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Cocaine is the second most commonly abused illicit drug in the US and the most common one involved in emergency department visits, the majority of which are related to the cardiovascular system. Cardiovascular complications related with cocaine abuse include myocardial ischemia and infarction, myocarditis, hypertrophic cardiomyopathy, dilated cardiomyopathy, aortic dissection, thrombosis, stroke and cerebral hemorrhage, and different forms of visceral ischemia, among others. In an era where cocaine use has reached epidemic proportions, it is necessary for the radiologist to understand the pathophysiology, clinical presentation, and imaging characteristics of its cardiovascular complications. [ABSTRACT FROM AUTHOR]

Methadone is an opiate used as part of the treatment for heroin abuse; it can be ingested orally. We present the lethal outcome of a 22-month-old child intoxicated after methadone ingestion. [ABSTRACT FROM AUTHOR]

Background and Objectives: Maximizing the extent of resection (EOR) improves outcomes in glioblastoma (GBM). However, previous GBM studies have not addressed the EOR impact in molecular subgroups beyond IDH1/IDH2 status. In the current article, we evaluate whether EOR confers a benefit in all GBM subtypes or only in particular molecular subgroups., Methods: A retrospective cohort of newly diagnosed GBM isocitrate dehydrogenase (IDH)-wildtype undergoing resection were prospectively included in a database (n = 138). EOR and residual tumor volume (RTV) were quantified with semiautomated software. Formalin-fixed paraffin-embedded tumor tissues were analyzed by targeted next-generation sequencing. The association between recurrent genomic alterations and EOR/RTV was evaluated using a recursive partitioning analysis to identify thresholds of EOR or RTV that may predict survival. The Kaplan-Meier methods and multivariable Cox proportional hazards regression methods were applied for survival analysis., Results: Patients with EOR ≥88% experienced 44% prolonged overall survival (OS) in multivariable analysis (hazard ratio: 0.56, P = .030). Patients with alterations in the TP53 pathway and EOR <89% showed reduced OS compared to TP53 pathway altered patients with EOR>89% (10.5 vs 18.8 months; HR: 2.78, P = .013); however, EOR/RTV was not associated with OS in patients without alterations in the TP53 pathway. Meanwhile, in all patients with EOR <88%, PTEN -altered had significantly worse OS than PTEN -wildtype (9.5 vs 15.4 months; HR: 4.53, P < .001)., Conclusion: Our results suggest that a subset of molecularly defined GBM IDH-wildtype may benefit more from aggressive resections. Re-resections to optimize EOR might be beneficial in a subset of molecularly defined GBMs. Molecular alterations should be taken into consideration for surgical treatment decisions in GBM IDH-wildtype., (Copyright © Congress of Neurological Surgeons 2024. All rights reserved.)

Diagnosing and differentiating spinal vascular pathologic conditions is challenging. Small structures, lengthy imaging examinations, and overlapping imaging features increase the difficulty. Yet, subtle findings and helpful protocols can narrow the differential diagnosis. The authors aim to help radiologists make accurate and timely diagnoses of spinal vascular pathologic conditions in and around the spinal cord by highlighting spinal vascular anatomy, imaging findings, and three broad categories of abnormalities: infarcts, anomalies, and tumors. © RSNA, 2024.

