Ionizing radiation from computed tomography versus anesthesia for magnetic resonance imaging in infants and children: patient safety considerations

Nitrogen single and multiple breath washout test and lung imaging to detect treatment-related pulmonary toxicity in paediatric cancer patients and survivors: a systematic review

BACKGROUND

Spirometry-based assessment of pulmonary function has limitations in detecting pulmonary toxicity following cancer treatment with chemotherapy, haematopoietic stem cell transplantation, radiotherapy or thoracic surgery. Nitrogen single and multiple breath washout tests are sensitive in assessing peripheral airway function, and lung imaging detects structural abnormalities, but little is known about their use in paediatric cancer patients and survivors. We aimed to 1) identify studies using nitrogen single or multiple breath washout tests and/or lung imaging to assess pulmonary toxicity in paediatric cancer patients and survivors, and 2) describe reported abnormalities.

METHOD

We systematically searched MEDLINE, Embase and the Cochrane Library for studies published in 1995‒2023. Eligible studies included paediatric cancer patients and survivors under 22 years of age receiving haematopoietic stem cell transplantation, chemotherapy, radiotherapy and/or thoracic surgery who underwent nitrogen single or multiple breath washout tests or lung imaging for detecting pulmonary toxicity. Two independent reviewers identified the studies, performed data extraction and assessed risk of bias.

RESULTS

We included 12 of 6544 publications. Three studies used nitrogen single or multiple breath washout tests, seven conducted lung imaging using computed tomography and two used both nitrogen single or multiple breath washout tests and lung imaging. Abnormal test results for nitrogen single and multiple breath washout tests and lung imaging were mainly reported following haematopoietic stem cell transplantation (67%). All studies performing lung imaging reported structural abnormalities. Study results were heterogeneous due to varying patient and methodological characteristics.

CONCLUSION

We identified a limited number of studies, mainly after haematopoietic stem cell transplantation, reporting functional and structural lung abnormalities in paediatric cancer patients and survivors. Longitudinal studies with standardised assessments using nitrogen single or multiple breath washout tests and lung imaging are needed to improve our understanding of treatment-related pulmonary toxicity.

Update on Whole-Body MRI Surveillance for Pediatric Cancer Predisposition Syndromes

Whole-body MRI (WBMRI) is an integral part of screening infants, children, and adolescents for presymptomatic neoplasms in certain cancer predisposition syndromes, which include Li-Fraumeni and constitutional mismatch repair deficiency syndromes, among others. The list of syndromes in which WBMRI adds value, as part of a comprehensive surveillance protocol, continues to evolve in response to new evidence, growing experience, and more widespread adoption. In July 2023, the AACR reconvened an international, multidisciplinary panel to revise and update recommendations stemming from the 2016 AACR Special Workshop on Childhood Cancer Predisposition. That initial meeting resulted in a series of publications in Clinical Cancer Research in 2017, including "Pediatric Cancer Predisposition Imaging: Focus on Whole-Body MRI." This 2024 review of WBMRI in cancer predisposition syndrome updates the 2017 WBMRI publication, the revised recommendations derived from the 2023 AACR Childhood Cancer Predisposition Workshop based on available data, societal guidelines, and expert opinion. Different aspects of acquiring and interpreting WBMRI, including diagnostic accuracy, are discussed. The application of WBMRI in resource-poor environments, as well as integration of whole-body imaging techniques with emerging technologies, such as cell-free DNA ("liquid biopsies") and artificial intelligence/machine learning, is also considered.

AVATAR 2.0: next level communication systems for radiotherapy through face-to-face video, biofeedback, translation, and audiovisual immersion

Purpose

This paper discusses an advanced version of our audiovisual-assisted therapeutic ambience in radiotherapy (AVATAR) radiolucent display systems designed for pediatric radiotherapy, enabling anesthesia-free treatments, video communication, and biofeedback. The scope of the AVATAR system is expanded here in two major ways: (i) through alternative mounting systems to accommodate a broader range of radiotherapy machines (specifically to fit robotic-arm and toroidal geometry photon radiotherapy and proton radiotherapy systems) and (ii) through additional hardware to provide video-calling, optimized audio for clear communication, and combined video inputs for biofeedback, translation, and other advanced functionalities.

Methods and materials

Because robustness requires strong parts and radio-transparency requires thin, light parts, three-dimensional printing was used to rapidly prototype hollow structures and to iteratively improve robustness. Two system designs were made: one that mounts superior and another that mounts inferior to the patient's head. Radiation dose measurements and calculations were conducted to assess dose perturbations at surface and depth due to the screen.

Results

For 6-MV volumetric modulated arc therapy (VMAT) plans, with and without the screen, the mean and maximum dose differences inside the planning target volume were 0.2% and 2.6% of the 200 cGy prescription, respectively. For a single static beam through the screen, the maximum measured excess surface dose was 13.4 ± 0.5%, and the largest measured dose attenuation at 5-cm water-equivalent depth was 2.1 ± 0.2%. These percentages are relative to the dose without the screen at those locations.

Conclusions

The radiolucent screen systems provided here are shown to give minimal dosimetric effects on megavoltage VMAT photon treatments. For static beams, however, surface dose effects should be considered when these beams pass through the thickest components of the screen. Design files are also provided.

Impact of upgrading from a 25-cm to a 30-cm z-axis field of view digital PET/CT in a pediatric hospital

BACKGROUND

Increased positron emission tomography (PET) scanner z-axis coverage provides an opportunity in pediatrics to reduce dose, anesthesia, or repeat scans due to motion.

OBJECTIVE

Recently, our digital PET scanner was upgraded from a 25-cm to a 30-cm z-axis coverage. We compare the two systems through National Electrical Manufacturing Association (NEMA) testing and evaluation of paired images from patients scanned on both systems.

MATERIALS AND METHODS

NEMA testing and a retrospective review of pediatric patients who underwent clinically indicated 18F-fluorodeoxyglucose (FDG) PET computed tomography (PET/CT) on both systems with unchanged acquisition parameters were performed. Image quality was assessed with liver signal to noise ratio (SNR-liver) and contrast to noise ratio (CNR) in the thigh muscle and liver with results compared with an unpaired t-test. Three readers independently reviewed paired (25 cm and 30 cm) images from the same patient, blinded to scanner configuration.

RESULTS

Expansion to 30 cm increased system sensitivity to 29.8% (23.4 cps/kBq to 30.4 cps/kBq). Seventeen patients (6 male/11 female, median age 12.5 (IQR 8.3-15.0) years, median weight 53.7 (IQR 34.2-68.7) kg) were included. SNR-liver and CNR increased by 35.1% (IQR 19.0-48.4%) and 43.1% (IQR 6.2-50.2%) (P-value <0.001), respectively. All readers preferred images from the 30-cm configuration. A median of 1 (IQR 1-1) for fewer bed positions was required with the 30-cm configuration allowing a median of 91 (IQR 47-136) s for shorter scans.

CONCLUSION

Increasing z-axis coverage from 25 to 30 cm on a current-generation digital PET scanner significantly improved PET system performance and patient image quality, and reduced scan duration.

Unusual Location of Neuroblastoma: A Report of Two Cases

Neuroblastoma is the most common extra-cranial solid tumor in children under the age of five years and is the second most prevalent malignancy in children after acute lymphoblastic leukemia. We are presenting two cases of neuroblastoma in children presented as intra-pelvic masses. The first patient presented with urinary retention while the second patient presented with ataxia. The initial imaging including ultrasound, CT scan, and MRI showed a large solid mass in the pelvis in both patients with extension to the spinal canal through the neural foramina at different levels. The histopathological results confirmed pelvic neuroblastomas. These cases highlight the rare locations of neuroblastoma in children and emphasize the variable presentations of this rare location. Knowledge of possible presentations of neuroblastoma aids early detection and expedites the proper management, especially in emergency settings.

