Pediatric Abdominal Masses: Imaging Guidelines and Recommendations.

Pediatric abdominal masses are commonly encountered in the pediatric population, with a broad differential diagnosis that encompasses benign and malignant entities. The primary role of abdominal imaging in the setting of a suspected pediatric abdominal mass is to establish its presence, as nonneoplastic entities can mimic an abdominal mass, and to identify characteristic imaging features that narrow the differential diagnosis. In the setting of a neoplasm, various imaging modalities play an important role to characterize the mass, stage extent of disease, and assist in presurgical planning. The purpose of this article is to discuss a practical imaging algorithm for suspected pediatric abdominal masses and to describe typical radiological findings of the commonly encountered abdominal masses in neonates and children with emphasis on imaging guidelines and recommendations.

Pediatric SARS, H1N1, MERS, EVALI, and Now Coronavirus Disease (COVID-19) Pneumonia: What Radiologists Need to Know.

OBJECTIVE. The purpose of this article is to review new pediatric lung disorders-including disorders that have occurred in recent years years such as severe acute respiratory syndrome (SARS), swine-origin influenza A (H1N1), Middle East respiratory syndrome (MERS), e-cigarette or vaping product use-associated lung injury (EVALI), and coronavirus disease (COVID-19) pneumonia-to enhance understanding of the characteristic imaging findings. CONCLUSION. Although the clinical symptoms of SARS, H1N1, MERS, EVALI, and COVID-19 pneumonia in pediatric patients may be nonspecific, some characteristic imaging findings have emerged or are currently emerging. It is essential for radiologists to have a clear understanding of the characteristic imaging appearances of these lung disorders in pediatric patients to ensure optimal patient care.

Reliability of Measuring Insertion Depth in Cochlear Implanted Infants and Children Using Cochlear View Radiography.

OBJECTIVES: Cochlear implant depth of insertion affects audiologic outcomes and can be measured in adults using plain films obtained in the "cochlear view." The objective of this study was to assess interrater and intrarater reliability of measuring depth of insertion using cochlear view radiography. STUDY DESIGN: Prospective, observational. SETTING: Tertiary referral pediatric hospital. SUBJECTS AND METHODS: Patients aged 11 months to 20 years (median, 4 years; interquartile range [IQR], 1-8 years) undergoing cochlear implantation at our institution were studied over 1 year. Children underwent cochlear view imaging on postoperative day 1. Films were deidentified and 1 image per ear was selected. Two cochlear implant surgeons and 2 radiologists evaluated each image and determined angular depth of insertion. Images were re-reviewed 6 weeks later by all raters. Inter- and intrarater reliability were calculated with intraclass correlation coefficients (ICCs). RESULTS: Fifty-seven ears were imaged from 42 children. Forty-nine ears (86%) had successful cochlear view x-rays. Median angular depth of insertion was 381° (minimum, 272°; maximum, 450°; IQR, 360°-395°) during the first round of measurement. Measurements of the same images reviewed 6 weeks later showed median depth of insertion of 382° (minimum, 272°; maximum, 449°; IQR, 360°-397°). Interrater and intrarater reliability ICCs ranged between 0.81 and 0.96, indicating excellent reliability. CONCLUSIONS: Postoperative cochlear view radiography is a reliable tool for measurement of cochlear implant depth of insertion in infants and children. Further studies are needed to determine reliability of intraoperatively obtained cochlear view radiographs in this population.

Imaging Assessment of Complications from Transplantation from Pediatric to Adult Patients: Part 1: Solid Organ Transplantation.

End-stage organ failure is commonly treated with transplantation of the respective failing organ. Although outcomes have progressively improved over the decades, early and late complications do occur, and are often diagnosed by imaging. Given the increasing survival rates of transplant patients, the general radiologist may encounter these patients in the outpatient setting. Awareness of the normal radiologic findings after transplantation, and imaging findings of the more common complications, is therefore important. We review and illustrate the imaging assessment of complications from lung, liver, and renal transplantation, highlighting the key similarities and differences between pediatric and adult patients.

Imaging Assessment of Complications from Transplantation from Pediatric to Adult Patients: Part 2: Hematopoietic Stem Cell Transplantation.