Objectives: Glioblastomas (GBM) are the most common primary invasive neoplasms of the brain. Distinguishing between lesion recurrence and different types of treatment related changes in patients with GBM remains challenging using conventional MRI imaging techniques. Therefore, accurate and precise differentiation between true progression or pseudoresponse is crucial in deciding on the appropriate course of treatment. This retrospective study investigated the potential of apparent diffusion coefficient (ADC) map values derived from diffusion-weighted imaging (DWI) as a noninvasive method to increase diagnostic accuracy in treatment response., Methods: A cohort of 21 glioblastoma patients (mean age: 59.2 ± 11.8, 12 Male, 9 Female) that underwent treatment with bevacizumab were selected. The ADC values were calculated from the DWI images obtained from a standardized brain protocol across 1.5-T and 3-T MRI scanners. Ratios were calculated for rADC values. Lesions were classified as bevacizumab-induced cytotoxicity based on characteristic imaging features (well-defined regions of restricted diffusion with persistent diffusion restriction over the course of weeks without tissue volume loss and absence of contrast enhancement). The rADC value was compared to these values in radiation necrosis and recurrent lesions, which were concluded in our prior study. The nonparametric Wilcoxon signed rank test with p < 0.05 was used for significance., Results: The mean ± SD age of the selected patients was 59.2 ± 11.8. ADC values and corresponding mean rADC values for bevacizumab-induced cytotoxicity were 248.1 ± 67.2 and 0.39 ± 0.10, respectively. These results were compared to the ADC values and corresponding mean rADC values of tumor progression and radiation necrosis. Significant differences between rADC values were observed in all three groups ( p < 0.001). Bevacizumab-induced cytotoxicity had statistically significant lower ADC values compared to both tumor recurrence and radiation necrosis., Conclusion: The study demonstrates the potential of ADC values as noninvasive imaging biomarkers for differentiating recurrent glioblastoma from radiation necrosis and bevacizumab-induced cytotoxicity.

Spinal extradural tumors, although uncommon, have high morbidity and mortality rates. Radiographs and computed tomography scans are typically used to assess and determine the characteristics of these tumors. However, MR imaging is the preferred method for the evaluation of complications that can increase morbidity, such as spinal cord and nerve compression. Imaging features, such as type of matrix, cortical involvement, and margins, aid in determining the diagnosis. This article discusses common and infrequent extradural spinal tumors, their imaging characteristics, and how age, location, and clinical presentation help in diagnosing these neoplasms., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Blunt and penetrating vascular injuries of the head and neck can represent life-threatening emergencies that require accurate detection to prevent devastating and long-lasting consequences. Implementing appropriate screening criteria to indicate imaging studies is crucial as there is a variable latent time before the onset of clinical manifestations. Computed tomography angiography, MR imaging, and digital subtraction angiography represent the imaging modalities of choice to evaluate vascular injuries. The aim of this review is to provide a description of the different types of vascular injuries, describe the importance of each imaging modality, and recognize the imaging appearance of traumatic vessel injury., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Purpose: American football is considered one of the more injury-prone sports given its high-speed and high-impact nature. While much attention has been focused on chronic traumatic encephalopathy, spinal injuries represent the most common catastrophic injury incurred in football. The goal of this investigation is to describe the most common football-associated spinal lesions in a multi-center health system., Methods: This is a retrospective analysis of patients with imaging evidence of spinal injuries related to American football during a 10-year period. Injuries were classified based on the anatomic level, type injury, spinal cord compromise, and therapeutic management. Chi-squared and Fisher's exact test were used for statistical analysis of categorial variables, and simple logistic regression was used to determine individual odds ratios., Results: A total of 71 patients were included, with a median age of 17 (IQR, 15-22) years. The cervical spine was the most frequently affected segment (46%), followed by lumbar spine injuries (45%), and thoracic spine injuries (10%). Discogenic injuries were identified in 45 patients (63%). Spinal cord injury was documented in 7 subjects (10%), while cauda equina compression was reported in 1 patient (1%)., Conclusions: Acute spinal injuries continue to represent a significant cause of morbidity among American football players. Compared to national statistics, we found a similar distribution of spinal injuries in terms of anatomic location and an alarmingly high proportion of SCI. This investigation represents the largest single-center study addressing spinal injuries among football players., (© 2022. The Author(s), under exclusive licence to American Society of Emergency Radiology (ASER).)

