Musculoskeletal imaging in neonates: use of ultrasound.

High-resolution US is a practical, cost-effective modality to evaluate the musculoskeletal system in neonates. US can be performed portably in the neonatal intensive care unit so that the critically ill infant can be evaluated with minimal distress. Sonography is noninvasive and does not require sedation; typical questions that might require the use of MRI or CT in older children can be rapidly resolved with US. Dynamic imaging can be used in real time to stress joints and see how articular structures relate. Given the advantages of US within the neonatal population, it has been widely used to evaluate for neonatal fractures, congenital joint abnormalities, limb deficiencies as well as muscular and soft-tissue abnormalities.

Point-of-Care Ultrasound For Differentiating Ileocolic From Small Bowel-Small Bowel Intussusception.

BACKGROUND: Intussusception is a common pediatric emergency. The two types of intussusception are ileocolic intussusception (ICI) and small bowel-small bowel intussusception (SB-SBI), and neither are easily distinguished clinically. ICI requires radiology personnel and potentially surgical assistance for its reduction. SB-SBI is managed expectantly, as many resolve spontaneously. Differentiating between ICI and SB-SBI through point-of-care ultrasound (POCUS) requires an understanding of their salient features. Identification of the correct type of intussusception immediately assists decision making and patient disposition. OBJECTIVE OF THE REVIEW: Our objective was to provide guidance on POCUS technique for intussusception identification, and to review the ultrasound literature differentiating ICI from SB-SBI. METHODS: We systematically searched 3 separate databases and gray literature to identify articles that met our criteria and assessed them for final review. The final articles were graded for quality using The National Institutes of Health quality assessment tool for observational cohort and cross-sectional studies. RESULTS: A total of 858 articles were identified. Six articles were included in the final review. All studies were conducted in pediatric patients in different countries. Most were found to have a fair quality of evidence. The linear transducer is used when evaluating intussusception. Both ICI and SB-SBI are identified easily on POCUS, but they differ sonographically with respect to region within the abdomen, intussusception parameters, lymph nodes, and other salient features seen on real-time video. CONCLUSIONS: ICI and SB-SBI can be identified and differentiated using several sonographic features. POCUS is capable of expeditiously aiding the emergency physician's decision making and disposition when managing intussusception.

Mediastinal Masses in Children: Radiologic-Pathologic Correlation.

Most pediatric masses in the chest are located in the mediastinum. These masses are often initially detected incidentally on chest radiographs in asymptomatic children, although some patients may present with respiratory symptoms. At chest radiography, the mediastinum has been anatomically divided into anterior, middle, and posterior compartments. However, with the International Thymic Malignancy Interest Group classification scheme, which is based on cross-sectional imaging findings, the mediastinum is divided into prevascular, visceral, and paravertebral compartments. In the prevascular compartment, tumors of thymic origin, lymphomas, germ cell tumors, and vascular tumors are encountered. In the visceral compartment, lymphadenopathy and masses related to the foregut are seen. In the paravertebral compartment, neurogenic tumors are most common. Using the anatomic location in combination with knowledge of the imaging and pathologic features of pediatric mediastinal masses aids in accurate diagnosis of these masses to guide treatment and management decisions. An invited commentary by Lee and Winant is available online. ©RSNA, 2021.

Magnetic resonance imaging of the fetal musculoskeletal system.

Diagnosing musculoskeletal pathology requires understanding of the normal embryological development. Intrinsic errors of skeletal development are individually rare but are of paramount clinical importance because anomalies can greatly impact patients' lives. An accurate assessment of the fetal musculoskeletal system must be performed to provide optimal genetic counseling as well as to drive therapeutic management. This manuscript reviews the embryology of skeletal development and the appearance of the maturing musculoskeletal system on fetal MRI. In addition, it presents a comprehensive review of musculoskeletal fetal pathology along with postnatal imaging.

Impact of Emergency Medicine Point-of-Care Ultrasound on Radiology Ultrasound Volumes in a Single Pediatric Emergency Department.

