More than 50 million people worldwide sustain a traumatic brain injury (TBI) annually. Detection of intracranial injuries relies on head CT, which is overused and resource intensive. Blood-based ...brain biomarkers hold the potential to predict absence of intracranial injury and thus reduce unnecessary head CT scanning. We sought to validate a test combining ubiquitin C-terminal hydrolase-L1 (UCH-L1) and glial fibrillary acidic protein (GFAP), at predetermined cutoff values, to predict traumatic intracranial injuries on head CT scan acutely after TBI.
This prospective, multicentre observational trial included adults (≥18 years) presenting to participating emergency departments with suspected, non-penetrating TBI and a Glasgow Coma Scale score of 9–15. Patients were eligible if they had undergone head CT as part of standard emergency care and blood collection within 12 h of injury. UCH-L1 and GFAP were measured in serum and analysed using prespecified cutoff values of 327 pg/mL and 22 pg/mL, respectively. UCH-L1 and GFAP assay results were combined into a single test result that was compared with head CT results. The primary study outcomes were the sensitivity and the negative predictive value (NPV) of the test result for the detection of traumatic intracranial injury on head CT.
Between Dec 6, 2012, and March 20, 2014, 1977 patients were recruited, of whom 1959 had analysable data. 125 (6%) patients had CT-detected intracranial injuries and eight (<1%) had neurosurgically manageable injuries. 1288 (66%) patients had a positive UCH-L1 and GFAP test result and 671 (34%) had a negative test result. For detection of intracranial injury, the test had a sensitivity of 0·976 (95% CI 0·931–0·995) and an NPV of 0·996 (0·987–0·999). In three (<1%) of 1959 patients, the CT scan was positive when the test was negative.
These results show the high sensitivity and NPV of the UCH-L1 and GFAP test. This supports its potential clinical role for ruling out the need for a CT scan among patients with TBI presenting at emergency departments in whom a head CT is felt to be clinically indicated. Future studies to determine the value added by this biomarker test to head CT clinical decision rules could be warranted.
Banyan Biomarkers and US Army Medical Research and Materiel Command.
Background
Longitudinal T2-hyperintense signal is commonly seen in the spinal cord of infants and likely reflects normal unmyelinated white matter tracts, but it can be mistaken for pathology. ...Autopsy studies have described incomplete myelination of spinal cord in early childhood; however, the maturation timeline of the spinal cord has not been described on imaging.
Objective
The purpose of this study was to retrospectively evaluate the maturation timeline of the spinal cord on MRI to provide a baseline for image interpretation.
Materials and methods
We retrospectively reviewed axial T2-W images of the spinal cord acquired on 1.5-tesla (T) and 3.0-T MRI in children ages 0–2 years for presence of longitudinal T2-hyperintense signal, and we subjectively graded this signal as 0 (absent) to 3 (pronounced). Further, we reviewed a summary of medical records for confounding pathology in the brain or spine. Cord signal was interpreted as normal in the clinical report by subspecialized pediatric neuroradiologists for all included children.
Results
We reviewed 437 MRI exams from 409 children and included 189 studies in the analysis. Longitudinal T2-hyperintense signal in the lateral cord was seen in 95% (19/20) of subjects <1 month of age and was not seen in subjects ages 21–24 months (0/15). Grade 3 signal was seen in 22% (11/50) of infants ages 0–2 months and was not seen infants older than 5 months.
Conclusion
Characteristic symmetrical longitudinal T2 hyperintensity in the lateral spinal cord is common in infants and should not be mistaken for pathology, and it was not seen in children older than 21 months.
