Obturator internus (OI) avulsion at its pelvic origin is an exceptionally rare cause of acute hip and groin pain in adolescents and is often radiographically occult. We report two adolescent boys with acute, severe hip pain and inability to ambulate after distinct mechanisms; one during a basketball jump without direct trauma and the other following a direct fall onto the hip. In both cases, pelvic and hip radiographs were normal. Magnetic resonance imaging established the diagnosis and revealed a strikingly similar constellation of findings in both patients: medial displacement and bowing of the OI away from the pelvic side wall with extensive muscle edema along its course extending through the sciatic notch, interposed fluid at the pelvic attachment, associated ipsilateral gluteus minimus edema, and a small-to-moderate hip effusion. Critically, a focal area of T1 hyperintensity deep to the displaced OI consistent with hemorrhage supported traumatic avulsion and helped distinguish this entity from infectious or inflammatory processes. Both patients were treated nonoperatively with protected weightbearing, activity modification, and physical therapy, with return to high activity at 1 year and 2.5 years. This report highlights a rare injury with a distinct and reproducible MR pattern that should alert radiologists and treating clinicians, enabling timely diagnosis and avoiding unnecessary investigations.

Suspected abdominal neoplasms in children encompass a wide range of malignant and benign tumors originating from various abdominal organs and structures. Neoplasms often present with a palpable abdominal mass, which may be accompanied by other symptoms such as abdominal pain, distension, or systemic signs. However, not all palpable masses in children represent neoplasms, as they may also result from benign conditions such as constipation or hernias. Imaging plays a vital role in differentiating these conditions. The role of imaging is to characterize the mass, identify the organ of origin, assess the extent of disease, and guide treatment decisions. This document provides imaging guidelines for children presenting with three clinical scenarios: palpable abdominal mass with suspected neoplasm at initial imaging, palpable abdominal mass with suspected neoplasm following negative radiography, and palpable abdominal wall mass with suspected abdominal wall neoplasm at initial imaging. 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 process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

For suspected physical abuse in infants and toddlers (<24 months), a radiographic skeletal survey and noncontrast head CT are usually appropriate first-line imaging, even if no injuries are apparent. These studies often reveal occult fractures or intracranial hemorrhages. For children >24 months without neurologic or visceral signs of injury, imaging is more targeted: radiographs of areas of concern are obtained, and skeletal surveys are used selectively, reflecting the lower yield of occult injuries in this older group. Neurologic symptoms or signs of head trauma warrant immediate neuroimaging; noncontrast head CT is the first-line acute study, with MRI reserved to further characterize brain injuries or subtle findings not seen on CT. For suspected visceral injury, contrast-enhanced abdominal CT is usually appropriate to detect internal injuries. A skeletal survey remains fundamental for detecting occult fractures in young children, and if initial studies are negative, a repeat skeletal survey after about 2 weeks is usually appropriate to identify healing injuries.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 process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Fever is the most common reason for the evaluation of pediatric patients in acute care settings. Patients for whom no source of infection is identified after a thorough history, physical examination, and laboratory evaluation are classified as having fever without source. Special considerations should be taken in the evaluation of neonates and neutropenic patients as they are at higher risk of serious bacterial infection. Patients with prolonged fever lasting >3 weeks who have no identifiable source of fever are classified with fever of unknown origin and represent an additional subset of febrile pediatric patients that also require special consideration. This document summarizes the relevant literature and provides expert recommendations for the selection of the initial imaging in four common clinical scenarios in pediatric patients with fever without source or unknown origin. 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 process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