Purpose: Traumatic spondylolisthesis of the axis (TSA) with bilateral pars interarticularis fracture (a pattern also known as Hangman's fractures) accounts for 4-5% of all cervical fractures. Various classification systems have been described to assist therapeutic decision-making. The goal is to reassess the utility of these classifications for treatment strategy and evaluate additional imaging associations., Methods: This is an IRB approved, retrospective analysis of patients with imaging diagnosis of TSA from 2016 to 2019. Consensus reads were performed classifying TSA into various Levine and Edwards subtypes and typical vs. atypical fractures. Other imaging findings such as additional cervical fractures, traumatic brain injury, spinal cord injury, and vertebral artery injury were recorded. Treatment strategy and outcome were reviewed from clinical charts. Fisher exact test was used for statistical analysis., Results: A total of 58 patients were included, with a mean age of 62.7 ± 25 years, and male to female ratio of 1:1.2. Motor vehicle collision was the most common cause of TSA. Type I and III injuries were the most and the least common injuries, respectively. Patients with type I injuries were found to have good healing rates with conservative management (p < 0.001) while type IIa and III injuries were managed with surgical stabilization (p = 0.04 and p = 0.01, respectively). No statistical difference was observed in the treatment strategy for type II fractures (p = 0.12) and its prediction of the associated injuries. Atypical fractures were not found to have a higher incidence of SCI (p = 0.31). A further analysis revealed significantly higher-grade vertebral artery injuries (grades III and IV according to Biffl grading) in patients with type IIa and III injuries (p = 0.001) and an 11-fold increased risk of TBI compared to type I and type II fractures (p = 0.013)., Conclusion: TSA fracture types were not associated with any clinical outcome. Levine and Edwards type II classification itself is not enough to guide the treatment plan and does not account for associated injuries. Additional imaging markers may be needed., (© 2022. The Author(s), under exclusive licence to American Society of Emergency Radiology (ASER).)

The use of artificial intelligence (AI) algorithms in the field of radiology is becoming more common. Several studies have demonstrated the potential utility of machine learning (ML) and deep learning (DL) techniques as aids for radiologists to solve specific radiological challenges. The decision-making process, the establishment of specific clinical or radiological targets, the profile of the different professionals involved in the development of AI solutions, and the relation with partnerships and stakeholders are only some of the main issues that have to be faced and solved prior to starting the development of radiological AI solutions. Among all the players in this multidisciplinary team, the communication between radiologists and data scientists is essential for a successful collaborative work. There are specific skills that are inherent to radiological and medical training that are critical for identifying anatomical or clinical targets as well as for segmenting or labelling lesions. These skills would then have to be transferred, explained, and taught to the data science experts to facilitate their comprehension and integration into ML or DL algorithms. On the other hand, there is a wide range of complex software packages, deep neural-network architectures, and data transfer processes for which radiologists need the expertise of software engineers and data scientists in order to select the optimal manner to analyse and post-process this amount of data. This paper offers a summary of the top five challenges faced by radiologists and data scientists including tips and tricks to build a successful AI team., (Copyright © 2020 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.)

We describe a case series of imaging findings of 4 patients who underwent spinal dysraphisms repair in utero with novel patch material, cryopreserved human umbilical cord, in our institution. In our study, the prenatal and postnatal magnetic resonance imaging and ultrasound are reviewed and showed cord tethering and syrinx progression in all cases. Our report is the first description of magnetic resonance imaging and ultrasound findings in the context of using this novel patch in severe cases of spinal dysraphisms.

Background and Purpose: While third ventricular colloid cysts may present as an incidental finding, they also harbor the potential to cause ventricular obstruction and sudden death. Herein we analyze the relationship between imaging appearance and the risk of obstructive ventriculomegaly., Materials and Methods: This is a retrospective review of the MR imaging appearance of 64 patients with colloid cysts, 46 of whom also had a CT scan, obtained by a tertiary hospital imaging report data base search over a 10-year period. Cysts were categorized by appearance on T2-FLAIR and correlated with patient age, cyst size, and the risk of obstructive ventriculomegaly. Histopathologic correlation was available for 28 cases., Results: The 64-patient cohort was 52% female, median age 50 years (range 10 to 99 years). Cysts hyperintense on T2-FLAIR (53.1%) were larger ( P <.001), occurred in younger patients ( P = .01), and had a higher risk of obstructive ventriculomegaly than homogeneously hypointense cysts (relative risk 6.18, 95% CI [2.04, 18.67]). Three patterns of T2 hyperintensity were identified: homogeneously hyperintense, hyperintense rim, and cysts with "dot sign." Although "dot sign" cysts were larger ( P < .001), there was no significant difference in patient age or the risk of ventricular obstruction among T2 hyperintense cysts. Cyst wall histopathology did not vary with imaging appearance., Conclusions: Hyperintensity on T2-FLAIR, whether homogeneous, rim, or "dot sign," is associated with larger cyst size and younger patient age, and is an imaging risk factor for obstructive ventriculomegaly. The hyperintense rim does not represent a thickened cyst wall., (© 2020 by American Journal of Neuroradiology.)

