Search

Thoracic outlet syndrome (TOS) is a clinical disorder resulting from compression of the neurovascular bundle of the lower neck and upper chest. TOS can be categorized into neurogenic, venous, and arterial subtypes which result from anatomical compression of the brachial plexus, subclavian vein, and subclavian artery, respectively. This can lead to neurogenic pain as well as vascular injury with thrombosis and thromboembolism. Interventional and diagnostic radiologists play a critical role in the imaging diagnosis and treatment of vascular TOS. Prompt imaging and endovascular management with surgical collaboration has been shown to provide the most successful and long-lasting clinical outcomes, from vessel patency to symptom relief. In this article, we review the anatomy and clinical presentations of TOS as well as the initial imaging modalities used for diagnosis. Furthermore, we detail the role of the diagnostic and interventional radiologist in the management of TOS, including pre-procedure and endovascular interventions, along with medical and surgical treatments. PRECIS: Diagnostic and Interventional Radiologists play a key role in diagnosis and management of vascular thoracic outlet syndromes and are critical for timely and successful outcomes.

Rational and Objectives Ultrasound investigation of peripheral nerves, long used in the adult population, has been shown to be of value in diagnosing a variety of peripheral nerve abnormalities. More recently, nerve sonography has also been shown to be of use in pediatrics. However, normative values for nerve size in children have been lacking. As such, the goal of this research was to establish normative data for cross sectional area (CSA) measurements of the median and ulnar nerves in children. Materials and methods The median and ulnar nerves of 48 children ranging in age from 2 years to 17 years were imaged by ultrasound. CSA measurements were made at 2 separate sites for each nerve and measured independently by 6 pediatric radiologists. Reliability of ultrasound measurements between the radiologists was assessed by calculating intraclass correlation coefficients. Linear mixed-effects modeling was performed to develop prediction models for nerve cross sectional area for each nerve segment; 95% prediction values were generated from these models to approximate normal ranges. Results Agreement in nerve cross-sectional area measurements among the 6 radiologists for all nerve segments was good (ICC 0.82, 95% CI 0.78 to 0.85). CSA for both the median and ulnar nerves is larger in older children. However, statistical models to predict CSA using height perform better rather than those using a child's age. The range of normal nerve segment CSA using these prediction models based on child height are reported. Conclusion Median and ulnar nerve CSA can be reliably measured with ultrasound. Normal reference values for ulnar and median nerve CSA correlate with patient age but may be more optimally determined based on a child's height.

Child abuse is a broad term that includes, but is not limited to, physical or emotional harm, neglect, sexual abuse, and exploitation. In 2018 in the United States, there were nearly 700,000 victims of such maltreatment, of which 1700 children died. The majority of deaths occur in infants and toddlers under 3 years of age. While clinical signs and symptoms may raise suspicion for inflicted injury, such as bruising in young infants, imaging often plays a central role in identifying and characterizing nonaccidental trauma. The purpose of this article is to discuss the array of inflicted traumatic injuries to the thorax in children. Rib fractures are among the most common and telling features of physical abuse, especially in infants. The locations of such fractures and differences in appearance while healing will be presented, along with potential mimics and pitfalls. Less typical fractures seen in abuse will also be reviewed, including those of the sternum, clavicle, spine, and scapula. Finally, uncommon injuries to the lungs, heart and esophagus will also be considered.

Background Pediatric patients with optic pathway gliomas (OPGs) typically undergo a large number of follow-up MRI brain exams with gadolinium-based contrast media (GBCM), which have been associated with gadolinium tissue retention. Therefore, careful consideration of GBCM use in these children is warranted. Objective To investigate whether GBCM is necessary for OPG MR imaging response assessment using a blinded, non-inferiority, multi-reader study. Materials and methods We identified children with OPG and either stable disease or change in tumor size on MRI using a regional cancer registry serving the U.S. Pacific Northwest. For each child, the two relevant, consecutive MRI studies were anonymized and standardized into two imaging sets excluding or including GBCM-enhanced images. Exam pairs were compiled from 42 children with isolated OPG (19 with neurofibromatosis type 1), from a population of 106 children with OPG. We included 28 exam pairs in which there was a change in size between exams. Seven pediatric radiologists measured tumor sizes during three blinded sessions, spaced by at least 1 week. The first measuring session excluded GBCM-enhanced sequences; the others did not. The primary endpoint was intra-reader agreement for ≥ 25% change in axial cross-product measurement, using a 12% non-inferiority threshold. Results Analysis demonstrated an overall 1.2% difference (95% confidence interval, -3.2% to 5.5%) for intra-reader agreement using a non-GBCM-enhanced protocol and background variability. Conclusion A non-GBCM-enhanced protocol was non-inferior to a GBCM-enhanced protocol for assessing change in size of isolated OPGs on follow-up MRI exams.

