Arterial Spin-Labeling in the Assessment of Pediatric Nontraumatic Orbital Lesions.

Benign and malignant pediatric orbital lesions can sometimes have overlapping features on conventional MR imaging sequences. MR imaging of 27 children was retrospectively reviewed to describe the signal of some common pediatric extraocular orbital lesions on arterial spin-labeling and to evaluate whether this sequence helps to discriminate malignant from benign masses, with or without ADC value measurements. Qualitative and quantitative assessments of arterial spin-labeling CBF and ADC were performed. All lesions were classified into 3 arterial spin-labeling perfusion patterns: homogeneous hypoperfusion (pattern 1, n = 15; benign lesions), heterogeneous hyperperfusion (pattern 2, n = 9; cellulitis, histiocytosis, malignant tumors), and homogeneous intense hyperperfusion (pattern 3, n = 3; infantile hemangiomas). Arterial spin-labeling can be a valuable tool to improve the diagnostic confidence of some orbital lesions, including infantile hemangioma. An algorithm is proposed.

Severe atypical Lemierre syndrome caused by methicillin-sensitive Staphylococcus aureus: Two pediatric case reports.

BACKGROUND: Lemierre syndrome is typically associated with ear, nose, and throat (ENT) infections caused by Fusobacterium necrophorum. Since 2002, cases of atypical Lemierre-like syndrome secondary to Staphylococcus aureus have been reported. CASES: We report two pediatric cases of atypical Lemierre syndrome with a similar presentation: exophthalmia, absence of pharyngitis, metastatic lung infection, and intracranial venous sinus thrombosis. Both patients had a favorable outcome following treatment with antibiotics, anticoagulation, and corticosteroids. CONCLUSION: Regular therapeutic monitoring of antibiotic levels helped to optimize antimicrobial treatment in both cases.

Arterial Spin-Labeling Perfusion Imaging in the Early Stage of Sturge-Weber Syndrome.

BACKGROUND AND PURPOSE: Sturge-Weber syndrome is a rare congenital neuro-oculo-cutaneous disorder. Although the principal mechanism of Sturge-Weber syndrome is characterized by a leptomeningeal vascular malformation, few data regarding perfusion abnormalities of the brain parenchyma are available. Therefore, the aim of this study was to assess the diagnostic performance of arterial spin-labeling perfusion imaging in the early stage of Sturge-Weber syndrome before 1 year of age until 3.5 years of age. We hypothesized that a leptomeningeal vascular malformation has very early hypoperfusion compared with controls with healthy brains. MATERIALS AND METHODS: We compared the CBF using arterial spin-labeling perfusion imaging performed at 3T MR imaging in the brain parenchymal regions juxtaposing the leptomeningeal vascular malformation in patients with Sturge-Weber syndrome (n = 16; 3.5 years of age or younger) with the corresponding areas in age-matched controls with healthy brains (n = 58). The analysis was performed following two complementary methods: a whole-brain voxel-based analysis and a visual ROI analysis focused on brain territory of the leptomeningeal vascular malformation. RESULTS: Whole-brain voxel-based comparison revealed a significant unilateral decrease in CBF localized in the affected cortices of patients with Sturge-Weber syndrome (P < .001). CBF values within the ROIs in patients with Sturge-Weber syndrome were lower than those in controls (in the whole cohort: median, 25 mL/100g/min, versus 44 mL/100g/min; P < .001). This finding was also observed in the group younger than 1 year of age, emphasizing the high sensitivity of arterial spin-labeling in this age window in which the diagnosis is difficult. CONCLUSIONS: Arterial spin-labeling perfusion imaging in the early stage of Sturge-Weber syndrome can help to diagnose the disease by depicting a cortical hypoperfusion juxtaposing the leptomeningeal vascular malformation.

Infant botulism: Report of a misleading case and important key messages.

Infant botulism is a rare and life-threatening disease caused by the inhalation of Clostridium botulinum spores and differs from adult forms. We report the case of infant botulism in a 4-month-old boy who was exclusively breastfed without any consumption of honey. He presented with severe and acute encephalo-myelo-radiculitis. The patient was treated without success for suspected "postviral" central nervous system inflammatory disease. The diagnosis was eventually made 20 days after the onset of symptoms on the basis of a stool sample. Recovery was complete. Infant botulism should be suspected when infants present with acute flaccid paralysis or brainstem weakness and specific immunoglobulins should be administered.

Imaging Features with Histopathologic Correlation of CNS High-Grade Neuroepithelial Tumors with a BCOR Internal Tandem Duplication.

