Planetary health: an imperative for pediatric radiology.

The global temperature has been increasing resulting in climate change. This negatively impacts planetary health that disproportionately affects the most vulnerable among us, especially children. Extreme weather events, such as hurricanes, tornadoes, wildfires, flooding, and heatwaves, are becoming more frequent and severe, posing a significant threat to our patients' health, safety, and security. Concurrently, shifts in environmental exposures, including air pollution, allergens, pathogenic vectors, and microplastics, further exacerbate the risks faced by children. In this paper, we provide an overview of pediatric illnesses that are becoming more prevalent and severe because of extreme weather events, global temperature increases, and shifts in environmental exposures. As members of pediatric health care teams, it is crucial for pediatric radiologists to be knowledgeable about the impacts of climate change on our patients, and continue to advocate for safe, healthier environments for our patients.

Spontaneous splenic rupture in a neonate: a case report and literature review.

Splenic rupture in a neonate is a rare but potentially fatal condition that may trigger evaluation for child abuse. It is a diagnosis of exclusion that has been reported in the surgical literature but may be underrecognized by pediatric radiologists. We report a case of a newborn with an unremarkable prenatal, delivery, and nursery course who presented with anemia, abdominal distension, and lethargy. Abdominal ultrasound with Doppler and computed tomography (CT) of the head, cervical spine, chest, abdomen, and pelvis without contrast showed findings of splenic rupture and anoxic brain injury. An extensive workup for traumatic, infectious, coagulopathic, and congenital etiologies was unrevealing, leading to a presumptive diagnosis of spontaneous splenic rupture in a neonate.

Red cell exchange transfusions increase cerebral capillary transit times and may alter oxygen extraction in sickle cell disease.

Persons with sickle cell disease (SCD) suffer from chronic hemolytic anemia, reduced blood oxygen content, and lifelong risk of silent and overt stroke. Major conventional stroke risk factors are absent in most individuals with SCD, yet nearly 50% have evidence of brain infarcts by the age of 30 years, indicating alternative etiologies for ischemia. We investigated whether radiological evidence of accelerated blood water transit through capillaries, visible on arterial spin labeling (ASL) magnetic resonance imaging, reduces following transfusion-induced increases in hemoglobin and relates to oxygen extraction fraction (OEF). Neurological evaluation along with anatomical and hemodynamic imaging with cerebral blood flow (CBF)-weighted pseudocontinuous ASL and OEF imaging with T2 -relaxation-under-spin-tagging were applied in sequence before and after blood transfusion therapy (n = 32) and in a comparator cohort of nontransfused SCD participants on hydroxyurea therapy scanned at two time points to assess stability without interim intervention (n = 13). OEF was calculated separately using models derived from human hemoglobin-F, hemoglobin-A, and hemoglobin-S. Gray matter CBF and dural sinus signal, indicative of rapid blood transit, were evaluated at each time point and compared with OEF using paired statistical tests (significance: two-sided p < 0.05). No significant change in sinus signal was observed in nontransfused participants (p = 0.650), but a reduction was observed in transfused participants (p = 0.034), consistent with slower red cell transit following transfusion. The dural sinus signal intensity was inversely associated with OEF pretransfusion (p = 0.011), but not posttransfusion. Study findings suggest that transfusion-induced increases in total hemoglobin may lengthen blood transit times through cerebral capillaries and alter cerebral OEF in SCD.

Imaging of pediatric spine and spinal cord tumors: A COG Diagnostic Imaging Committee/SPR Oncology Committee/ASPNR White Paper.

Childhood spinal tumors are rare. Tumors can involve the spinal cord, the meninges, bony spine, and the paraspinal tissue. Optimized imaging should be utilized to evaluate tumors arising from specific spinal compartments. This paper provides consensus-based recommendations for optimized imaging of tumors arising from specific spinal compartments at diagnosis, follow-up during and after therapy, and response assessment.

Systematic Approach to Pediatric Macrocephaly.