Posterior globe flattening has been well-documented in astronauts both during and after long-duration space flight (LDSF) and has been observed as early as 10 days into a mission on the International Space Station. Globe flattening (GF) is thought to be caused by the disc centred anterior forces created by elevated volume and/or pressure within the optic nerve sheath (ONS). This might be the result of increased intracranial pressure, increased intraorbital ONS pressure from compartmentalisation or a combination of these mechanisms. We report posterior GF in three astronauts that has persisted for 7 years or more following their return from LDSFs suggesting that permanent scleral remodelling may have occurred., (© 2020 Taylor & Francis Group, LLC.)

Background and Purpose: Clinical and imaging manifestations of idiopathic intracranial hypertension should prompt early diagnosis and treatment to avoid complications. Multiple diagnostic imaging criteria are reported to suggest the diagnosis of idiopathic intracranial hypertension with questionable sensitivity and/or specificity. Increased intracranial pressure results in dilation of the perineural cisternal spaces such as the optic nerve sheaths and the Meckel cave. It may also cause protrusion of cisternal structures of the Meckel cave through the skull base foramina, which could result in indentation or a bilobed appearance of the Meckel cave. We investigated the changes in the Meckel cave in patients with proved idiopathic intracranial hypertension versus healthy controls., Materials and Methods: We studied 75 patients with a diagnosis of idiopathic intracranial hypertension and 75 age-and sex-matched healthy controls. The transverse diameter of Meckel cave was measured in the axial and coronal planes of T2-weighted MR imaging sequences, and comparison was made between the 2 groups., Results: The mean diameters of the Meckel cave on the coronal T2 plane in patients with idiopathic intracranial hypertension were 5.21  ± 1.22 mm on the right side and 5.16  ± 0.90 mm on the left side, while in the control group, they measured 3.89  ± 0.62 mm and 4.09  ± 0.68 mm, respectively ( P value < .001). Of 75 patients with an approved diagnosis of idiopathic intracranial hypertension, 57 (76%) showed an indented Meckel cave as opposed to 21 (28%) in the control group., Conclusions: Our results confirm for the first time that the shape and size of the Meckel cave can be used as sensitive and specific diagnostic imaging markers for the diagnosis of idiopathic intracranial hypertension., (© 2020 by American Journal of Neuroradiology.)

Introduction/purpose: Though spinal fractures constitute a minority of all traumas, the financial burden imposed is immense especially following cervical spine trauma. There have been several papers in the past describing the incidence of cervical spine fractures. In this paper, we report the incidence of cervical spine fractures and correlate with demographic information and cause of injury and review the mechanism of fractures., Materials and Methods: We performed retrospective analysis of 934 patients who had undergone CT scan for cervical spine trauma at our institute which includes 16 hospitals and one level I trauma center over a period of 2 years. This list was created from a wider database of 13,512 patients imaged for suspected cervical spine injury. All patients who had at least one positive finding on CT were included in this study irrespective of any demographic difference. Each patient was analyzed by reviewing the medical records, and correlation was sought between demographics and cause of injury., Results: In our study, the peak incidence of cervical spine trauma was in the age group of 21-30 years followed by 31-40 years with a male:female ratio of 2.1. The major cause of injury in the study population was motor vehicle accidents (66.1%), followed by fall from height of less than 8 ft (12.2%). With regard to the ethnic distribution, Caucasians (46.9%) constituted the major population followed by Hispanic population (23.3%). C1 and C2 were observed to be more frequently fractured as compared with the subaxial spine. Incidence of C2 fractures (188 levels) was higher as compared with C1 (102 levels). Incidence of body and lateral mass fractures was marginally higher as compared with odontoid fractures. C7 (50 levels) was the most fractured vertebral body in the subaxial spine followed by C6 (35 levels) and C5., Conclusion: Spinal trauma is on the rise and it helps to know the factors which can guide us for better management of these patients. We can utilize these results to prognosticate and streamline clinical management of these patients.