PURPOSE: Point-of-care ultrasound (POCUS) is growing, but few data exist regarding its effects on radiology ultrasound (Rad US) volumes. The authors studied changes in Rad US ordered by emergency medicine (EM) as POCUS began and grew at their pediatric hospital. METHODS: This retrospective study included EM POCUS and EM-ordered Rad US volumes between 2011 and 2017, during three 2-year intervals: before POCUS, early POCUS, and expanded POCUS. Changes in overall Rad US and POCUS volumes per visit during these intervals were studied. Changes in skin and soft tissue infection (SSTI) US per SSTI visit, an examination performed diagnostically by both radiology and EM, were also assessed. Volume differences were examined using the Mann-Whitney U test (significance threshold, P < .05), and process control charts were used to identify nonrandom variations. RESULTS: The study included 49,908 Rad US and 2,772 POCUS examinations during 647,890 emergency department visits. Rad US volumes per visit remained unchanged during early POCUS (P = .858) but increased with expanded POCUS (P < .005). A transient nonrandom increase in Rad US occurred as POCUS began. SSTI Rad US per SSTI visit significantly increased (P < .001) during early POCUS but did not change with expanded POCUS (P = .143). An SSTI management pathway in the emergency department before expanded POCUS may have affected ordering. Other variation occurred in proximity to practice changes and seasonal patterns. CONCLUSIONS: Rad US overall and specifically for SSTI increased or remained stable during the introduction and growth of EM POCUS. Rather than decreasing Rad US, EM POCUS had a complementary role.

Imaging Intussusception in Children's Hospitals in the United States: Trends, Outcomes, and Costs.

OBJECTIVE: To describe imaging utilization, outcomes, and cost in the management of intussusception between 2010 and 2017 in pediatric hospitals in the United States. METHODS: All children (under 18 years of age) with a primary diagnosis of intussusception in a large administrative database were identified. Demographics, imaging, and costs were described. RESULTS: There were 17,032 children (63.3% boys, 36.7% girls, mean age: 3.2 years) that had 20,655 hospital encounters for intussusception, and 88.5% were <5 years of age. The average length of stay was 2.8 days (median: 1 day), with rates of intensive care unit admission, 3.7%; 90-day readmission, 10.5%; and mortality, 0.2%. The surgical rate was 19.6%, and 93.5% (n = 19,301) of patients underwent imaging: 87.2% (n = 16,822) received ultrasound, 69.1% (n = 13,329) had fluoroscopy, 59% (n = 11,380) had abdominal radiographs, and 8.8% (n = 1,696) had CT. The reduction success rate for fluoroscopy was 77.9%. Surgery was more common in rural patients (26.8% versus 18.7% in urban patients, P < .001). Median encounter costs were $2,675 (interquartile range: $1,637-$5,465). Imaging cost represented a quarter (median $680, interquartile range: $372-1,069) of all costs. Higher costs (median) were associated with longer length of stay (<3 days: $858 versus >3 days: $5,342; use of CT ($4,168 versus $943 in patients without a CT), and surgery ($4,434 versus $860 without surgery). CONCLUSION: The management of intussusception is mainly nonsurgical, most frequently involving imaging with ultrasound and fluoroscopy, and resulting in excellent outcomes in the great majority of the cases. Despite playing a central role for diagnosis and management, imaging only represents a fraction of total cost.

Identifying infant hydrocephalus in the emergency department with transfontanellar POCUS.

Hydrocephalus carries significant morbidity in the infant population. Although clinical symptoms are often nonspecific, hydrocephalus is easily identified using transfontanellar sonography. In this review, we provide the emergency physician with a succinct overview of infant hydrocephalus and the point-of-care ultrasound (POCUS) technique for identification of this pathology.

MRI of the bowel - beyond inflammatory bowel disease.

MR enterography is traditionally used to evaluate inflammatory bowel disease (IBD) both at initial presentation and at follow-up. MR enterography can also be used to evaluate non-IBD conditions such as polyps or other masses of the gastrointestinal tract. In this article, we emphasize how to recognize bowel conditions beyond IBD on conventional abdominal MRI without a specific enterographic technique. In this overview we discuss common and uncommon pediatric bowel conditions beyond IBD seen on MRI including infectious and inflammatory conditions, congenital diseases and tumor and tumor-like conditions. Radiologists should become familiar with the salient imaging features of these bowel conditions to help guide management.

Ankle and Foot Injuries in the Young Athlete.

Injuries to the ankle and foot are common in the young athlete, especially with increasing participation and high levels of competitiveness in youth sports programs. Knowledge of the normal development of the foot and ankle is crucial to understand age-specific injury patterns because acute or chronic/repetitive stress to the developing skeleton results in injuries that differ from those seen in adults. Congenital abnormalities may also predispose children to increased risk of injury and pain. Radiologists must be aware of these distinctions to diagnose and classify injuries correctly for optimum treatment. We describe common and unique foot and ankle injuries in the young athlete. Throughout the article we focus not only on imaging findings but also on the mechanism of injury.

