ACR Appropriateness Criteria Head Trauma

Standardized reporting for Head CT Scans in patients suspected of traumatic brain injury (TBI): An international expert endeavor

BACKGROUND AND PURPOSE

Traumatic brain injury (TBI) is a major source of health loss and disability worldwide. Accurate and timely diagnosis of TBI is critical for appropriate treatment and management of the condition. Neuroimaging plays a crucial role in the diagnosis and characterization of TBI. Computed tomography (CT) is the first-line diagnostic imaging modality typically utilized in patients with suspected acute mild, moderate and severe TBI. Radiology reports play a crucial role in the diagnostic process, providing critical information about the location and extent of brain injury, as well as factors that could prevent secondary injury. However, the complexity and variability of radiology reports can make it challenging for healthcare providers to extract the necessary information for diagnosis and treatment planning.

METHODS/RESULTS/CONCLUSION

In this article, we report the efforts of an international group of TBI imaging experts to develop a clinical radiology report template for CT scans obtained in patients suspected of TBI and consisting of fourteen different subdivisions (CT technique, mechanism of injury or clinical history, presence of scalp injuries, fractures, potential vascular injuries, potential injuries involving the extra-axial spaces, brain parenchymal injuries, potential injuries involving the cerebrospinal fluid spaces and the ventricular system, mass effect, secondary injuries, prior or coexisting pathology).

Research progress and prospects of benefit-risk assessment methods for umbilical cord mesenchymal stem cell transplantation in the clinical treatment of spinal cord injury

Over the past decade, we have witnessed the development of cell transplantation as a new strategy for repairing spinal cord injury (SCI). However, due to the complexity of the central nervous system (CNS), achieving successful clinical translation remains a significant challenge. Human umbilical cord mesenchymal stem cells (hUMSCs) possess distinct advantages, such as easy collection, lack of ethical concerns, high self-renewal ability, multilineage differentiation potential, and immunomodulatory properties. hUMSCs are promising for regenerating the injured spinal cord to a significant extent. At the same time, for advancing SCI treatment, the appropriate benefit and risk evaluation methods play a pivotal role in determining the clinical applicability of treatment plans. Hence, this study discusses the advantages and risks of hUMSCs in SCI treatment across four dimensions-comprehensive evaluation of motor and sensory function, imaging, electrophysiology, and autonomic nervous system (ANS) function-aiming to improve the rationality of relevant clinical research and the feasibility of clinical translation.

Canadian Association of Radiologists Trauma Diagnostic Imaging Referral Guideline

The Canadian Association of Radiologists (CAR) Trauma Expert Panel consists of adult and pediatric emergency and trauma radiologists, emergency physicians, a family physician, a patient advisor, and an epidemiologist/guideline methodologist. After developing a list of 21 clinical/diagnostic scenarios, a systematic rapid scoping review was undertaken to identify systematically produced referral guidelines that provide recommendations for 1 or more of these clinical/diagnostic scenarios. Recommendations from 49 guidelines and contextualization criteria in the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) for guidelines framework were used to develop 50 recommendation statements across the 21 scenarios related to the evaluation of traumatic injuries. This guideline presents the methods of development and the recommendations for head, face, neck, spine, hip/pelvis, arms, legs, superficial soft tissue injury foreign body, chest, abdomen, and non-accidental trauma.

Post-Traumatic Cerebral Infarction: A Narrative Review of Pathophysiology, Diagnosis, and Treatment

Traumatic brain injury (TBI) is a common diagnosis requiring acute hospitalization. Long-term, TBI is a significant source of health and socioeconomic impact in the United States and globally. The goal of clinicians who manage TBI is to prevent secondary brain injury. In this population, post-traumatic cerebral infarction (PTCI) acutely after TBI is an important but under-recognized complication that is associated with negative functional outcomes. In this comprehensive review, we describe the incidence and pathophysiology of PTCI. We then discuss the diagnostic and treatment approaches for the most common etiologies of isolated PTCI, including brain herniation syndromes, cervical artery dissection, venous thrombosis, and post-traumatic vasospasm. In addition to these mechanisms, hypercoagulability and microcirculatory failure can also exacerbate ischemia. We aim to highlight the importance of this condition and future clinical research needs with the goal of improving patient outcomes after TBI.

Cranial imaging window implantation technique for longitudinal multimodal imaging of the brain environment in live mice

Intravital two-photon microscopy of the mouse brain requires visual access without affecting normal cognitive functions, which is crucial for longitudinal imaging studies that may last several months. In this protocol, we describe the surgical implantation of a metal-free cranial imaging window, which can be used to perform two-photon microscopy and magnetic resonance imaging in the same animal. This multimodal imaging platform enables the investigation of dynamic processes in the central nervous system at a cellular and macroscopic level. For complete details on the use and execution of this protocol in the context of brain cancer, please refer to Zomer et al.¹.

Accuracy of head computed tomography scoring systems in predicting outcomes for patients with moderate to severe traumatic brain injury: A ProTECT III ancillary study

BACKGROUND

Several types of head CT classification systems have been developed to prognosticate and stratify TBI patients.

OBJECTIVE

The purpose of our study was to compare the predictive value and accuracy of the different CT scoring systems, including the Marshall, Rotterdam, Stockholm, Helsinki, and NIRIS systems, to inform specific patient management actions, using the ProTECT III population of patients with moderate to severe acute traumatic brain injury (TBI).

METHODS

We used the data collected in the patients with moderate to severe (GCS score of 4-12) TBI enrolled in the ProTECT III clinical trial. ProTECT III was a NIH-funded, prospective, multicenter, randomized, double-blind, placebo-controlled clinical trial designed to determine the efficacy of early administration of IV progesterone. The CT scoring systems listed above were applied to the baseline CT scans obtained in the trial. We assessed the predictive accuracy of these scoring systems with respect to Glasgow Outcome Scale-Extended at 6 months, disability rating scale score, and mortality.

RESULTS

A total of 882 subjects were enrolled in ProTECT III. Worse scores for each head CT scoring systems were highly correlated with unfavorable outcome, disability outcome, and mortality. The NIRIS classification was more strongly correlated than the Stockholm and Rotterdam CT scores, followed by the Helsinki and Marshall CT classification. The highest correlation was observed between NIRIS and mortality (estimated odds ratios of 4.83).

CONCLUSION

All scores were highly associated with 6-month unfavorable, disability and mortality outcomes. NIRIS was also accurate in predicting TBI patients' management and disposition.

Toward automatic reformation at the orbitomeatal line in head computed tomography using object detection algorithm

Consistent cross-sectional imaging is desirable to accurately detect lesions and facilitate follow-up in head computed tomography (CT). However, manual reformation causes image variations among technologists and requires additional time. We therefore developed a system that reformats head CT images at the orbitomeatal (OM) line and evaluated the system performance using real-world clinical data. Retrospective data were obtained for 681 consecutive patients who underwent non-contrast head CT. The datasets were randomly divided into one of three sets for training, validation, or testing. Four landmarks (bilateral eyes and external auditory canal) were detected with the trained You Look Only Once (YOLO)v5 model, and the head CT images were reformatted at the OM line. The precision, recall, and mean average precision at the intersection over union threshold of 0.5 were computed in the validation sets. The reformation quality in testing sets was evaluated by three radiological technologists on a qualitative 4-point scale. The precision, recall, and mean average precision of the trained YOLOv5 model for all categories were 0.688, 0.949, and 0.827, respectively. In our environment, the mean implementation time was 23.5 ± 2.4 s for each case. The qualitative evaluation in the testing sets showed that post-processed images of automatic reformation had clinically useful quality with scores 3 and 4 in 86.8%, 91.2%, and 94.1% for observers 1, 2, and 3, respectively. Our system demonstrated acceptable quality in reformatting the head CT images at the OM line using an object detection algorithm and was highly time efficient.