Efficacy and Safety of Dexmedetomidine Compared to Other Needle-Free Pharmacological Sedation Methods in Pediatric Patients Undergoing Imaging Procedures

BACKGROUND

Pediatric patients often require sedation during magnetic resonance imaging (MRI) and computed tomography (CT) to ensure stillness and minimize stress. This meta-analysis compared the effectiveness and safety of 3 sedative agents-dexmedetomidine, midazolam, and chloral hydrate-for pediatric MRI/CT sedation.

METHODS

Six studies with a total of 633 patients were included in the analysis. Quality assessment revealed varying levels of bias risk. Dexmedetomidine exhibited a significantly higher successful sedation rate compared to midazolam (risk ratio [RR] = 0.43, 95% confidence interval [CI] [0.29-0.64]), but no statistically significant difference compared to chloral hydrate (RR = 0.94, 95% CI [0.60-1.45]). Chloral hydrate also showed a higher successful sedation rate compared to midazolam (RR = 0.46, 95% CI [0.25-0.83]). The onset of sedation time did not significantly differ between the 3 agents.

RESULTS

The dexmedetomidine group had a significantly higher incidence of bradycardia compared to the chloral hydrate group (RR = 0.17, 95% CI [0.05-0.59]), but no significant difference compared to the midazolam group (RR = 0.29, 95% CI [0.06-1.26]). No statistically significant differences were observed in the incidence of nausea and vomiting between the 3 groups.

CONCLUSIONS

Dexmedetomidine demonstrates effectiveness in pediatric MRI/CT sedation, offering advantages over midazolam and similar efficacy to chloral hydrate. Careful cardiovascular monitoring is essential during administration, particularly in patients with congenital heart disease. Sublingual and intranasal administration of dexmedetomidine is a viable option with high bioavailability. This meta-analysis contributes valuable insights into refining sedation protocols for pediatric imaging procedures, emphasizing efficacy and safety considerations.

Hypotensive Events in Pediatric Patients Receiving Dexmedetomidine for MRI

PURPOSE

Dexmedetomidine, the preferred pediatric sedating agent for magnetic resonance imaging (MRI), has the side effect of hypotension. Newer recommendations for reporting adverse events in pediatric procedural sedation include using a two-pronged definition. Our aim was to describe the incidence of hypotension in patients undergoing sedated MRI and to identify demographic and clinical factors associated with hypotension, applying a two-pronged definition, where a numerical threshold/clinical criterion must be met as well as at least one clinical intervention performed.

DESIGN

An observational cohort study.

METHODS

Medical record data were extracted for outpatients less than 18 years of age sedated primarily with dexmedetomidine for MRI in a single center for over a seven-year period. Patients who received propofol as an adjunct were also included. Hypotension was defined using a two-pronged approach, as a 20% reduction in systolic blood pressure from baseline lasting ≥10 minutes, coupled with a fluid bolus. Analysis included descriptive statistics, t tests and logistic regression using discrete-time survival analysis.

FINDINGS

Of the 1,590 patient encounters, 90 (5.7%) experienced hypotension. Males were significantly more likely to have hypotension. Patients with hypotension had overall longer appointment times, including longer sedation times and recovery time. Greater blood pressure (BP) variability in the preceding 20 minutes also increased the risk of hypotension.

CONCLUSIONS

Our lower incidence of hypotension is likely related to the two-pronged intervention-based definition used, as it likely more accurately reflects clinically meaningful hypotension. To our knowledge, this is the first study using this approach with this population. Research further examining the relationship between prolonged sedation, blood pressure variability, gender, hypotension, and recovery time is needed. Understanding these relationships will help interdisciplinary teams, including nurses in pediatric procedural areas, to reduce the incidence of hypotension, potentially maximize patient safety, and optimize throughput.

A survey of non-sedate practices when acquiring pediatric magnetic resonance imaging examinations

BACKGROUND

Improving access to magnetic resonance imaging (MRI) in childhood can be facilitated by making it faster and cheaper and reducing need for sedation or general anesthesia (GA) to mitigate motion. Some children achieve diagnostic quality MRI without GA through the use of non- practices fostering their cooperation and/or alleviating anxiety. Employed before and during MRI, these variably educate, distract, and/or desensitize patients to this environment.

OBJECTIVE

To assess current utilization of non-sedate practices in pediatric MRI, including variations in practice and outcomes.

MATERIALS AND METHODS

A survey-based study was conducted with 1372 surveys emailed to the Society for Pediatric Radiology members in February 2021, inviting one response per institution.

RESULTS

Responses from 50 unique institutions in nine countries revealed 49/50 (98%) sites used ≥ 1 non-sedate practice, 48/50 (96%) sites in infants < 6 months, and 11/50 (22%) for children aged 6 months to 3 years. Non-sedate practices per site averaged 4.5 (range 0-10), feed and swaddle used at 47/49 (96%) sites, and child life specialists at 35/49 (71%). Average success rates were moderate (> 50-75%) across all sites and high (> 75-100%) for 20% of sites, varying with specific techniques. Commonest barriers to use were scheduling conflicts and limited knowledge.

CONCLUSION

Non-sedate practice utilization in pediatric MRI was near-universal but widely variable across sites, ages, and locales, with room for broader adoption. Although on average non-sedate practice success rates were similar, the range in use and outcomes suggest a need for standardized implementation guidelines, including patient selection and outcome metrics, to optimize utilization and inform educational initiatives.

A narrative review of radiomics and deep learning advances in neuroblastoma: updates and challenges

Neuroblastoma is an extremely heterogeneous tumor that commonly occurs in children. The diagnosis and treatment of this tumor pose considerable challenges due to its varied clinical presentations and intricate genetic aberrations. Presently, various imaging modalities, including computed tomography, magnetic resonance imaging, and positron emission tomography, are utilized to assess neuroblastoma. Nevertheless, these conventional imaging modalities have limitations in providing quantitative information for accurate diagnosis and prognosis. Radiomics, an emerging technique, can extract intricate medical imaging information that is imperceptible to the human eye and transform it into quantitative data. In conjunction with deep learning algorithms, radiomics holds great promise in complementing existing imaging modalities. The aim of this review is to showcase the potential of radiomics and deep learning advancements to enhance the diagnostic capabilities of current imaging modalities for neuroblastoma.

Use of CEUS for Imaging Evaluation of Pediatric Peritonsillar Abscess

PURPOSE

Peritonsillar abscess can be diagnosed by B-mode ultrasound and cross-sectional imaging. The latter (with MRI being the modality of first choice in children) is associated with higher effort and risk for pediatric patients due to the administration of X-rays and/or the need of sedation. The purpose of this study is to evaluate whether the introduction of CEUS into the diagnostic algorithm for suspected pediatric peritonsillar abscess is suitable and advantageous.

MATERIALS AND METHODS

Single-institution retrospective review of data of pediatric patients who were presented to the department of pediatric radiology for sonographic evaluation under the suspicion of peritonsillar abscess. Diagnostic performance of CEUS was evaluated by using surgical exploration or clinical follow-up as the reference standard.

RESULTS

284 children included in the study underwent B-mode ultrasound. Mean age of all patients was 6,23 years. Peritonsillar abscess was the diagnosis in 42 patients. Diagnosis of peritonsillar abscess was made by B-mode ultrasound alone in 13 of 42 patients (31 %). In 17 of 42 patients (40 %), diagnosis was made by a combination of B-mode ultrasound and CEUS. Sensitivity rose from 37 % to 86 % in cases where B-mode ultrasound remained unclear and CEUS was used.

CONCLUSION

Contrast-enhanced ultrasound (CEUS) is suitable and efficient for the diagnosis of peritonsillar abscess in pediatric patients. It increases the sensitivity for the diagnosis of peritonsillar abscess and thereby reduces the need of additional cross-sectional imaging for the pediatric patients.

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.