Ultrasound of congenital and inherited disorders of the pediatric hepatobiliary system, pancreas and spleen.

Ultrasound is often the initial imaging examination performed of the solid organs of the pediatric abdomen. The sonographic appearance of the hepatobiliary system, pancreas and spleen changes with growth and development. This article reviews the normal US appearance of these organs in children and illustrates, through case examples, congenital and inherited conditions that affect them.

Pelvic pain in the middle of the night: use of MRI for evaluation of pediatric female pathology in the emergent setting.

Acute pelvic pain in pediatric female patients is a common cause of emergency room visits. Imaging plays a crucial role in the clinical evaluation of these patients. Pelvic pain in female children can result from various pathologies. Ultrasound is the preferred first line imaging study; however, magnetic resonance imaging (MRI) is a helpful adjunct after hours, as it is available 24/7 in many institutions. Advantages of MRI include superior delineation of anatomy and higher tissue contrast resolution, particularly of the small pelvic structures. Given the lack of ionizing radiation, there is increasing use of MRI in children and adolescents, specifically in an emergent setting. In this pictorial review, we discuss pelvic MRI techniques and illustrate imaging findings of common etiologies of pelvic pain, emphasizing the advantages of MRI as an adjunct imaging modality.

Imaging of Inflammatory Arthritis in Children: Status and Perspectives on the Use of Ultrasound, Radiographs, and Magnetic Resonance Imaging.

The hallmark of juvenile idiopathic arthritis is synovial inflammation, and the goal of treatment is to suppress inflammation to prevent cartilage damage and bone erosions. Ultrasound and MRI are widely used imaging modalities in evaluating disease burden and response to treatments and are superior to clinical examination alone. However, differentiating between the normal appearance of the developing skeleton and pathologic conditions can be difficult, particularly in early disease. Larger, long-term studies are needed to standardize imaging definitions and protocols and to fully understand the clinical implications of imaging findings.

Magnetic resonance imaging of pancreaticobiliary diseases in children: from technique to practice.

Magnetic resonance imaging is useful for evaluating pancreaticobiliary diseases in children after initial sonography, obviating the use of ionizing radiation or invasive procedures such as endoscopic retrograde cholangiopancreatography (ERCP) or transhepatic biliary procedures. Advanced MRI applications have improved depiction of pediatric pancreaticobiliary anatomy and have greatly impacted management of biliary and pancreatic diseases in children. In this article, we review current MRI and magnetic resonance cholangiopancreatography (MRCP) techniques and discuss their role in the assessment of common pancreatic and biliary disorders in children.

Imaging findings of Hoffa's fat pad herniation.

BACKGROUND: We report the radiologic findings of herniation of Hoffa's fat pad through a defect in the lateral patellar retinaculum in young children who presented with painless masses visible by ultrasound (US) only with flexion of the knee. MATERIAL AND METHODS: Six children, between the ages of 1-8 years, presented with an anterolateral knee mass that was not tender and was only seen and palpable with knee flexion. An US was performed in all patients, magnetic resonance imaging (MRI) in 2 patients and knee radiographs in 1 patient. RESULTS: US imaging displayed focal herniation of Hoffa's fat pad within the infrapatellar region through a defect of the lateral retinaculum, visible only during dynamic imaging when the knee was in flexion. MRI performed in knee extension did not demonstrate a mass; however, it revealed a focal defect in the lateral retinaculum in the region of the abnormality. Radiographs were normal. CONCLUSION: Focal herniation of Hoffa's fat pad is an uncommon cause of an anterolateral knee mass in young children. When a knee mass is only identified in flexion, focal fat herniation through a defect in the retinaculum should be suspected and a dynamic US should be performed.

Common and uncommon applications of bowel ultrasound with pathologic correlation in children.

OBJECTIVE: The purpose of this article is to describe the indications and techniques for bowel ultrasound for inflammatory bowel disease and other common and uncommon entities and describe and illustrate their imaging appearances, including endoscopic or surgical correlation. CONCLUSION: Ultrasound is a useful tool for the evaluation of inflammatory bowel disease and many other bowel diseases. Radiologists must become familiar with the full potential of ultrasound in the evaluation of the bowel in children because the need for alternative radiation-free imaging techniques continues to grow.