Time-resolved contrast-enhanced MRA (TWIST) with gadofosveset trisodium in the classification of soft-tissue vascular anomalies in the head and neck in children following updated 2014 ISSVA classification: first report on systematic evaluation of MRI and TWIST in a cohort of 47 children.

AIM: To evaluate the relative accuracy of contrast-enhanced time-resolved angiography with interleaved stochastic trajectories versus conventional contrast-enhanced magnetic resonance imaging (MRI) following International Society for the Study of Vascular Anomalies updated 2014-based classification of soft-tissue vascular anomalies in the head and neck in children. MATERIALS AND METHODS: Time-resolved angiography with interleaved stochastic trajectories versus conventional contrast-enhanced MRI of children with diagnosis of soft-tissue vascular anomalies in the head and neck referred for MRI between 2008 and 2014 were retrospectively reviewed. Forty-seven children (0-18 years) were evaluated. Two paediatric neuroradiologists evaluated time-resolved MRA and conventional MRI in two different sessions (30 days apart). Blood-pool endovascular MRI contrast agent gadofosveset trisodium was used. RESULTS: The present cohort had the following diagnoses: infantile haemangioma (n=6), venous malformation (VM; n=23), lymphatic malformation (LM; n=16), arteriovenous malformation (AVM; n=2). Time-resolved MRA alone accurately classified 38/47 (81%) and conventional MRI 42/47 (89%), respectively. Although time-resolved MRA alone is slightly superior to conventional MRI alone for diagnosis of infantile haemangioma, conventional MRI is slightly better for diagnosis of venous and LMs. Neither time-resolved MRA nor conventional MRI was sufficient for accurate diagnosis of AVM in this cohort. Conventional MRI combined with time-resolved MRA accurately classified 44/47 cases (94%). CONCLUSION: Time-resolved MRA using gadofosveset trisodium can accurately classify soft-tissue vascular anomalies in the head and neck in children. The addition of time-resolved MRA to existing conventional MRI protocols provides haemodynamic information, assisting the diagnosis of vascular anomalies in the paediatric population at one-third of the dose of other MRI contrast agents.

Common Neuroimaging Findings in Bosch-Boonstra-Schaaf Optic Atrophy Syndrome.

Bosch-Boonstra-Schaaf optic atrophy syndrome (BBSOAS) is a rare autosomal dominant syndrome secondary to mutations in NR2F1 (COUP-TF1), characterized by visual impairment secondary to optic nerve hypoplasia and/or atrophy, developmental and cognitive delay, and seizures. This study reports common neuroimaging findings in a cohort of 21 individuals with BBSOAS that collectively suggest the diagnosis. These include mesial temporal dysgyria, perisylvian dysgyria, posterior predominant white matter volume loss, callosal abnormalities, lacrimal gland abnormalities, and optic nerve volume loss.

Medullary Tegmental Cap Dysplasia: Fetal and Postnatal Presentations of a Unique Brainstem Malformation.

BACKGROUND AND PURPOSE: Medullary tegmental cap dysplasia is a rare brainstem malformation, first described and defined by James Barkovich in his book Pediatric Neuroimaging from 2005 as an anomalous mass protruding from the posterior medullary surface. We describe the neuroimaging, clinical, postmortem, and genetic findings defining this unique malformation. MATERIALS AND METHODS: This is a multicenter, international, retrospective study. We assessed the patients' medical records, prenatal ultrasounds, MR images, genetic findings, and postmortem results. We reviewed the medical literature for all studies depicting medullary malformations and evaluated cases in which a dorsal medullary protuberance was described. RESULTS: We collected 13 patients: 3 fetuses and 10 children. The medullary caps had multiple characteristics. Associated brain findings were a rotated position of the medulla, a small and flat pons, cerebellar anomalies, a molar tooth sign, and agenesis of the corpus callosum. Systemic findings included the following: polydactyly, hallux valgus, large ears, and coarse facies. Postmortem analysis in 3 patients revealed that the cap contained either neurons or white matter tracts. We found 8 publications describing a dorsal medullary protuberance in 27 patients. The syndromic diagnosis was Joubert-Boltshauser syndrome in 11 and fibrodysplasia ossificans progressiva in 14 patients. CONCLUSIONS: This is the first study to describe a series of 13 patients with medullary tegmental cap dysplasia. The cap has different shapes: distinct in Joubert-Boltshauser syndrome and fibrodysplasia ossificans progressive. Due to the variations in the clinical, imaging, and postmortem findings, we conclude that there are multiple etiologies and pathophysiology. We suggest that in some patients, the pathophysiology might be abnormal axonal guidance.