OBJECTIVES:This practice parameter was developed collaboratively by the American College of Radiology (ACR), the American College of Nuclear Medicine (ACNM), the American Radium Society (ARS), the Society of Nuclear Medicine and Molecular Imaging (SNMMI), and the Society for Pediatric Radiology (SPR). This practice parameter is intended to guide appropriately trained and licensed physicians in the oral administration of I-131 sodium iodide for the treatment of benign and malignant thyroid diseases. METHODS:This practice parameter was revised according to the process described under the heading The Process for Developing ACR Practice Parameters and Technical Standards on the ACR website ( https://www.acr.org/Clinical-Resources/Practice-Parameters-and-Technical-Standards ) by the Committee on Practice Parameters-Nuclear Medicine and Molecular Imaging of the ACR Commissions on Nuclear Medicine and Molecular Imaging, the Committee on Practice Parameters-Radiation Oncology of the ACR Commission on Radiation Oncology, the Committee on Practice Parameters-Pediatric Radiology of the ACR Commission on Pediatric Radiology in collaboration with the ACNM, the ARS, the SNMMI, and the SPR. RESULTS:I-131 sodium iodide is used for the treatment of hyperthyroidism and differentiated thyroid cancer. The therapeutic effect of I-131 sodium iodide is achieved by the emission of ionizing radiation in the form of high-energy beta particles. I-131 sodium iodide therapy requires close cooperation and communication between the clinicians who are responsible for the clinical management of the patient and the physicians who administer radiopharmaceutical therapy. This document provides guidance regarding optimal therapy procedures, appropriate precautions, and therapy in unique situations. CONCLUSIONS:This practice parameter is designed to assist practitioners in providing appropriate radiologic care for treating benign and malignant thyroid disease with I-131 sodium iodide.

Soft tissue vascular anomalies may be composed of arterial, venous, and/or lymphatic elements, and diagnosed prenatally or later in childhood or adulthood. They are divided into categories of vascular malformations and vascular tumors. Vascular malformations are further divided into low-flow and fast-flow lesions. A low-flow lesion is most common, with a prevalence of 70%. Vascular tumors may behave in a benign, locally aggressive, borderline, or malignant manner. Infantile hemangioma is a vascular tumor that presents in the neonatal period and then regresses. The presence or multiple skin lesions in an infant can signal underlying visceral vascular anomalies, and complex anomalies may be associated with overgrowth syndromes.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 process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Urinary tract infection (UTI) is a frequent infection in childhood. The diagnosis is usually made by history and physical examination and confirmed by urine analysis. Cystitis is infection or inflammation confined to the bladder, whereas pyelonephritis is infection or inflammation of kidneys. Pyelonephritis can cause renal scarring, which is the most severe long-term sequela of UTI and can lead to accelerated nephrosclerosis, leading to hypertension and chronic renal failure. The role of imaging is to guide treatment by identifying patients who are at high risk to develop recurrent UTIs or renal scarring. This document provides initial imaging guidelines for children presenting with first febrile UTI with appropriate response to medical management, atypical or recurrent febrile UTI, and follow-up imaging for children with established vesicoureteral reflux.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 process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

A newborn with congenital segmental dilatation of the intestine affecting the colon is presented. This rare condition, unrelated to Hirschsprung's disease, may affect any portion of the bowel and is characterized by focal dilatation of a segment of bowel flanked by normal proximal and distal bowel. While reported in the surgical literature, congenital segmental dilatation of the intestine has not been reported in the pediatric radiology literature even though pediatric radiologists may be the first to encounter imaging suggesting the diagnosis. We therefore present the characteristic imaging findings, including abdominal radiographs and images from a contrast enema, and discuss the clinical presentation, pathology findings, associations, treatment, and prognosis of congenital segmental dilatation of the intestine to increase awareness of this unusual diagnosis.