Mild-to-Moderate Traumatic Brain Injury: A Review with Focus on the Visual System

Traumatic Brain Injury (TBI) is a major global public health problem. Neurological damage from TBI may be mild, moderate, or severe and occurs both immediately at the time of impact (primary injury) and continues to evolve afterwards (secondary injury). In mild (m)TBI, common symptoms are headaches, dizziness and fatigue. Visual impairment is especially prevalent. Insomnia, attentional deficits and memory problems often occur. Neuroimaging methods for the management of TBI include computed tomography and magnetic resonance imaging. The location and the extent of injuries determine the motor and/or sensory deficits that result. Parietal lobe damage can lead to deficits in sensorimotor function, memory, and attention span. The processing of visual information may be disrupted, with consequences such as poor hand-eye coordination and balance. TBI may cause lesions in the occipital or parietal lobe that leave the TBI patient with incomplete homonymous hemianopia. Overall, TBI can interfere with everyday life by compromising the ability to work, sleep, drive, read, communicate and perform numerous activities previously taken for granted. Treatment and rehabilitation options available to TBI sufferers are inadequate and there is a pressing need for new ways to help these patients to optimize their functioning and maintain productivity and participation in life activities, family and community.

GAN augmentation for multiclass image classification using hemorrhage detection as a case-study

Purpose: In recent years, the development and exploration of deeper and more complex deep learning models has been on the rise. However, the availability of large heterogeneous datasets to support efficient training of deep learning models is lacking. While linear image transformations for augmentation have been used traditionally, the recent development of generative adversarial networks (GANs) could theoretically allow us to generate an infinite amount of data from the real distribution to support deep learning model training. Recently, the Radiological Society of North America (RSNA) curated a multiclass hemorrhage detection challenge dataset that includes over 800,000 images for hemorrhage detection, but all high-performing models were trained using traditional data augmentation techniques. Given a wide variety of selections, the augmentation for image classification often follows a trial-and-error policy. Approach: We designed conditional DCGAN (cDCGAN) and in parallel trained multiple popular GAN models to use as online augmentations and compared them to traditional augmentation methods for the hemorrhage case study. Results: Our experimentations show that the super-minority, epidural hemorrhages with cDCGAN augmentation presented a minimum of 2 × improvement in their performance against the traditionally augmented model using the same classifier configuration. Conclusion: This shows that for complex and imbalanced datasets, traditional data imbalancing solutions may not be sufficient and require more complex and diverse data augmentation methods such as GANs to solve.

Artificial Intelligence with Statistical Confidence Scores for Detection of Acute or Subacute Hemorrhage on Noncontrast CT Head Scans

Purpose

To present a method that automatically detects, subtypes, and locates acute or subacute intracranial hemorrhage (ICH) on noncontrast CT (NCCT) head scans; generates detection confidence scores to identify high-confidence data subsets with higher accuracy; and improves radiology worklist prioritization. Such scores may enable clinicians to better use artificial intelligence (AI) tools.

Materials and Methods

This retrospective study included 46 057 studies from seven "internal" centers for development (training, architecture selection, hyperparameter tuning, and operating-point calibration; n = 25 946) and evaluation (n = 2947) and three "external" centers for calibration (n = 400) and evaluation (n = 16764). Internal centers contributed developmental data, whereas external centers did not. Deep neural networks predicted the presence of ICH and subtypes (intraparenchymal, intraventricular, subarachnoid, subdural, and/or epidural hemorrhage) and segmentations per case. Two ICH confidence scores are discussed: a calibrated classifier entropy score and a Dempster-Shafer score. Evaluation was completed by using receiver operating characteristic curve analysis and report turnaround time (RTAT) modeling on the evaluation set and on confidence score-defined subsets using bootstrapping.

Results

The areas under the receiver operating characteristic curve for ICH were 0.97 (0.97, 0.98) and 0.95 (0.94, 0.95) on internal and external center data, respectively. On 80% of the data stratified by calibrated classifier and Dempster-Shafer scores, the system improved the Youden indexes, increasing them from 0.84 to 0.93 (calibrated classifier) and from 0.84 to 0.92 (Dempster-Shafer) for internal centers and increasing them from 0.78 to 0.88 (calibrated classifier) and from 0.78 to 0.89 (Dempster-Shafer) for external centers (P < .001). Models estimated shorter RTAT for AI-prioritized worklists with confidence measures than for AI-prioritized worklists without confidence measures, shortening RTAT by 27% (calibrated classifier) and 27% (Dempster-Shafer) for internal centers and shortening RTAT by 25% (calibrated classifier) and 27% (Dempster-Shafer) for external centers (P < .001).

Conclusion

AI that provided statistical confidence measures for ICH detection on NCCT scans reliably detected and subtyped hemorrhages, identified high-confidence predictions, and improved worklist prioritization in simulation.Keywords: CT, Head/Neck, Hemorrhage, Convolutional Neural Network (CNN) Supplemental material is available for this article. © RSNA, 2022.

Delayed intracranial hemorrhage of patients with mild traumatic brain injury under antithrombotics on routine repeat CT scan: a systematic review and meta-analysis

In childhood, traumatic brain injury (TBI) poses the unique challenges of an injury to a developing brain and the dynamic pattern of recovery over time, inflicted TBI and its medicolegal ramifications. The mechanisms of injury vary with age, as do the mechanisms that lead to the primary brain injury. As it is common, and is the leading cause of death and disability in the USA and Canada, prevention is the key, and we may need increased legislation to facilitate this. Despite its prevalence, there is an almost urgent need for research to help guide the optimal management and improve outcomes.

Indeed, contrary to common belief, children with severe TBI have a worse outcome and many of the consequences present in teenage years or later. The treatment needs, therefore, to be multifaceted and starts at the scene of the injury and extends into the home and school. In order to do this, the care needs to be multidisciplinary from specialists with a specific interest in TBI and to involve the family, and will often span many decades.

Advanced Neuroimaging Role in Traumatic Brain Injury: A Narrative Review

Traumatic brain injury (TBI) is a common source of morbidity and mortality among civilians and military personnel. Initial routine neuroimaging plays an essential role in rapidly assessing intracranial injury that may require intervention. However, in the context of TBI, limitations of routine neuroimaging include poor visualization of more subtle changes of brain parenchymal after injury, poor prognostic ability and inability to analyze cerebral perfusion, metabolite and mechanical properties. With the development of modern neuroimaging techniques, advanced neuroimaging techniques have greatly boosted the studies in the diagnosis, prognostication, and eventually impacting treatment of TBI. Advances in neuroimaging techniques have shown potential, including (1) Ultrasound (US) based techniques (contrast-enhanced US, intravascular US, and US elastography), (2) Magnetic resonance imaging (MRI) based techniques (diffusion tensor imaging, magnetic resonance spectroscopy, perfusion weighted imaging, magnetic resonance elastography and functional MRI), and (3) molecular imaging based techniques (positron emission tomography and single photon emission computed tomography). Therefore, in this review, we aim to summarize the role of these advanced neuroimaging techniques in the evaluation and management of TBI. This review is the first to combine the role of the US, MRI and molecular imaging based techniques in TBI. Advanced neuroimaging techniques have great potential; still, there is much to improve. With more clinical validation and larger studies, these techniques will be likely applied for routine clinical use from the initial research.