Susceptibility weighted imaging of the neonatal brain.

Susceptibility weighted imaging (SWI) is a well-established magnetic resonance technique, which is highly sensitive for blood, iron, and calcium depositions in the brain and has been implemented in the routine clinical use in both children and neonates. SWI in neonates might provide valuable additional diagnostic and prognostic information for a wide spectrum of neonatal neurological disorders. To date, there are few articles available on the application of SWI in neonatal neurological disorders. The purpose of this article is to illustrate and describe the characteristic SWI findings in various typical neonatal neurological disorders.

Diagnostic Accuracy of MRI for Detection of Meningitis in Infants.

PURPOSE: To determine the accuracy of MR imaging for diagnosis of meningitis in infants. MATERIALS AND METHODS: Retrospective review of infants less than 1 year of age who underwent a brain MR imaging for meningitis from 2010-2018. Gold standard for diagnosis of bacterial meningitis was a positive bacterial CSF culture or a positive blood culture with an elevated CSF WBC count, and diagnosis of viral meningitis was a positive CSF PCR result and elevated CSF WBC count. Sensitivity, specificity, PPV, NPV, and accuracy for MR imaging diagnosis of meningitis were calculated. RESULTS: Two hundred nine infants with mean age 80 days (range 0-347 days) were included. There were 178 true positives with the most common pathogens being: Group B Streptococcus (58), E. coli (50), Streptococcus pneumoniae (21), H. influenzae (4); Herpes simplex virus 1 or 2 (18); Enterovirus (4); and other (23). There were 31 true negatives. Range of sensitivity, specificity, PPV, NPV, and accuracy of MR imaging for detection of meningitis was 67.4-83.5%, 92.3-95.7%, 95.0-98.6%, 33.3-76.5%, and 71.3-86.5% respectively. MR imaging sensitivity decreased after 10 days from time of presentation while specificity remained stable. Among individual MR imaging findings, leptomeningeal enhancement was the most sensitive finding, while cerebritis, infarction, ventriculitis, abscess, and intraventricular purulent material were the most specific findings. CONCLUSIONS: MR imaging of the brain demonstrates high specificity and moderate sensitivity for diagnosis among infants presenting with signs and symptoms of meningitis. The results reflect current standard of care for imaging of infants with meningitis however a selection bias for imaging of more severe meningitis may affect these results.

An In-Depth Analysis of Brain and Spine Neuroimaging in Children with Abusive Head Trauma: Beyond the Classic Imaging Findings.

