Comparison of the different imaging modalities used to image pediatric oncology patients: A COG diagnostic imaging committee/SPR oncology committee white paper.

Diagnostic imaging is essential in the diagnosis and management, including surveillance, of known or suspected cancer in children. The independent and combined roles of the various modalities, consisting of radiography, fluoroscopy, ultrasonography (US), computed tomography (CT), magnetic resonance imaging (MRI), and nuclear medicine (NM), are both prescribed through protocols but also function in caring for complications that may occur during or subsequent to treatment such as infection, bleeding, or organ compromise. Use of a specific imaging modality may be based on situational circumstances such as a brain CT or MR for a new onset seizure, chest CT for respiratory signs or symptoms, or US for gross hematuria. However, in many situations, there are competing choices that do not easily lend themselves to a formulaic approach as options; these situations depend on the contributions of a variety of factors based on a combination of the clinical scenario and the strengths and limitations of the imaging modalities. Therefore, an improved understanding of the potential influence of the imaging decision pathways in pediatric cancer care can come from comparison among the individual diagnostic imaging modalities. The purpose of the following material to is to provide such a comparison. To do this, pediatric imaging content experts for the individual modalities of radiography and fluoroscopy, US, CT, MRI, and NM will discuss the individual modality strengths and limitations.

Lower skeletal muscle mass on CT body composition analysis is associated with adverse clinical course and outcome in children with COVID-19.

OBJECTIVES: To assess the association between body composition measures in children with COVID-19 and severity of the disease course and clinical outcome. METHODS: A retrospective study of children (< 19 years) with COVID-19 admitted to the hospital who underwent CT of the chest and/or abdomen was conducted. Data compiled from electronic medical records included demographics, body mass index (BMI), length of stay, ICU admission, invasive mechanical ventilation and death. Waist circumference and perimeters for skeletal muscle mass (abdominal, psoas and paraspinal muscles) were measured on an axial CT image at the level of the twelfth thoracic vertebra or first lumbar vertebra using FIJI software. RESULTS: Fifty-seven subjects were identified (54% male, median age 15.6 years, 61% Hispanic, 23% African-American). 25% (14/57) were admitted to the ICU and 21% (12/57) needed intubation. 9% (5/57) died. Waist circumference ranged between 53.2 and 138.4 cm (mean 86.58 ± 18.74 cm) and skeletal muscle mass ranged between 0.6 and 6.8 cm2 (mean 3.5 ± 1.19 cm2). Lower skeletal muscle mass had a univariate association with ICU admission (odds ratio (OR) 0.4; 95%CI 0.17-0.76; p = 0.01) and mortality (OR 0.22; 95%CI 0.04-0.69; p = 0.01). Multivariate analysis showed similar association after controlling for comorbidities (adjusted OR 0.46; 95%CI 0.19-0.95; p = 0.04 and adjusted OR 0.31; 95%CI 0.06-0.95; p = 0.04, respectively). There was no association between BMI or waist circumference with ICU stay, mechanical ventilation or mortality. CONCLUSION: Lower skeletal muscle mass is associated with an adverse clinical course and outcome in children with COVID-19.

CT imaging of esophageal foreign bodies in children: a pictorial essay.

Foreign body (FB) ingestion is common in children, particularly from 6 months to 3 years of age. As young children may be unable to provide a clinical history and the ingestion is often unwitnessed, imaging plays an important role in diagnosis, predicting outcomes and detecting complications that require surgical intervention. Since 2015, our institution's diagnostic algorithm for suspected airway foreign bodies has included a noncontrast airway FB CT (FB-CT) with the z-axis coverage spanning from the larynx to the proximal segmental bronchi of the lower lung zones. The effective dose of radiation from this FB-CT airway protocol is typically less than 1 mSv, compared to an effective dose of just under 1 mSv to up to 3 mSv for a fluoroscopic esophagram in children under 10 years of age and 1-3 mSv for a routine pediatric CT chest. In using the FB-CT airway protocol at our institution, we observed that esophageal rather than airway FBs were sometimes encountered on these exams. However, the confidence among radiologists for definitively diagnosing an esophageal foreign body on noncontrast CT was variable. Consequently, we created a teaching module of positive cases for our group of 21 pediatric body radiologists to increase their diagnostic confidence. This pictorial essay illustrates our institutional experience and can help others to confidently diagnose esophageal foreign bodies using a dedicated CT foreign body imaging protocol. At a similar radiation dose to a fluoroscopic esophagram, CT provides the additional advantage of an expedited diagnosis without the need for a radiologist on site.