Objective: Our objective is to document the imaging appearance in the intracranial compartment at the time of the infants' first postnatal brain MR imaging after fetal repair for spinal dysraphisms., Methods: Twenty-nine patients were evaluated on fetal and postnatal magnetic resonance imaging for a series of features of Chiari II malformation., Results: Of the 29 infants, 55% had resolution of tonsillar ectopia, and 62% showed a dorsal outpouching of the near the foramen magnum on postnatal magnetic resonance imaging. The majority had persistence of Chiari II features including: prominent massa intermedia (93%), tectal beaking (93%), towering cerebellum (55%), flattening of the fourth ventricle (90%), hypoplastic tentorium (97%), and tonsillar hypoplasia (59%)., Conclusions: Normally positioned or minimally descended, oftentimes hypoplastic tonsils in the presence of a posterior fossa configuration typical of Chiari II, was the most common presentation. An additional documented feature was an outpouching of the dorsal thecal sac between the opisthion and the posterior arch of C1.

Importance: The efficacy and safety of endovascular thrombectomy (EVT) in patients with large ischemic cores remains unknown, to our knowledge., Objective: To compare outcomes in patients with large ischemic cores treated with EVT and medical management vs medical management alone., Design, Setting, and Participants: This prespecified analysis of the Optimizing Patient's Selection for Endovascular Treatment in Acute Ischemic Stroke (SELECT) trial, a prospective cohort study of imaging selection that was conducted in 9 US comprehensive stroke centers, enrolled patients between January 2016 and February 2018, and followed them up for 90 days. Patients with moderate to severe stroke and anterior circulation large-vessel occlusion presenting up to 24 hours from the time they were last known to be well were eligible for the cohort. Of these, patients with large ischemic cores on computed tomography (CT) (Alberta Stroke Program Early CT Score <6) or CT perfusion scanning (a volume with a relative cerebral blood flow <30% of ≥50 cm3) were included in analyses., Exposures: Endovascular thrombectomy with medical management (MM) or MM only., Main Outcomes and Measures: Functional outcomes at 90 days per modified Rankin scale; safety outcomes (mortality, symptomatic intracerebral hemorrhage, and neurological worsening)., Results: A total of 105 patients with large ischemic cores on either CT or CT perfusion images were included: 71 with Alberta Stroke Program Early CT Scores of 5 or less (EVT, 37; MM, 34), 74 with cores of 50 cm3 or greater on CT perfusion images (EVT, 39; MM, 35), and 40 who had large cores on both CT and CT perfusion images (EVT, 14; MM, 26). The median (interquartile range) age was 66 (60-75) years; 45 patients (43%) were female. Nineteen of 62 patients (31%) who were treated with EVT achieved functional independence (modified Rankin Scale scores, 0-2) vs 6 of 43 patients (14%) treated with MM only (odds ratio [OR], 3.27 [95% CI, 1.11-9.62]; P = .03). Also, EVT was associated with better functional outcomes (common OR, 2.12 [95% CI, 1.05-4.31]; P = .04), less infarct growth (44 vs 98 mL; P = .006), and smaller final infarct volume (97 vs 190 mL; P = .001) than MM. In the odds of functional independence, there was a 42% reduction per 10-cm3 increase in core volume (adjusted OR, 0.58 [95% CI, 0.39-0.87]; P = .007) and a 40% reduction per hour of treatment delay (adjusted OR, 0.60 [95% CI, 0.36-0.99]; P = .045). Of 10 patients who had EVT with core volumes greater than 100 cm3, none had a favorable outcome., Conclusions and Relevance: Although the odds of good outcomes for patients with large cores who receive EVT markedly decline with increasing core size and time to treatment, these data suggest potential benefits. Randomized clinical trials are needed.