Repeated Contrast-Enhanced Micro-CT Examinations Decrease Animal Welfare and Influence Tumor Physiology

OBJECTIVES

Computed tomography (CT) imaging is considered relatively safe and is often used in preclinical research to study physiological processes. However, the sum of low-dose radiation, anesthesia, and animal handling might impact animal welfare and physiological parameters. This is particularly relevant for longitudinal studies with repeated CT examinations. Therefore, we investigated the influence of repeated native and contrast-enhanced (CE) CT on animal welfare and tumor physiology in regorafenib-treated and nontreated tumor-bearing mice.

MATERIAL AND METHODS

Mice bearing 4T1 breast cancer were divided into 5 groups: (1) no imaging, (2) isoflurane anesthesia only, (3) 4 mGy CT, (4) 50 mGy CT, and (5) CE-CT (iomeprol). In addition, half of each group was treated with the multikinase inhibitor regorafenib. Mice were imaged 3 times within 1 week under isoflurane anesthesia. Behavioral alterations were investigated by score sheet evaluation, rotarod test, heart rate measurements, and fecal corticosterone metabolite analysis. Tumor growth was measured daily with a caliper. Tumors were excised at the end of the experiment and histologically examined for blood vessel density, perfusion, and cell proliferation.

RESULTS

According to the score sheet, animals showed a higher burden after anesthesia administration and in addition with CT imaging ( P < 0.001). Motor coordination was not affected by native CT, but significantly decreased after CE-CT in combination with the tumor therapy ( P < 0.001). Whereas tumor growth and blood vessel density were not influenced by anesthesia or imaging, CT-scanned animals had a higher tumor perfusion ( P < 0.001) and a lower tumor cell proliferation ( P < 0.001) for both radiation doses. The most significant difference was observed between the control and CE-CT groups.

CONCLUSION

Repeated (CE-) CT imaging of anesthetized animals can lead to an impairment of animal motor coordination and, thus, welfare. Furthermore, these standard CT protocols seem to be capable of inducing alterations in tumor physiology when applied repetitively. These potential effects of native and CE-CT should be carefully considered in preclinical oncological research.

Smartphone Integration of Artificial Intelligence for Automated Plagiocephaly Diagnosis

Positional plagiocephaly is a pediatric condition with important cosmetic implications affecting ∼40% of infants under 12 months of age. Early diagnosis and treatment initiation is imperative in achieving satisfactory outcomes; improved diagnostic modalities are needed to support this goal. This study aimed to determine whether a smartphone-based artificial intelligence tool could diagnose positional plagiocephaly.

Methods

A prospective validation study was conducted at a large tertiary care center with two recruitment sites: (1) newborn nursery, (2) pediatric craniofacial surgery clinic. Eligible children were aged 0-12 months with no history of hydrocephalus, intracranial tumors, intracranial hemorrhage, intracranial hardware, or prior craniofacial surgery. Successful artificial intelligence diagnosis required identification of the presence and severity of positional plagiocephaly.

Results

A total of 89 infants were prospectively enrolled from the craniofacial surgery clinic (n = 25, 17 male infants [68%], eight female infants [32%], mean age 8.44 months) and newborn nursery (n = 64, 29 male infants [45%], 25 female infants [39%], mean age 0 months). The model obtained a diagnostic accuracy of 85.39% compared with a standard clinical examination with a disease prevalence of 48%. Sensitivity was 87.50% [95% CI, 75.94-98.42] with a specificity of 83.67% [95% CI, 72.35-94.99]. Precision was 81.40%, while likelihood ratios (positive and negative) were 5.36 and 0.15, respectively. The F1-score was 84.34%.

Conclusions

The smartphone-based artificial intelligence algorithm accurately diagnosed positional plagiocephaly in a clinical environment. This technology may provide value by helping guide specialist consultation and enabling longitudinal quantitative monitoring of cranial shape.

Development and validation of a CT-based radiomics signature for identifying high-risk neuroblastomas under the revised Children's Oncology Group classification system

BACKGROUND

To develop and validate a radiomics signature based on computed tomography (CT) for identifying high-risk neuroblastomas.

PROCEDURE

This retrospective study included 339 patients with neuroblastomas, who were classified into high-risk and non-high-risk groups according to the revised Children's Oncology Group classification system. These patients were then randomly divided into a training set (n = 237) and a testing set (n = 102). Pretherapy CT images of the arterial phase were segmented by two radiologists. Pyradiomics package and FeAture Explorer software were used to extract and process radiomics features. Radiomics models based on linear discriminant analysis (LDA), logistic regression (LR), and support vector machine (SVM) were constructed, and the area under the curve (AUC), 95% confidence interval (CI), and accuracy were calculated.

RESULTS

The optimal LDA, LR, and SVM models had 11, 12, and 14 radiomics features, respectively. The AUC of the LDA model in the training and testing sets were 0.877 (95% CI: 0.833-0.921) and 0.867 (95% CI: 0.797-0.937), with an accuracy of 0.823 and 0.804, respectively. The AUC of the LR model in the training and testing sets were 0.881 (95% CI: 0.839-0.924) and 0.855 (95% CI: 0.781-0.930), with an accuracy of 0.823 and 0.804, respectively. The AUC of the SVM model in the training and testing sets were 0.879 (95% CI: 0.836-0.923) and 0.862 (95% CI: 0.791-0.934), with an accuracy of 0.827 and 0.804, respectively.

CONCLUSIONS

CT-based radiomics is able to identify high-risk neuroblastomas and may provide additional image biomarkers for the identification of high-risk neuroblastomas.

Pediatric Sedation/Anesthesia for MRI: Results From the Pediatric Sedation Research Consortium

BACKGROUND

Magnetic resonance imaging (MRI) is the most common imaging procedure requiring sedation/anesthesia in children. Understanding adverse events associated with sedation/anesthesia is important in making decisions regarding MRI vs. other imaging modalities. No large studies have evaluated the practice of pediatric sedation/anesthesia for MRI by a variety of pediatric specialists.

PURPOSE

Utilize a large pediatric sedation database to characterize the patients and adverse events associated with sedation/anesthesia for pediatric MRI.

STUDY TYPE

Retrospective analysis of prospectively collected data.

SUBJECTS

The Pediatric Sedation Research Consortium (PSRC) has 109,947 entries for sedations for MRI from November 10, 2011 through December 18, 2017.

ASSESSMENT

Patient demographics, sedative medications, interventions, and adverse events are described. Associations with adverse events were assessed. Trends in sedative medications used over time are examined.

STATISTICAL TESTS

Descriptive statistics, Chi-Squared and Fisher's Exact tests for categorical variables, logistic regression and assessment of trend using logistic regression and other method.

RESULTS

A total of 109,947 MRI-related sedations were examined. Most subjects (66.2%) were 5 years old or younger. Seizure or other neurologic issue prompted MRI in 63.7% of cases. Providers responsible for sedation/anesthesia included intensivists (49.3%), emergency medicine physicians (28.2%), hospitalists (10.2%), and anesthesiologists (9.8%). The most commonly used sedative agent was propofol (89.1%). The most common airway intervention was supplemental oxygen (71.7%), followed by head/airway repositioning (20.6%). Airway-related adverse events occurred in 8.4% of patients. Serious adverse events occurred in only 0.06% of patients, including three cases of cardiac arrest. No mortality was recorded. There was a statistically significant increase in the use of dexmedetomidine over time.

DATA CONCLUSIONS

Overall, adverse event rates were low. Sedation/anesthesia with propofol infusion and natural airway was the most common method used by this varied group of sedation providers. The use of dexmedetomidine increased over time.