Usage of image registration and three-dimensional visualization tools on serial computed tomography for the analysis of patients with traumatic intraparenchymal hemorrhages

The aim of this study was to apply registration and three-dimensional (3D) display tools to assess the evolution of intraparenchymal hemorrhage (IPH) in patients with traumatic brain injury (TBI). We identified 109 TBI patients who had two computed tomography (CT) scans within 4 days retrospectively. The IPH was manually outlined. The registration was performed in 39 lesions from 29 patients with lesion volume < 1.5 cm on both baseline and follow-up CT. The center of mass (COM) of each lesion was calculated, and the distance between baseline and follow-up CT was used to evaluate the registration effect. The mean distances of COM before registration in the XYZ, XY, and YZ coordinates were 20.5 ± 10.2 mm, 17.8 ± 9.4 mm, and 15.9 ± 9.4 mm, respectively, which decreased significantly (p < 0.001) to 7.9 ± 4.9, 7.8 ± 5.0, and 6.1 ± 4.1 mm after registration. A 3D short video displaying the rendering view of all lesions in 34 randomly selected patients from baseline and follow-up scans were presented side-by-side for comparison. The detection rate of new IPH lesions increased in 3D videos (100%) as compared with axial CT slices (78.6-92.9%). A very high interrater agreement (k = 0.856) on perceiving IPH lesion progression upon viewing 3D video was noted, and the absolute volume increase was significantly higher (p < 0.001) for progressive lesions (median 7.36 cc) over non-progressive lesions (median 0.01 cc). Compared to patients with spontaneous hemorrhagic stroke, evaluation of multiple small traumatic hemorrhages in TBI is more challenging. The applied image analysis and visualization methods may provide helpful tools for comparing changes between serial CT scans.

Contemporary national trends and disparities for head CT use in emergency department settings: Insights from National Hospital Ambulatory Medical Care Survey (NHAMCS) 2007-2017

BACKGROUND

The exponential growth in CT utilization in emergency department (ED) until 2008 raised concerns regarding cost and radiation exposure. Head CT was one of the commonest studies. This led to mitigating efforts such as appropriate use guidelines, policy and payment reforms. The impact of these efforts is not fully understood. In addition, disparities in outcomes of acute conditions presenting to the ED is well known however recent trends in imaging utilization patterns and disparities are not well understood. In this study, we describe nationwide trends and disparities associated with head CT in ED settings between 2007 and 2014.

METHODS

We analyzed 2007-2017 National Hospital Ambulatory Medical Care Survey (NHAMCS) with the primary goal to assess the rate and patterns of head CT imaging in ED.

RESULTS

There were an estimated 117 million in 2007 and 139 million ED visits in 2017. There was a 4% increase in the any CT use in 2017 compared to 2007. No significant change in head CT utilization rate was seen. The 2007 head CT rate was 6.7% (95% CI: 6.1-7.3) compared to 7.7% (95% CI: 6.8-8.6) in 2017. Trauma, Headache and Dizziness are the top three indications for head CT use in the ED respectively. On adjusted analyses, significantly higher head CT utilization was seen in elderly, (age>65 yrs) and significantly lower utilization rate was seen in Non-Hispanic Black and Medicaid patients, and patients in rural locations.

CONCLUSIONS

Previously reported exponential growth of CT use in ED is no longer seen. In particular, there was no significant change in ED head CT use between 2007 and 2017. Headache and Dizziness remain commonly used indications despite limited utility in most clinical scenarios, indicating continued need for appropriate use of imaging. There is significantly lower CT utilization in Non-Hispanic Black, Medicaid patients and those in rural locations, suggesting disparities in diagnostic work-up in marginalized and rural populations. This underscores the need for standardizing care regardless of race, insurance status and location.

Extended Analysis of Axonal Injuries Detected Using Magnetic Resonance Imaging in Critically Ill Traumatic Brain Injury Patients

Studies show conflicting results regarding the prognostic significance of traumatic axonal injuries (TAI) in patients with traumatic brain injury (TBI). Therefore, we documented the presence of TAI in several brain regions, using different magnetic resonance imaging (MRI) sequences, and assessed their association to patient outcomes using machine learning. Further, we created a novel MRI-based TAI grading system with the goal of improving outcome prediction in TBI. We subsequently evaluated the performance of several TAI grading systems. We used a genetic algorithm to identify TAI that distinguish favorable from unfavorable outcomes. We assessed the discriminatory performance (area under the curve [AUC]) and goodness-of-fit (Nagelkerke pseudo-R2) of the novel Stockholm MRI grading system and the TAI grading systems of Adams and associates, Firsching and coworkers. and Abu Hamdeh and colleagues, using both univariate and multi-variate logistic regression. The dichotomized Glasgow Outcome Scale was considered the primary outcome. We examined the MRI scans of 351 critically ill patients with TBI. The TAI in several brain regions, such as the midbrain tegmentum, were strongly associated with unfavorable outcomes. The Stockholm MRI grading system exhibited the highest AUC (0.72 vs. 0.68-0.69) and Nagelkerke pseudo-R2 (0.21 vs. 0.14-0.15) values of all TAI grading systems. These differences in model performance, however, were not statistically significant (DeLong test, p > 0.05). Further, all included TAI grading systems improved outcome prediction relative to established outcome predictors of TBI, such as the Glasgow Coma Scale (likelihood-ratio test, p < 0.001). Our findings suggest that the detection of TAI using MRI is a valuable addition to prognostication in TBI.

Temporal changes in extra-axial brain hematoma's signal intensity in magnetic resonance images of trauma patients: A preliminary, technical study

INTRODUCTION

Dating the exact or estimated time of trauma is an important issue facing forensic medicine. Several clinical and radiological methods were used to achieve this purpose. In the recent study, we aimed to track the changes in the signal intensity of the extra-axial brain hematoma using magnetic resonance imaging (MRI) conventional sequences as well as diffusion-weighted imaging (DWI) and the apparent diffusion coefficient (ADC).

MATERIALS AND METHODS

Considering inclusion and exclusion criteria, all patients with blunt head trauma were involved. After proper management., stabilization, and resuscitation, the participants were assessed using conventional sequences of MRI and DWI twenty-four hours, forty-eight hours, and three weeks after the injury. Temporal changes of signal intensity were compared by Wilcoxon ranged test.

RESULTS

Sixteen patients sustaining blunt head trauma were included in this study. The study showed that during the time, diffusion restriction could be seen in an extraaxial hematoma. At the first 24 hours, the signal of hematoma was void in 87.5% of DWI and 100% of ADC. On the second day, they were hypo-signal in 75% of DWI and 100% 0f ADCs, and after three weeks, 100% of cases were hyper-signal in DWI and hypo-signal ADCs.

CONCLUSION

This preliminary study has shown that the DWI can be used to detect and track the extra-axial hematoma. The signal intensity was void during the first twentyfour hours, although it became hypo-signal after 48 hours. Of note, the diffusion restriction is noted after three weeks.

Convolutional neural network performance compared to radiologists in detecting intracranial hemorrhage from brain computed tomography: A systematic review and meta-analysis

PURPOSE

To compare the diagnostic accuracy of convolutional neural networks (CNN) with radiologists as the reference standard in the diagnosis of intracranial hemorrhages (ICH) with non contrast computed tomography of the cerebrum (NCTC).

METHODS

PubMed, Embase, Scopus, and Web of Science were searched for the period from 1 January 2012 to 20 July 2020; eligible studies included patients with and without ICH as the target condition undergoing NCTC, studies had deep learning algorithms based on CNNs and radiologists reports as the minimum reference standard. Pooled sensitivities, specificities and a summary receiver operating characteristics curve (SROC) were employed for meta-analysis.