BACKGROUND AND PURPOSE: Abusive head trauma is the leading cause of morbidity and mortality in young children. Radiology provides valuable information for this challenging diagnosis, but no single neuroimaging finding is independently diagnostic of abusive head trauma. Our purposes were to describe the prevalence of brain and spine neuroimaging findings and to analyze the association of neuroimaging findings with clinical factors to determine which neuroimaging findings may be used as prognostic indicators. MATERIALS AND METHODS: Children with a confirmed abusive head trauma diagnosis between January 2018 to February 2021 were included in this single-center retrospective study. Patient demographics, survival, Glasgow Coma Scale score on admission, length of hospital stay, and intensive care unit stay were examined. Brain neuroimaging findings were categorized as classic and nonclassic findings. Spine MRIs were also assessed for spinal ligamentous injury, compression fracture, and hemorrhage. The χ2 test or the Wilcoxon rank-sum test was used for the analysis. RESULTS: One hundred two children (male/female ratio: 75:27; average age, 9.49; range, 0.27-53.8 months) were included. Subdural hematoma was the most common (83.3%) classic neuroimaging finding. Bridging vein thrombosis was the most common (30.4%) nonclassic neuroimaging finding. Spinal ligamentous injury was seen in 23/49 patients. Hypoxic-ischemic injury was significantly higher in deceased children (P = .0001). The Glasgow Coma Scale score was lower if hypoxic-ischemic injury (P < .0001) or spinal ligamentous injury were present (P = .017). The length of hospital stay was longer if intraventricular hemorrhage (P = .04), diffuse axonal injury (P = .017), hypoxic-ischemic injury (P = .001), or arterial stroke (P = .0003) was present. The intensive care unit stay was longer if intraventricular hemorrhage (P = .02), diffuse axonal injury (P = .01), hypoxic-ischemic injury (P < .0001), or spinal ligamentous injury (P = .03) was present. CONCLUSIONS: Our results may suggest that a combination of intraventricular hemorrhage, diffuse axonal injury, hypoxic-ischemic injury, arterial stroke, and/or spinal ligamentous injury on neuroimaging at presentation may be used as potential poor prognostic indicators in children with abusive head trauma.

Imaging Findings in Children Presenting with CNS Nelarabine Toxicity.

Nelarabine is a nucleoside analog critical for the treatment of patients with T-cell acute lymphoblastic leukemia/lymphoma. However, clinical peripheral and central neurologic adverse events associated with nelarabine administration have been reported. Neuroimaging of brain neurotoxicity has only been described in very few reports in pediatric patients so far. Six children with diagnosed T-cell acute lymphoblastic leukemia who clinically experienced possible, probable, or definite nelarabine-induced toxicity and underwent spine and/or brain MR imaging were reviewed. Neuroimaging findings showed a mixture of patterns including features of acute toxic leukoencephalopathy (seen in 6 cases), posterior reversible encephalopathy syndrome (2 cases), involvement of deep gray structures (1 case) and brainstem (2 cases), cranial and spinal neuropathy (2 cases each), and myelopathy (2 cases). Even though neuroimaging findings are nonspecific, the goal of this article was to alert the pediatric neuroradiologists, radiologists, and clinicians about the possibility of nelarabine-induced neurotoxicity and its broad neuroimaging spectrum.

Neuroimaging in Pediatric Patients with Juvenile Xanthogranuloma of the CNS.

BACKGROUND AND PURPOSE: Juvenile xanthogranuloma is a rare clonal, myeloid, neoplastic disorder. Typically, juvenile xanthogranuloma is a self-limited disorder of infancy, often presenting as a solitary red-brown or yellow skin papule/nodule. A small subset of patients present with extracutaneous, systemic juvenile xanthogranuloma, which may include the CNS. The goal of this retrospective study was to evaluate and categorize the neuroimaging findings in a representative cohort of pediatric patients with CNS juvenile xanthogranuloma. MATERIALS AND METHODS: The brain and/or spine MR imaging data of 14 pediatric patients with pathology-proven juvenile xanthogranuloma were categorized and evaluated for the location; the signal intensity of xanthogranulomas on T1WI, T2WI, DWI, and a matching ADC map for the pattern and degree of contrast enhancement; and the presence of perilesional edema, cysts, or necrosis. RESULTS: Fourteen pediatric patients (8 girls, 6 boys; mean age, 84 months) were included in the study. Patients presented with a wide variety of different symptoms, including headache, seizure, ataxia, strabismus, hearing loss, facial paresis, and diabetes insipidus. Juvenile xanthogranuloma lesions were identified in a number of different sites, including supra- and infratentorial as well as intracranial and spinal leptomeningeal. Five patients were categorized into the neuroradiologic pattern unifocal CNS juvenile xanthogranuloma; 8, into multifocal CNS juvenile xanthogranuloma; and 1, into multifocal CNS juvenile xanthogranuloma with intracranial and spinal leptomeningeal disease. In most cases, xanthogranulomas were small-to-medium intra-axial masses with isointense signal on T1WI (compared with cortical GM), iso- or hyperintense signal on T2WI, had restricted diffusion and perilesional edema. Almost all xanthogranulomas showed avid contrast enhancement. However, we also identified less common patterns with large lesions, nonenhancing lesions, or leptomeningeal disease. Four cases had an additional CT available. On CT, all xanthogranulomas were homogeneously hyperdense (solid component) without evident calcifications. CONCLUSIONS: CNS juvenile xanthogranuloma may demonstrate heterogeneous neuroimaging appearances potentially mimicking other diseases, such as primary brain neoplasms, metastatic disease, lymphoma and leukemia, other histiocytic disorders, infections, or granulomatous diseases.