Macrocephaly, defined as a head circumference greater than 2 standard deviations above the mean, is a relatively common presenting symptom in the pediatric population at routine well-child examinations and a common indication for neuroimaging. Multiple imaging modalities are complementary in evaluating macrocephaly, including US, CT, and MRI. The differential diagnosis for macrocephaly is broad, and many disease processes lead to macrocephaly only when the sutures are open. In patients with closed sutures, these entities instead lead to increased intracranial pressure, according to the Monroe-Kellie hypothesis, which states that there is an equilibrium between intracranial constituents due to the fixed intracranial volume. The authors describe a useful paradigm for classifying macrocephaly by identifying which of the four components of the cranium (ie, cerebrospinal fluid, blood and vasculature, brain parenchyma, or calvarium) has an increased volume. Patient age, additional imaging findings, and clinical symptoms are also useful features. Most cases in the pediatric population are due to increased cerebrospinal fluid spaces, such as benign enlargement of the subarachnoid space, which must be carefully distinguished from subdural fluid collections in patients with accidental or nonaccidental trauma. Other common causes of macrocephaly are discussed, including hydrocephalus secondary to an aqueductal web, hemorrhage, or a neoplasm. The authors also provide information on some of the rarer diseases for which imaging may provide the impetus for genetic testing (eg, overgrowth syndromes and metabolic disorders). ©RSNA, 2023 Quiz questions for this article are available through the Online Learning Center.

Imaging the Cerebral Veins in Pediatric Patients: Beyond Dural Venous Sinus Thrombosis.

The range of intracranial venous anomalies in children differs from that in adults. As a commonly encountered highly morbid disease, sinovenous thrombosis has been discussed extensively in the literature, and the associated imaging considerations are similar in pediatric and adult patients. The authors shift the focus to less frequently discussed cerebral venous diseases in pediatric patients. First, the practical embryology pertinent to malformations, syndromes, and variants such as vein of Galen aneurysmal malformation, Sturge-Weber syndrome, and developmental venous anomalies are discussed. Second, anatomic considerations that are applicable to neuroimaging in pediatric patients with cerebral venous anomalies are reviewed. In the discussion of anatomy, special attention is given to the medullary venous system that serves the cerebral white matter, superficial cortical veins (tributaries of the dural venous sinuses), and bridging veins, which carry blood from the superficial cortical veins through the potential subdural space into the dural venous sinuses. Third, the selection of imaging modalities (US, CT and CT venography, and MRI) is addressed, and various MR venographic pulse sequences (time-of-flight, phase-contrast, and contrast-enhanced sequences) are compared. Finally, a broad variety of congenital and acquired superficial and deep venous diseases in children are reviewed, with emphasis on less frequently discussed entities involving the medullary (eg, deep medullary venous engorgement and thrombosis, periventricular hemorrhagic venous infarction due to germinal matrix hemorrhage), cortical (eg, cortical venous thrombosis), and bridging (eg, acute and chronic manifestations of injury in abusive head trauma) veins, as well as the deep veins and dural venous sinuses (eg, varix). © RSNA, 2023 Quiz questions for this article are available through the Online Learning Center. Online supplemental material and the slide presentation from the RSNA Annual Meeting are available for this article.

Imaging of Vertebral Artery Dissection in Children: An Underrecognized Condition with High Risk of Recurrent Stroke.

Vertebral artery dissection (VAD) is a common cause of a rare condition, pediatric posterior circulation arterial ischemic stroke (PCAIS). VAD is clinically important due to the risk of multifocal and continuing infarcts from artery-to-artery thromboembolism, with the potential for occlusion of arteries that perfuse the brainstem. Early diagnosis is important, as recurrent stroke is a common effect of VAD in children. Although the relative efficacies of different treatment regimens for VAD in children remain unsettled, early initiation of treatment can mitigate the risk of delayed stroke. Clinical diagnosis of PCAIS may be delayed due to multiple factors, including nonspecific symptoms and the inability of younger patients to express symptoms. In fact, subacute or chronic infarcts are often present at initial imaging. Although the most common cause of isolated PCAIS is VAD, imaging of the cervical arteries has been historically underused in this setting. Cervical vascular imaging (MR angiography, CT angiography, and digital subtraction angiography) for VAD must be optimized to detect the sometimes subtle findings, which may be identified at initial or follow-up imaging. Osseous variants of the craniocervical junction and upper cervical spine and other extrinsic lesions that may directly injure the vertebral arteries or lead to altered biomechanics have been implicated in some cases. The authors review characteristic imaging features and optimized imaging of VAD and associated PCAIS and related clinical considerations. Identification of VAD has important implications for evaluation, treatment, and imaging follow-up, as this condition may result in progressive arteriopathy and recurrent stroke. © RSNA, 2023 Supplemental material is available for this article. Quiz questions for this article are available through the Online Learning Center.