EVIDENCE LEVEL

4 TECHNICAL EFFICACY: Stage 5.

Long-axial field-of-view PET/CT: perspectives and review of a revolutionary development in nuclear medicine based on clinical experience in over 7000 patients

Recently introduced long-axial field-of-view (LAFOV) PET/CT systems represent one of the most significant advancements in nuclear medicine since the advent of multi-modality PET/CT imaging. The higher sensitivity exhibited by such systems allow for reductions in applied activity and short duration scans. However, we consider this to be just one small part of the story: Instead, the ability to image the body in its entirety in a single FOV affords insights which standard FOV systems cannot provide. For example, we now have the ability to capture a wider dynamic range of a tracer by imaging it over multiple half-lives without detrimental image noise, to leverage lower radiopharmaceutical doses by using dual-tracer techniques and with improved quantification. The potential for quantitative dynamic whole-body imaging using abbreviated protocols potentially makes these techniques viable for routine clinical use, transforming PET-reporting from a subjective analysis of semi-quantitative maps of radiopharmaceutical uptake at a single time-point to an accurate and quantitative, non-invasive tool to determine human function and physiology and to explore organ interactions and to perform whole-body systems analysis. This article will share the insights obtained from 2 years' of clinical operation of the first Biograph Vision Quadra (Siemens Healthineers) LAFOV system. It will also survey the current state-of-the-art in PET technology. Several technologies are poised to furnish systems with even greater sensitivity and resolution than current systems, potentially with orders of magnitude higher sensitivity. Current barriers which remain to be surmounted, such as data pipelines, patient throughput and the hindrances to implementing kinetic analysis for routine patient care will also be discussed.

Needle-free pharmacological sedation techniques in paediatric patients for imaging procedures: a systematic review and meta-analysis

BACKGROUND

Sedation techniques and drugs are increasingly used in children undergoing imaging procedures. In this systematic review and meta-analysis, we present an overview of literature concerning sedation of children aged 0-8 yr for magnetic resonance imaging (MRI) procedures using needle-free pharmacological techniques.

METHODS

Embase, MEDLINE, Web of Science, and Cochrane databases were systematically searched for studies on the use of needle-free pharmacological sedation techniques for MRI procedures in children aged 0-8 yr. Studies using i.v. or i.m. medication or advanced airway devices were excluded. We performed a meta-analysis on sedation success rate. Secondary outcomes were onset time, duration, recovery, and adverse events.

RESULTS

Sixty-seven studies were included, with 22 380 participants. The pooled success rate for oral chloral hydrate was 94% (95% confidence interval [CI]: 0.91-0.96); for oral chloral hydrate and intranasal dexmedetomidine 95% (95% CI: 0.92-0.97); for rectal, oral, or intranasal midazolam 36% (95% CI: 0.14-0.65); for oral pentobarbital 99% (95% CI: 0.90-1.00); for rectal thiopental 92% (95% CI: 0.85-0.96); for oral melatonin 75% (95% CI: 0.54-0.89); for intranasal dexmedetomidine 62% (95% CI: 0.38-0.82); for intranasal dexmedetomidine and midazolam 94% (95% CI: 0.78-0.99); and for inhaled sevoflurane 98% (95% CI: 0.97-0.99).

CONCLUSIONS

We found a large variation in medication, dosage, and route of administration for needle-free sedation. Success rates for sedation techniques varied between 36% and 98%.

Paediatric kidney stone surgery: state-of-the-art review

While urolithiasis in children is rare, the global incidence is rising, and the volume of minimally invasive surgeries being performed reflects this. There have been many developments in the technology, which have supported the advancement of these interventions. However, innovation of this kind has also resulted in wide-ranging practice patterns and debate regarding how they should be best implemented. This is in addition to the extra challenges faced when treating stone disease in children where the patient population often has a higher number of comorbidities and for example, the need to avoid risk such as ionising exposure is higher. The overall result is a number of challenges and controversies surrounding many facets of paediatric stone surgery such as imaging choice, follow-up and different treatment options, for example, medical expulsive therapy, shockwave lithotripsy, ureteroscopy, and percutaneous nephrolithotomy. This article provides an overview of the current status of paediatric stone surgery and discussion on the key topics of debate.

Lung and large airway imaging: magnetic resonance imaging versus computed tomography

Disorders of the respiratory system are common in children and imaging plays an important role for initial diagnosis and follow-up evaluation. Radiographs are typically the first-line imaging test for respiratory symptoms in children and, when advanced imaging is required, CT has been the most frequently used imaging modality. However, because of increasing concern about potentially harmful effects of ionizing radiation on children, there has been a shift toward MRI in pediatric imaging. Although MRI of chest in children presents many technical challenges, recent advances in MRI technology are overcoming many of these issues, and MRI is now being used for evaluating the lung and large airway in children at centers with expertise in pediatric chest MRI. In this article we review the state of pediatric lung and large airway imaging, with an emphasis on cross-sectional modalities and the roles of MRI versus CT.

Target ischemic stroke model creation method using photoacoustic microscopy with simultaneous vessel monitoring and dynamic photothrombosis induction

The ischemic stroke animal model evaluates the efficacy of reperfusion and neuroprotective strategies for ischemic injuries. Various conventional methods have been reported to induce the ischemic models; however, controlling specific neurological deficits, mortality rates, and the extent of the infarction is difficult as the size of the affected region is not precisely controlled. In this paper, we report a single laser-based localized target ischemic stroke model development method by simultaneous vessel monitoring and photothrombosis induction using photoacoustic microscopy (PAM), which has minimized the infarct size at precise location with high reproducibility. The proposed method has significantly reduced the infarcted region by illuminating the precise localization. The reproducibility and validity of suggested method have been demonstrated through repeated experiments and histological analyses. These results demonstrate that our method can provide the ischemic stroke model closest to the clinical pathology for brain ischemia research from inducement, occurrence mechanisms to the recovery process.

Racial and ethnic disparities in pediatric magnetic resonance imaging missed care opportunities

BACKGROUND

Imaging missed care opportunities (MCOs), previously referred to as "no shows," impact timely patient diagnosis and treatment and can exacerbate health care disparities. Understanding factors associated with imaging MCOs could help advance pediatric health equity.

OBJECTIVE

To assess racial/ethnic differences in pediatric MR imaging MCOs and whether health system and socioeconomic factors, represented by a geography-based Social Vulnerability Index (SVI), influence racial/ethnic differences.

MATERIALS AND METHODS

We conducted a retrospective analysis of MR imaging MCOs in patients younger than 21 years at a pediatric academic medical center (2015-2019). MR imaging MCOs were defined as: scheduled but appointment not attended, canceled within 24 h, and canceled but not rescheduled. Mixed effects multivariable logistic regression assessed the association between MCOs and race/ethnicity and community-level social factors, represented by the SVI.

RESULTS

Of 68,809 scheduled MRIs, 6,159 (9.0%) were MCOs. A higher proportion of MCOs were among Black/African-American and Hispanic/Latino children. Multivariable analysis demonstrated increased odds of MCOs among Black/African-American (adjusted odds ratio [aOR] 1.9, 95% confidence interval [CI] 1.7-2.3) and Hispanic/Latino (aOR 1.5, 95% CI 1.3-1.7) children compared to White children. The addition of SVI >90th percentile to the adjusted model had no effect on adjusted OR for Black/African-American (aOR 1.9, 95% CI 1.7-2.2) or Hispanic/Latino (aOR 1.5, 95% CI 1.3-1.6) children. Living in a community with SVI >90th percentile was independently associated with MCOs.

CONCLUSION

Black/African-American and Hispanic/Latino children were almost twice as likely to experience MCOs, even when controlling for factors associated with MCOs. Independent of race/ethnicity, higher SVI was significantly associated with MCOs. Our study supports that pediatric health care providers must continue to identify systemic barriers to health care access for Black/African-American and Hispanic/Latino children and those from socially vulnerable areas.