Leukoencephalopathy with vanishing white matter: serial MRI of the brain and spinal cord including diffusion tensor imaging.

Vanishing white matter disease (VWM) is one of the most frequent inherited childhood white matter disorders. We present the brain and spinal cord disease progression on serial conventional magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI) in a 4-year-old boy. Consecutive MRI examinations demonstrated a progression of the signal abnormalities in the cerebral white matter. Globally, apparent diffusion coefficient (ADC) values as well as axial and radial diffusivity increased over time, while fractional anisotropy (FA) values decreased. Involvement of the cervical posterior spinal tracts and mild global spinal cord atrophy was found. In conclusion, serial MRI and DTI studies may help to better understand the selective injury of the myelin and axons in VWM disease. These data may help in monitoring disease progression. Our data also show that complete neuroimaging work-up in VWM should also include the spinal cord.

Prenatal MR diffusion tractography in a fetus with complete corpus callosum agenesis.

Diffusion tensor imaging (DTI) in combination with 3D-tractography reconstructions allows studying the neuro-architecture of complex brain malformations in vivo. Prenatal, in utero DTI has been limited by long acquisition times, poor signal to noise ratio and multiple artifacts. Recent developments in hard- and software allow collection of high quality DTI data sets in utero. We report on the DTI and tractography data of a fetus with a corpus callosum agenesis. Our case shows that nowadays the neuro-architecture of the fetal brain can be studied in excellent detail. Prenatal DTI and tractography may help to improve our understanding of complex brain malformations.

Tecto-cerebellar dysraphism with occipital encephalocele: not a distinct disorder, but part of the Joubert syndrome spectrum?

Magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI) findings in a 4-year-old child with occipital encephalocele, cerebellar vermis hypogenesis, and tectal malformation are presented. The neuroimaging findings are reminiscent of tectocerebellar dysraphism with an occipital encephalocele (TCD-OE). Additionally, elongated, thickened, and horizontally orientated superior cerebellar peduncles, an abnormally deepened interpeduncular fossa, subependymal heterotopia, and focal cortical dysplasia were noted. Color-coded fractional anisotropy (FA) maps revealed an absence of the decussation of the superior cerebellar peduncles. These findings are highly suggestive of Joubert syndrome and related disorders (JSRD). Our report and the review of the published cases suggest that TCD-OE is not a nosological entity, but may represent the structural manifestation of heterogeneous disorders such as the JSRD spectrum. DTI may be very helpful to differentiate between similar midbrain-hindbrain malformations.

Inferior pontine segmentation abnormality in a child with sensorineural deafness: DTI analysis of fiber tracts.

MRI/DTI data are presented in a child with sensoneurinal hearing loss and swallowing disorder. MRI/DTI revealed hypoplastic 8th cranial nerves and an inferior pontine segmentation abnormality. Color-coded FA-maps revealed diminished/absent fiber tracts within the affected brainstem segment. This report may add another small puzzle piece to the ongoing research on brainstem malformations.

Susceptibility-weighted imaging (SWI): a potential non-invasive imaging tool for characterizing ischemic brain injury?

Susceptibility-weighted imaging (SWI) is a new high-resolution magnetic resonance imaging (MRI) tool that uses the paramagnetic susceptibility effects of deoxygenated blood to study the intracranial venous vasculature. We present SWI imaging findings in two children who suffered from acute arterial ischemia. Various patterns of normal/altered venous drainage could be identified. Our case study suggests that SWI assisted mapping of the regional changes of the cerebral venous drainage and correlation with diffusion weighted MRI may identify critically perfused brain at risk for infarct progression. Prospective studies are mandatory to further validate the value of SWI.