Hematopoietic stem cell transplantation is an intravenous transfusion of pluripotent stem cells to repopulate the marrow and restore immunocompetence. However, before transplantation, the patient undergoes a conditioning regimen to eradicate the underlying disease, subsequently resulting in an immunocompromised state. Serious and some life-threatening complications involving any organ can occur. Currently, with advances in hematopoietic stem cell transplantation techniques and posttransplant management, more pediatric patients are now living longer and into their adulthood. The goal of this review article is to discuss the common neurologic, pulmonary, and abdominal complications associated with hematopoietic stem cell transplantation with emphasis on their imaging characteristics.

Dual-Energy CT of Pediatric Abdominal Oncology Imaging: Private Tour of New Applications of CT Technology.

OBJECTIVE. Dual-energy CT is gaining increasing recognition as a valuable diagnostic tool for assessing abdominal neoplasms. Nevertheless, much of the literature has focused on its use in adults. This review article illustrates specific tools available with dual-energy CT in the evaluation of pediatric abdominal neoplasms. Additionally, common imaging artifacts and pitfalls in dual-energy CT of the pediatric abdomen are outlined. CONCLUSION. Dual-energy CT can augment diagnostic yield in the imaging evaluation of pediatric abdominal neoplasms.

Pediatric Mediastinal Masses:: Role of MR Imaging as a Problem-Solving Tool.

Computed tomography (CT) is the imaging modality of choice for evaluating mediastinal masses detected by radiography or clinical presentation. However, CT results can often be indeterminate. Thoracic magnetic resonance (MR) imaging is a noninvasive way to characterize mediastinal lesions, site of origin, and involvement of adjacent structures by providing higher soft tissue contrast than CT, with superior tissue characterization and higher diagnostic specificity. Thoracic MR imaging of mediastinal masses can increase diagnostic certainty, reduce the number of surgical interventions, and improve clinical decision making. In this review article, current imaging techniques and clinical applications of MR imaging as a problem-solving tool for assessing mediastinal masses in pediatric patients are discussed.

Pediatric Renal Neoplasms:: MR Imaging-Based Practical Diagnostic Approach.

Pediatric renal tumors may be malignant or benign. Wilms tumor, the most common malignant pediatric renal tumor, arises sporadically or with various syndromes. Renal cell carcinoma typically presents in older children. Renal clear cell sarcoma and rhabdoid tumor are typically less common, more aggressive, and present in younger children. Benign renal tumors include mesoblastic nephroma, multilocular cystic renal tumor, angiomyolipoma, and metanephric adenoma. Lymphoma and leukemia may secondarily involve the kidney. Although there is overlap in the imaging appearance of several pediatric renal tumors, magnetic resonance characteristics and clinical data narrow the differential diagnosis and suggest a specific diagnosis. This article reviews current MR techniques, as well as the common MR imaging characteristics of malignant and benign pediatric renal neoplasms.

Aneurysmal dilation of bowel mimicking an abscess in pediatric primary gastrointestinal lymphoma.

Primary gastrointestinal lymphoma, though rare, is the most common gastrointestinal malignancy in children. Signs and symptoms are nonspecific, and include abdominal pain, nausea, emesis, and a palpable abdominal mass. Imaging is therefore typically required to differentiate gastrointestinal lymphoma from other abdominal conditions. We present a pediatric case of primary gastrointestinal lymphoma involving the distal bowel that was initially misdiagnosed as an intra-abdominal abscess. This case highlights the imaging findings of primary gastrointestinal lymphoma, potential pitfalls in imaging diagnosis, and the role of accurate imaging diagnosis in expediting patient management to reduce associated morbidity and mortality.

A hairy situation: trichobezoar presenting with intussusception, and intestinal and biliary perforation in a child.

Trichobezoars are an uncommon cause of acute abdominal pain. We present a case of a 12-year-old girl with a history of a trichobezoar who presented to the emergency department with acute abdominal pain. Abdominal sonography was performed which suggested portal venous gas and showed complex peritoneal fluid. Subsequent computed tomography demonstrated both gastric and small bowel bezoars, with a jejunojejunal intussusception, and confirmed portal venous gas and complex ascites. At the time of surgery, there was evidence of intestinal and biliary perforation. Our case illustrates a constellation of complications in association with a long-standing trichobezoar.

Pediatric Thoracic Organ Transplantation: Current Indications, Techniques, and Imaging Findings.