BACKGROUND:COVID-19 is associated with pulmonary embolism (PE) in adults. However, the rate of PE in pediatric patients with acute COVID-19 evaluated by CT pulmonary angiography (CTPA) has not been evaluated. OBJECTIVE:Determine PE rate in pediatric patients with acute COVID-19 and compare to adults. MATERIALS AND METHODS:A retrospective review of CTPA studies, performed between March 2020 and January 2021 on pediatric patients with acute COVID-19, but not MIS-C, was performed. CTPAs performed on an adult cohort of acute COVID-19 patients during April 2020 were reviewed for comparison. Pediatric and chest radiologists independently reviewed CTPAs of pediatric and adult patients, respectively. RESULTS:Of the 355 acute COVID-19 pediatric patients treated during the study period, 14 (16.6 ± 4.8y, median-18.5y, 64% female) underwent CTPA. Of the 1868 acute COVID-19 adults treated during two weeks in April 2020, 50 (57.2 ± 17.0y, median-57.0y, 42% female) underwent CTPA. The PE rate was 14% in the pediatric group (2 patients) and 18% in the adult group (9 patients) (p = 1.0). Both pediatric patients with PE were obese, over 18y, and had asthma, diabetes mellitus, or hypertension. No child<18y with acute COVID-19 had PE. In the adult cohort, higher alanine-aminotransferase and D-dimer levels were associated with PE (p = 0.04 and p = 0.004, respectively). CONCLUSION:Despite similar PE rates in pediatric and adult patients, PE occurred in acute COVID-19 pediatric patients who were >18y, obese, and had at least 1 comorbidity. Children <18y with COVID-19 did not have PE.

The two primary manifestations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in children are acute coronavirus disease 2019 (COVID-19) pneumonia and multisystem inflammatory syndrome (MIS-C). While most pediatric cases of acute COVID-19 disease are mild or asymptomatic, some children are at risk for developing severe pneumonia. In MIS-C, children present a few weeks after SARS-CoV-2 exposure with a febrile illness that can rapidly progress to shock and multiorgan dysfunction. In both diseases, the clinical and laboratory findings can be nonspecific and present a diagnostic challenge. Thoracic imaging is commonly obtained to assist with initial workup, assessment of disease progression, and guidance of therapy. This paper reviews the radiologic findings of acute COVID-19 pneumonia and MIS-C, highlights the key distinctions between the entities, and summarizes our understanding of the role of imaging in managing SARS-CoV-2-related illness in children.

The role of MRI in evaluating children with an in situ gallbladder and suspected choledocholithiasis following a negative or inconclusive US is unclear. To determine whether MRI benefits children with suspected choledocholithiasis and a normal common bile duct (CBD) without stones on US. We conducted a retrospective 10-year review of paired US and MRI (within 10 days) in children 18 years or younger with suspected choledocholithiasis. With MRI as a reference standard, two reviewers independently evaluated the images for CBD diameter, choledocholithiasis, cholelithiasis and pancreatic edema. Serum lipase was recorded. We calculated exact binomial confidence limits for test positive predictive values (PPVs) and negative predictive values (NPVs) using R library epiR. Of 87 patients (46 female, 41 male; mean age 14 years, standard deviation [SD] 4.6 years; mean interval between US and MRI 1.6 days, SD 1.8 days), 55

Imaging plays an integral role in the evaluation of suspected musculoskeletal infections in children, not only in the accurate identification of infection such as osteomyelitis or septic arthritis, but also in guiding management. Various diagnostic modalities serve different purposes in the assessment of suspected pediatric musculoskeletal infections. The purpose of this document is to provide imaging guidance in the most frequently encountered clinical scenarios in which osteomyelitis and/or septic arthritis are suspected, outside of the axial skeleton. 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.