RESULTS

5,119 records were identified through database searching. Title-screening left 47 studies for full-text assessment and 6 studies for meta-analysis. Comparing the CNN performance to reference standards in the retrospective studies found a pooled sensitivity of 96.00% (95% CI: 93.00% to 97.00%), pooled specificity of 97.00% (95% CI: 90.00% to 99.00%) and SROC of 98.00% (95% CI: 97.00% to 99.00%), and combining retrospective and studies with external datasets found a pooled sensitivity of 95.00% (95% CI: 91.00% to 97.00%), pooled specificity of 96.00% (95% CI: 91.00% to 98.00%) and a pooled SROC of 98.00% (95% CI: 97.00% to 99.00%).

CONCLUSION

This review found the diagnostic performance of CNNs to be equivalent to that of radiologists for retrospective studies. Out-of-sample external validation studies pooled with retrospective studies found CNN performance to be slightly worse. There is a critical need for studies with a robust reference standard and external data-set validation.

Predicting factors for abnormal brain computed tomography in children with minor head trauma

Background

Deciding whether a cranial Computed Tomography (CT) scan in a patient with minor head trauma (MHT) is necessary or not has always been challenging. Diagnosing Traumatic Brain Injury (TBI) is a fundamental part of MHT managing especially in children who are more vulnerable in terms of brain CT radiation consequences and TBI. Defining some indications to timely and efficiently predict the likelihood of TBI is necessary. Thus, we aimed to determine the impact of clinical findings to predict the need for brain CT in children with MHT.

Methods

In a prospective cohort study, 200 children (2 to 14 years) with MHT were included from 2019 to 2020. The data of MHT-related clinical findings were gathered. The primary and secondary outcomes were defined as a positive brain CT and any TBI requiring neurosurgery intervention, respectively. In statistical analysis, we performed Binary Logistic regression analysis, Fisher’s exact test and independent samples t-test using SPSS V.26.

Results

The mean age of participants was 6.5 ± 3.06 years. Ninety patients underwent brain CT. The most common clinical finding and injury mechanism were headache and falling from height, respectively. The results of brain CTs were positive in seven patients (3.5%). We identified three predicting factors for an abnormal brain CT including headache, decreased level of consciousness, and vomiting.

Conclusion

We showed that repetitive vomiting (≥2), headache, and decreased level of consciousness are predicting factors for an abnormal brain CT in children with MHT.

Evaluation of ultrashort echo-time (UTE) and fast-field-echo (FRACTURE) sequences for skull bone visualization and fracture detection - A postmortem study

BACKGROUND AND PURPOSE

CT is considered the modality of choice in the assessment of the skull due to the fast and accurate depiction of bone structures. Nevertheless, MRI has evolved into a possible alternative due to optimal soft tissue contrast and recent advances with the ability to visualize tissues with shortest T2 times, such as osseous structures. In this study we compare skull bone visualization and fracture detection across two MRI sequences to CT as reference standard.

MATERIAL AND METHODS

Twenty subjects underwent CT and MRI with less than 72 h between examination. The MRI protocol included a 2D ultrashort echo time (UTE) and a 3D multi-echo in-phase fast-field-echo (FRACTURE) sequence. Independent raters evaluated qualitative characteristics and fracture detectability in different skull subregions (skull vault, skull base and viscerocranium). Interrater and intermodality agreement was evaluated by calculating intraclass coefficients (ICC).

RESULTS

FRACTURE ICC indicated a good agreement in all subregions (ICC = 0.83 - 0.88), whereas UTE had excellent results calculated in the skull vault and viscerocranium (ICC = 0.91 - 0.94). At the skull vault, both MRI sequences received an overall good rating (UTE: 2.63 ± 0.42 FRACTURE. 2.81 ± 0.32). Fracture detection using MRI sequences for the skull vault, was highest compared to other subregions.

CONCLUSIONS

Both MRI sequences may provide an alternative e.g. for surgical planning or follow up exams of the osseous neurocranium; although, at the skull base and viscerocranium bone visualization with MRI bone imaging sequences perform inferior to CT standard imaging.

Variation in radiation dosing among pediatric trauma patients undergoing head computed tomography scan

BACKGROUND

When head injured children undergo head computed tomography (CT), radiation dosing can vary considerably between institutions, potentially exposing children to excess radiation, increasing risk for malignancies later in life. We compared radiation delivery from head CTs at a level 1 pediatric trauma center (PTC) versus scans performed at referring adult general hospitals (AGHs). We hypothesized that children at our PTC receive a significantly lower radiation dose than children who underwent CT at AGHs for similar injury profiles.

METHODS

We retrospectively reviewed the charts of all patients younger than 18 years who underwent CT for head injury at our PTC or at an AGH before transfer between January 1 and December 31, 2019. We analyzed demographic and clinical data. Our primary outcome was head CT radiation dose, as calculated by volumetric CT dose index (CTDIvol) and dose-length product (DLP; the product of CTDIvol and scan length). We used unadjusted bivariate and multivariable linear regression (adjusting for age, weight, sex) to compare doses between Children's Hospital Los Angeles and AGHs.

RESULTS

Of 429 scans reviewed, 193 were performed at our PTC, while 236 were performed at AGHs. Mean radiation dose administered was significantly lower at our PTC compared with AGHs (CTDIvol 20.3/DLP 408.7 vs. CTDIvol 30.6/DLP 533, p < 0.0001). This was true whether the AGH was a trauma center or not. After adjusting for covariates, findings were similar for both CTDIvol and DLP. Patients who underwent initial CT at an AGH and then underwent a second CT at our PTC received less radiation for the second CT (CTDIvol 25.6 vs. 36.5, p < 0.0001).

CONCLUSIONS

Head-injured children consistently receive a lower radiation dose when undergoing initial head CT at a PTC compared with AGHs. This provides a basis for programs aimed at establishing protocols to deliver only as much radiation as necessary to children undergoing head CT.

LEVEL OF EVIDENCE

Care Management/Therapeutic, level IV.

Improved neuropathological identification of traumatic brain injury through quantitative neuroimaging and neural network analyses: Some practical approaches for the neurorehabilitation clinician

BACKGROUND

Quantitative neuroimaging analyses have the potential to provide additional information about the neuropathology of traumatic brain injury (TBI) that more thoroughly informs the neurorehabilitation clinician.

OBJECTIVE

Quantitative neuroimaging is typically not covered in the standard radiological report, but often can be extracted via post-processing of clinical neuroimaging studies, provided that the proper volume acquisition sequences were originally obtained.

METHODS

Research and commercially available quantitative neuroimaging methods provide region of interest (ROI) quantification metrics, lesion burden volumetrics and cortical thickness measures, degree of focal encephalomalacia, white matter (WM) abnormalities and residual hemorrhagic pathology. If present, diffusion tensor imaging (DTI) provides a variety of techniques that aid in evaluating WM integrity. Using quantitatively identified structural and ROI neuropathological changes are most informative when done from a neural network approach.

RESULTS

Viewing quantitatively identifiable damage from a neural network perspective provides the neurorehabilitation clinician with an additional tool for linking brain pathology to understand symptoms, problems and deficits as well as aid neuropsychological test interpretation. All of these analyses can be displayed in graphic form, including3-D image analysis. A case study approach is used to demonstrate the utility of quantitative neuroimaging and network analyses in TBI.

CONCLUSIONS

Quantitative neuroimaging may provide additional useful information for the neurorehabilitation clinician.