Neuroimaging Offers Low Yield in Children Positive for SARS-CoV-2.

The coronavirus disease 2019 (COVID-19) pandemic caused by Severe Acute Respiratory Syndrome coronavirus disease 2 (SARS CoV-2) most commonly presents with respiratory disease, but neurologic complications are being reported. We aimed to investigate the rate of positive neuroimaging findings in children positive for SARS-CoV-2 referred for neuroimaging between March 18 and September 30, 2020. We found that 10% (n = 2) had acute findings. Our results may suggest that in children, neurologic involvement in COVID-19 is rare, neuroimaging has a low yield in diagnosis, and acute neuroimaging should involve careful risk-benefit analysis.

Can MRI Differentiate between Infectious and Immune-Related Acute Cerebellitis? A Retrospective Imaging Study.

BACKGROUND AND PURPOSE: Acute cerebellitis is an acute neurologic condition attributable to a recent or concurrent infection or a recent vaccination or ingestion of medication, with MR imaging evidence of cerebellar edema. MR imaging can confirm an anatomic abnormality and may allow the radiologist to establish a differential diagnosis. The purpose of this research was to evaluate the MR imaging findings in children with acute cerebellitis due to infectious versus immune-related conditions, in particular whether MR imaging findings allow differentiation. MATERIALS AND METHODS: Electronic medical records were reviewed between 2003 and 2020 in our quaternary children's hospital. Data included demographics and clinical records: presentation/symptoms, final diagnosis including acute cerebellitis and immune-related acute cerebellitis, length of stay, treatment, condition at discharge, and laboratory findings. Retrospective independent review of all brain MR imaging studies was performed. RESULTS: Forty-three patients (male/female ratio, 28:15) were included in this study. Average age at presentation was 7.08 years (range, 0.05-17.52 years). Thirty-five children had infectious and 8 children had immune-related acute cerebellitis. Significant differences in neuroimaging were the following: 1) T2-FLAIR hyperintense signal in the brainstem (37.50% versus 2.85%, P = .016); 2) T2-FLAIR hyperintense signal in the supratentorial brain higher in the immune-related group (37.50% versus 0.00%, P = .004); and 3) downward herniation, higher in the infectious acute cerebellitis group (42.85% versus 0.00%, P = .03). CONCLUSIONS: Acute cerebellitis is a rare condition, and MR imaging is helpful in the differential diagnosis. T2-FLAIR hyperintense signal in the brainstem and supratentorial brain may be indicative of immune-related acute cerebellitis, and downward herniation may be indicative of infectious acute cerebellitis.

Neuroimaging Features of Ectopic Cerebellar Tissue: A Case Series Study of a Rare Entity.

Ectopic cerebellar tissue is a rare entity likely secondary to multiple, interacting, developmental errors during embryogenesis. Multiple sites of ectopic cerebellar tissue have been reported, including extracranial locations; however, an intracranial location is most common. We report on the MR imaging findings of a multi-institutional series of 7 ectopic cerebellar tissue cases (2 males, 4 females, 1 fetal) ranging from 22 weeks 5 days' gestational age to 18 years of age. All cases of ectopic cerebellar tissue were diagnosed incidentally, while imaging was performed for other causes. Ectopic cerebellar tissue was infratentorial in 6/7 patients and supratentorial in 1/7 patients. All infratentorial ectopic cerebellar tissue was connected with the brain stem or cerebellum. MR imaging signal intensity was identical to the cerebellar gray and white matter signal intensity on all MR imaging sequences in all cases. Ectopic cerebellar tissue should be considered in the differential diagnoses of extra-axial masses with signal characteristics similar to those of the cerebellum. Surgical biopsy or resection is rarely necessary, and in most cases, MR imaging is diagnostic.

Postnatal in-vivo MRI findings in anencephaly.