Journal of Ultrasound in MedicineVolume 41, Issue 4 p. E9-E15 Practice ParameterFree Access The AIUM Practice Parameter for the Performance of an Ultrasound Examination of the Neonatal and Infant Spine First published: 18 November 2021 https://doi.org/10.1002/jum.15875AboutSectionsPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Introduction The American Institute of Ultrasound in Medicine (AIUM) is a multidisciplinary association dedicated to advancing the safe and effective use of ultrasound in medicine through professional and public education, research, development of clinical practice parameters, and accreditation of practices performing ultrasound examinations. The AIUM Practice Parameter for the Performance of an Ultrasound Examination of the Neonatal and Infant Spine was revised by the AIUM in collaboration with other organizations whose members use ultrasound for performing this examination (see “Acknowledgments”). Recommendations for personnel requirements, the request for the examination, documentation, quality assurance, and safety may vary among the organizations and may be addressed by each separately. This practice parameter is intended to provide the medical ultrasound community with recommendations for the performance and recording of high-quality ultrasound examinations. The parameters reflect what the AIUM considers the appropriate criteria for this type of ultrasound examination but is not intended to establish a legal standard of care. Examinations performed in this specialty area are expected to follow the parameter with the recognition that deviations may occur depending on the clinical situation. Indications The indications for ultrasonography of the neonatal/infant spinal canal and its contents include, but are not limited to1-13: Lumbosacral stigmata known to be associated with spinal dysraphism and tethered spinal cord, including: Midline or paramedian masses Midline skin discolorations Skin tags Hair tufts Hemangiomas Atypical sacral dimples (high risk; see below) The spectrum of caudal regression syndrome, including patients with sacral agenesis or anorectal malformations such as Currarino Triad, VACTERL association, Cloaca, and OEIS complex Evaluation of suspected spinal cord abnormalities such as cord tethering, diastematomyelia, hydromyelia, or syringomyelia Detection of acquired abnormalities and complications such as: Hematoma following injury Infection or hemorrhage secondary to prior instrumentation, such as lumbar puncture Posttraumatic leakage of cerebrospinal fluid (CSF) Misplacement of devices and lines Visualization of blood products within the spinal canal in patients with intracranial hemorrhage Guidance for lumbar puncture11, 12 Postoperative assessment for recurrence of cord tethering14 Evaluation for congenital spine tumors, for example, sacrococcygeal teratoma Please note that there are some indications for ultrasonography of the spine and spinal canal in children outside the neonatal or infant period. The technique for these studies is beyond the scope of this practice parameter but is described in the literature. These indications include, but are not limited to, intraoperative guidance for tumor resection, decompression of Chiari I malformation, and catheter placement for neuraxial analgesia,15, 16 neurostimulator device placement and monitoring its positioning, and assessment of lengthening of magnetically controlled growing spinal rods.17 Sacral dimples associated with a high risk of occult spinal dysraphism include those in which the base of the dimple is not seen, are located >2.5 cm above the anus, or are seen in combination with other cutaneous abnormalities.3 The examination has a low diagnostic yield in infants with simple, low-lying coccygeal dimples; such patients typically have normal spinal contents.3, 7, 13, 15 Ultrasound is not considered essential in the workup of simple sacral dimples. Contraindications Preoperative examination of an open spinal dysraphic defect. However, in such cases, the closed portion of the spinal canal away from the open defect can be examined for other suspected abnormalities, such as syrinx or diastematomyelia. These latter abnormalities should be identified preoperatively. Examination of the contents of a closed neural tube defect, if the skin overlying the defect is thin or no longer intact Qualifications and Responsibilities of Personnel Physicians interpreting or performing this type of ultrasound examination should meet the specified AIUM training guidelines in accordance with AIUM accreditation policies. Sonographers performing the ultrasound examination should be appropriately credentialed in the specialty area in accordance with AIUM accreditation policies. Physicians not personally performing the examination must provide supervision, as defined by the Centers for Medicare and Medicaid Services Code of Federal Regulations 42 CFR §410.32. Request