Exploring the potential of cranial non-metric traits as a tool for personal identification: the never-ending dilemma

Forensic anthropologists tasked with identification of skeletal remains often have to set up new strategies to overcome the limitations of conventional individualizing markers. A sound acquaintance with non-metric traits is essential for a reliable distinction between normal variations and pathological or traumatic conditions, yet the role of cranial variants in the identification process is still somehow ill-defined. One hundred crania (50 males and 50 females) of known sex and age were selected from the Collezione Antropologica LABANOF (a documented contemporary skeletal collection) and non-metric traits were scored as present or absent and by side. The frequencies of 13 traits were used to calculate the compound probabilities to find an individual with an exact combination of cranial features in the worldwide population. The probabilities of the majority of the individuals (53%) are within the 1 out of 10 million-1 out of 1 million interval. However, a fair number of subjects (25%) of the sample have the probabilities falling into the 1 out of 1 billion-1 out of 100 million interval, while the probabilities of a small portion of the sample (10%) are less than 1 out of 1 billion. This pilot study illustrates that some combinations of cranial variants are quite rare and may represent potential evidence to discern presumptive identifications, when an appropriate set of traits is selected and antemortem data are available for comparison. However, further research on larger and various samples is needed to confirm or discard the use of combinations of cranial non-metric traits as individualizing markers.

Impact of implementation of the national institute for health and clinical excellence (NICE) head injury guideline in a tertiary care center emergency department: A pre and post-intervention study

INTRODUCTION

Head injury, a common presentation to the emergency department (ED), is a substantial problem in developing countries like Nepal. The current national institute for health and clinical excellence (NICE) guideline revised in January 2014 focuses on effective clinical assessment and early management of head injuries according to their severity in all age groups. This study assessed the impact of implementing this guideline on the proportions of computed tomography (CT) head scans, guideline adherence, and confidence level of the attending physicians.

METHODS

We consecutively recruited 139 traumatic head injury (THI) patients in this prospective pre-post interventional study conducted in the ED of a tertiary care center. We implemented the NICE guideline into routine practice using multimodal intervention through physicians' education sessions, information sheets and guideline-dissemination. The pre and post-implementation CT head scan rates were compared. The post-implementation guideline adherence was assessed. Online Google form-questionnaires including 12 validated case scenarios were distributed to the attending physicians at the end of both phases to assess their confidence levels.

RESULTS

The implementation resulted in a statistically significant decrease in the proportion of CT head scan rates from 92.0% to 70.0% (p-value = 0.005). Following educational interventions, improved guideline adherence of 20.3 percentage points (p-value = 0.001) was observed. Nine ED attending physicians were enrolled in the study who showed statistically significant improvement in their confidence level following the intervention. The NICE guideline showed a sensitivity and specificity of 93.6% and 76.4% with 82.6% accuracy compared to that of clinical judgment (100%, 34.6%, and 58.1% respectively) in detecting intracranial lesions.

CONCLUSION

The implementation was successful in satisfying the aim of the NICE guideline by decreasing the proportion of CT head scans, improving guideline adherence and increasing the confidence of the attending physicians.

A Delphi study to identify prehospital and emergency department trauma care modifiers for older adults

Background

Older patients (age ≥ 65 yr) with trauma have increased morbidity and mortality compared to younger patients; this is partly explained by undertriage of older patients with trauma, resulting in lack of transfer to a trauma centre or failure to activate the trauma team. The objective of this study was to identify modifiers to the prehospital and emergency department phases of major trauma care for older adults based on expert consensus.

Methods

We conducted a modified Delphi study between May and September 2019 to identify major trauma care modifiers for older adults based on national expert consensus. The panel consisted of 24 trauma care professionals from across Canada from the prehospital and emergency department phases of care. The survey consisted of 16 trauma care modifiers. Three online survey rounds were distributed. Consensus was defined a priori as a disagreement index score less than 1.

Results

There was a 100% response rate for all survey rounds. Three new trauma care modifiers were suggested by panellists. The panel achieved consensus agreement for 17 of the 19 trauma care modifiers. The prehospital modifier with the strongest agreement to transfer to a trauma centre was a respiratory rate less than 10 or greater than 20 breaths/min or need for ventilatory support. The emergency department modifier with the strongest level of agreement was obtaining 12-lead electrocardiography following the primary and secondary survey.

Conclusion

Using a modified Delphi process, an expert panel agreed on 17 trauma care modifiers for older adults in the prehospital and emergency department settings. These modifiers may improve the delivery of trauma care for older adults and should be considered when developing local and national trauma guidelines.

Does the choice of the reference model affect the results of 3D-3D superimposition procedure? A comparison of different protocols for personal identification

In literature, 3D-3D superimposition has been widely recognized as a valid method for personal identification. However, very little information is available about possible variability due to differences in protocols of registration of 3D models and calculation of RMS (root mean square) point-to-point distance. Frontal sinuses from 50 CT scans were segmented twice through the ITK-SNAP software and grouped in two samples (1 and 2). Maximum breadth, height and volume were measured. 3D models belonging to the same subject were then superimposed one on each other in 50 matches. In addition, superimposition of 50 random mismatches was performed. For each superimposition, the procedure was repeated four times choosing different reference models both for registration and calculation of RMS. Differences in RMS value among protocols of registration and RMS calculation were assessed through paired Student's t-test (p < 0.05). Possible correlations between differences in RMS among groups and differences in frontal sinus size between the superimposed models were analysed through calculation of Pearson's correlation coefficient (p < 0.05). Results showed that RMS calculation did not yield significant differences according to which 3D model is used as reference; on the other hand, RMS values from registration procedure significantly differ according to which model is chosen as reference, but only in the mismatch group (p < 0.001). Differences in RMS value according to RMS calculation are dependent upon all the three measurements, whereas differences according to registration protocols were significantly related only with the breadth of frontal sinuses but only in mismatches (p < 0.001). In no case, superimpositions of RMS values were found between matches and mismatches. This article for the first time proves that the protocol of registration and calculation of RMS significantly influences the results of 3D-3D superimposition only in case of mismatches.

Emerging Utility of Applied Magnetic Resonance Imaging in the Management of Traumatic Brain Injury

Traumatic brain injury (TBI) is a widespread and expensive problem globally. The standard diagnostic workup for new TBI includes obtaining a noncontrast computed tomography image of the head, which provides quick information on operative pathologies. However, given the limited sensitivity of computed tomography for identifying subtle but meaningful changes in the brain, magnetic resonance imaging (MRI) has shown better utility for ongoing management and prognostication after TBI. In recent years, advanced applications of MRI have been further studied and are being implemented as clinical tools to help guide care. These include functional MRI, diffusion tensor imaging, MR perfusion, and MR spectroscopy. In this review, we discuss the scientific basis of each of the above techniques, the literature supporting their use in TBI, and how they may be clinically implemented to improve the care of TBI patients.

MRI Volumetric Quantification in Persons with a History of Traumatic Brain Injury and Cognitive Impairment

BACKGROUND

While traumatic brain injury (TBI) is recognized as a risk factor for dementia, there is lack of clinical tools to identify brain changes that may confer such vulnerability. Brain MRI volumetric quantification can sensitively identify brain atrophy.

OBJECTIVE

To characterize regional brain volume loss in persons with TBI presenting with cognitive impairment.

METHODS

IRB approved review of medical records in patients with cognitive decline focused on those who had documented TBI histories and brain MRI scans after TBI (n = 40, 67.7±14.5 years) with volumetric quantification by applying an FDA cleared software program. TBI documentation included head trauma mechanism. Brain volumes were compared to a normative database to determine the extent of atrophy. Correlations between these regions and global tests of cognition (MMSE in n = 17, MoCA in n = 27, n = 14 in both) were performed.