Purpose To compare the direct bundled costs of interventional radiology (IR) suite versus bedside placement of noncuffed central venous catheters in infants. Methods A single-center retrospective review was performed of all noncuffed upper extremity (peripherally inserted central venous catheter [PICC]) and tunneled femoral (tunneled femoral central venous catheter [TCVC]) catheters placed in infants between January 1, 2018, and December 31, 2018. Propensity score matching was performed adjusting for age, birth weight, procedure weight, and catheter days. Process maps for each procedure were created based on location and sedation type. Technical success and complications were recorded for each placement. The total direct bundled cost for each catheter placement was calculated by summing the procedure and complication costs. Results A total of 142 procedures were performed on 126 matched patients with a technical success of 96% at the bedside and 100% in the IR suite (P = .08). The complication rates did not significantly differ between the 2 groups (P = .51). The total direct bundled costs for catheter placement were $1421.3 ± 2213.2 at the bedside and $2256.8 ± 3264.7 in the IR suite (P = .001). Conclusions The bundled cost of bedside femoral catheter placement is significantly less than that of fluoroscopic TCVC and PICC placement performed in the IR suite, mainly related to differences in sedation costs.

Malignant primary bone tumors are uncommon in the pediatric population, accounting for 3%-5% of all pediatric malignancies. Osteosarcoma and Ewing sarcoma comprise 90% of malignant primary bone tumors in children and adolescents. This paper provides consensus-based recommendations for imaging in children with osteosarcoma and Ewing sarcoma at diagnosis, during therapy, and after therapy.

Brachial plexus birth injury can lead to irreversible neuromuscular dysfunction and skeletal deformity of the upper extremity and shoulder girdle, ultimately resulting in glenohumeral dysplasia. Diagnosis and treatment of affected infants requires a multi-disciplinary approach in which imaging plays a vital role. While MRI is excellent for assessing both the shoulder and spine of these children, it is costly and requires sedation and is thus typically reserved for preoperative planning. US, however, is inexpensive, dynamic and readily available and provides excellent visualization of the largely cartilaginous glenohumeral joint. As such, it has become a highly useful modality during early diagnosis and follow-up of children with brachial plexus birth injuries. In this review, we describe the relevant anatomy of the glenohumeral joint, outlining the normal sonographic appearance as well as providing tips and tricks for identifying and characterizing pathology.

The spectrum of pathologies affecting the biliary tree in the pediatric population varies depending on the age of presentation. While in utero insults can result in an array of anatomic variants and congenital anomalies in newborns, diverse acquired biliary pathologies are observed in older children. These acquired pathologies display different presentations and consequences than adults. Multimodality imaging assessment of the pediatric biliary system is requisite to establishing an appropriate management plan. Awareness of the imaging features of the various biliary pathologies and conveying clinically actionable information is essential to facilitate appropriate patient management. In this paper, we will illustrate the anatomy and embryology of the pediatric biliary system. Then, we will provide an overview of the imaging modalities used to assess the biliary system. Finally, we will review the unique features of the pediatric biliary pathologies, complemented by histopathologic correlation and discussions of clinical management.