Objective: For research and risk factor analysis, a reproducible method quantifying atherosclerosis is necessary. Our aim was to develop a computed tomography (CT) angiography grading system to quantify atherosclerotic disease of the head and neck., Methods: Institutional review board-approved, retrospective analysis was performed on 152 patients who underwent head/neck CT angiography. A grading scale was designed to calculate plaque burden at multiple sites with the sum referred to as atherosclerosis score. Three radiologists calculated scores with an overlap of cases to calculate the intraclass correlation coefficient., Results: Without any prior training, the intraclass correlation coefficient between readers was considered fair. After a short tutorial, intraclass correlation coefficient was recalculated using separate patients, showing excellent correlation.Statistically significant positive correlation was found between atherosclerosis scale and age, hyperlipidemia, hypertension, and diabetes, but no correlation with sex or smoking status., Conclusions: A simple, visual grading scale for atherosclerosis in head/neck CT angiography was used to standardize reporting and better characterize a patient's risk of stroke.

Purpose of Review: Cerebral radiation necrosis (CRN) is a major dose-limiting adverse event of radiotherapy. The incidence rate of RN varies with the radiotherapy modality, total dose, dose fractionation, and the nature of the lesion being targeted. In addition to these known and controllable features, there is a stochastic component to the occurrence of CRN-the genetic profile of the host or the lesion and their role in the development of CRN., Recent Findings: Recent studies provide some insight into the genetic mechanisms underlying radiation-induced brain injury. In addition to these incompletely understood host factors, the diagnostic criteria for CRN using structural and functional imaging are also not clear, though multiple structural and functional imaging modalities exist, a combination of which may prove to be the ideal diagnostic imaging approach. As the utilization of novel molecular therapies and immunotherapy increases, the incidence of CNR is expected to increase and its diagnosis will become more challenging. Tissue biopsies can be insensitive and suffer from sampling biases and procedural risks. Liquid biopsies represent a promising, accurate, and non-invasive diagnostic strategy, though this modality is currently in its infancy. A better understanding of the pathogenesis of CRN will expand and optimize the diagnosis and management of CRN by better utilizing existing treatment options including bevacizumab, pentoxifylline, hyperbaric oxygen therapy, and laser interstitial thermal therapy.

The advent of magnetic resonance imaging has improved our understanding of the pathophysiology and natural course of multiple sclerosis (MS). The ability of magnetic resonance imaging to show the evolution of MS lesions on sequential scans has brought it to be one of the endpoints in clinical trials for disease-modifying therapies. Based on the most updated consensus guidelines from the American (Consortium of MS Centers) and European (Magnetic Resonance Imaging in MS) boards of experts in MS, this document shows the most relevant landmarks related to imaging findings, diagnostic criteria, indications to obtain a magnetic resonance, scan protocols and sequence options for patients with MS. Although incorporating the knowledge derived from the research arena into the daily clinical practice is always challenging, in this article, the authors provide useful recommendations to improve the information contained in the magnetic resonance report oriented to facilitate communication between radiologists and specialized medical teams involved in MS patients' multidisciplinary care.