for the Examination The written or electronic request for an ultrasound examination must originate from a physician or other appropriately licensed health care provider or under the provider's direction. The clinical information provided should allow for the performance and interpretation of the appropriate ultrasound examination and should be consistent with relevant legal and local health care facility requirements. Specifications of the Examination The examination is usually performed with the patient lying in the prone position, although the study can also be done with the patient lying on their side. When necessary, upright or prone reversed Trendelenburg positioning with resultant CSF distention of the lower thecal sac may permit better delineation of the cauda equina. A small bolster may be placed under the lower abdomen or pelvis to mildly flex the back, which may improve imaging. The knees may be flexed to the abdomen to allow adequate separation of the spinous processes and visualization of the spinal canal contents. Avoid overzealous and excessive flexing that could impede respiration.18 An infant who has recently been fed will generally lie quietly during the examination. If preprocedural feeding is not possible, a pacifier dipped in glucose solution can be helpful in keeping an infant still, thereby optimizing the examination. The infant may be also positioned in the caregiver's lap, which may have a calming effect, decreasing motion. Positioning the infant semierect also allows for accumulation of CSF in the lower thecal sac, which widens the interlaminar spaces and creates a better acoustic window. Furthermore, this gravitational CSF distention may increase detection of any existing lumbosacral meningoceles.17 It is important to note that infants, particularly if not full-term, have difficulty maintaining normal body temperature. The baby should be kept warm enough to maintain normal body temperature during the procedure, and the coupling agent should be warmed. The spinal cord should be assessed in longitudinal and transverse planes, with right and left labeled on transverse images. Longitudinal images are ideally obtained in the midline sagittal plane, although in larger or older babies (with greater spine ossification), it may be necessary to obtain images in a slightly off-midline parasagittal plane that is parallel to the spinous processes. Studies are typically limited to the lumbosacral and lower thoracic region as in patients being evaluated for a sacrococcygeal dimple and tethered cord, or when searching for the presence of hematoma after an unsuccessful or traumatic spinal tap. However, the entire spinal canal, from the craniocervical junction to the coccyx, may be included in the examination. Normal cord morphology and the level of termination of the conus medullaris should be assessed and documented, which requires accurate identification of vertebral body level. The conus normally lies at or above the L2 to L3 disc space.9, 19-22 A normal conus located as low as the mid-L3 level may be identified, especially in preterm infants22; this position may be considered the lower limits of normal and is usually without clinical consequence.23 However, in a preterm infant with a conus that terminates in the region of the L3 midvertebral body, a follow-up ultrasound can be obtained once the infant attains a corrected age between 40 weeks gestation and 4 months of age to document a rise in conus level.8 The morphology of the conus should be documented as well as any deviation from normal, such as blunting of the tip. Vertebral body level of the end of the spinal cord can be determined in a number of ways.24, 25 These include: Assessment of the normal lumbosacral curvature to locate the lumbosacral junction and thus the location of L5. The vertebral level of the conus medullaris is then determined by counting cephalad from L5. Lumbar vertebral bodies typically lie in a horizontal plane in a prone infant, whereas the sacral vertebral bodies lie at an angle similar to what is seen on lateral radiographs of the lumbosacral spine. This counting method tends to be more reproducible than the other methods described below. Extended field-of-view (panoramic) imaging can often aid in identification of a longer segment of the spine and facilitate identification of the vertebral level, particularly the L5-S1 level. Lumbar spine flexion-extension maneuvers might also allow easier identification of the lumbosacral junction. The first coccygeal segment has variable ossification at birth. If ossified, it can be distinguished by its rounder or more triangular shape compared with the square or rectangular shape of the sacral bodies. Counting cephalad from the fifth sacral ossification center can help determine the vertebral level of the conus. The thecal sac usually ends at S2.26 This level can then be used to count cephalad to determine