Complications of Cancer Therapy in Children: A Comprehensive Review of Neuroimaging Findings.

ABSTRACT: Complications of cancer therapy in children can result in a spectrum of neurologic toxicities that may occur at the initiation of therapy or months to years after treatment. Although childhood cancer remains rare, increasing survival rates mean that more children will be living longer after cancer treatment. Therefore, complications of cancer therapy will most likely occur with increasing frequency.At times, it is very difficult to differentiate between therapeutic complications and other entities such as tumor recurrence, development of secondary malignancy, and infection (among other conditions). Radiologists often play a key role in the diagnosis and evaluation of pediatric patients with malignancies, and thus, awareness of imaging findings of cancer complications and alternative diagnoses is essential in guiding management and avoiding misdiagnosis. The aim of this review article is to illustrate the typical neuroimaging findings of cancer therapy-related toxicities, including both early and late treatment effects, highlighting pearls that may aid in making the appropriate diagnosis.

Complications of Cancer Therapy in Children: A Comprehensive Review of Body Imaging Findings.

ABSTRACT: Complications of cancer therapy in children can result in a spectrum of toxicities that can affect any organ system and result in a range of morbidity. Complications may occur at the initiation of therapy or years following treatment. Although childhood cancer remains rare, increasing survival rates means more children are living longer following their treatment. Radiologists often play an important role in the diagnosis and evaluation of these complications, and thus, awareness of their imaging findings is essential to guide management and avoid misdiagnosis. This second part of a 2-part review aims to illustrate the typical body imaging findings of cancer therapy-related toxicities, including both early and late treatment effects. The article also discusses the differential diagnosis of imaging findings, highlighting pearls and pitfalls in making the appropriate diagnosis.

A comparison of MRI appearance and surgical detethering rates between intrauterine and postnatal myelomeningocele closures: a single-center pilot matched cohort study.

INTRODUCTION: Intrauterine myelomeningocele repair (IUMR) and postnatal myelomeningocele repair (PNMR) differ in terms of both setting and surgical technique. A simplified technique in IUMR, in which a dural onlay is used followed by skin closure, has been adopted at our institution. The goal of this study was to compare the rates of clinical tethering in IUMR and PNMR patients, as well as to evaluate the appearance on MRI. METHODS: We conducted a retrospective review of 36 patients with MMC repaired at our institution, with 2:1 PNMR to IUMR matching based on lesion level. A pediatric neuroradiologist blinded to the clinical details reviewed the patients' lumbar spine MRIs for the distance from neural tissue to skin and the presence or absence of a syrinx. An EMR review was then done to evaluate for detethering procedures and need for CSF diversion. RESULTS: Mean age at MRI was 4.0 years and mean age at last follow-up was 6.1 years, with no significant difference between the PNMR and IUMR groups. There was no significant difference between groups in the distance from neural tissue to skin (PNMR 13.5 mm vs IUMR 17.6 mm; p = 0.5). There was no difference in need for detethering operations between groups (PNMR 12.5% vs IUMR 16.7%; RR 0.75; CI 0.1-5.1). CONCLUSIONS: There was no significant difference between postnatal- and intrauterine-repaired myelomeningocele on MRI or in need for detethering operations. These results imply that a more straightforward and time-efficient IUMR closure technique does not lead to an increased rate of tethering when compared to the multilayered PNMR.

Making intussusception reductions easier: use of medical air in lieu of manual pump.