Microwaves as Diagnostic Tool for Pituitary Tumors: Preliminary Investigations

To date, tumors, the second cause of death worldwide, are a modern medicine plight. The development of rapid, cost-effective and reliable prevention and diagnostics tools is mandatory to support clinicians and ensure patients’ adequate intervention. Pituitary tumors are a class of neoplasm, which calls for suitable and ad hoc diagnostic tools. Recently, microwaves have gained interest as a non-ionizing, non-invasive valuable diagnostic approach for identifying pathologic tissues according to their dielectric properties. This work deals with the preliminary investigation of the feasibility of using microwaves to diagnose pituitary tumors. In particular, it focuses on benign tumors of the adenohypophysis, e.g., the pituitary adenomas. It is assumed to access the region of interest of the pituitary region by following a trans-sphenoidal approach. The problem was modeled by developing an equivalent transmission line model of the multi-layered, lossy tissues (front bone of sphenoid sinuses, air in the sinuses, posterior bone of sphenoid sinuses, the pituitary gland and the tumor). The forward problem was developed to investigate the transmission coefficient for identifying the most favorable propagation conditions. Then, it was analyzed if, by the solution of an inverse problem, it is possible to reconstruct the permittivity and electrical conductivity profiles and identify the tumor presence. The results are promising since a maximum reconstruction error of 8% is found, in the worst case, thus paving the way for the use of microwaves for the diagnosis of pituitary tumors.

Assessing and conveying risks and benefits of imaging in neonates using ionizing radiation and sedation/anesthesia

Neonates represent a unique subset of the pediatric population that requires special attention and careful thought when implementing advanced cross-sectional imaging with CT or MRI. The ionizing radiation associated with CT and the sedation/anesthesia occasionally required for MRI present risks that must be balanced against the perceived benefit of the imaging examination in the unique and particularly susceptible neonatal population. We review the perceived risks of ionizing radiation and the more concrete risks of sedation/anesthesia in term and preterm neonates in the context of an imaging paradigm. When the expected diagnostic yield from CT and MRI is similar, and sedation is required for MRI but not for CT, CT likely has the higher benefit-to-risk ratio in the neonate. However, despite the risks, the most appropriate imaging modality should always be chosen after thoughtful consideration is given to each unique patient and informed discussions including radiology, anesthesia, neonatology and the parents/caregivers are pursued.

Management of esophageal button battery ingestions: resource utilization and outcomes

PURPOSE

Institutions are adopting the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN) guidelines for pediatric esophageal button battery ingestion (EBBI). Our objective was to evaluate the guidelines' impact on in-hospital resource utilization and short-term clinical outcomes in hemodynamically stable patients after endoscopic battery removal.

METHODS

A single-center retrospective review of all EBBI admissions from 2010 to 2020. Patients were divided into two groups based on adoption of national guidelines: pre-guideline (2010-2015) and post-guideline (2016-2020).

RESULTS

Sixty-five patients were studied (pre-guideline n = 23; post-guideline n = 42). Compared with pre-guideline, post-guideline use of magnetic resonance imaging (MRI) increased (2/23 [8.7%]; 30/42 [71.4%]; p < 0.001). Post-guideline increases resulted for median days (IQR) receiving antibiotics (0 [0, 4]; 6 [3, 8]; p = 0.01), total pediatric intensive care unit admission (0 [0, 1]; 3 [0, 6]; p < 0.001), and total hospital length of stay (5 [2, 11]; 11.5 [4, 17]; p = 0.02). Two patients in the post-guideline group had delayed presentations despite normal imaging: one with TEF and one with aorto-esophageal fistula. All survived to discharge.

CONCLUSION

In EBBI cases managed using the consensus based NASPHAGN guidelines, we report increased resource utilization without improved patient outcomes. Further research should evaluate post-guideline costs and resource utilization.

Magnetic resonance imaging of the pediatric mediastinum: updates, tips and tricks

Magnetic resonance imaging (MRI) of the pediatric mediastinum is challenging for the practicing radiologist. Many confounding factors add to the complexity of pediatric mediastinal MRI including small patient size, broad spectrum of mediastinal pathologies, motion artifacts and the need for sedation in a significant portion of children. However, with special attention to motion-reduction techniques and knowledge of pediatric-specific considerations, pediatric radiologists can help to provide accurate and timely diagnosis and also prevent multimodality imaging where MRI might be all that is needed. The purpose of this paper was present a practical review of pediatric mediastinal MRI with particular emphasis on diseases where MRI is the primary imaging modality of choice. Additionally, the author addresses those mediastinal processes for which MRI serves as a secondary problem-solving imaging tool.

Should I irradiate with computed tomography or sedate for magnetic resonance imaging?

In the context of pediatric cross-sectional imaging, the risk of ionizing radiation for CT and the potential adverse effects associated with sedation/anesthesia for MRI continue to provoke lively discussions in the pediatric literature and lay press. This is particularly true for issues relating to the risks of ionizing radiation for CT, which has been a topic of discussion for nearly two decades. In addition to understanding these potential risks and the importance of minimizing individual pediatric patient exposure to ionizing radiation, it is equally important for radiologists to be able to frame these risks with respect to the potential for adverse outcomes associated with the use of anesthesia for cross-sectional imaging in the pediatric population. Notably, before such risks can be estimated and compared, one should always consider the potential utility of each imaging modality for a given diagnosis. If one cross-sectional imaging modality is likely to be far superior to the other for a specific clinical question, every effort must be made to safely image the child, even if sedation/anesthesia is required.

Efficacy and Safety of Intranasal Dexmedetomidine vs. Oral Chloral Hydrate for Sedation in Children Undergoing Computed Tomography/Magnetic Resonance Imaging: A Meta-Analysis

OBJECTIVE

This meta-analysis aims to evaluate the sedative efficacy and safety of intranasal administration of dexmedetomidine (DEX) compared with oral chloral hydrate for Computed tomography (CT) or Magnetic Resonance Imaging (MRI) examination in Children.

METHODS

Cochrane Library, PubMed, Embase, Web of Science, China National Knowledge Infrastructure (CNKI), and China WanFang Databases were searched to collect randomized controlled trials (RCTs) investigating intranasal DEX (test group) vs. oral chloral hydrate (control group) in pediatric CT/MRI examinations up to December 30, 2021. The data were analyzed using Stata 15.0 software.

RESULTS

Seven RCTs with 1,846 children were identified. The meta-analysis results showed that the success rate of sedation (RR = 1.14, 95% CI: 1.03-1.26, P = 0.011), sedation onset time [weighted mean difference (WMD) = -0.87, 95% CI: -1.42 to -0.31, P = 0.002], sedation duration (WMD = -9.05, 95% CI:-14.69 to -3.42, P = 0.002), time to awakening (WMD = -9.75, 95% CI:-17.57 to -1.94, P = 0.014), and incidence of nausea and vomiting [relative risk (RR) = 0.09, 95% CI:0.04-0.23, P < 0.001) of the test group were significantly better than those of the control group. However, no significant differences were identified in incidence of hypotension (RR = 1.18, 95% CI: 0.51-2.74) and bradycardia (RR = 1.17, 95% CI: 0.13-22.11) between the two groups.

CONCLUSION

Intranasal administration of DEX is superior to oral chloral hydrate for sedation during pediatric CT/MRI examinations and has a better safety profile.

Multisystem Imaging Manifestations of Kawasaki Disease

Kawasaki disease (KD) is a common pediatric vasculitis syndrome involving medium- and small-sized arteries that is especially prevalent in early childhood (ie, age 6 months to 5 years). The diagnosis of KD is made on the basis of clinical features, such as fever, characteristic mucocutaneous changes, and nonsuppurative cervical lymphadenopathy. However, early diagnosis is often challenging because many children with KD present with atypical symptoms. The most serious complication of KD is coronary artery aneurysm caused by coronary arteritis. Prompt intravenous immunoglobulin therapy reduces the risk of cardiac morbidity. In addition, the systemic extension of KD-related vasculitis during the acute phase causes a variety of multisystem manifestations, including encephalopathy, stroke, retropharyngeal edema, pericarditis, myocarditis, KD shock syndrome, pulmonary lesions, intestinal pseudo-obstruction, gallbladder hydrops, arthritis, and myositis. These complications tend to be more common in affected children with atypical presentation. Radiologists can play an important role in the timely identification of diverse KD-associated morbidities and thus may contribute to the early diagnosis of atypical KD. Online supplemental material is available for this article. ^©RSNA, 2021.