the location of the conus. The last rib-bearing vertebra can be presumed to be T12, and the lumbar level of the conus can then be determined, although this is less reliable because of the variability in the number of ribs. When the level of the conus cannot be definitively assessed as normal or abnormal, correlation with previous plain films, if available, is helpful. A radiopaque marker can be placed on the skin at the level of the conus determined by sonographic guidance, followed by a correlative anteroposterior spine radiograph. In addition to the level and location of the cord, motion of the nerve roots is another important parameter in assessment for cord tethering. The cord is normally positioned dependently or centrally within the spinal canal, and any deviation from normal (eg, apposition to the dorsal aspect of the spinal canal) should be documented. Transverse images are extremely helpful to demonstrate a dependent position of the cord. Cine images should be recorded and archived as an aid in demonstrating anatomy and particularly in showing movement of the distal cord and nerve roots in conjunction with normal pulsations of the spinal CSF. The normal nerve roots typically oscillate freely with cardiac and respiratory motion, layer dependently with variable patient positioning, and are not adherent to each other. Cine images can also document changes that occur with head flexion and extension. M-mode ultrasound can also be helpful in documenting motion of the cord and nerve roots. In newborns, diminished or absent motion of the conus and cauda equina due to decreased subarachnoid fluid related to the normal dehydration status has been reported. In these instances, follow-up spine ultrasound may be warranted.27 Areas of abnormal fluid accumulation within the spinal cord and spinal canal should be documented with their level identified, such as hydromyelia or syringomyelia; anterior, lateral, or posterior meningoceles or pseudomeningoceles; and arachnoid cysts. Transverse images are essential to identify and document diastematomyelia. Off-center scanning may avoid the refraction artifact that creates an apparent lateral cord duplication, or ghost image that resembles diastematomyelia.28-30 The subarachnoid space is normally anechoic in appearance, interrupted by normal hyperechoic linear nerve roots and dentate ligaments. The subarachnoid space, dura, and epidural space should be evaluated for abnormalities such as hematoma, lipoma, or other masses. In addition to the termination of the conus, the termination of the thecal sac, typically located at S2, should be documented.26 The filum terminale and its thickness should be noted; the filum is normally <2 mm thick,31 although recent studies have suggested a lower cutoff value of 1.1 mm.32 Increased echogenicity and thickening of the filum may indicate a fatty filum. Upright positioning can be used for image guidance of lumbar puncture or to demonstrate meningoceles or pseudomeningoceles. Anterior meningoceles or presacral masses can also be scanned from an anterior position, usually through a fluid-filled bladder. The vertebral bodies and posterior elements can be evaluated for deformities. Open posterior elements in skin-covered dysraphic defects can be documented on transverse views. Tracts extending from the skin surface should be assessed for connection to the spinal canal. A standoff pad or a thick layer of coupling gel may be used, if needed, to evaluate the superficial soft tissues and skin line for the presence of a tract. Documentation Accurate and complete documentation is essential for high-quality patient care. Written reports and ultrasound images/video clips that contain diagnostic information should be obtained and archived, with recommendations for follow-up studies if clinically applicable, in accordance with the AIUM Practice Parameter for Documentation of an Ultrasound Examination. The initials of the operator should be accessible on the images or electronically in the electronic medical record (eg, PACS or radiology information software). Equipment Specification Equipment performance monitoring should be in accordance with the AIUM Routine Quality Assurance of Clinical Ultrasound Equipment, Version 2.0.33 Ultrasound of the infant spine should be performed with real-time scanners using high-frequency linear array transducers, typically ranging from 9 to 12 MHz or higher in neonates.34 In larger babies, it may be necessary to utilize a lower-frequency probe ranging from 5 to 9 MHz. A curvilinear probe ranging from 3 to 9 MHz may be needed if a larger field of view is desired or the acoustic access is limited, as in older infants. Panoramic views of the entire spinal canal are very helpful in providing an overview of the anatomy by displaying a more global image of the relationship of the spinal cord with the vertebral column and determining the level of the conus