BACKGROUND AND PURPOSE: A new brain tumor entity occurring in early childhood characterized by a somatic BCL6 corepressor gene internal tandem duplication was recently described. The aim of this study was to describe the radiologic pattern of these tumors and correlate this pattern with histopathologic findings. MATERIALS AND METHODS: This retrospective, noninterventional study included 10 children diagnosed with a CNS tumor, either by ribonucleic acid-sequencing analysis or deoxyribonucleic acid methylation analysis. Clinical, radiologic, and histopathologic data were collected. A neuropathologist reviewed 9 tumor samples. Preoperative images were analyzed in consensus by 7 pediatric radiologists. RESULTS: All tumors were relatively large (range, 4.7-9.2 cm) intra-axial peripheral masses with well-defined borders and no peritumoral edema. All tumors showed mild and heterogeneous enhancement and marked restriction on DWI of the solid portions. Perfusion imaging showed a relatively lower CBF in the tumor than in the adjacent normal parenchyma. Nine of 10 tumors showed areas of necrosis, with the presence of hemorrhage in 8/10 and calcifications in 4/7. Large intratumoral macroscopic veins were observed in 9/10 patients. No intracranial or spinal leptomeningeal dissemination was noted at diagnosis. CONCLUSIONS: CNS tumors with a BCL6 corepressor gene internal tandem duplication present as large intra-axial peripheral masses with well-defined borders, no edema, restricted diffusion, weak contrast enhancement, frequent central necrosis, hemorrhage and calcifications, intratumoral veins, and no leptomeningeal dissemination at the time of diagnosis. Knowledge of these imaging characteristics may aid in histologic, genomic, and molecular profiling of brain tumors in young children.

Spectrum of Neuroradiologic Findings Associated with Monogenic Interferonopathies.

The genetic interferonopathies are a heterogeneous group of disorders thought to be caused by the dysregulated expression of interferons and are now commonly considered in the differential diagnosis of children presenting with recurrent or persistent inflammatory phenotypes. With emerging therapeutic options, recognition of these disorders is increasingly important, and neuroimaging plays a vital role. In this article, we discuss the wide spectrum of neuroradiologic features associated with monogenic interferonopathies by reviewing the literature and illustrate these with cases from our institutions. These cases include intracerebral calcifications, white matter T2 hyperintensities, deep WM cysts, cerebral atrophy, large cerebral artery disease, bilateral striatal necrosis, and masslike lesions. A better understanding of the breadth of the neuroimaging phenotypes in conjunction with clinical and laboratory findings will enable earlier diagnosis and direct therapeutic strategies.

Focal Areas of High Signal Intensity in Children with Neurofibromatosis Type 1: Expected Evolution on MRI.

BACKGROUND AND PURPOSE: Focal areas of high signal intensity are T2WI/T2-FLAIR hyperintensities frequently found on MR imaging of children diagnosed with neurofibromatosis type 1, often thought to regress spontaneously during adolescence or puberty. Due to the risk of tumor in this population, some focal areas of high signal intensity may pose diagnostic problems. The objective of this study was to assess the characteristics and temporal evolution of focal areas of high signal intensity in children with neurofibromatosis type 1 using long-term follow-up with MR imaging. MATERIALS AND METHODS: We retrospectively examined the MRIs of children diagnosed with neurofibromatosis type 1 using the National Institutes of Health Consensus Criteria (1987), with imaging follow-up of at least 4 years. We recorded the number, size, and surface area of focal areas of high signal intensity according to their anatomic distribution on T2WI/T2-FLAIR sequences. A generalized mixed model was used to analyze the evolution of focal areas of high signal intensity according to age, and separate analyses were performed for girls and boys. RESULTS: Thirty-nine patients (ie, 285 MR images) with a median follow-up of 7 years were analyzed. Focal areas of high signal intensity were found in 100% of patients, preferentially in the infratentorial white matter (35% cerebellum, 30% brain stem) and in the capsular lenticular region (22%). They measured 15 mm in 95% of cases. They appeared from the age of 1 year; increased in number, size, and surface area to a peak at the age of 7; and then spontaneously regressed by 17 years of age, similarly in girls and boys. CONCLUSIONS: Focal areas of high signal intensity are mostly small (<15 mm) abnormalities in the posterior fossa or capsular lenticular region. Our results suggest that the evolution of focal areas of high signal intensity is not related to puberty with a peak at the age of 7 years. Knowledge of the predictive evolution of focal areas of high signal intensity is essential in the follow-up of children with neurofibromatosis type 1.

Incidental Brain MRI Findings in Children: A Systematic Review and Meta-Analysis.