RESULTS

Multiple regions demonstrated volume loss in TBI, particularly ventral diencephalon, putamen, and pallidum with smaller magnitude of atrophy in temporal lobes and brainstem. Lobar structures showed strongest correlations between atrophy and lower scores on MMSE and MoCA. The hippocampus, while correlated to tests of cognitive function, was the least atrophic region as a function of TBI history.

CONCLUSION

Persons with TBI history exhibit show regional brain atrophy. Several of these areas, such as thalamus and temporal lobes, also correlate with cognitive function. Alzheimer's disease atrophy was less likely given relative sparing of the hippocampi. Volumetric quantification of brain MRI in TBI warrants further investigation to further determine its clinical potential in TBI and differentiating causes of cognitive impairment.

ACR Appropriateness Criteria® Headache

Headache is one of the most common human afflictions. In most cases, headaches are benign and idiopathic, and resolve spontaneously or with minor therapeutic measures. Imaging is not required for many types of headaches. However, patients presenting with headaches in the setting of "red flags" such as head trauma, cancer, immunocompromised state, pregnancy, patients 50 years or older, related to activity or position, or with a corresponding neurological deficit, may benefit from CT, MRI, or noninvasive vascular imaging to identify a treatable cause. This publication addresses the initial imaging strategies for headaches associated with the following features: severe and sudden onset, optic disc edema, "red flags," migraine or tension-type, trigeminal autonomic origin, and chronic headaches with and without new or progressive features. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Computed Tomographic Imaging Appraisal of Traumatic Brain Injury in a Tertiary Hospital in South-South Nigeria: A 6-Year Review

Background:

Computed tomography (CT) remains the gold standard in imaging evaluations of traumatic brain injury (TBI). TBI on its own has become a major concern in developing countries with its untoward effects.

Objectives:

The objective was to appraise the craniocerebral computed tomograms of patients who had TBIs.

Materials and Methods:

A retrospective study of patients who underwent craniocerebral CT on account of head injury in the University of Uyo Teaching Hospital, Uyo, Nigeria, from November 13, 2013 to May 31, 2019 was done. The duration was regardless of the disjointed periods of service interruption. Patients' demographic and CT features were evaluated with application of simple analysis of data.

Results:

Two hundred and thirty-two patients were evaluated with minimum and maximum ages of 6 months and 78 years, respectively. Males were predominant with a ratio of 2.74: 1. Most affected age ranges were 30–39 years (23.27%) and 20–29 (22.84%). Normal brain CT was seen in 44 patients (18.97%). The most frequent lesion in patients with abnormal CT was intracranial hemorrhages (n = 188, 81.03%). Here, extra-axial hemorrhages (n = 100, 53.19%) supersede intracerebral hemorrhages (n = 88, 46.81%). Half of the intracerebral hemorrhages were multiple. Calvarial fractures were seen in 34.48% (n = 80) of patients. The most common localization was the facial bones (n = 24, 30.00%), whereas the least site was the occipital bone (n = 4, 5.00%). Fifteen percent of the patients had multiple fractures which also included base of the skull.

Conclusion:

TBIs commonly occur among young active males. The most frequent lesion is intracranial hemorrhages with extra-axial bias.

ACR Appropriateness Criteria® Acute Mental Status Change, Delirium, and New Onset Psychosis

Acute changes in mental status represent a broad collection of symptoms used to describe disorders in mentation and level of arousal, including the more narrowly defined diagnoses of delirium and psychosis. A wide range of precipitating factors may be responsible for symptom onset including infection, intoxication, and metabolic disorders. Neurologic causes that may be detected on neuroimaging include stroke, traumatic brain injury, nonconvulsive seizure, central nervous system infection, tumors, hydrocephalus, and inflammatory disorders. Not infrequently, two or more precipitating factors may be found. Neuroimaging with CT or MRI is usually appropriate if the clinical suspicion for an acute neurological cause is high, where the cause of symptoms is not found on initial assessment, and for patients whose symptoms do not respond appropriately to management. There was disagreement regarding the appropriateness of neuroimaging in cases where a suspected, nonneurologic cause is found on initial assessment. Neuroimaging with CT is usually appropriate for patients presenting with delirium, although the yield may be low in the absence of trauma or a focal neurological deficit. Neuroimaging with CT or MRI may be appropriate in the evaluation of new onset psychosis, although the yield may be low in the absence of a neurologic deficit. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Conditional unnecessity of head CT for whole-body CT of traffic accident victims: a pilot study

PURPOSE

To investigate whether head CT should be included in whole-body CT in road traffic accident victims.

METHODS

A review of electronic medical records identified 124 patients (81 males, 43 females; age 4 to 92 years, mean 47.7 years) involved in a road traffic accident in a 12-month period. All had undergone whole-body CT and physical and neurologic examinations. We recorded their age, sex, Glasgow Coma Scale (GCS), systolic blood pressure (SBP), the type of traffic accident, and the presence/absence of visible trauma above the clavicles (VTCs) and of acute traumatic brain injury (TBI) on CT. Statistical analyses were performed to evaluate predictors of acute TBI.

RESULTS

Of 124 patients, 34 (27%) manifested acute TBI on CT. Univariate analysis identified their age, GCS, SBP, VTCs, and the accident type as statistically significant factors for acute TBI (p < 0.05). Multivariate analysis demonstrated VTCs, GCS score < 15, and SBP ≤ 90 mmHg were significant independent predictors of acute TBI (p = 0.001, p = 0.001, and p = 0.004, respectively); the odds ratio was 16.07 for VTCs, 14.85 for GCS score < 15, and 13.78 for SBP ≤ 90 mmHg. No patients without both decrease in GCS score and VTCs manifested acute TBI.

CONCLUSION

Our pilot study showed that visible trauma above the clavicles and decrease in GCS score were highly associated with the presence of acute TBI in road traffic accident victims. In whole-body CT, a head CT may not be indicated in patients without these factors.

Emergency department management of traumatic brain injuries: A resource tiered review

Introduction

Traumatic brain injury is a leading cause of death and disability globally with an estimated African incidence of approximately 8 million cases annually. A person suffering from a TBI is often aged 20–30, contributing to sustained disability and large negative economic impacts of TBI. Effective emergency care has the potential to decrease morbidity from this multisystem trauma.

Objectives

Identify and summarize key recommendations for emergency care of patients with traumatic brain injuries using a resource tiered framework.

Methods

A literature review was conducted on clinical care of brain-injured patients in resource-limited settings, with a focus on the first 48 h of injury. Using the AfJEM resource tiered review and PRISMA guidelines, articles were identified and used to describe best practice care and management of the brain-injured patient in resource-limited settings.

Key recommendations

Optimal management of the brain-injured patient begins with early and appropriate triage. A complete history and physical can identify high-risk patients who present with mild or moderate TBI. Clinical decision rules can aid in the identification of low-risk patients who require no neuroimaging or only a brief period of observation. The management of the severely brain-injured patient requires a systematic approach focused on the avoidance of secondary injury, including hypotension, hypoxia, and hypoglycaemia. Most interventions to prevent secondary injury can be implemented at all facility levels. Urgent neuroimaging is recommended for patients with severe TBI followed by consultation with a neurosurgeon and transfer to an intensive care unit. The high incidence and poor outcomes of traumatic brain injury in Africa make this subject an important focus for future research and intervention to further guide optimal clinical care.

Vascular Trauma in the Head and Neck and Endovascular Neurointerventional Management

Traumatic vascular injuries of the head and neck can pose life-threatening emergencies, and therefore, the detection and accurate characterization of these injuries by the radiologist is essential. Computed tomographic angiography (CTA) is commonly performed as part of the initial imaging work-up of patients who have sustained blunt or penetrating craniocervical injuries and are suspected to have or are at risk for vascular injuries. This pictorial essay reviews the CTA and conventional angiographic imaging appearance of various vascular injuries that can occur from trauma in the head and neck and also explores the neurointerventional management of these types of injuries.