BACKGROUND: Pneumatic reduction of ileocolic intussusception is commonly performed with manual insufflators. The challenge of operating a handheld device while controlling the fluoroscope and monitoring the reduction could be obviated if the manual insufflation could be eliminated. OBJECTIVE: The aim in this retrospective study was to describe and evaluate the use of medical wall air in intussusception reduction. MATERIALS AND METHODS: We retrospectively reviewed all intussusception reductions over a period of years: from 2015 to 2018 using the manual insufflator and from 2018 to 2021 using medical air. We compared success rates, complication rates and time to reduction as documented on fluoroscopic image time stamps. Demographic data were obtained from the medical record. Attending radiologists and fluoroscopic technologists indicated their preference between methods, ease of use, perceived duration of reduction and perceived difference in success rates through an anonymous internal survey. RESULTS: There were 179 first reduction attempts in 167 patients (93 attempts during the period using the manual insufflator and 86 after converting to wall air). There was no difference in reduction duration (8:23 min for insufflation, 8:22 min for wall air, P=0.99) and no statistically significant difference in success rate (66.8% for insufflation and 79.1% for wall air, P=0.165). All survey respondents preferred the wall air method. The vast majority (93%) perceived that the wall air method was faster. CONCLUSION: Hospital wall air can be used to successfully reduce intussusceptions without incurring time burden or loss of effectiveness. The method leads to a perception of increased efficiency.

Pediatric Central Nervous System Cancers, Version 2.2023, NCCN Clinical Practice Guidelines in Oncology.

Central nervous system (CNS) cancers account for approximately one quarter of all pediatric tumors and are the leading cause of cancer-related death in children. More than 4,000 brain and CNS tumors are diagnosed each year in children and teens, and the incidence rate has remained stagnant in recent years. The most common malignant pediatric CNS tumors are gliomas, embryonal tumors consisting of predominately medulloblastomas, and germ cell tumors. The inaugural version of the NCCN Guidelines for Pediatric Central Nervous System Cancers focuses on the diagnosis and management of patients with pediatric diffuse high-grade gliomas. The information contained in the NCCN Guidelines is designed to help clinicians navigate the complex management of pediatric patients with diffuse high-grade gliomas. The prognosis for these highly aggressive tumors is generally poor, with 5-year survival rates of <20% despite the use of combined modality therapies of surgery, radiation therapy and systemic therapy. Recent advances in molecular profiling has expanded the use of targeted therapies in patients whose tumors harbor certain alterations. However, enrollment in a clinical trial is the preferred treatment for eligible patients.

Characterization of germinal matrix hemorrhage in extremely premature infants: recognition of posterior location and diagnostic pitfalls.

BACKGROUND: Traditionally, descriptions of germinal matrix hemorrhage (GMH), derived from observations in preterm and very preterm infants, indicate its location at the caudothalamic grooves. However, before the germinal matrix begins to recede at approximately 28 weeks' gestational age (GA), it extends along the floor of the lateral ventricles far posterior to the caudothalamic grooves. Germinal matrix-intraventricular hemorrhage (GMH-IVH) can occur along any site from which the germinal matrix has not yet involuted. Therefore, as current advances in neonatology have allowed the routine survival of extremely preterm infants as young as 23 weeks' GA, postnatal GMH-IVH can occur in previously undescribed locations. Hemorrhage in the more posterior GMH on head ultrasound, if unrecognized, may lead to errors in diagnosis and mislocalization of this injury to the periventricular white matter or lateral walls of the lateral ventricles instead of to the subependyma, where it is in fact located. OBJECTIVE: Our aim is to describe posterior GMH in extremely premature infants, including its characteristic imaging appearance and potential pitfalls in diagnosis. MATERIALS AND METHODS: Over a 5-year period, all consecutive extremely preterm infants of 27 weeks' GA or less who developed GMH-IVH of any grade were included. A consecutive group of 100 very preterm infants of 31 weeks' GA with a GMH-IVH of any grade served as controls. RESULTS: In 106 extremely preterm neonates (mean GA: 25 weeks, range: 23.1-26.6 weeks) with 212 potential lateral ventricular germinal matrix bleeding sites, 159 sites had bleeds. In 70/159 (44%), the GMH-IVH was located posterior to the caudothalamic grooves and the foramina of Monro, 52 (32.7%) were both anterior and posterior and 21 (13.2%) were exclusively anterior. In 16 ventricles with intraventricular hemorrhage, an origin site in the germinal matrix could not be determined. In the control population of very preterm infants, all hemorrhages were at the anterior caudothalamic grooves and 95% were grade I. CONCLUSION: Unlike the older very preterm and moderately preterm infants that form the basis of our GMH-IVH description and classification, the extremely preterm infants now routinely surviving have a more fetal pattern of germinal matrix distribution, which is reflected in a different distribution and size of germinal matrix injury. We report the postnatal occurrence of subependymal GMH-IVH in extremely preterm infants in these more primitive, posterior locations, its potential imaging pitfalls and sonographic findings.

