solid, or mixed), presence of calcification, and size, were reviewed.

RESULTS

Nineteen cases were included, with 10 mature teratomas, 3 immature teratomas, and 6 epidermoid cysts. On sonography, most of the teratomas (n = 9) had mixed components, with 2 mainly cystic and 2 mainly solid lesions. The 2 mainly cystic teratomas underwent follow-up sonography and showed component changes to mainly solid. Compared to epidermoid cysts, teratomas were larger (P = .029) with less cystic components (P = .046). All 3 immature teratomas showed mixed components with calcification. In differentiating immature from benign teratomas, immature teratomas were larger (P= .047) in younger children (P= .008) with higher AFP levels (P= .023). The optimal cutoff values for diagnosing immature teratomas were 8 months of age, 23 ng/mL in AFP level, and 2.5 cm in size, with 100% sensitivity and 89.5% accuracy rates. However, sonographic features, including tumor components and presence of calcification, were not helpful for differentiating immature teratomas.

CONCLUSIONS

Testicular masses in children younger than 8 months with AFP levels higher than 23 ng/mL and size larger than 2.5 cm need to be considered for orchiectomy rather than testis-sparing tumorectomy because of the increased frequency of immature teratomas versus mature teratomas or epidermoid cysts.

Neonatal Lung Sonography: Interobserver Agreement Between Physician Interpreters With Varying Levels of Experience

OBJECTIVES

To assess the reliability of lung sonography in neonates between physician interpreters with different degrees of experience.

METHODS

We retrospectively reviewed lung sonograms from neonates admitted to a neonatal intensive care unit with respiratory distress in the first 24 hours of life. The first scans were selected; only patients with available video clips documenting both hemithoraxes were included. The clips were independently examined by 4 different experienced observers blinded to clinical data. The interpreting physicians made a codified sonographic diagnosis, and the Cohen κ coefficient was used to measure the reliability between a proven experienced main interpreter and expert (κ1), intermediate (κ2), and beginner (κ3) control interpreters. We also calculated the specific agreement on respiratory distress syndrome and transient tachypnea of the neonate.

RESULTS

Four hundred sixty-five clips were taken from 114 neonates examined over a 16-month period. The patients' median gestational age (range) was 34 weeks (25-41 weeks), and the median birth weight (range) was 2085 g (608-4134 g). Eighty-eight percent of examinations were performed within 24 hours after birth. The overall κ coefficients (95% confidence intervals) were κ1 = 0.94 (0.88-1.00); κ2 = 0.72 (0.61-0.83); and κ3 = 0.81 (0.71-0.90). For respiratory distress syndrome, κ1 = 0.94 (0.87-1.00); κ2 = 0.90 (0.81-0.99); and κ3 = 0.87 (0.78-0.97). For transient tachypnea of the neonate, κ1 = 0.95 (0.89-1.00); κ2 = 0.76 (0.64-0.88); and κ3 = 0.81 (0.70-0.91).

CONCLUSIONS

In neonates with early respiratory distress, lung sonography has high interobserver agreement even between interpreters with varying levels of experience.

The baseline diameter of the inferior vena cava measured by sonography increases with age in normovolemic children

OBJECTIVES

To evaluate normative sonographic measurements of the inferior vena cava (IVC) diameter in healthy pediatric patients.

METHODS

We performed a prospective observational study of a convenience sample of healthy patients between the ages of 0 and 22 years presenting to a pediatric emergency department. Exclusion criteria included abnormal vital signs, pregnancy, or illnesses thought to influence volume status. During quiet respiration, the maximum and minimum IVC diameters were measured in the sagittal plane distal to the hepatic vein-IVC junction. As second measurements, the maximum diameters of the IVC and aorta were measured in the transverse plane distal to the insertion of the left renal vein into the IVC.

RESULTS

From February 2013 through April 2014, 63 children (51% female; mean age, 11 years) were enrolled. There were 20 children in each age group of 2 to 7, 7 to 12, and 12 to 22 years. The correlations between IVC and aortic diameters as a function of age were calculated using the Spearman rank correlation coefficient. The correlation coefficients were all statistically significant (P < .001): sagittal maximum IVC diameter (0.81), sagittal minimum IVC diameter (0.79), transverse maximum IVC diameter (0.79), and transverse maximum aortic diameter (0.81).

CONCLUSIONS

This pilot study of sonographic measurements of the IVC diameter in normovolemic children suggests a statistically significant positive correlation between age and IVC diameter. Future studies should focus on multicenter enrollment, children in the youngest age group, and the development of normative growth curves for the IVC by age, sex, and body mass index.

Sonographic evaluation of hydronephrosis in the pediatric population: is well-tempered sonography necessary?

OBJECTIVES

Standardized protocols exist for diuretic renography. There are no specific guidelines regarding hydration before renal sonography. This study assessed the importance of the hydration status by sonographic measurements of the anteroposterior diameter and its effect on Society for Fetal Urology (SFU) hydronephrosis grading.