Traumatic Brain Injury: Imaging Patterns and Complications

While the diagnosis of traumatic brain injury (TBI) is a clinical decision, neuroimaging remains vital for guiding management on the basis of identification of intracranial pathologic conditions. CT is the mainstay of imaging of acute TBI for both initial triage and follow-up, as it is fast and accurate in detecting both primary and secondary injuries that require neurosurgical intervention. MRI is more sensitive for the detection of certain intracranial injuries (eg, axonal injuries) and blood products 24-48 hours after injury, but it has limitations (eg, speed, accessibility, sensitivity to motion, and cost). The evidence primarily supports the use of MRI when CT findings are normal and there are persistent unexplained neurologic findings or at subacute and chronic periods. Radiologists should understand the role and optimal imaging modality to use, in addition to patterns of primary brain injury and their influence on the risk of developing secondary brain injuries related to herniation. ^©RSNA, 2019 See discussion on this article by Mathur and Nicolaou.

CT Scanning in Suspected Stroke or Head Trauma: Is it Worth Going the Extra Mile and Including the Chest to Screen for COVID-19 Infection?

BACKGROUND AND PURPOSE

Chest CT may be used as a tool for rapid coronavirus disease 2019 (COVID-19) detection. Our aim was to investigate the value of additional chest CT for detection of coronavirus 19 (COVID-19) in patients who undergo head CT for suspected stroke or head trauma in a COVID-19-endemic region.

MATERIALS AND METHODS

Our study included 27 patients (mean age, 74 years; range, 54-90 years; 20 men) who underwent head CT for suspected stroke (n = 21) or head trauma (n = 6), additional chest CT for COVID-19 detection, and real-time reverse transcriptase polymerase chain reaction testing in a COVID-19-endemic region. Sensitivity, specificity, and negative and positive predictive values of chest CT in detecting COVID-19 were calculated.

RESULTS

Final neurologic diagnoses were ischemic stroke (n = 11), brain contusion (n = 5), nontraumatic intracranial hemorrhage (n = 2), brain metastasis (n = 1), and no primary neurologic disorder (n = 8). Symptoms of possible COVID-19 infection (ie, fever, cough, and/or shortness of breath) were present in 20 of 27 (74%) patients. Seven of 27 patients (26%) had real-time reverse transcriptase polymerase chain reaction confirmed-COVID-19 infection. Chest CT results were 6 true-positives, 15 true-negatives, 5 false-positives, and 1 false-negative. Diagnostic performance values of chest CT were a sensitivity of 85.7%, specificity of 75.0%, negative predictive value of 93.8%, and positive predictive value of 54.6%.

CONCLUSIONS

The sensitivity of additional chest CT is fairly high. However, a negative result does not exclude COVID-19. The positive predictive value is poor. Correlation of chest CT results with epidemiologic history and clinical presentation, along with real-time reverse transcriptase polymerase chain reaction, is needed for confirmation.

Mechanisms of Blood-Brain Barrier Dysfunction in Traumatic Brain Injury

Traumatic brain injuries (TBIs) account for the majority of injury-related deaths in the United States with roughly two million TBIs occurring annually. Due to the spectrum of severity and heterogeneity in TBIs, investigation into the secondary injury is necessary in order to formulate an effective treatment. A mechanical consequence of trauma involves dysregulation of the blood–brain barrier (BBB) which contributes to secondary injury and exposure of peripheral components to the brain parenchyma. Recent studies have shed light on the mechanisms of BBB breakdown in TBI including novel intracellular signaling and cell–cell interactions within the BBB niche. The current review provides an overview of the BBB, novel detection methods for disruption, and the cellular and molecular mechanisms implicated in regulating its stability following TBI.

Structural and Volumetric Brain MRI Findings in Mild Traumatic Brain Injury

BACKGROUND AND PURPOSE

Routine MR imaging findings are frequently normal following mild traumatic brain injury and have a limited role in diagnosis and management. Advanced MR imaging can assist in detecting pathology and prognostication but is not readily available outside research settings. However, 3D isotropic sequences with ∼1-mm³ voxel size are available on community MR imaging scanners. Using such sequences, we compared radiologists' findings and quantified regional brain volumes between a mild traumatic brain injury cohort and non-brain-injured controls to describe structural imaging findings associated with mild traumatic brain injury.

MATERIALS AND METHODS

Seventy-one military personnel with persistent symptoms and 75 controls underwent 3T MR imaging. Three neuroradiologists interpreted the scans using common data elements. FreeSurfer was used to quantify regional gray and white matter volumes.

RESULTS

WM hyperintensities were seen in 81% of the brain-injured group versus 60% of healthy controls. The odds of ≥1 WM hyperintensity in the brain-injured group was about 3.5 times the odds for healthy controls (95% CI, 1.58-7.72; P = .002) after adjustment for age. A frontal lobe-only distribution of WM hyperintensities was more commonly seen in the mild traumatic brain injury cohort. Furthermore, 7 gray matter, 1 white matter, and 2 subcortical gray matter regions demonstrated decreased volumes in the brain-injured group after multiple-comparison correction. The mild traumatic brain injury cohort showed regional parenchymal volume loss.

CONCLUSIONS

White matter findings are nonspecific and therefore a clinical challenge. Our results suggest that prior trauma should be considered in the differential diagnosis of multifocal white matter abnormalities with a clinical history of mild traumatic brain injury, particularly when a frontal predilection is observed.

Advanced neuroimaging in traumatic brain injury: an overview

Traumatic brain injury (TBI) is a common condition with many potential acute and chronic neurological consequences. Standard initial radiographic evaluation includes noncontrast head CT scanning to rapidly evaluate for pathology that might require intervention. The availability of fast, relatively inexpensive CT imaging has fundamentally changed the clinician's ability to noninvasively visualize neuroanatomy. However, in the context of TBI, limitations of head CT without contrast include poor prognostic ability, inability to analyze cerebral perfusion status, and poor visualization of underlying posttraumatic changes to brain parenchyma. Here, the authors review emerging advanced imaging for evaluation of both acute and chronic TBI and include QuickBrain MRI as an initial imaging modality. Dynamic susceptibility-weighted contrast-enhanced perfusion MRI, MR arterial spin labeling, and perfusion CT are reviewed as methods for examining cerebral blood flow following TBI. The authors evaluate MR-based diffusion tensor imaging and functional MRI for prognostication of recovery post-TBI. Finally, MR elastography, MR spectroscopy, and convolutional neural networks are examined as future tools in TBI management. Many imaging technologies are being developed and studied in TBI, and some of these may hold promise in improving the understanding and management of TBI. ABBREVIATIONS ASL = arterial spin labeling; CNN = convolutional neural network; CTP = perfusion CT; DAI = diffuse axonal injury; DMN = default mode network; DOC = disorders of consciousness; DTI = diffusion tensor imaging; FA = fractional anisotropy; fMRI = functional MRI; GCS = Glasgow Coma Scale; MD = mean diffusivity; MRE = MR elastography; MRS = MR spectroscopy; mTBI = mild TBI; NAA = N-acetylaspartate; SWI = susceptibility-weighted imaging; TBI = traumatic brain injury; UHF = ultra-high field.