1.5 vs 3 Tesla Magnetic Resonance Imaging: A Review of Favorite Clinical Applications for Both Field Strengths-Part 2

ABSTRACT

The second part of this review deals with experiences in neuroradiological and pediatric examinations using modern magnetic resonance imaging systems with 1.5 T and 3 T, with special attention paid to experiences in pediatric cardiac imaging. In addition, whole-body examinations, which are widely used for diagnostic purposes in systemic diseases, are compared with respect to the image quality obtained in different body parts at both field strengths. A systematic overview of the technical differences at 1.5 T and 3 T has been presented in part 1 of this review, as well as several organ-based magnetic resonance imaging applications including musculoskeletal imaging, abdominal imaging, and prostate diagnostics.

Quantitative imaging of the spine in adolescent idiopathic scoliosis: shifting the paradigm from diagnostic to comprehensive prognostic evaluation

PURPOSE

We aimed to provide a perspective review of the available quantitative imaging modalities of the spine for prognostic evaluation of the adolescent idiopathic scoliosis (AIS).

METHODS

A technical description of the current imaging technologies for quantitative assessment of the pediatric spine with scoliosis was provided, and the pros and cons of each method were discussed. Imaging modalities that quantify the overall 3D alignment of the spine as well as the structural specification of the spinal bone, intervertebral disc, endplates, and ligaments as it pertains to development and progression of the idiopathic spinal deformities in adolescents were discussed.

RESULTS

Low-dose and microdose stereoradiography, ultrasound, and rasterstereography provide quantitative imaging of the 3D spinal alignment with low or no radiation in standing posture which allows repetitive imaging for early detection of the curve development. Quantitative magnetic resonance imaging, including ultrashort dual-echo time and T1-rho can provide quantitative assessment of the spinal tissues relevant to development of idiopathic spinal deformity in pediatric population. New computed tomography scans that uses dual-energy can provides high-resolution measure of the current-state of the bone quality and morphology as well as the osteogenic properties of the bone by quantitative evaluation of the bone marrow.

CONCLUSION

The presented imaging modalities can provide a wide spectrum of quantifiable information relevant to development and progression of the spinal deformity. Clinical application of these technologies can change the paradigm in clinical assessment of the pediatric scoliosis by improving our understanding of the pathogenesis of the idiopathic scoliosis.

Free-breathing radial stack-of-stars three-dimensional Dixon gradient echo sequence in abdominal magnetic resonance imaging in sedated pediatric patients

BACKGROUND

There is a strong need for improvements in motion robust T1-weighted abdominal imaging sequences in children to enable high-quality, free-breathing imaging.

OBJECTIVE

To compare imaging time and quality of a radial stack-of-stars, free-breathing T1-weighted gradient echo acquisition (volumetric interpolated breath-hold examination [VIBE]) three-dimensional (3-D) Dixon sequence in sedated pediatric patients undergoing abdominal magnetic resonance imaging (MRI) against conventional Cartesian T1-weighed sequences.

MATERIALS AND METHODS

This study was approved by the institutional review board with informed consent obtained from all subjects. Study subjects included 31 pediatric patients (19 male, 12 female; median age: 5 years; interquartile range: 5 years) undergoing abdominal MRI at 3 tesla with a free-breathing T1-weighted radial stack-of-stars 3-D VIBE Dixon prototype sequence, StarVIBE Dixon (radial technique), between October 2018 and June 2019 with previous abdominal MR imaging using conventional Cartesian T1-weighed imaging (traditional technique). MRI component times were recorded as well as the total number of non-contrast T1-weighted sequences. Two radiologists independently rated images for quality using a scale from 1 to 5 according to the following metrics: overall image quality, hepatic edge sharpness, hepatic vessel clarity and respiratory motion robustness. Scores were compared between the groups.

RESULTS

Mean T1-weighted imaging times for all subjects were 3.63 min for radial exams and 8.01 min for traditional exams (P<0.001), and total non-contrast imaging time was 32.7 min vs. 43.9 min (P=0.002). Adjusted mean total MRI time for all subjects was 60.2 min for radial exams and 65.7 min for traditional exams (P=0.387). The mean number of non-contrast T1-weighted sequences performed in radial MRI exams was 1.0 compared to 1.9 (range: 0-6) in traditional exams (P<0.001). StarVIBE Dixon outperformed Cartesian methods in all quality metrics. The mean overall image quality (scale 1-5) was 3.95 for radial exams and 3.31 for traditional exams (P<0.001).

CONCLUSION

Radial stack-of-stars 3-D VIBE Dixon during free-breathing abdominal MRI in pediatric patients offers improved image quality compared to Cartesian T1-weighted imaging techniques with decreased T1-weighted and total non-contrast imaging time. This has important implications for children undergoing sedation for imaging.

Shear Wave Elastography: A Review on the Confounding Factors and Their Potential Mitigation in Detecting Chronic Kidney Disease

Early detection of chronic kidney disease is important to prevent progression of irreversible kidney damage, reducing the need for renal transplantation. Shear wave elastography is ideal as a quantitative imaging modality to detect chronic kidney disease because of its non-invasive nature, low cost and portability, making it highly accessible. However, the complexity of the kidney architecture and its tissue properties give rise to various confounding factors that affect the reliability of shear wave elastography in detecting chronic kidney disease, thus limiting its application to clinical trials. The objective of this review is to highlight the confounding factors presented by the complex properties of the kidney, in addition to outlining potential mitigation strategies, along with the prospect of increasing the versatility and reliability of shear wave elastography in detecting chronic kidney disease.

Neuroimaging for the Primary Care Provider: A Review of Modalities, Indications, and Pitfalls

When evaluating a child with a potential neurologic or neurodevelopmental disorder, identifying indications for imaging and the correct imaging modality to order can be challenging. This article provides an overview of computed tomography, MRI, ultrasonography, and radiography with an emphasis on indications for use, pitfalls to be avoided, and recent advances. A discussion of the appropriate use of ionizing radiation, intravenous contrast, and sedation is also provided.

Imaging sedation and anesthesia practice patterns in pediatric radiology departments - a survey of the Society of Chiefs of Radiology at Children's Hospitals (SCORCH)

BACKGROUND

There are few data describing practice patterns related to the use of sedation/anesthesia for diagnostic imaging in pediatric radiology departments.

OBJECTIVE

To understand current practice patterns related to imaging with sedation/anesthesia in pediatric radiology departments based on a survey of the Society of Chiefs of Radiology at Children's Hospitals (SCORCH) in conjunction with the American College of Radiology's Pediatric Imaging Sedation and Anesthesia Committee.

MATERIALS AND METHODS

A multi-question survey related to imaging with sedation/anesthesia in pediatric radiology departments was distributed to SCORCH member institutions in January 2019. A single reminder email was sent. Descriptive statistical analyses were performed.

RESULTS

Of the 84 pediatric radiology departments, 23 (27%) completed the survey. Fifty-seven percent of the respondents self-identified as academic/university-affiliated and 13% as a division/section in an adult radiology department. Imaging sedation (excluding general anesthesia) is commonly performed by pediatric anesthesiologists (76%) and intensive care unit physicians (intensivists, 48%); only 14% of departments expect their pediatric radiologists to supervise imaging sedation. Ninety-six percent of departments use child life specialists for patient preparation. Seventy percent of departments have preparatory resources available on a website, including simulation videos (26%) and audio clips (17%). Nearly half (48%) of the departments have a mock scanner to aid in patient preparation. Imaging sedation/anesthesia is most often scheduled at the request of ordering clinicians (65%), while 57% of departments allow schedulers to place patients into imaging sedation/anesthesia slots based on specified criteria.