ObjectiveTo standardize and improve the accuracy of detection of arthritis by thermal imaging.MethodsChildren with clinically active arthritis in the knee or ankle, as well as healthy controls, were enrolled to the development cohort; another group of children with knee symptoms was enrolled to the validation cohort. Ultrasound was performed in the arthritis subgroup for the development cohort. Joint exam by certified rheumatologists was used as a reference for the validation cohort. Infrared thermal data were analyzed using custom software. Temperature after within-limb calibration (TAWiC) was defined as the temperature differences between joint and ipsilateral mid-tibia. TAWiC of knees and ankles was evaluated using ANOVA across subgroups. Optimal thresholds were determined by receiver-operating characteristic analysis using Youden index.ResultsThere were significant differences in mean and 95th TAWiC of knee in anterior, medial, lateral views, and of ankles in anterior view, between inflamed and uninflamed counterparts (P < 0.05). The area under the curve was higher by 30% when using TAWiCknee than that when using absolute temperature. Within the validation cohort, the sensitivity of accurate detection of arthritis in the knees using both mean and 95th TAWiC from individual views or all 3 views combined ranged from 0.60 to 0.70, and the specificity was > 0.90 in all views.ConclusionChildren with active arthritis or tenosynovitis in knees or ankles exhibited higher TAWiC than healthy joints. Our validation cohort study showed promise for the clinical utility of infrared thermal imaging for arthritis detection.

On March 30, 2022, the U.S. FDA issued a drug safety communication recommending that infants and young children through 3 years of age undergo monitoring of thyroid function within 3 weeks of intravascular administration of iodine-based contrast media. This article considers the literature that was referenced for this decision and provides an outlook on thyroid monitoring after diagnostic imaging from pediatric radiology and pediatric endocrinology perspectives.

Pediatric pulmonary malignancy can be primary or metastatic, with the latter being by far the more common. With a few exceptions, there are no well-established evidence-based guidelines for imaging pediatric pulmonary malignancies, although computed tomography (CT) is used in almost all cases. The aim of this article is to provide general imaging guidelines for pediatric pulmonary malignancies, including minimum standards for cross-sectional imaging techniques and specific imaging recommendations for select entities.

Pediatric soft tissue tumors of the extremity include rhabdomyosarcoma and nonrhabdomyosarcoma neoplasms. This manuscript provides consensus-based imaging recommendations for imaging evaluation at diagnosis, during treatment, and following completion of therapy for patients with a soft tissue tumor of the extremity.

Pathologies involving the ribs are diverse in nature, including entities specific to the pediatric population as well as shared pathologies with adults. These can be either localized within or adjacent to the rib, but may also cause rib alteration as a component of a systemic process. To better understand these disorders, we discuss several common rib pathologies in the context of their clinical presentation and pertinent imaging findings. In addition, we review the imaging modalities that may be used to evaluate the ribs. Encompassing both the clinical and imaging aspects of pediatric rib pathologies, this review aims to increase pediatric and musculoskeletal radiologists' awareness of the spectrum of disease and how to leverage a pattern-based approach.

Artificial intelligence (AI) is a broad and complicated concept that has begun to affect many areas of medicine, perhaps none so much as radiology. While pediatric radiology has been less affected than other radiology subspecialties, there are some well-developed and some nascent applications within the field. This review focuses on the use of AI within pediatric radiology for image interpretation, with descriptive summaries of the literature to date. We highlight common features that enable successful application of the technology, along with some of the limitations that can inhibit the development of this field. We present some ideas for further research in this area and challenges that must be overcome, with an understanding that technology often advances in unpredictable ways.

In skeletally immature patients, the presence of growth plates and articular cartilage of the shoulder can create a predisposition for unique injuries not observed in adults. Furthermore, increasing participation in sports by children and adolescents appears to be leading to a corresponding increase in the number of sports-related injuries. The importance of radiologists being familiar with pediatric shoulder imaging and its associated injuries is therefore growing. In this article, we review the normal development and maturation pattern of ossification centers of the shoulder from the early gestational period through adolescence. Brachial plexus birth palsy, physeal injuries, shoulder dislocation, and internal impingement are discussed within the context of the child's age and the mechanism of injury to guide radiologists to a correct diagnosis.