Concussion in Combination With Whiplash-Associated Disorder May Be Missed in Primary Care: Key Recommendations for Assessment and Management

Whiplash and concussion may have similar presenting symptoms, biomechanical mechanisms, and neurophysiological sequelae, but neither enjoys a gold standard diagnostic test. Guidelines for whiplash and concussion are developed and implemented separately. This disparate process may contribute to misdiagnosis, delay appropriate primary care management, and impair patient outcomes. In our clinical commentary, we present 3 cases where signs and symptoms consistent with whiplash were identified in primary care. Symptoms in all cases included neck pain, headache, dizziness, and concentration deficits, raising suspicion of coexisting postconcussion syndrome. All cases were referred for specialist physical therapy. Characteristics consistent with poor recovery in both whiplash and postconcussion syndrome were confirmed, and multidisciplinary management, drawing from both whiplash and concussion guidelines, was implemented. All patients reported improvement in activities of daily living after tailored management addressing both neck and head injury-related factors, suggesting that these conditions were not mutually exclusive. Self-reported outcomes included reductions in neck disability and postconcussion symptoms of between 20% and 40%. It may be appropriate for whiplash and concussion guidelines to be amalgamated, enhanced, and mutually recognized on a patient-by-patient basis. Primary health care professionals might consider minimum screening to identify postconcussion syndrome in patients following motor vehicle collision by administering questionnaires and assessing cranial nerve function, balance, and cognition. Management should then incorporate principles from both whiplash and concussion guidelines and harmonize with available imaging guidelines for suspected spine and head trauma. J Orthop Sports Phys Ther 2019;49(11):819-828. doi:10.2519/jospt.2019.8946.

Three-dimensional analysis of sphenoid sinus uniqueness for assessing personal identification: a novel method based on 3D-3D superimposition

Sphenoid sinuses are considered the most variable structures of human body: therefore, they may be used for personal identification, through the application of 3D segmentation procedures. This study aims at proposing a new protocol for personal identification based on 3D-3D superimposition of sphenoid sinuses segmented from head CT scans. Adult subjects (equally divided among males and females) who underwent two head CT scans were extracted from a hospital database. Sphenoid sinuses were segmented through ITK-SNAP software and the corresponding 3D models were automatically superimposed to obtain 40 matches (when they belonged to the same person) and 260 mismatches (when they were extracted from different individuals). The RMS (root mean square) point-to-point distance was then calculated for all the superimpositions: differences according to sex and group (matches and mismatches) were assessed through the Mann-Whitney test (p < 0.05). On average, the RMS value was almost ten times smaller in matches (0.22 ± 0.11 mm) than in mismatches (2.16 ± 0.57 mm) with a statistically significant difference according to group (p < 0.05), but not to sex (p > 0.05). The study proposed a new method for assessing personal identification from segmented 3D models of sphenoid sinuses, useful in the forensic contexts where other methods might not be implementable or successful.

Neuroimaging of Traumatic Brain Injury

The purpose of this article is to review conventional and advanced neuroimaging techniques performed in the setting of traumatic brain injury (TBI). The primary goal for the treatment of patients with suspected TBI is to prevent secondary injury. In the setting of a moderate to severe TBI, the most appropriate initial neuroimaging examination is a noncontrast head computed tomography (CT), which can reveal life-threatening injuries and direct emergent neurosurgical intervention. We will focus much of the article on advanced neuroimaging techniques including perfusion imaging and diffusion tensor imaging and discuss their potentials and challenges. We believe that advanced neuroimaging techniques may improve the accuracy of diagnosis of TBI and improve management of TBI.

Near-Term Decrease in Brain Volume following Mild Traumatic Injury Is Detectible in the Context of Preinjury Volumetric Stability: Neurobiologic Insights from Analysis of Historical Imaging Examinations

BACKGROUND AND PURPOSE

Neurodegeneration after mild traumatic brain injury may manifest as decreasing regional brain volume that evolves from months to years following mild traumatic brain injury and is associated with worse clinical outcomes. We hypothesized that quantitative brain volume derived from CT of the head, performed for clinical indications during routine care, would change with time and provide insights into the putative neuroinflammatory response to mild traumatic brain injury.

MATERIALS AND METHODS

We searched the electronic medical record of our institution for NCCTs of the head performed in patients with mild traumatic brain injury and included those who also underwent NCCTs of the head 1 month to 1 year before and after mild traumatic brain injury for an indication unrelated to trauma. Controls underwent 3 sequential NCCTs of the head with indications unrelated to trauma. The whole-brain and intracranial volume groups were computed using ITK-SNAP. Brain volumes normalized to intracranial volumes were compared across time points using the Wilcoxon signed-rank test.

RESULTS

We identified 48 patients from 2005 to 2015 who underwent NCCTs of the head in the emergency department for mild traumatic brain injury and had NCCTs of the head performed both before and after mild traumatic brain injury. Median normalized brain volumes significantly decreased on the follow-up study post-mild traumatic brain injury (0.86 versus 0.84, P < .001) and were similar compared with pre-mild traumatic brain injury studies (0.87 versus 0.86, P = .927). There was no significant difference between normalized brain volumes in the 48 controls.

CONCLUSIONS

A decrease in brain volume following mild traumatic brain injury is detectable on CT and is not seen in similar patients with non-mild traumatic brain injury during a similar timeframe. Given the stability of brain volume before mild traumatic brain injury, CT volume loss may represent the subtle effects of neurodegeneration.

PET and Single-Photon Emission Computed Tomography in Brain Concussion

This article offers an overview of the application of PET and single photon emission computed tomography brain imaging to concussion, a type of mild traumatic brain injury and traumatic brain injury, in general. The article reviews the application of these neuronuclear imaging modalities in cross-sectional and longitudinal studies. Additionally, this article frames the current literature with an overview of the basic physics and radiation exposure risks of each modality.

Validation of the Pediatric NEXUS II Head Computed Tomography Decision Instrument for Selective Imaging of Pediatric Patients with Blunt Head Trauma

BACKGROUND

Data suggest that clinicians, when evaluating pediatric patients with blunt head trauma, may be overordering head computed tomography (CT). Prior decision instruments (DIs) aimed at aiding clinicians in safely forgoing CTs may be paradoxically increasing CT utilization. This study evaluated a novel DI that aims for high sensitivity while also improving specificity over prior instruments.

METHODS

We conducted a planned secondary analysis of the NEXUS Head CT DI among patients less than 18 years old. The rule required patients satisfy seven criteria to achieve "low-risk" classification. Patients were assigned "high-risk" status if they fail to meet one or more criteria. Our primary outcome was the ability of the rule to identify all patients requiring neurosurgical intervention.

RESULTS

The study enrolled 1,018 blunt head injury pediatric patients. The DI assigned high-risk status to 27 of 27 patients requiring neurosurgical intervention (sensitivity = 100.0%, 95% confidence interval [CI] = 87.2%-100%]). The instrument assigned low-risk status to 330 of 991 patients who did not require neurosurgical intervention (specificity = 33.3%, 95% CI = 30.3%-36.3%). None of the 991 low-risk patients required neurosurgical intervention (negative predictive value [NPV] = 100%, 95% CI = 99.6%-100%). The DI correctly assigned high-risk status to 48 of the 49 patients with significant intracranial injuries, yielding a sensitivity of 98.0% (95% CI = 89.1%-99.9%). The instrument assigned low-risk status to 329 of 969 patients who did not have significant injuries to yield a specificity of 34.0% (95% CI = 31.0%-37.0%). Significant injuries were absent in 329 of the 330 patients assigned low-risk status to yield a NPV of 99.7% (95% CI = 98.3%-100%).

CONCLUSIONS

The Pediatric NEXUS Head CT DI reliably identifies blunt trauma patients who require head CT imaging and could significantly reduce the use of CT imaging.