Gary R. Schooler

Pediatric whole-body MRI: A review of current imaging techniques and clinical applications.

There are many congenital, neoplastic, inflammatory, and infectious processes in the pediatric patient for which whole‐body imaging may be of benefit diagnostically and prognostically. With recent improvements in magnetic resonance imaging (MRI) hardware and software and resultant dramatically reduced scan times, imaging of the whole body with MRI has become a much more practicable technique in children. Whole‐body MRI can provide a high level of soft tissue and skeletal detail while avoiding the exposure to ionizing radiation inherent to computed tomography and nuclear medicine imaging techniques. This article reviews the more common current whole‐body MRI techniques in children and the primary pathologies for which this imaging modality may be most useful to the radiologists and referring clinicians. J. MAGN. RESON. IMAGING 2016;44:783–793.

Developmental lung malformations in children: recent advances in imaging techniques, classification system, and imaging findings.

Congenital lung anomalies represent a diverse group of developmental malformations of the lung parenchyma, arterial supply, and venous drainage, which may present anywhere from the prenatal period through adulthood. It is imperative for radiologists to be aware of imaging techniques and imaging appearance of these anomalies across the pediatric age range. This review presents the spectrum of these lesions that are often encountered in daily clinical practice. Each anomaly is discussed in terms of underlying etiology, clinical presentation, and imaging characterization with emphasis on the most up-to-date research and treatment. Knowledge of these areas is essential for accurate, timely diagnosis, which aids in optimizing patient outcomes.

Evaluation of Contrast Injection Site Effectiveness: Thoracic CT Angiography in Children With Hand Injection of IV Contrast Material

OBJECTIVE. The purpose of this study was to evaluate the effectiveness of various contrast injection sites when performing thoracic CT angiography (CTA) using hand injection of IV contrast material in infants and young children with a small IV catheter. MATERIALS AND METHODS. We used our hospital information system to retrospectively identify consecutive pediatric patients who underwent thoracic CTA with hand injection of contrast material from August 2012 to July 2013. The study indication for thoracic CTA was to evaluate the thoracic systemic arterial vasculature and pulmonary venous vasculature. Both qualitative and quantitative evaluation of thoracic CTA image quality was performed by two reviewers independently. Qualitative evaluation of thoracic CTA image quality was performed by visual assessment of the degree of contrast enhancement in the ROI on a 4-point scale. Quantitative evaluation was performed by measuring attenuation obtained with the ROI placed within the aorta at two locations (the level of the aortic arch and at the level of the carina) to evaluate the thoracic systemic arterial vasculature. For evaluation of the pulmonary venous system, attenuation measurements were obtained at the center of the left atrium. Six individual injection sites were identified: head, jugular vein, arm vein, hand vein, leg vein, and foot vein. Injection sites were categorized into three regional groups: head-neck region (head vein and jugular veins), upper extremity region (arm and hand veins), and lower extremity region (leg and foot veins). Comparisons of attenuation values between individual and regionally grouped contrast injection sites were determined using the F-test in ANOVA. RESULTS. The study cohort included 50 pediatric patients (29 boys and 21 girls; mean age, 8 months ± 1 year; range, 1 week to 5 years) who underwent a total of 50 thoracic CTA studies for evaluating the thoracic systemic arterial vasculature (n = 38; 76%) or pulmonary venous vasculature (n = 12; 34%). All 50 thoracic CTA studies were of diagnostic quality on the basis of qualitative evaluation (all ≥ 3). For quantitative evaluation with the threshold for a diagnostic thoracic CTA study defined as attenuation greater than 150 HU in the ROI, all 50 thoracic CTA studies were technically successful (aortic arch, 380 ± 150 HU; descending thoracic aorta at the level of the carina, 392 ± 155 HU; and left atrium, 352 ± 90 HU). There were no significant differences in mean attenuation between individual injection sites (p > 0.20 for each comparison) or different regional groups (p > 0.50 for each comparison). CONCLUSION. Diagnostic quality thoracic CTA can be achieved with hand injection of IV contrast material in infants and young children with a small IV catheter, independent of the IV access site.

Diagnostic errors of right lower quadrant pain in children: beyond appendicitis

Abstract Right lower quadrant pain in children can result from various underlying conditions other than acute appendicitis. The common mimics of acute appendicitis are related to acute gastrointestinal and genitourinary diseases. Diagnosis of right lower quadrant pain in the pediatric population can be challenging, especially when the symptoms are often nonspecific. This article reviews the currently available imaging techniques for evaluating a child with right lower quadrant pain and the spectrum of differential diagnoses with a focus on imaging clues to a specific diagnosis.