Background: Meningiomas are the most common primary intracranial tumors. The current diagnosis and treatment of meningioma is dependent on computed tomography and magnetic resonance imaging, with follow-up management relying mainly on magnetic resonance imaging. The limitations of these structural imaging modalities include delineation of the tumor extent, tumor grade, and differentiation from other meningioma mimickers, especially in or around the skull base. Because studies with positron emission tomography (PET) have shown that PET is able to fulfill some of these gaps, the use of PET for meningiomas has been steadily increasing. Fluciclovine, also known as anti-1-amino-3-[ 18 F]-fluorocyclobutane-1-carboxylic acid (Axumin), is a new PET radiotracer approved by the Food and Drug Administration in 2016 for the detection of suspected recurrent prostate cancer with elevated prostate-specific antigen levels. Because the radiotracer is new, very little is known about the utility of this tracer in brain tumors., Case Description: We present 3 cases of meningioma with avid uptake of fluciclovine. In each of these cases, the meningioma was incidentally found during surveillance using PET imaging in patients with prostate cancer., Conclusions: These cases illustrate that this new radiotracer has the potential to be a complementary tool in the meningioma workup, treatment, and follow-up, especially for skull base lesions., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The aim of this study is to evaluate whether we could develop a machine learning method to distinguish models of cerebrospinal fluid shunt valves (CSF-SVs) from their appearance in clinical X-rays. This is an essential component of an automatic MRI safety system based on X-ray imaging. To this end, a retrospective observational study using 416 skull X-rays from unique subjects retrieved from a clinical PACS system was performed. Each image included a CSF-SV representing the most common brands of programmable shunt valves currently used in US which were split into five different classes. We compared four machine learning pipelines: two based on engineered image features (Local Binary Patterns and Histogram of Oriented Gradients) and two based on features learned by a deep convolutional neural network architecture. Performance is evaluated using accuracy, precision, recall and f1-score. Confidence intervals are computed with non-parametric bootstrap procedures. Our best performing method identified the valve type correctly 96% [CI 94-98%] of the time (CI: confidence intervals, precision 0.96, recall 0.96, f1-score 0.96), tested using a stratified cross-validation approach to avoid chances of overfitting. The machine learning pipelines based on deep convolutional neural networks showed significantly better performance than the ones based on engineered image features (mean accuracy 95-96% vs. 56-64%). This study shows the feasibility of automatically distinguishing CSF-SVs using clinical X-rays and deep convolutional neural networks. This finding is the first step towards an automatic MRI safety system for implantable devices which could decrease the number of patients that experience denials or delays of their MRI examinations.

Purpose: Spaceflight negatively affects sensorimotor behavior; exercise mitigates some of these effects. Head down tilt bed rest (HDBR) induces body unloading and fluid shifts, and is often used to investigate spaceflight effects. Here, we examined whether exercise mitigates effects of 70 days HDBR on the brain and if fitness and brain changes with HDBR are related., Methods: HDBR subjects were randomized to no-exercise (n = 5) or traditional aerobic and resistance exercise (n = 5). Additionally, a flywheel exercise group was included (n = 8). Exercise protocols for exercise groups were similar in intensity, therefore these groups were pooled in statistical analyses. Pre and post-HDBR MRI (structure and structural/functional connectivity) and physical fitness measures (lower body strength, muscle cross sectional area, VO2 max, body composition) were collected. Voxel-wise permutation analyses were used to test group differences in brain changes, and their associations with fitness changes., Results: Comparisons of exercisers to controls revealed that exercise led to smaller fitness deterioration with HDBR but did not affect brain volume or connectivity. Group comparisons showed that exercise modulated post-HDBR recovery of brain connectivity in somatosensory regions. Posthoc analysis showed that this was related to functional connectivity decrease with HDBR in non-exercisers but not in exercisers. Correlational analyses between fitness and brain changes showed that fitness decreases were associated with functional connectivity and volumetric increases (all r >.74), potentially reflecting compensation. Modest brain changes or even decreases in connectivity and volume were observed in subjects who maintained or showed small fitness gains. These results did not survive Bonferroni correction, but can be considered meaningful because of the large effect sizes., Conclusion: Exercise performed during HDBR mitigates declines in fitness and strength. Associations between fitness and brain connectivity and volume changes, although unadjusted for multiple comparisons in this small sample, suggest that supine exercise reduces compensatory HDBR-induced brain changes., Competing Interests: Support from KBRwyle in the form of salaries (MED, YED, NEG, IK, and APM) did not alter our adherence to PLOS ONE policies on sharing data and materials.