BACKGROUND: The detection of incidental findings on children's brain MR imaging poses various practical issues because the life-long implications of such findings may be profound. PURPOSE: Our aim was to assess the prevalence and characteristics of incidental brain MR imaging findings in children. DATA SOURCES: Electronic databases (PubMed, EMBASE, and Cochrane) were searched for articles published between 1985 to July 2018, with the following search terms: "incidental," "findings," "brain," "MR imaging." STUDY SELECTION: Inclusion criteria were the following: 1) patients younger than 21 years of age, 2) healthy children without any clinical condition, 3) MR images obtained with at least a 1.5T magnet, 4) original articles, and 5) a methodologic quality score of ≥10. DATA ANALYSIS: Two observers independently extracted data and assessed data quality and validity. The number and type of incidental findings were pooled. Heterogeneity was assessed using the Cochran Q statistic and the I2 statistic. DATA SYNTHESIS: Seven studies were included, reporting 5938 children (mean age, 11.3 ± 2.8 years). Incidental findings were present in 16.4% (99% CI, 9.8-26.2; Q = 117.5, I2= 94.9%) of healthy children, intracranial cysts being the most frequent (10.2%, 99% CI, 3.1-28.5; Q = 306.4, I2 = 98.0%). Nonspecific white matter hyperintensities were reported in 1.9% (99% CI, 0.2-16.8; Q = 73.6, I2 = 94.6%), Chiari 1 malformation was found in 0.8% (99% CI, 0.5-1.3; Q = 7.6, I2 = 60.5%), and intracranial neoplasms were reported in 0.2% (99% CI, 0.1-0.6; Q = 3.4, I2 = 12.3%). In total, the prevalence of incidental findings needing follow-up was 2.6% (99% CI, 0.5-11.7; Q = 131.2, I2 = 95.4%). Incidental findings needing specific treatment were brain tumors (0.2%) and cavernomas (0.2%). LIMITATIONS: Limitations were no age stratification or ethnicity data and variation in the design of included studies. CONCLUSIONS: The prevalence of incidental findings is much more frequent in children than previously reported in adults, but clinically meaningfull incidental findings were present in <1 in 38 children.

CT and Multimodal MR Imaging Features of Embryonal Tumors with Multilayered Rosettes in Children.

BACKGROUND AND PURPOSE: Embryonal tumors with multilayered rosettes, C19MC-altered, are brain tumors occurring in young children, which were clearly defined in the 2016 World Health Organization classification of central nervous system neoplasms. Our objective was to describe the multimodal imaging characteristics of this new entity. MATERIALS AND METHODS: We performed a retrospective monocentric review of embryonal brain tumors and looked for embryonal tumors with multilayered rosettes with confirmed C19MC alteration. We gathered morphologic imaging data, as well as DWI and PWI data (using arterial spin-labeling and DSC). RESULTS: We included 16 patients with a median age of 2 years 8 months. Tumors were both supratentorial (56%, 9/16) and infratentorial (44%, 7/16). Tumors were large (median diameter, 59 mm; interquartile range, 48-71 mm), with absent (75%, 12/16) or minimal (25%, 4/16) peritumoral edema. Enhancement was absent (20%, 3/15) or weak (73%, 11/15), whereas intratumoral macrovessels were frequently seen (94%, 15/16) and calcifications were present in 67% (10/15). Diffusion was always restricted, with a minimal ADC of 520 mm2/s (interquartile range, 495-540 mm2/s). Cerebral blood flow using arterial spin-labeling was low, with a maximal CBF of 43 mL/min/100 g (interquartile range, 33-55 mL/min/100 g 5). When available (3 patients), relative cerebral blood volume using DSC was high (range, 3.5-5.8). CONCLUSIONS: Embryonal tumors with multilayered rosettes, C19MC-altered, have characteristic imaging features that could help in the diagnosis of this rare tumor in young children.

A direct multi-volume rendering method aiming at comparisons of 3-D images and models.

We present a new method for direct volume rendering of multiple three-dimensional (3-D) functions using a density emitter model. This work aims at obtaining visual assessment of the results of a 3-D image registration algorithm which operates on anisotropic and non segmented medical data. We first discuss the fundamentals associated with direct, simultaneous rendering of such datasets. Then, we recall the fuzzy classification and fuzzy surface rendering theory within the density emitter model terminology, and propose an extension of standard direct volume rendering that can handle the rendering of two or more 3-D functions; this consists of the definition of merging rules that are applied on emitter clouds. The included rendering applications are related on one hand, to volume-to-volume registration, and on the other hand, to surface-to-volume registration: the first case is concerned with global elastic registration of CT data, and the second one presents fitting of an implicit surface over a CT data subset. In these two medical imaging application cases, our rendering scheme offers a comprehensive appreciation of the relative position of structural information.

Continuous monitoring of uterine contractions to control intra-amniotic administration of prostaglandin F2 alpha for therapeutic and missed abortion.

Intra-amniotic prostaglandin F2 alpha (PGF2 alpha) was administered to 10 patients for midtrimester therapeutic abortion and to 20 patients for missed abortion. An epidural catheter was placed into the amniotic cavity and the other end was connected to a physiological pressure transducer to measure the uterine contractions continuously. The dosage was adjusted according to the uterine contractions, and was therefore individualized for each patient. Half the patients with therapeutic abortion required PGF2 alpha 30 mg or less, and only 20% of patients with missed abortion needed more than 30 mg. Complications such as uterine cervical lacerations could be prevented by administration of the correct dosage of prostaglandin in each case.