CONCLUSION

Imaging sedation/anesthesia practice patterns vary among pediatric radiology departments, and understanding current approaches can help with standardization and practice improvement.

123Iodine-metaiodobenzylguanidine scintigraphy versus whole-body magnetic resonance imaging with diffusion-weighted imaging in children with high-risk neuroblastoma - pilot study

BACKGROUND

The prognostic value of the International Society of Paediatric Oncology European Neuroblastoma Research Network (SIOPEN) skeletal score using ¹²³iodine-metaiodobenzylguanidine (MIBG) has been confirmed for people with high-risk neuroblastoma. Whole-body MRI with diffusion-weighted imaging is used increasingly.

OBJECTIVE

To compare the original SIOPEN score and its adaption by diffusion-weighted imaging in high-risk stage 4 neuroblastoma and to evaluate any consequences of score differences on overall survival.

MATERIALS AND METHODS

This retrospective observational study included pediatric patients who underwent MIBG scintigraphy and whole-body MRI, including diffusion-weighted imaging, between 2010 and 2015. Semi-quantitative skeletal scores for each exam were calculated independently. A difference of two or more points was defined as clinically relevant and counted as M+ (more in diffusion-weighted imaging) or S+ (more in MIBG). In cases of a negative result in one of the studies, residual disease of 1 point was also rated as relevant. We tested correlation and differences on an exam basis and also grouped by different therapeutic conditions. Overall survival was used to evaluate prognostic relevance.

RESULTS

Seventeen children with 25 paired examinations were evaluated. Median MIBG scintigraphy score was 0 (interquartile range [IQR] 0-4, range 0-25) vs. a median whole-body MRI score of 1 (IQR 0-5.5, range 0-35) (P=0.018). A relevant difference between whole-body MRI and MIBG scintigraphy was noted in 14 of the 25 paired examinations (M+: n=9; S+: n=5). After treatment, the median survival of cases with M+ was 14 months (IQR 4-59, range 1-74 months), while S+ cases showed a median survival of 49 months (IQR 36-52, range 36-52 months) (P=0.413).

CONCLUSION

The SIOPEN scoring system is feasible for whole-body MRI but might result in slightly higher scores, probably because of MRI's superior spatial resolution. Further studies are necessary to validate any impact on prognosis.

Pediatric Minor Head Trauma: Factors Affecting the Anxiety of Parents

Managing the anxiety of the parents of pediatric patients with head trauma is challenging. This study aimed to examine the factors that affect anxiety levels of parents whose children were admitted to the emergency department with minor head trauma. In this prospective study, the parents of 663 consecutive pediatric patients were invited to answer a questionnaire. Parents of 600 children participated in the study. The parents who believed they were provided sufficient information and who were satisfied with the service received had significantly more improvement in anxiety-related questions. Cranial X-ray assessment had a significantly positive impact on the anxiety of the parents, whereas cranial computed tomography and neurosurgery consultation did not. In assessing pediatric minor head trauma, cranial computed tomography imaging and neurosurgery consultation should not be expected to relieve the anxiety of the parents. However, adequately informing them and providing satisfaction are the factors that could lead to improvement.

Essentials for aerosol delivery to term and pre-term infants

Effectively delivering pharmaceutical aerosols to the lungs of preterm and term infants represents a considerable technical challenge. Small infants are obligatory nose breathers, they have small airways, low tidal volumes and rapid respiration rates. It is ethically unacceptable to investigate aerosol deposition in vivo in newborns due to ethical concerns about the radiation exposure involved in imaging studies and drug delivery and blood draws in pharmacokinetics studies. The purpose of the work reported in this article was thus to report the use of modeling to develop an understanding of the regional deposition of aerosols in neonates and to build a theoretical basis for choosing an optimum aerosol size to maximize delivery and minimize variability. Recent data on aerosol deposition in the nasal airways of newborn term and preterm infants was coupled to an established, scalable, lung deposition model to investigate the effects of age, aerosol size and ventilation on regional airway deposition. In the term newborn infant lung deposition ranged from 25% to 35% depending on Geometric Standard Deviations (GSDs). Intrasubject variability was minimized for aerosols with larger GSD. However, mean lung deposition is reduced with increasing GSD. A compromise between maximum lung deposition and increased intersubject variability appears to be in the region of GSDs of 1.75. In the 30-week GA preterm infant lung deposition is slightly higher than in the term infant despite smaller airways and lower tidal volumes. This is likely due to the lower inhaled flow rates that are concomitant with lower lung volumes. Finally, when aerosol delivery is directly to the trachea, as it would be if delivered via an endotracheal tube there is a monotonic increase in lung deposition with increasing aerosol size with peripheral deposition peaking at 2 to 3 µm. However, practical limitations of aerosol transport through endotracheal tubes, limiting delivered aerosol size, likely caps lung deposition at around 30% to 30% of the delivered dose.

Current Use of Pediatric Cardiac Magnetic Resonance Imaging in Brazil

Fundamento

Dados sobre o uso de ressonância magnética cardíaca (RMC) em crianças no Brasil são escassos.

Objetivos

Buscamos oferecer informações sobre as práticas atuais de RMC pediátricas no Brasil.

Métodos

Um questionário foi enviado a médicos solicitantes de RMC de todo o país, cobrindo informações sobre si próprios, sobre seus serviços de RMC, contexto clínico dos pacientes e sobre os obstáculos para a realização de RMC em crianças. Para a análise estatística, um p < 0,05 bilateral foi considerado significativo.

Resultados

A pesquisa obteve 142 respostas. Foi relatado que a RMC está disponível para 79% dos respondentes, dos quais 52% raramente ou nunca a utilizam. As indicações mais comuns são cardiomiopatias (84%), pós-operatório de correção de tetralogia de Fallot (81%) e malformações do arco aórtico (53%). A complexidade do exame se correlacionou à relação RMC/cirurgia (Rho = 0,48, IC 95% = 0,32-0,62, p < 0,0001) e ao número de exames de RMC (Rho = 0,52, IC 95% = 0,38-0,64, p < 0,0001). A complexidade da RMC esteve associada à sua realização por cardiologistas pediátricos (RC 2,04, IC 95% 1,2-3,89, p < 0,01). Os principais obstáculos ao uso mais frequente de RMC foram o alto custo (65%), a necessidade de sedação (60%) e o número insuficiente de profissionais qualificados (55%).

Conclusão

A RMC pediátrica não é usada frequentemente no Brasil. A presença de um cardiologista pediátrico a frente dos exames esteve associado ao uso de RMC em pacientes mais complexos. O treinamento de especialistas em RMC pediátrica e a educação dos médicos solicitantes são passos importantes na direção de um uso mais abrangente de RMC no Brasil. (Arq Bras Cardiol. 2021; 116(2):305-312)

Current State of Imaging of Pediatric Pancreatitis: AJR Expert Panel Narrative Review

Pancreatitis is as common in children as it is in adults, though causes and accepted imaging strategies differ in children. In this narrative review we discuss the epidemiology of childhood pancreatitis and key imaging features for pediatric acute, acute recurrent, and chronic pancreatitis. We rely heavily on our collective experience in discussing advantages and disadvantages of different imaging modalities; practical tips for optimization of ultrasound, CT, and MRI with MRCP in children; and image interpretation pearls. Challenges and considerations unique to imaging pediatric pancreatitis are discussed, including timing of imaging, role of secretin-enhanced MRCP, utility of urgent MRI, severity prediction, autoimmune pancreatitis, and best methods for serial imaging. We suggest a methodical approach to pancreatic MRI interpretation in children and have included a sample structured report, and we provide consensus statements according to our experience imaging children with pancreatitis.