Magnetic resonance imaging of the brainstem in children, part 1: imaging techniques, embryology, anatomy and review of congenital conditions.

Part 1 of this series of two articles describes conventional and advanced MRI techniques that are useful for evaluating brainstem pathologies. In addition, it provides a review of the embryology, normal progression of myelination, and clinically and radiologically salient imaging anatomy of the normal brainstem. Finally, it discusses congenital diseases of the brainstem with a focus on distinctive imaging features that allow for differentiating pathologies. Part 2 of this series of two articles includes discussion of neoplasms; infections; and vascular, demyelinating, toxic and metabolic, and miscellaneous disease processes affecting the brainstem. The ultimate goal of this pair of articles is to empower the radiologist to add clinical value in the care of pediatric patients with brainstem pathologies.

Magnetic resonance imaging of the brainstem in children, part 2: acquired pathology of the pediatric brainstem.

Part 1 of this series of two articles describes conventional and advanced MRI techniques that are useful for evaluating brainstem pathologies. In addition, it provides a review of the embryology, normal progression of myelination, and clinically and radiologically salient imaging anatomy of the normal brainstem. Finally, it discusses congenital diseases of the brainstem with a focus on distinctive imaging features that allow for differentiating pathologies. Part 2 of this series of two articles includes discussion of neoplasms; infections; and vascular, demyelinating, toxic, metabolic and miscellaneous disease processes affecting the brainstem. The ultimate goal of this pair of articles is to empower the radiologist to add clinical value in the care of pediatric patients with brainstem pathologies.

Meningoencephalitis due to Spotted Fever Rickettsioses, Including Rocky Mountain Spotted Fever.

BACKGROUND: The spotted fever rickettsioses (SFR), including Rocky Mountain spotted fever, are tick-borne infections with frequent neurologic involvement. High morbidity and mortality make early recognition and empiric treatment critical. Most literature on SFR meningoencephalitis predates widespread magnetic resonance imaging (MRI) utilization. To better understand the contemporary presentation and outcomes of this disease, we analyzed clinical and radiographic features of patients with SFR meningoencephalitis. METHODS: Patients were identified through hospital laboratory-based surveillance or through the Tennessee Unexplained Encephalitis Study. Cases meeting inclusion criteria underwent medical records review and, when available, independent review of the neuroimaging. RESULTS: Nineteen cases (11 children, 8 adults) met criteria for SFR meningoencephalitis. Rash was significantly more common in children than adults (100% vs 50%, respectively), but other clinical features were similar between the 2 groups. Cerebrospinal fluid pleocytosis and protein elevation were each seen in 87.5% of cases, and hypoglycorrhachia was present in 18.8% of cases. The "starry sky" sign (multifocal, punctate diffusion restricting or T2 hyperintense lesions) was seen on MRI in all children, but no adults. Ninety percent of patients required intensive care unit admission and 39% were intubated. Outcomes were similar between adults and children, with only 46% making a complete recovery by the time of discharge. CONCLUSIONS: SFR meningoencephalitis is a life-threatening infection. The clinical presentation varies between adults and children based on the presence of rash and brain MRI findings. The starry sky sign was ubiquitous in children and should prompt consideration of empiric treatment for SFR when present.

Assessment of gadolinium deposition in the brain tissue of pediatric and adult congenital heart disease patients after contrast enhanced cardiovascular magnetic resonance.