We report on the MRI findings of an anencephalic infant who survived 10 weeks postnatally. MRI showed absence of the cranial vault, all supratentorial structures, and the cerebellum. A brainstem primordium without pontine prominence was present. The brainstem was surrounded by the area cerebrovasculosa. The absence of a pontine prominence in an anencephalic infant without cerebellar tissue supports the hypothesis that absent pontine prominence is found in children with a prenatal loss of cerebellar tissue.

Cerebellar abnormality in children and young adults with tuberous sclerosis complex: MR and diffusion weighted imaging findings.

OBJECTIVES: The goal of our study was to: determine the incidence of cerebellar lesions in a cohort of children and young adults with TSC, and analyze the magnetic resonance imaging (MRI) findings of cerebellar TSC lesions including their contrast behavior and diffusion characteristics. MATERIAL AND METHODS: MRI studies of 27 TSC patients (mean age, 10.6 years) were evaluated for: cortical/subcortical tubers, white matter lesions, subependymal nodules, and giant cell astrocytomas. Patients with cerebellar involvement were further analyzed for the imaging and diffusion characteristics. ADC measurements of the cerebellar tubers were performed and compared with the contralateral normal appearing cerebellum. The clinical charts were revisited for symptoms suggesting cerebellar involvement. RESULTS: Cerebellar tubers were seen in 8/27 patients, cerebellar atrophy in 1/27 patients. Cerebellar tubers showed a pyramidal/wedge appearance with a broad base reaching the cortex. The majority of the cerebellar tubers (11/12, 92%) showed a "zebra-like" contrast enhancement. All cerebellar tubers had increased ADC values (mean ADC 1472×10(-6) mm(2)/s). None of the patients had "typical" cerebellar symptoms. CONCLUSION: Thirty-three percent of TSC patients had cerebellar lesions, most of them being cerebellar tubers. Cerebellar tubers differ from supratentorial tubers both concerning shape and contrast behavior. The exact etiology of contrast enhancement remains unclear. Future studies have to determine the impact of cerebellar lesions on neurocognitive development.

MRI with diffusion-weighted imaging in children and young adults with simultaneous supra- and infratentorial manifestations of Sturge-Weber syndrome.

BACKGROUND AND PURPOSE: Patients with Sturge-Weber syndrome (SWS) may present with neurological symptoms or neurocognitive deficits that cannot always be explained by the supratentorial findings seen on conventional MRI. Purpose of our study was to determine (a) what percentage of children with SWS have simultaneous supra- and infratentorial involvement and (b) what kind of infratentorial lesions are seen. In addition, we used DWI data to measure the ADC-values of normal appearing white matter (NAWM) to rule out impaired or delayed white matter maturation. MATERIAL AND METHODS: Fifteen SWS patients who underwent MRI/DWI between January 2000 and August 2008 were studied. Images were retrospectively reviewed by two experienced pediatric neuroradiologists. ADC measurements of the NAWM were performed at multiple locations within the brain. ADC-values were compared with normative data and with 18 matched normal controls from our hospital. RESULTS: Infratentorial involvement was seen in six out of 15 patients (40%). Cerebellar lesions included leptomeningeal enhancement, atrophy and developmental venous anomaly. ADC-values were increased in the NAWM of the frontal, parietal and occipital lobes of both hemispheres and in the pons. The ADC-values of the cerebellar white matter were increased in six out of eight affected cerebellar lobes. CONCLUSION: Infratentorial involvement of SWS is more frequently than previously thought. ADC analysis of the NAWM reveals impaired/altered white matter maturation distant from the area of leptomeningeal angiomatosis. This may explain neurocognitive deficits. ADC analysis of the NAWM may serve as biomarker of tissue injury and therefore guide treatment options.

Design of 3D-Printed Nasopharyngeal Swabs for Children is Enabled by Radiologic Imaging.

3D-printed nasopharyngeal swabs for COVID-19 molecular diagnostic testing address the national shortage of swabs. Swab designs for adult use were placed in the public domain in March 2020. Swabs for pediatric use, however, need to be smaller and more flexible to navigate delicate pediatric nasopharyngeal cavities. We describe a novel use of maxillofacial CT scans to aid in the design of pediatric nasopharyngeal swabs.