medullaris. The use of a split-screen or dual-function technique is similarly useful for obtaining a longer longitudinal image of the cord and spinal column. Images of the craniocervical junction can be obtained with a small vector or curved transducer to accommodate the curvature of the cervical spine. Clinical protocols should be reviewed to optimize image quality while reducing possible risks due to thermal and mechanical effects. Quality and Safety Policies and procedures related to quality assurance and improvement, safety, infection control, and equipment performance monitoring should be developed and implemented in accordance with the AIUM Standards and Guidelines for the Accreditation of Ultrasound Practices. ALARA (As Low as Reasonably Achievable) Principle The potential benefits and risks of each examination should be considered. The ALARA principle should be observed for factors that affect the acoustical output and by considering transducer dwell time and total scanning time. Further details on ALARA may be found in the current AIUM publication Medical Ultrasound Safety. Infection Control Transducer preparation, cleaning, and disinfection should follow manufacturer recommendations and be consistent with the AIUM Guidelines for Cleaning and Preparing External- and Internal-Use Ultrasound Transducers Between Patients, Safe Handling, and Use of Ultrasound Coupling Gel. Equipment Performance Monitoring Monitoring protocols for equipment performance should be developed and implemented in accordance with the AIUM Standards and Guidelines for the Accreditation of Ultrasound Practice. Acknowledgments This parameter was developed by the AIUM in collaboration with the American College of Radiology (ACR), the Society for Pediatric Radiology (SPR), and the Society of Radiologists in Ultrasound (SRU). We are indebted to the many volunteers who contributed their time, knowledge, and energy to developing this document. Collaborative Subcommittees AIUM Susan J. Back, MD Nadia F. Mahmood, MD Mariana Meyers, MD, FAIUM ACR Jane Sun Kim, MD, Co-Chair Erica Poletto, MD, Co-Chair Harriet J. Paltiel, MD, FAIUM Henrietta K. Rosenberg, MD, FACR Judy H. Squires, MD SPR Paul Clark, DO Harris L. Cohen, MD, FACR, FAIUM, FSRU Monica Epelman, MD SRU Lynn A. Fordham, MD, FACR, FAIUM, FAAWR Comment Reconciliation Committee Richard Gunderman, MD, FACR, Chair Timothy Crummy, MD, FACR, Co-Chair Susan J. Back, MD Richard A. Barth, MD, FACR Paul Clark, DO Harris L. Cohen, MD, FACR, FAIUM, FSRU Richard Duszak Jr., MD, FACR Samuel A. Einstein, PhD Monica Epelman, MD Lynn A. Fordham, MD, FACR, FAIUM, FAAWR Lauren P. Golding, MD Jane Sun Kim, MD Amy Kotsenas, MD, FACR David B. Larson, MD, MBA Paul A. Larson, MD, FACR Terry L. Levin, MD, FACR Nadia F. Mahmood, MD Mariana Meyers, MD, FAIUM Mary S. Newell, MD, FACR Harriet J. Paltiel, MD, FAIUM Erica Poletto, MD Margarita Revzin, MD, FAIUM Henrietta K. Rosenberg, MD, FACR Michael Ian Rothman, MD, FACR Ramon Sanchez-Jacob, MD Sheila Sheth, MD, FACR James Shwayder, MD, FAIUM Cicero Silva, MD Judy H. Squires, MD Richard B. Towbin, MD, FACR AIUM Clinical Standards Committee James M. Shwayder, MD, JD, FAIUM, chair Rachel Bo-ming Liu, MD, FAIUM, vice chair Bryann Bromley, MD, FAIUM Nirvikar Dahiya, MD, FAIUM Rob Goodman, MBBCh, MBA, BMSc Margarita Revzin, MD, FAIUM Jean Spitz, MPH, CAE, RDMS, FAIUM John Stephen Pellerito, MD, FAIUM Original copyright 2007; Revised 2021, 2016, 2011; Renamed 2015 References 1Guggisberg D, Hadj-Rabia S, Viney C, et al. Skin markers of occult spinal dysraphism in children: a review of 54 cases. Arch Dermatol 2004; 140: 1109– 1115. 2Izci Y, Gonul M, Gonul E. The diagnostic value of skin lesions in split cord malformations. J Clin Neurosci 2007; 14: 860– 863. 3Kriss VM, Desai NS. Occult spinal dysraphism in neonates: assessment of high-risk cutaneous stigmata on sonography. 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Crohn disease is an inflammatory condition of the gastrointestinal tract with episodes of exacerbation and remission occurring in children, adolescents, and adults. Crohn disease diagnosis and treatment depend upon a combination of clinical, laboratory, endoscopic, histological, and imaging findings. Appropriate use of imaging provides critical information in the settings of diagnosis, assessment of acute symptoms, disease surveillance, and therapy monitoring. Four variants are discussed. The first variant discusses the initial imaging for suspected Crohn disease before established diagnosis. The second variant pertains to appropriateness of imaging modalities during suspected acute exacerbation. The third variant is a substantial discussion of recommendations related to disease surveillance and monitoring of Crohn disease. Finally, panel recommendations and discussion of perianal fistulizing disease imaging completes the document. 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.