In the past decade, with improved surgical technique and knowledge of immunosuppression, pediatric lung and heart transplantation have been established as viable therapeutic interventions for pediatric patients with end-stage cardiopulmonary disease from various underlying congenital and acquired disorders. Although outcomes for pediatric patients are similar to those for adult patients, thoracic organ transplantation in this special age group carries unique challenges for preoperative and postoperative imaging evaluation. The article provides an up-to-date review of the postoperative transplant anatomy, imaging techniques, and complications of pediatric lung and heart transplantation.

Vertical expandable prosthetic titanium rib (VEPTR): a review of indications, normal radiographic appearance and complications.

Vertical expandable prosthetic titanium rib (VEPTR) is increasingly used in the treatment of thoracic insufficiency, idiopathic and neuromuscular scoliosis and chest wall defects in children. In contrast to spinal fusion surgery, the VEPTR allows for growth while stabilizing the deformity. We illustrate the common indications and normal radiographic appearance of the three common configurations of VEPTR (cradle-to-cradle assembly, cradle with lumbar extension assembly, cradle-to-ala hook assembly). There is a relatively high rate of reported complications with VEPTR in the literature. We discuss the potential complications of VEPTR, including infection, rib fracture, dislodged hardware and neurological injury, with an emphasis on imaging diagnosis.

Imaging of pediatric renal transplants and their complications: a pictorial review.

Renal transplantation is the treatment of choice for end-stage renal disease in children. As a technically demanding surgery with complex medical management, it is associated with a number of complications. Anatomic imaging including ultrasonography with color and spectral Doppler and functional assessment with renal perfusion scintigraphy are complementary for the detection and characterization of posttransplant complications. Complications can be characterized by the time of appearance after transplantation (immediate, early, or late) or the anatomic site of origin (perinephric, vascular, urologic, or renal parenchymal). Perinephric fluid collections include hematomas and seromas, abscesses, lymphoceles, and urinomas. Noninfected collections frequently resolve spontaneously but should be monitored to exclude progression. Vascular complications are more prevalent in pediatric patients because of the small vessel caliber and include vascular thrombosis and stenosis. Arteriovenous fistulas and pseudoaneurysms can complicate biopsy and are typically transient. Common urologic complications include urine leak and urinary tract obstruction. Renal perfusion scintigraphy can be invaluable in elucidating the nature of such complications. Renal parenchymal abnormalities include acute tubular necrosis, rejection, and toxic effects of medication. Imaging features of renal parenchymal abnormalities can overlap, and the primary role of imaging is to exclude alternative causes of renal dysfunction. Renal and nonrenal mass lesions are more common in immunosuppressed patients after transplantation. Familiarity with the normal imaging appearance of the renal allograft and the appearances of common complications facilitates accurate diagnosis and timely treatment, with the ultimate goal of increasing graft survival. This goal is particularly crucial in children, given their greater number of projected life years.

Pediatric chest CT radiation dose reduction: protocol refinement based on noise injection for pulmonary nodule detection accuracy.

To establish appropriate chest computed tomography (CT) acquisition protocols that balance radiation dose and diagnostic capability in pediatric bone marrow transplant patients by assessing the accuracy of pulmonary nodule detection at simulated lower-radiation acquisitions, chest CT images from bone marrow transplant patients were reviewed by four pediatric radiologists at artificially reduced CT dose levels (0%, 30%, and 60%). Average accuracy for nodule detection in 31 randomly selected cases was 0.87 at 0% dose reduction, 0.90 at 30% reduction, and 0.86 at 60% reduction. We observed no clinically relevant difference in acceptability of images or accuracy levels with tested dose reductions to 60%.

Interactive Web-based learning module on CT of the temporal bone: anatomy and pathology.