Objective Small head circumferences and white matter injury in the form of periventricular leukomalacia have been observed in populations of infants with severe forms of congenital heart defects. ...This study tests the hypothesis that congenital heart defects delay in utero structural brain development. Methods Full-term infants with hypoplastic left heart syndrome or transposition of the great arteries were prospectively evaluated with preoperative brain magnetic resonance imaging. Patients with independent risk factors for abnormal brain development (shock, end-organ injury, or intrauterine growth retardation) were excluded. Outcome measures included head circumferences and the total maturation score on magnetic resonance imaging. Total maturation score is a previously validated semiquantitative anatomic scoring system used to assess whole brain maturity. The total maturation score evaluates 4 parameters of maturity: (1) myelination, (2) cortical infolding, (3) involution of glial cell migration bands, and (4) presence of germinal matrix tissue. Results The study cohort included 29 neonates with hypoplastic left heart syndrome and 13 neonates with transposition of the great arteries at a mean gestational age of 38.9 ± 1.1 weeks. Mean head circumference was 1 standard deviation below normal. The mean total maturation score for the cohort was 10.15 ± 0.94, significantly lower than reported normative data in infants without congenital heart defects, corresponding to a delay of 1 month in structural brain development. Conclusion Before surgery, term infants with hypoplastic left heart syndrome and transposition of the great arteries have brains that are smaller and structurally less mature than expected. This delay in brain development may foster susceptibility to periventricular leukomalacia in the preoperative, intraoperative, and postoperative periods.
Advanced magnetic resonance neuroimaging techniques play an important adjunct role to conventional MRI sequences for better depiction and characterization of a variety of brain disorders. In this ...article we briefly review the basic principles and clinical utility of a select number of these techniques, including clinical functional MRI for presurgical planning, clinical diffusion tensor imaging and related techniques, dynamic susceptibility contrast perfusion imaging using gadolinium injection, and arterial spin labeling perfusion imaging. The article focuses on general principles of clinical MRI acquisition protocols, relevant factors affecting image quality, and a general framework for obtaining images for each of these techniques. We also present relevant advances for acquiring these types of imaging sequences in a clinical setting.
An adolescent with plastic bronchitis due to congenital heart disease had altered mental status after an interventional lymphatic procedure in which lipiodol contrast was used. Neuroimaging revealed ...cerebral lipiodol embolization due to direct shunting between lymphatic channels and pulmonary veins. Cerebral lipiodol embolization is a potential neurologic morbidity associated with interventional lymphatic procedures.
The shortly upcoming 5th edition of the World Health Organization Classification of Tumors of the Central Nervous System is bringing extensive changes in the terminology of diffuse high-grade gliomas ...(DHGGs). Previously “glioblastoma,” as a descriptive entity, could have been applied to classify some tumors from the family of pediatric or adult DHGGs. However, now the term “glioblastoma” has been divested and is no longer applied to tumors in the family of pediatric types of DHGGs. As an entity, glioblastoma remains, however, in the family of adult types of diffuse gliomas under the insignia of “glioblastoma, IDH-wildtype.” Of note, glioblastomas still can be detected in children when glioblastoma, IDH-wildtype is found in this population, despite being much more common in adults. Despite the separation from the family of pediatric types of DHGGs, what was previously labeled as “pediatric glioblastomas” still remains with novel labels and as new entities. As a result of advances in molecular biology, most of the previously called “pediatric glioblastomas” are now classified in one of the four family members of pediatric types of DHGGs. In this review, the term glioblastoma is still apocryphally employed mainly due to its historical relevance and the paucity of recent literature dealing with the recently described new entities. Therefore, “glioblastoma” is used here as an umbrella term in the attempt to encompass multiple entities such as astrocytoma, IDH-mutant (grade 4); glioblastoma, IDH-wildtype; diffuse hemispheric glioma, H3 G34-mutant; diffuse pediatric-type high-grade glioma, H3-wildtype and IDH-wildtype; and high grade infant-type hemispheric glioma. Glioblastomas are highly aggressive neoplasms. They may arise anywhere in the developing central nervous system, including the spinal cord. Signs and symptoms are non-specific, typically of short duration, and usually derived from increased intracranial pressure or seizure. Localized symptoms may also occur. The standard of care of “pediatric glioblastomas” is not well-established, typically composed of surgery with maximal safe tumor resection. Subsequent chemoradiation is recommended if the patient is older than 3 years. If younger than 3 years, surgery is followed by chemotherapy. In general, “pediatric glioblastomas” also have a poor prognosis despite surgery and adjuvant therapy. Magnetic resonance imaging (MRI) is the imaging modality of choice for the evaluation of glioblastomas. In addition to the typical conventional MRI features, i.e., highly heterogeneous invasive masses with indistinct borders, mass effect on surrounding structures, and a variable degree of enhancement, the lesions may show restricted diffusion in the solid components, hemorrhage, and increased perfusion, reflecting increased vascularity and angiogenesis. In addition, magnetic resonance spectroscopy has proven helpful in pre- and postsurgical evaluation. Lastly, we will refer to new MRI techniques, which have already been applied in evaluating adult glioblastomas, with promising results, yet not widely utilized in children.