A portable radiographic system capable of fluoroscopic imaging in the neonatal intensive care unit (NICU) potentially benefits critically ill neonates by eliminating the need to transport them to a fluoroscopy suite. To evaluate whether a portable bedside fluoroscopy system in the NICU can deliver comparable image quality at a similar dose rate to a standard system in a fluoroscopy suite. In phase A, 20 patients <3 years of age and scheduled to undergo upper gastrointestinal series (upper GI) or voiding cystourethrograms (VCUG) in the radiology fluoroscopy suite were recruited to evaluate a portable fluoroscopic unit. A modified portable radiographic system with a cassette-sized detector and an in-room fluoroscopy system were sequentially used in the same examination. Four radiologists compared the image quality of 20 images from each system using the Radlex score (1–4) for five image quality attributes. The radiation dose rates for the portable and in-suite systems were collected. In phase B, fluoroscopy studies were performed in 5 neonates in the NICU and compared to the 20 previous neonatal studies performed in the department. Clinical workflow, examination time, fluoroscopy time, scattered radiation dose and patient radiation dose were evaluated. In phase A, average dose rates for in-room and portable systems were equivalent, (0.322 mGy/min and 0.320 mGy/min, respectively). Reader-averaged Radlex scores for in-room and portable systems were statistically significantly greater (P<0.05) for all attributes on the portable system except for image contrast. In phase B, scattered radiation from the average fluoroscopy time (26 s) was equivalent to the scattered radiation of 2.6 portable neonatal chest radiographs. Procedure time and diagnostic quality were deemed equivalent. The average dose rate in the NICU with the portable system was 0.21 mGy/min compared to 0.29 mGy/min for the in-room system. The portable fluoroscopy unit is capable of providing comparable image quality at equivalent dose levels to an in-room system for neonates with minimal risks to the staff and other patients in the NICU.

Objectives: The relationship between vitamin D deficiency (VDD) and pediatric nonalcoholic fatty liver disease (NAFLD) remains uncertain due to conflicting results and few studies with histologic endpoints. We therefore used multiple imaging and histologic NAFLD endpoints to more comprehensively assess the association between VDD and NAFLD in a large pediatric population. Methods: Data were obtained from an ongoing pediatric NAFLD study in Bronx, NY. Briefly, overweight and obese children aged 2 to 18 years with alanine aminotransferase levels ≥35 U/L were serially enrolled. Liver biopsy was obtained in accordance with clinical guidelines. All participants had liver imaging, namely, controlled attenuation parameter to assess steatosis and, to assess fibrosis, vibration controlled transient elastography (FibroScan), and acoustic radiation force impulse imaging. Levels of 25-hydroxyvitamin D were measured serologically. Results: N = 276 (88%) of 315 participants had 25-OH vitamin D results, of whom 241 (87%) were Hispanic, 199 (72%) were male, and 92 (33%) underwent liver biopsy. VDD was univariately associated with high waist circumference (P = 0.004), high-density lipoprotein level (P = 0.01), season (P = 0.009), and controlled attenuation parameter score (P = 0.01). In multivariate analysis, only waist circumference (P = .0002) and biopsy inflammation grade (P = 0.03) were associated with VDD, though the latter had not approximated statistical significance in univariate analysis (P = 0.56). There was no association between VDD and hepatic steatosis, ballooning, NAFLD activity score, and acoustic radiation force impulse or vibration controlled transient elastography elasticity scores. Conclusions: VDD was not associated with NAFLD defined by imaging and histologic endpoints, except for a possible relation with histologic inflammation grade.