We describe a unique case of focal nodular hyperplasia (FNH) in a 6-month-old-girl with elevated alpha-fetoprotein (AFP). Given the patient's age and elevated AFP, a diagnosis of hepatoblastoma was presumed. However, the histopathologic assessment of the lesion was typical for focal nodular hyperplasia. This was further corroborated using hepatobiliary contrast agent to exclude the possibility of a collision or a composite liver tumor.

Vomiting in infants under the age of 3 months is one of the most common reasons for parents to seek care from their doctor or present to an emergency room. The imaging workup that ensues is dependent on several factors: age at onset, days versus weeks after birth, quality of emesis, bilious or nonbilious vomiting, and the initial findings on plain radiograph, suspected proximal versus distal bowel obstruction. The purpose of these guidelines is to inform the clinician, based on current evidence, what is the next highest yield and most appropriate imaging study to pursue a diagnosis. The goal is rapid and accurate arrival at a plan for treatment, whether surgical or nonsurgical. The following modalities are discussed for each variant of the symptom: plain radiography, fluoroscopic upper gastrointestinal series, fluoroscopic contrast enema, ultrasound of the abdomen, nuclear medicine gastroesophageal reflux scan. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Antenatal hydronephrosis is the most frequent urinary tract anomaly detected on prenatal ultrasonography. It occurs approximately twice as often in males as in females. Most antenatal hydronephrosis is transient with little long-term significance, and few children with antenatal hydronephrosis will have significant obstruction, develop symptoms or complications, and require surgery. Some children will be diagnosed with more serious conditions, such as posterior urethral valves. Early detection of obstructive uropathy is necessary to mitigate the potential morbidity from loss of renal function. Imaging is an integral part of screening, diagnosis, and monitoring of children with antenatal hydronephrosis. Optimal timing and appropriate use of imaging can reduce the incidence of late diagnoses and prevent renal scarring and other complications. In general, follow-up neonatal ultrasound is recommended for all cases of antenatal hydronephrosis, while further imaging, including voiding cystourethrography and nuclear scintigraphy, is recommended for moderate or severe cases, or when renal parenchymal or bladder wall abnormalities are suspected. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Common cause analysis of hospital safety events that involve radiology can identify opportunities to improve quality of care and patient safety. To study the most frequent system failures as well as key activities and processes identified in safety events in an academic children’s hospital that underwent root cause analysis and in which radiology was determined to play a contributing role. All safety events involving diagnostic or interventional radiology from April 2013 to November 2018, for which the hospital patient safety department conducted root cause analysis, were retrospectively analyzed. Pareto charts were constructed to identify the most frequent modalities, system failure modes, key processes and key activities. In 19 safety events, 64 sequential interactions were attributed to the radiology department by the patient safety department. Five of these safety events were secondary to diagnostic errors. Interventional radiology, radiography and diagnostic fluoroscopy accounted for 89.5% of the modalities in these safety events. Culture and process accounted for 55% of the system failure modes. The three most common key processes involved in these sequential interactions were diagnostic (39.1%) and procedural services (25%), followed by coordinating care and services (18.8%). The two most common key activities were interpreting/analyzing (21.9%) and coordinating activities (15.6%). Proposing and implementing solutions based on the analysis of a single safety event may not be a robust strategy for process improvement. Common cause analyses of safety events allow for a more robust understanding of system failures and have the potential to generate more specific process improvement strategies to prevent the reoccurrence of similar errors. Our analysis demonstrated that the most common system failure modes in safety events attributed to radiology were culture and process. However, the generalizability of these findings is limited given our small sample size. Aligning with other children’s hospitals to use standard safety event terminology and shared databases will likely lead to greater clarity on radiology’s direct and indirect contributions to patient harm.