METHODS

Children aged 6 weeks to 16 years (mean age, 22 months) with unilateral SFU grade 3 or 4 hydronephrosis requiring diuretic renal scintigraphy were recruited to undergo prehydration and posthydration renal sonography. Hydrated diuretic renal scintigraphy, or "well-tempered" renography, was then performed. Renal sonograms were reviewed by a blinded pediatric radiologist and pediatric urologist. Two-sided statistical tests assessed whether SFU grades and the anteroposterior diameter changed significantly after hydration.

RESULTS

Among 67 kidneys, the pediatric urologist (L.P.M.) and pediatric radiologist (V.J.R.) reported no SFU grade change in 45 (67%) and 52 (78%) kidneys after hydration. In kidneys that changed, the posthydration grade was more likely to be higher. This difference was statistically significant (14 of 22 and 13 of 15 differences were higher grades after hydration for L.P.M. and V.J.R., respectively; P= .06; P= .007). Most kidneys that changed with hydration differed by only 1 SFU grade. Differences greater than 1 grade were seen in 5 control kidneys, which increased from SFU grade 0 to 2. The mean anteroposterior diameter increased significantly between prehydration and posthydration sonography for both hydronephrotic kidneys (1.46 versus 1.72 cm; P< .001) and control kidneys (0.22 versus 0.39 cm; P= .019), but did not correlate with increased SFU grades.

CONCLUSIONS

Hydration does have a substantial effect on the anteroposterior diameter, but it does not correlate with a substantial effect on the SFU grade; therefore, well-tempered sonography seems unnecessary.

Feasibility and reliability of quantifying passive muscle stiffness in young children by using shear wave ultrasound elastography

OBJECTIVES

The purpose of this study was to investigate the feasibility and reliability of passive muscle stiffness measurements in children by shear wave ultrasound elastography.

METHODS

We conducted a prospective cross-sectional study quantifying the passive stiffness of bilateral lateral gastrocnemius muscles during passive stretching in 20 typically developing children (age range, 2.0-12.6 years). Data collected included passive stiffness of the lateral gastrocnemius muscle (shear modulus in kilopascals) at 4 positions of progressive passive foot dorsiflexion, demographic characteristics of the participants, and comparison of demographic characteristics with the shear modulus.

RESULTS

Passive stiffness increased with increasing stretching (mean [SD] range of stiffness, 7.1 [2.0] to 36.2 [22.0] kPa). For all 4 foot positions, no significant difference was found between right and left legs (range, P = .42 to P = .98) or between the sexes (range, P = .28 to P > .99). No correlation of passive muscle stiffness with age, body mass index, or ankle range of motion was found. The reliability of measurements was good to excellent (mean [95% confidence interval] range of reliability, 0.67 [0.44-0.83] to 0.80 [0.63-0.90]).

CONCLUSIONS

Measurements of passive stiffness of the lateral gastrocnemius muscle are feasible and reliable in children as young as 2 years. Because this study found no significant difference between sex and the side tested in this age group, future studies involving children of this age range may not need to be stratified on the basis of these parameters. Defining normal passive muscle stiffness in children is critical for identifying and understanding the implications of abnormal passive muscle stiffness in children with neuromuscular disorders.

Scrotal swelling in the neonate

Discovery of scrotal swelling in a neonate can be a source of anxiety for parents, clinicians, and sonologists alike. This pictorial essay provides a focused review of commonly encountered scrotal masses and mimics specific to the neonatal setting. Although malignancy is a concern, it is very uncommon, as most neonatal scrotal masses are benign. Key discriminating features and management options are highlighted to improve the radiologist's ability to diagnose neonatal scrotal conditions and guide treatment decisions. Neonatal scrotal processes ranging from common to uncommon will be discussed.

Nonsurgical management of childhood intussusception: retrospective comparison between sonographic and fluoroscopic guidance

OBJECTIVES

The purpose of this study was to compare the effectiveness of sonography and fluoroscopy in guiding intussusception reduction and evaluate possible complications for each procedure.

METHODS

A retrospective analysis was performed by reviewing 31 cases of intussusception diagnosed and managed between January 2009 and January 2014 at the University of California, Davis Children's Hospital, after obtaining approval from the Institutional Review Board. To eliminate other confounding factors related to technique and experience, only cases performed by 2 pediatric radiologists who exclusively used either fluoroscopy or sonography were compared.

RESULTS

Fourteen patients (age range, 6-35 months) were treated by sonographic guidance using saline, and another 17 patients (age range, 2-57 months) were treated by fluoroscopy using either air or a water-soluble contrast agent. All 14 patients (100%) who underwent sonographically guided reduction were successfully treated without complications. Fourteen of the 17 patients (82%) who underwent fluoroscopic guidance had successful reductions. One complication of perforation was documented.