The Current State of Radiology Call Assistant Triage Programs Among US Radiology Residency Programs

RATIONALE AND OBJECTIVES Given increasing volume and workflow interruptions in radiology, we sought to identify and characterize radiology call assistant triage (RCAT) programs among US radiology residency programs. MATERIALS AND METHODS A survey was created using Qualtrics survey software and emailed to all members of the Association of Program Directors in Radiology listserv. A total of 296 active members belong to this listserv, including program directors and assistant program directors. The survey included questions about the existence and specifics of a call triage assistant program. RESULTS Data were obtained from 88 active members of the Association of Program Directors in Radiology (30% response rate). Of those, 20 programs (23%) have an RCAT program. Triage assistant staffing includes nonmedical or clerical staff (60%), medical students (30%), first-year radiology residents (5%), and technologists (5%). All respondents with RCAT programs report satisfaction with their program and plan to continue. A significant majority (75%) have no plans to change, whereas the remaining 25% are considering program expansion and pay increases. Among residency programs without RCAT programs, none reported termination of their triage program. The most common reasons for not having triage assistants include cost, lack of awareness, differing opinions on utility, and the presence of 24/7 attending coverage. CONCLUSION Twenty US radiology residency programs report having an RCAT program. All report satisfaction with their program despite different staffing models. RCAT programs may represent an effective measure in limiting interruptions and potentially decreasing interpretative errors made by residents on call.

Cystic biliary atresia: A distinct clinical entity that may mimic choledochal cyst

Cystic biliary atresia (CBA) is a relatively uncommon but clinically significant variant of biliary atresia. The presence of a cyst in the hepatic hilum on imaging in an infant with cholestasis supports the diagnosis of CBA, but can also be seen in patients with a choledochal cyst—the main differential diagnosis in patients with CBA. The reported case outlines the clinical presentation and imaging findings in a patient with surgically confirmed and treated CBA and emphasizes the importance of distinguishing CBA from choledochal cyst at diagnostic imaging given the disparate timing and type of surgical treatment necessary for successful management of these distinct entities.

Correction to: Chest computed tomography angiography in children on extracorporeal membrane oxygenation (ECMO)

The published version of this article incorrectly lists the authors’ affiliations. The correct affiliations are given below. The Publisher regrets this mistake.

Chest computed tomography angiography in children on extracorporeal membrane oxygenation (ECMO)

Performing chest CT angiography on pediatric patients on extracorporeal membrane oxygenation (ECMO) can be challenging. Successfully performing CT angiography in these children requires substantial communication and coordination between the radiologists and clinical care providers. Additionally, the radiologist must understand the child’s anatomy and disease pathophysiology, flow dynamics of the ECMO circuit, image acquisition timing, contrast injection site, and volume, rate and duration of contrast administration. In this article we highlight the vital factors the radiologist needs to consider to optimize the chest CT angiography in pediatric patients on ECMO.

Variability in billing practices for whole-body magnetic resonance imaging: reply to Degnan et al.

Dear Editors, We would like to thank Degnan and colleagues [1] for their insightful comments regarding our recent article on utilization and procedural practices in pediatric whole-body MRI. As was stated in our article and expanded upon by Degnan and colleagues, billing practices are variable for pediatric wholebody MRI [2]. The lack of dedicated Current Procedural Terminology (CPT) codes for whole-body MRI permits this variability, exacerbates billing challenges, and may ultimately lead to patient care challenges. As an imaging community, we should work toward a cohesive definition of what encompasses a whole-body MRI examination in the pediatric patient population. Our article revealed the amount of variability that exists in what body parts are included in an exam that is labeled as a wholebody MRI [1]. An initial task in creating a whole-body MRI procedure-specific code is to define what parts of the body must be imaged to constitute a “whole-body” MRI. While standardization of coverage is necessary, formulating a requisite standardized set of sequences for pediatric whole-body MRI is impractical because of the need to account for patient-, providerand institution-specific variables. Rather, guidelines for best practices (including sequence selection and plane of imaging) could be delivered via an entity such as the American College of Radiology Appropriateness Criteria. Such appropriateness criteria could provide valuable guidance and further definition. Whole-body MRI is a valuable imaging tool in pediatric patients that must continue to be further defined. Ultimately, determining the constituent body parts, establishing guidelines for best practices, and creating procedure-specific billing codes will all help improve pediatric whole-body MRI.

Favorable response to nivolumab in a young adult patient with metastatic histiocytic sarcoma

To the Editor: Histiocytic sarcoma (HS) is a rare hematopoietic neoplasm consisting of a malignant proliferation of cells that resembles mature tissue histiocytes.1 Prognosis for HS is poor; a recent survey of the Surveillance, Epidemiology, and End Results (SEER) database demonstrated a median overall survival of 6 months among a cohort of 158 patients.2 There is not a universally accepted treatment for HS, though responses have been seenwith chemotherapy, surgery, or radiation therapy.3,4 Recent reports have demonstrated a high rate of PDL1 expression in histiocytic disorders, suggesting a potential therapeutic target.5,6 Here we report a case of HS in a young adult patient who had a favorable response to nivolumab. A 17-year-old female presented to her primary care provider with intermittent left upper leg pain, fatigue, fevers, unintentional weight loss, and swollen lymphnodes. Initial physical examinationwas notable for thin body habitus and prominent cervical and supraclavicular adenopathy. She was referred to pediatric hematology-oncology for evaluation. An 18F-fluorodeoxyglucose (FDG) PET-CT revealed multifocal, hypermetabolic axial and appendicular skeletal metastases, extensive hypermetabolic lymphadenopathy, and multiple pulmonary nodules (Supporting Information Figure 1A). No evidence of intracranial diseasewas noted on brainMRI. Bonemarrow biopsy and aspirate were negative. Biopsy of the right iliac mass revealed atypical cell nodules with a histiocytic immunophenotype including CD68+, CD163+, lysozyme+,