The ACR recognizes that radiology practices are grappling with when and how to safely resume routine radiology care during the coronavirus disease 2019 (COVID-19) pandemic. Although it is unclear how long the pandemic will last, it may persist for many months. Throughout this time, it will be important to perform safe, comprehensive, and effective care for patients with and patients without COVID-19, recognizing that asymptomatic transmission is common with this disease. Local idiosyncrasies prevent a single prescriptive strategy. However, general considerations can be applied to most practice environments. A comprehensive strategy will include consideration of local COVID-19 statistics; availability of personal protective equipment; local, state, and federal government mandates; institutional regulatory guidance; local safety measures; health care worker availability; patient and health care worker risk factors; factors specific to the indication(s) for radiology care; and examination or procedure acuity. An accurate risk-benefit analysis of postponing versus performing a given routine radiology examination or procedure often is not possible because of many unknown and complex factors. However, this is the overriding principle: If the risk of illness or death to a health care worker or patient from health care-acquired COVID-19 is greater than the risk of illness or death from delaying radiology care, the care should be delayed; however, if the opposite is true, the radiology care should proceed in a timely fashion.

OBJECTIVE. Any combination of abnormal positioning of the ankle, hindfoot, midfoot, and forefoot is possible in the context of cerebral palsy, but some patterns are more common than others. The purpose of this article is to discuss the radiographic manifestations and surgical management of the following common conditions: equinus, equinoplanovalgus, equinocavovarus, vertical talus, oblique talus, hallux valgus, and ankle valgus. CONCLUSION. CP is defined by abnormalities of the developing fetal or infant brain that result in permanent central motor dysfunction. Foot and ankle deformities are very common in the patients with CP, occurring in up to 93% of such patients as a result of underlying abnormal muscle tone, impaired motor control, and dynamic muscle imbalance. Radiologists must develop knowledge of the most common changes in alignment and basic techniques for correction to better recognize abnormalities and improve communication with orthopedic colleagues.

Pneumonia is one of the most common acute infections and the single greatest infectious cause of death in children worldwide. In uncomplicated, community-acquired pneumonia in immunocompetent patients, the diagnosis is clinical and imaging has no role. The first role of imaging is to identify complications associated with pneumonia such as pleural effusion, pulmonary abscess, and bronchopleural fistula. Radiographs are recommended for screening for these complications and ultrasound and CT are recommended for confirmation. The second role of imaging is to identify underlying anatomic conditions that may predispose patients to recurrent pneumonia. CT with intravenously administered contrast is recommended for this evaluation. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Cough and respiratory infections are common in pediatrics. Our case report illustrates the need for pediatricians to consider rare diagnoses such as genetic syndromes and primary gastrointestinal motility disorders in patients with unremitting respiratory and gastrointestinal symptoms. Early identification provides early intervention and reduces long‐term morbidity for pediatric patients.

OBJECTIVE. The purpose of this article is to describe the imaging findings associated with complex fetal abdominal wall defects and provide an algorithmic method for arriving at a final diagnosis. CONCLUSION. Fetal ventral abdominal wall defects are a complex group of conditions with a broad spectrum of associated multisystem anomalies and manifestations. Correct characterization and classification of these defects require not only familiarity with imaging findings but also a systematic approach to avoid diagnostic confusion.

ObjectiveChronic nonbacterial osteomyelitis (CNO) is a rare autoinflammatory bone disease that is gaining recognition from clinicians and researchers. We aim to publish data from our cohort of patients with CNO living in the northwestern United States to increase the awareness of specific demographics, characteristics, and presentation of this rare disease.MethodsA retrospective chart review was performed of our electronic medical records. Patients with complete chart records who met criteria for a diagnosis of CNO from 2005 to 2019 were included. Extracted data including patient demographics, bone biopsy results, and lesion locations on advanced imaging were analyzed. King County census data were used to calculate the annual new case rate within our center.ResultsA total of 215 CNO cases were diagnosed at our large tertiary pediatric hospital. The majority of cases were of White race residing in Washington’s most populous county, King County. Most cases were diagnosed in 2016 to 2019, showing a significant increase in the annual case rate from 8 to 23 per million children in King County, though there did not appear to be a seasonal predilection. Biopsy rate decreased from 75% to 52%. One hundred fifty-two (71%) children had family history of autoimmunity. With increasing use of whole-body magnetic resonance imaging (WB-MRI), results showed 68% had multiple lesions.ConclusionCNO has been diagnosed at an increased rate in recent years. WB-MRI may assist in identifying other lesions that may be asymptomatic on presentation. Bone biopsy is still required in some children at the time of diagnosis.