An interactive Web-based learning module on the temporal bone has been developed. It shows normal temporal bone anatomy in four imaging planes: axial, coronal, and parallel and perpendicular to the long axis of the petrous bone. After reviewing the normal anatomy, users should be able to identify key imaging features of pathologic conditions of the temporal bone. Children with congenital abnormalities of the temporal bone may present with conductive or sensorineural hearing loss or both and may have a genetic syndrome. Acute otitis media is the most common infection of the temporal bone and is most prevalent among children. Although imaging is unnecessary in uncomplicated otitis media, it is important for evaluation of infectious complications. Classically, temporal bone fractures were described as longitudinal or transverse with respect to the long axis of the petrous bone. However, it is increasingly recognized that many fractures have both longitudinal and transverse components. Patients with temporal bone fractures may have conductive or sensorineural hearing loss in addition to other complications. The most common tumor of the temporal bone at the cerebellopontine angle is the vestibular schwannoma. Paraganglioma is the second most common tumor of the temporal bone and the most common tumor of the middle ear. Supplemental material available at http://uwmsk.org/temporalbone/atlas.html.

Correlating Haller Index and cardiopulmonary disease in pectus excavatum.

BACKGROUND: The Haller Index (HI) has become standard for determining the severity of pectus excavatum. We compared patterns of cardiopulmonary dysfunction and their relationship with HI in patients with pectus excavatum. METHODS: We performed cardiopulmonary exercise testing and chest computed tomography scans on 90 patients with pectus excavatum deformities at a regional pediatric hospital. RESULTS: The median HI was 4.9 in patients with combined dysfunction, 4.4 in patients with isolated pulmonary dysfunction, 3.6 in patients with isolated cardiac dysfunction, and 3.4 in patients with normal function. HI varied significantly by disease group (P < .009). HI was significantly lower in patients with normal forced vital capacity than with abnormal forced vital capacity (P = .001). However, HI was similar in patients with normal and abnormal oxygen pulse (P = .24) or peak oxygen consumption (P = .37). CONCLUSIONS: Fifty-nine percent of patients had cardiac and/or pulmonary limitation. A HI greater than 3.6 is associated with pulmonary dysfunction, but not cardiac dysfunction.

Neonatal skeletal dysplasias.

Skeletal dysplasias are a large diverse group of disorders characterized by abnormal bone and cartilage growth. Approximately one-quarter of them are considered lethal in the perinatal period. This paper will review the components of the skeletal survey, the primary imaging tool for diagnosing dysplasias postnatally, emphasizing the use of an organized approach and appropriate descriptive terminology. Several illustrative cases of lethal and nonlethal dysplasias will be shown, with additional discussion of commonly associated genetic mutations and classification systems.

Usual and unusual causes of pediatric gastric outlet obstruction.

Gastric outlet obstruction in children encompasses a spectrum of disorders that extends beyond hypertrophic pyloric stenosis. Each condition can result in the clinical syndrome of persistent nonbilious vomiting, which can progress to dehydration and electrolyte imbalances. This paper reviews the spectrum of both the common and uncommon entities that cause partial or complete gastric outlet obstruction and their imaging appearances. The correct diagnosis of those with gastric outlet obstruction can be achieved by combining clinical presentation with appropriate imaging, leading to optimal and timely patient management.

Interactive, computer-based pediatric chest atlas.

OBJECTIVES: The authors created a computer-based, interactive atlas of pediatric chest radiographs to facilitate (1) understanding of normal variants and (2) interpretation of pediatric chest radiographs in the acute setting. METHODS: Seventy-three normal pediatric chest radiographs were selected for inclusion in the atlas by consensus after review by 3 pediatric radiologists. Sixteen abnormal pediatric chest radiographs showing a variety of abnormalities (infection, malignancy, congenital abnormalities, foreign body, and acquired disease), as well as 4 normal adult chest radiographs, were also included in the atlas. Images for the atlas were derived from Digital Imaging and Communications in Medicine-compliant data. The atlas software was written in C# and offers features of a picture archiving and communication system viewer. In addition, the atlas offers annotated series that describe particular radiographic features of normal variants and disease. RESULTS: The digital, interactive pediatric chest atlas displays normal chest radiographs of children aged 7 days to 17.8 years, as well as 4 normal adult chest radiographs and 16 abnormal pediatric chest radiographs. The digital interactive format of the atlas allows for (1) easy manipulation of atlas cases and (2) direct comparison between normal atlas cases and provided abnormal cases, as well as (3) the potential for direct comparison with images displayed on an institution's picture archiving and communication system. The atlas is available for free download at http://www.seattlechildrens.org/radiologyeducation/pediatric-chest. CONCLUSIONS: Improved interpretation of pediatric chest radiographs in the acute setting may be facilitated by a comprehensive, computer-based, pediatric chest atlas.