BACKGROUND: Contrast enhanced magnetic resonance imaging (MRI) is an important tool for the assessment of extracardiac vasculature and myocardial viability. Gadolinium (Gd) brain deposition after contrast enhanced MRI has recently been described and resulted in a warning issued by the United States Food and Drug Administration. However, the prevalence of brain deposition in children and adults with congenital heart disease (CHD) undergoing cardiovascular magnetic resonance (CMR) is unclear. We hypothesized that Gd exposure as part of one or more CMRs would lead to a low rate of brain deposition in pediatric and adult CHD patients. METHODS: We queried our institutional electronic health record for all pediatric and adult CHD patients who underwent contrast enhanced CMR from 2005 to 2018 and had a subsequent brain MRI. Cases were age- and gender-matched to controls who were never exposed to Gd and underwent brain MRIs. The total number of contrast enhanced MRIs, type of Gd, and total Gd dose were determined. Brain MRIs were reviewed by a neuroradiologist for evidence of Gd deposition using qualitative and quantitative assessment. Quantitative assessment was performed using the dentate nucleus to pons signal intensity ratio (dp-SIR) on T1 weighted imaging. Continuous variables were analyzed using Mann-Whitney U and Spearman rank correlation tests. Normal SIR was defined as the 95% CI of the control population dp-SIR. RESULTS: Sixty-two cases and 62 controls were identified. The most contrast enhanced MRIs in a single patient was five and the largest lifetime dose of Gd that any patient received was 0.75 mmol/kg. There was no significant difference in the mean dp-SIR of cases and controls (p = 0.11). The dp-SIR was not correlated with either the lifetime dose of Gd (rs = 0.21, p = 0.11) or the lifetime number of contrast enhanced studies (rs = 0.21, p = 0.11). Two cases and 2 controls had dp-SIRs above the upper bound of the 95% confidence interval for the control group. One case had qualitative imaging-based evidence of Gd deposition in the brain but had a dp-SIR within the normal range. CONCLUSION: In our cohort of pediatric and adult CHD patients undergoing contrast enhanced CMR, there was a low incidence of qualitative and no significant quantitative imaging-based evidence of Gd brain deposition.

Differential cerebral hemometabolic responses to blood transfusions in adults and children with sickle cell anemia.

BACKGROUND: Blood transfusions are administered to children and adults with sickle cell anemia (SCA) for secondary stroke prevention, or as treatment for recurrent pain crises or acute anemia, but transfusion effects on cerebral hemodynamics and metabolism are not well-characterized. PURPOSE: To compare blood transfusion-induced changes in hemometabolic parameters, including oxygen extraction fraction (OEF) and cerebral blood flow (CBF), within and between adults and children with SCA. STUDY TYPE: Prospective, longitudinal study. SUBJECTS: Adults with SCA (n = 16) receiving simple (n = 7) or exchange (n = 9) transfusions and children with SCA (n = 11) receiving exchange transfusions were scanned once when hematocrit was near nadir and again within 7 days of transfusion. Adult controls without SCA or sickle trait (n = 7) were scanned twice on separate days. FIELD STRENGTH/SEQUENCE: 3.0T T1 -weighted, T2 -weighted, and T2 -relaxation-under-spin-tagging (TRUST) imaging, and phase contrast angiography. ASSESSMENT: Global OEF was computed as the relative difference between venous oxygenation (from TRUST) and arterial oxygenation (from pulse oximetry). Global CBF was computed as total blood flow to the brain normalized by intracranial tissue volume. STATISTICAL TESTS: Hemometabolic variables were compared using two-sided Wilcoxon signed-rank tests; associations were analyzed using two-sided Spearman's correlation testing. RESULTS: In adults with SCA, posttransfusion OEF = 0.38 ± 0.05 was lower (P = 0.001) than pretransfusion OEF = 0.45 ± 0.09. A change in OEF was correlated with increases in hematocrit (P = 0.02; rho = -0.62) and with pretransfusion hematocrit (P = 0.02; rho = 0.65). OEF changes after transfusion were greater (P = 0.002) in adults receiving simple versus exchange transfusions. Posttransfusion CBF = 77.7 ± 26.4 ml/100g/min was not different (P = 0.27) from pretransfusion CBF = 82.3 ± 30.2 ml/100g/min. In children with SCA, both posttransfusion OEF = 0.28 ± 0.04 and CBF = 76.4 ± 26.4 were lower than pretransfusion OEF = 0.36 ± 0.06 (P = 0.004) and CBF = 96.4 ± 16.5 (P = 0.004). DATA CONCLUSION: Cerebral OEF reduces following transfusions in adults and children with SCA. CBF reduces following transfusions more often in children compared to adults, indicating that vascular reserve capacity may remain near exhaustion posttransfusion in many adults. LEVEL OF EVIDENCE: 2 Technical Efficacy Stage 5 J. Magn. Reson. Imaging 2019;49:466-477.