Despite advancements in molecular and histopathologic characterization of pediatric low-grade gliomas (pLGGs), there remains significant phenotypic heterogeneity among tumors with similar ...categorizations. We hypothesized that an unsupervised machine learning approach based on radiomic features may reveal distinct pLGG imaging subtypes.
Multi-parametric MR images (T1 pre- and post-contrast, T2, and T2 FLAIR) from 157 patients with pLGGs were collected and 881 quantitative radiomic features were extracted from tumorous region. Clustering was performed using K-means after applying principal component analysis (PCA) for feature dimensionality reduction. Molecular and demographic data was obtained from the PedCBioportal and compared between imaging subtypes.
K-means identified three distinct imaging-based subtypes. Subtypes differed in mutational frequencies of BRAF (p < 0.05) as well as the gene expression of BRAF (p<0.05). It was also found that age (p < 0.05), tumor location (p < 0.01), and tumor histology (p < 0.0001) differed significantly between the imaging subtypes.
In this exploratory work, it was found that clustering of pLGGs based on radiomic features identifies distinct, imaging-based subtypes that correlate with important molecular markers and demographic details. This finding supports the notion that incorporation of radiomic data could augment our ability to better characterize pLGGs.
Objective
Surgical resection of skull base tumors in children is increasingly accomplished through an expanded endonasal approach (EEA). We aim to evaluate the potential effect of the EEA on ...midfacial growth as a result of iatrogenic damage to nasal growth zones.
Methods
We performed a retrospective review of children undergoing craniopharyngioma resection via an open transcranial or EEA. Pre‐ and postoperative magnetic resonance imaging was evaluated for growth in four midfacial measurements based on established cephalometric landmarks: anterior midface height, posterior midface height, palatal length, and sella–nasion distance. Statistical analysis was conducted using a mixed‐effects linear regression model.
Results
Twenty‐two patients underwent an EEA (n = 12) or open transcranial approach (n = 10) for tumor resection with 3 years of imaging follow‐up. There was no difference in midfacial growth between groups for each measurement. Compared to the open group, patients undergoing EEA demonstrated relative anterior midface height growth of −0.42 mm (P = 0.880), posterior midface height growth of −0.44 mm (P = 0.839), palatal length growth of 0.35 mm (P = 0.894), and sella–nasion distance growth of −2.16 (P = 0.365).
Conclusion
We found no difference in midfacial growth measurements between patients undergoing craniopharyngioma resection via an EEA and the open transcranial route after 3 years of imaging follow‐up. Preliminary results on midfacial growth demonstrate that the EEA is a safe alternative to traditional transcranial approaches for the pediatric population. Further investigation with larger sample size and longer duration of follow‐up is warranted to more thoroughly investigate the long‐term implications of the EEA to the skull base.
Level of Evidence
3 Laryngoscope, 130:338–342, 2020
PDF