Advances in the Diagnosis and Management of Neonatal Sarcomas

Neonatal sarcomas comprise a heterogeneous group of rare soft tissue neoplasms that present unique diagnostic and therapeutic challenges. Recent advances in molecular profiling have improved diagnostic capabilities and reveal novel therapeutic targets. Clinical trials demonstrate differences in behavior between sarcoma subtypes that allow for better clinical management. Surgical resection has been replaced with a multimodal approach that includes chemotherapy and radiotherapy. Despite these advances, neonates with sarcoma continue to fare worse than histologically similar sarcomas in older children, likely reflecting differences in tumor biology and the complexities of neonatal medicine. This review focuses on recent advances in managing neonatal sarcomas.

Predictors of Anesthetic Exposure in Pediatric MRI

BACKGROUND. Anesthetic exposure in children may impact long-term neurocognitive outcomes. Therefore, minimizing pediatric MRI scan time in children under anesthesia and the associated anesthetic exposure is necessary. OBJECTIVE. The purpose of this study was to evaluate pediatric MRI scan time as a predictor of total propofol dose, considering imaging and clinical characteristics as covariates. METHODS. Electronic health records were retrospectively searched to identify MRI examinations performed from 2016 to 2019 in patients 0-18 years old who received propofol anesthetic. Brain; brain and spine; brain and abdomen; and brain, head, and neck MRI examinations were included. Demographic, clinical, and imaging data were extracted for each examination, including anesthesia maintenance phase time, MRI scan time, and normalized propofol dose. MRI scan time and propofol dose were compared between groups using a t test. A multiple linear regression with backward selection (threshold, p < .05) was used to evaluate MRI scan time as a predictor of total propofol dose, adjusting for sex, age, time between scan and study end, body part, American Society of Anesthesiologists (ASA) classification, diagnosis, magnet strength, and IV contrast medium administration as covariates. RESULTS. A total of 501 examinations performed in 426 patients (172 girls, 254 boys; mean age, 6.55 ± 4.59 [SD] years) were included. Single body part examinations were shorter than multiple body part examinations (mean, 52.7 ± 18.4 vs 89.3 ± 26.4 minutes) and required less propofol (mean, 17.7 ± 5.7 vs 26.1 ± 7.7 mg/kg; all p < .001). Among single body part examinations, a higher ASA classification, oncologic diagnosis, 1.5-T magnet, and IV contrast medium administration were associated with longer MRI scan times (all p ≤ .009) and higher propofol exposure (all p ≤ .005). In multivariable analysis, greater propofol exposure was predicted by MRI scan time (mean dose per minute of examination, 0.178 mg/kg; 95% CI, 0.155-0.200; p < .001), multiple body part examination (p = .04), and IV contrast medium administration (p = .048); lower exposure was predicted by 3-T magnet (p = .04). CONCLUSION. Anesthetic exposure during pediatric MRI can be quantified and predicted based on imaging and clinical variables. CLINICAL IMPACT. This study serves as a valuable baseline for future efforts to reduce anesthetic doses and scan times in pediatric MRI.

Consensus statement by the American Association of Clinical Endocrinology (AACE) and the American Head and Neck Society Endocrine Surgery Section (AHNS-ES) on Pediatric Benign and Malignant Thyroid Surgery

OBJECTIVES

To provide a clinical disease state review of recent relevant literature and to generate expert consensus statements regarding the breadth of pediatric thyroid cancer diagnosis and care, with an emphasis on thyroid surgery. To generate expert statements to educate pediatric practitioners on the state-of-the-art practices and the value of surgical experience in the management of this unusual and challenging disease in children.

METHODS

A literature search was conducted and statements were constructed and subjected to a modified Delphi process to measure the consensus of the expert author panel. The wording of statements, voting tabulation, and statistical analysis were overseen by a Delphi expert (J.J.S.).

RESULTS

Twenty-five consensus statements were created and subjected to a modified Delphi analysis to measure the strength of consensus of the expert author panel. All statements reached a level of consensus, and the majority of statements reached the highest level of consensus.

CONCLUSION

Pediatric thyroid cancer has many unique nuances, such as bulky cervical adenopathy on presentation, an increased incidence of diffuse sclerosing variant, and a longer potential lifespan to endure potential complications from treatment. Complications can be a burden to parents and patients alike. We suggest that optimal outcomes and decreased morbidity will come from the use of advanced imaging, diagnostic testing, and neural monitoring of patients treated at high-volume centers by high-volume surgeons.

Consensus Statement by the American Association of Clinical Endocrinology (AACE) and the American Head and Neck Society Endocrine Surgery Section (AHNS) on Pediatric Benign and Malignant Thyroid Surgery

OBJECTIVES

To provide a clinical disease state review of recent relevant literature and to generate expert consensus statements regarding the breadth of pediatric thyroid cancer diagnosis and care, with an emphasis on thyroid surgery. To generate expert statements to educate pediatric practitioners on the state-of-the-art practices and the value of surgical experience in the management of this unusual and challenging disease in children.

METHODS

A literature search was conducted and statements were constructed and subjected to a modified Delphi process to measure the consensus of the expert author panel. The wording of statements, voting tabulation, and statistical analysis were overseen by a Delphi expert (J.J.S.).

RESULTS

Twenty-five consensus statements were created and subjected to a modified Delphi analysis to measure the strength of consensus of the expert author panel. All statements reached a level of consensus, and the majority of statements reached the highest level of consensus.

CONCLUSION

Pediatric thyroid cancer has many unique nuances, such as bulky cervical adenopathy on presentation, an increased incidence of diffuse sclerosing variant, and a longer potential lifespan to endure potential complications from treatment. Complications can be a burden to parents and patients alike. We suggest that optimal outcomes and decreased morbidity will come from the use of advanced imaging, diagnostic testing, and neural monitoring of patients treated at high-volume centers by high-volume surgeons.

Neurological complications of pediatric cancer

Both the onset of various malignancies as well as the treatment of cancer can lead to neurologic symptoms which can be difficult to diagnose. In this review, we highlight the varied ways in which neurologic sequelae of cancer and its treatment manifest in children. Initial neurologic presentation may be secondary to mass effect or to immune-mediated paraneoplastic syndromes. Treatment effects on the nervous system may arise from surgery, chemotherapy, radiation, or bone marrow transplantation. In addition, the rapidly expanding field of immunotherapies for cancer has generated numerous new approaches to eradicating cancer including monoclonal antibodies, checkpoint inhibitors, and chimeric antigen receptor T cells (CAR-T cells), which have neurologic side effects mediated by immune responses that are also being recognized. Here we review common consult questions to the neurologist and our general approach to these scenarios including altered mental status, headaches, seizures, and sensorimotor complaints, considering the multifactorial nature of each.

Imaging of childhood urologic cancers: current approaches and new advances

Urologic tumors make up approximately 10% of all pediatric cancers, and include a variety of different histologies and imaging considerations. In this review, we discuss standard radiologic approaches for children with tumors arising in the genitourinary system, and identify important ways in which imaging affects the differential diagnosis, preoperative planning, and staging of these tumors. In addition, we provide an update on strategies to reduce the time of imaging, which may obviate the need for sedation in younger patients. Efforts to reduce a patient’s overall radiation exposure and subsequent risk of second malignancy are also detailed, including recent work on surveillance imaging following completion of therapy. Finally, we highlight new techniques such as radiomics that are now being investigated for patients with these malignancies.

The pediatric stomach - masses and mass-like pathology

Diagnostic imaging of pediatric gastric masses often provides a challenge for the practicing radiologist. Radiologists should be aware of this relatively unusual pathology, particularly in cross-sectional imaging findings. We will review pediatric gastric masses and mass-like lesions, focusing on neoplastic and inflammatory etiologies.