CONCLUSIONS

Sonography and fluoroscopy are equally effective in the nonsurgical management of childhood intussusception. The absence of ionizing radiation and better visualization of possible pathologic lead points makes sonography the ideal method.

Risk factors associated with failed sonographically guided saline hydrostatic intussusception reduction in children

OBJECTIVES

The aim of this study was to explore the risk factors associated with failed sonographically guided saline hydrostatic intussusception reduction in children.

METHODS

We retrospectively reviewed the medical records and sonograms of 288 cases of intussusception over a 3-year period. Logistic regression was used for the analysis of the clinical data (sex, age, duration of symptoms, and presence or absence of emesis or bloody stool) and sonographic features (initial location and intussusception length, presence or absence of free peritoneal fluid, and trapped fluid in the intussusception).

RESULTS

The sex, age, and duration of symptoms showed no significant impact on the hydrostatic reducibility. The success rate became significantly lower for the intussusception cases with the presence of bloody stool, free peritoneal fluid, and trapped fluid in the intussusception (P < .05). The success rate was also lower when the intussusceptions were located in the left side of the abdomen (P < .05). For the above risk factors, the odds ratios from multivariate logistic regression analysis were 174.68 for initial intussusception location in the descending colon/rectum, 36.06 for the presence of peritoneal fluid, 13.22 for trapped fluid in the intussusception, and 9.27 for the presence of bloody stool.

CONCLUSIONS

An initial intussusception location in the descending colon/rectum, the presence of peritoneal fluid, trapped fluid in the intussusception, and bloody stool are the most important risk factors for failure of sonographically guided saline hydrostatic intussusception reduction.

Fallopian tube torsion in the pediatric age group: radiologic evaluation

Fallopian tube torsion is a rare but important cause of acute pelvic pain in young adolescent girls. It is a surgical emergency treated with either detorsion or salpingectomy. The imaging findings can be nonspecific and challenging. However, an accurate early diagnosis is essential for prompt surgical treatment. Our objective was to review whether imaging findings can be specific enough to suggest the diagnosis of tubal torsion prospectively in the appropriate clinical setting. An Institutional Review Board-approved retrospective review of our imaging database from 2005 to 2012 revealed 10 surgically proven cases of fallopian tube torsion. All cases had sonography performed; 5 cases had additional multidetector computed tomography. All 10 patients (9-17 years) presented with acute pelvic pain. Sonographic findings included dilated tubular structures in 6 of 10 cases: adjacent to a normal ipsilateral ovary in 5 of 6 and adjacent to a benign ovarian teratoma in 1. In 4 cases, no dilated tube was identified; 3 of 4 had a cystic mass separate from the ovaries, and 1 had the imaging appearance of a multicystic ovary. Computed tomographic findings in the 5 cases that underwent multidetector computed tomography included a dilated tubular structure in 3 of 5; 2 of 5 had a cystic adnexal mass identified. Although rare, tubal torsion should be considered in female adolescents with acute pelvic pain. Sonography should be the first imaging choice. When a tubular structure or a midline cystic mass associated with a normal ipsilateral ovary is noted, tubal torsion should be considered in the differential diagnosis.

Relationship between isolated mild tricuspid valve regurgitation in second-trimester fetuses and postnatal congenital cardiac disorders

OBJECTIVES

In most cases, the clinical importance of fetal isolated mild tricuspid valve regurgitation is not known. This study evaluated the relationship between fetal isolated mild tricuspid regurgitation in the general obstetric population and postnatal congenital cardiac disorders.

METHODS

Detailed fetal echocardiography was done between 18 and 24 weeks' gestation to detect tricuspid regurgitation and to exclude complicated cardiac defects. Routine second-trimester targeted organ scans were also performed to exclude extracardiac defects. Follow-up was done until birth. After birth, the cardiac anatomy of the neonates was examined by echocardiography. The association between fetal isolated mild tricuspid regurgitation and postnatal congenital cardiac disorders was assessed by logistic regression analysis.

RESULTS

No major cardiac disorders were found postnatally. Some minor disorders were found, including a patent foramen ovale, atrial septal defects, a patent ductus arteriosus, and small ventricular septal defects. Fetuses with isolated mild tricuspid regurgitation had a significantly higher likelihood of having ventricular septal defects (odds ratio, 5.80; P = .027) or a patent foramen ovale with atrial septal defects and a patent ductus arteriosus (odds ratio, 11.61; P = .007). There was no significant association between tricuspid regurgitation and an isolated patent foramen ovale or a patent foramen ovale with atrial septal defects in neonates.

CONCLUSIONS

Fetuses with isolated mild tricuspid regurgitation in the second trimester did not have a higher incidence of major cardiac disorders after birth. The presence of isolated mild tricuspid regurgitation may be an indication of minor postnatal congenital cardiac disorders.