Chronic recurrent multifocal osteomyelitis (CRMO) is a diagnosis of exclusion, relying heavily on whole-body magnetic resonance imaging (WB-MRI) for diagnosing and evaluating response to therapy. Information with respect to disease distribution and imaging correlation with clinical disease severity at initial presentation is lacking.To retrospectively characterize distribution of disease on WB-MRI and to correlate imaging findings with disease severity at initial rheumatology presentation.Using a modified version of a recently devised imaging-based scoring system, we evaluated disease distribution and correlation between findings on WB-MRI and clinical disease severity in 54 patients presenting for initial evaluation of CRMO. Symptomatic lesion sites were extracted from chart review and physician global assessment was determined by the consensus of two rheumatologists.Sites of CRMO involvement evident on imaging at initial presentation had a strong predilection for the pelvis and lower extremities. There was significant correlation between the number of lesions detected on WB-MRI and total clinical severity score at initial rheumatology presentation (Plt;0.01). However, no other imaging parameter correlated with disease severity.While the overall number of lesions identified on MRI correlates with clinical severity scores at initial imaging, other MR parameters of CRMO lesions may not be reliable indicators of disease severity at initial presentation. Further research is needed to assess whether these parameters are implicated in longitudinal disease severity or overall response to therapy.

Pediatric chest wall lesions are varied in etiology ranging from normal and benign to aggressive and malignant. When palpable, these lesions can alarm parents and clinicians alike. However, most palpable pediatric chest lesions are benign. Familiarity with the various entities, their incidences, and how to evaluate them with imaging is important for clinicians and radiologists. Here we review the most relevant palpable pediatric chest entities, their expected appearance and the specific clinical issues to aid in diagnosis and appropriate treatment.

Rationale and Objectives To determine if, during the first wave of the COVID-19 pandemic, 1) the proportion of complicated appendicitis changed, and 2) if imaging strategies for appendicitis in children changed. Materials and Methods Retrospective cross-sectional study using administrative data from the Pediatric Health Information System, inclusive of pediatric patients diagnosed with appendicitis from March to May in 2017, 2018, 2019 and 2020. We compared trends during COVID-19 pandemic (March-May 2020) with corresponding pre-COVID-19 periods in 2017-2019. Study outcomes were the proportion of complicated appendicitis and trends in imaging for appendicitis explained by patient-level variables. Results The proportion of complicated appendicitis cases increased by 4.4 percentage points, from 46.5% pre-COVID-19 (2017-2019) to 50.9% during COVID-19 (2020), p

Scoliosis is frequently encountered in childhood, with prevalence of 2%. The majority is idiopathic, without vertebral segmentation anomaly, dysraphism, neuromuscular abnormality, skeletal dysplasia, tumor, or infection. As a complement to clinical assessment, radiography is the primary imaging modality used to classify scoliosis and subsequently monitor its progression and response to treatment. MRI is utilized selectively to assess for neural axis abnormalities in those at higher risk, including those with congenital scoliosis, early onset idiopathic scoliosis, and adolescent idiopathic scoliosis with certain risk factors. CT, although not routinely employed in the initial evaluation of scoliosis, may have a select role in characterizing the bone anomalies of congenital scoliosis and in perioperative planning. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Acute appendicitis represents the most common abdominal surgical urgency/emergency in children. Imaging remains a central tool in the diagnosis of acute appendicitis and has been shown to facilitate management and decrease the rate of negative appendectomies. The initial consideration for imaging in a child with suspected acute appendicitis is based on clinical assessment, which can be facilitated with published scoring systems. The level of clinical risk (low, intermediate, high) and the clinical scenario (suspicion for complication) define the need for imaging and the optimal imaging modality. In some situations, no imaging is required, while in others ultrasound, CT, or MRI may be appropriate. This review frames the presentation of suspected acute appendicitis in terms of the clinical risk and also discusses the unique situations of the equivocal or nondiagnostic initial ultrasound examination and suspected appendicitis with suspicion for complication (eg, bowel obstruction). The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Administration of intravenous contrast media to children is a routine practice at many clinical imaging centers, that can involve special considerations. In this paper, we provide practical information to facilitate optimal performance and oversight of this task. We provide targeted screening questions that can help to identify high-risk pediatric patients for both iodine-based and gadolinium-based intravenous contrast media administration. These include children at risk for allergic-like reactions, thyroid dysfunction, contrast-induced nephropathy, and nephrogenic systemic fibrosis. We make recommendations for addressing "yes" responses to screening questions using risk stratification schema that are specific to children. We also present criteria for selecting children for premedication prior to intravenous contrast administration, and suggest pediatric regimens. Additionally, we discuss practical nuances of intravenous contrast media administration to children and provide a quick-reference table of appropriate treatments with pediatric dosages for adverse contrast reactions.

Magnetic resonance imaging is a multipurpose imaging modality that is largely safe, given the lack of ionizing radiation. However there are electromagnetic and biological effects on human tissue when exposed to magnetic environments, and hence there is a risk of adverse events occurring with these exams. It is imperative to understand these risks and develop methods to minimize them and prevent consequent adverse events. Implementing these safety practices in pediatric MR imaging has been somewhat limited because of gaps in information and knowledge among the personnel who are closely involved in the MR environment. The American College of Radiology has provided guidelines on MR safety practices that are helpful in minimizing such adverse events. This article provides an overview of the issues related to MR safety and practical ways to implement them across different health care facilities.

Clinical decision support has been identified by the United States government as a method to decrease inappropriate imaging exams and promote judicious use of imaging resources. The adoption of this method will be incentivized by requiring appropriate use criteria to qualify for Medicare reimbursement starting in January 2020. While Medicare reimbursement is unlikely to directly impact pediatric imaging because of largely disparate patient populations, insurance providers typically use Medicare to benchmark their reimbursement guidelines. Therefore soon after their adoption these guidelines could become relevant to pediatric imaging. In this article we discuss how pediatric imaging was initially underrepresented in the clinical decision support realm, and how this was addressed by a subcommittee involving both American College of Radiology and Society for Pediatric Radiology members. We also present the experience of implementing clinical decision support software at two standalone pediatric hospitals and summarize the lessons learned from these deployments.

Peer learning represents a shift away from traditional peer review. Peer learning focuses on improvement of diagnostic performance rather than on suboptimal performance. The shift in focus away from random selection and toward identification of cases with valuable teaching points can encourage more active radiologist engagement in the learning process. An effective peer learning program relies on a trusting environment that lessens the fear of embarrassment or punitive action. Here we describe the shortcomings of traditional peer review, and the benefits of peer learning. We also provide tips for a successful peer learning program and examples of implementation.

Gadolinium has been used as a base for contrast agents in MRI for the last three decades. Numerous studies over the last 4 years have reported increased signal intensity in deep brain nuclei in non-contrast MRI images following gadolinium-based contrast agent (GBCA) administration. Pathology studies performed on adults and children, and rodent necropsy studies have also shown gadolinium deposition in brain and other tissues after GBCA administration. The purpose of this review was to summarize and discuss the knowledge gained from these reports and the relevance for imaging pediatric patients.

Clinical decision support is a way to decrease inappropriate imaging exams and promote judicious use of imaging resources. The adoption of clinical decision support will be incentivized by requiring the use of approved mechanisms to qualify for Medicare reimbursement starting in January 2020. Insurance providers base their reimbursement policies on Medicare, so clinical decision support could soon become relevant to pediatric imaging. We present the process behind the American College of Radiology (ACR) Appropriateness Criteria (a set of appropriate use criteria developed by the ACR) that will form the basis for software that can be used to fulfill the criteria for clinical decision support. For most organizations, this software is expected to be the easiest way to implement clinical decision support. Clinical decision support will affect how providers order imaging exams. This article should help readers understand how clinical decision support is expected to change the practice of the ordering providers, how the ACR Appropriateness Criteria are related to clinical decision support and how the ACR Appropriateness Criteria are developed. This will help the interpreting radiologist better communicate with the referring clinician, including informing the latter about how the clinical decision support software is making decisions.