Introduction Orbital meningoencephalocele formation is primarily a result of congenital defects in the pediatric population and trauma of the anterior cranial fossa in adults. We present a unique case of nontraumatic nasal and orbital meningoencephaloceles presenting as bilateral proptosis with exotropia secondary to chronic hydrocephalus. Clinical presentation A 20-year-old male with a history of tuberous sclerosis, X-linked intellectual disability, and epilepsy presented to the emergency department with two days of nausea, emesis, seizures, and two months of progressive proptosis. Initial radiographs of the skull showed a "copper beaten" appearance, indicating chronically elevated intracranial pressure. Computed tomography imaging of the head demonstrated bilateral defects in the cribriform plate and anterior cranial fossa. Magnetic resonance imaging of the brain revealed triventricular hydrocephalus with meningoencephalocele extension into the nasal cavity and frontal horn herniation into the extraconal space of the orbits. The hydrocephalus was managed with ventriculoperitoneal shunt placement with rapid and complete resolution of the proptosis. Conclusion No reports have described bilateral proptosis as the presenting finding of orbital and nasal meningoencephaloceles in the absence of trauma or congenital defect. This case study demonstrates the management of meningoencephalocele formation secondary to chronic hydrocephalus.

Head-down-tilt bed rest (HDBR) is frequently utilized as a spaceflight analog research environment to study the effects of axial body unloading and fluid shifts that are associated with spaceflight in the absence of gravitational modifications. HDBR has been shown to result in balance changes, presumably due to sensory reweighting and adaptation processes. Here, we examined whether HDBR results in changes in the neural correlates of vestibular processing. Thirteen men participated in a 70-day HDBR intervention; we measured balance, functional mobility, and functional brain activity in response to vestibular stimulation at 7 time points before, during, and after HDBR. Vestibular stimulation was administered by means of skull taps, resulting in activation of the vestibular cortex and deactivation of the cerebellar, motor, and somatosensory cortices. Activation in the bilateral insular cortex, part of the vestibular network, gradually increased across the course of HDBR, suggesting an upregulation of vestibular inputs in response to the reduced somatosensory inputs experienced during bed rest. Furthermore, greater increase of activation in multiple frontal, parietal, and occipital regions in response to vestibular stimulation during HDBR was associated with greater decrements in balance and mobility from before to after HDBR, suggesting reduced neural efficiency. These findings shed light on neuroplastic changes occurring with conditions of altered sensory inputs, and reveal the potential for central vestibular-somatosensory convergence and reweighting with bed rest., (© 2018 Wiley Periodicals, Inc.)

Head-down tilt bed rest (HDBR) has been used as a spaceflight analog to study some of the effects of microgravity on human physiology, cognition, and sensorimotor functions. Previous studies have reported declines in balance control and functional mobility after spaceflight and HDBR. In this study we investigated how the brain activation for foot movement changed with HDBR. Eighteen healthy men participated in the current HDBR study. They were in a 6° head-down tilt position continuously for 70 days. Functional MRI scans were acquired to estimate brain activation for foot movement before, during, and after HDBR. Another 11 healthy men who did not undergo HDBR participated as control subjects and were scanned at four time points. In the HDBR subjects, the cerebellum, fusiform gyrus, hippocampus, and middle occipital gyrus exhibited HDBR-related increases in activation for foot tapping, whereas no HDBR-associated activation decreases were found. For the control subjects, activation for foot tapping decreased across sessions in a couple of cerebellar regions, whereas no activation increase with session was found. Furthermore, we observed that less HDBR-related decline in functional mobility and balance control was associated with greater pre-to-post HDBR increases in brain activation for foot movement in several cerebral and cerebellar regions. Our results suggest that more neural control is needed for foot movement as a result of HDBR. NEW & NOTEWORTHY Long-duration head-down bed rest serves as a spaceflight analog research environment. We show that brain activity in the cerebellum and visual areas during foot movement increases from pre- to post-bed rest and then shows subsequent recovery. Greater increases were seen for individuals who exhibited less decline in functional mobility and balance control, suggestive of adaptive changes in neural control with long-duration bed rest.

Background and Purpose: As part of its technological sophistication, the International Space Station (ISS) Program operates a robust medical surveillance schedule for its rotating 6-person crew to control the known health risks and to address knowledge gaps related to human health in space flight environment. Recent evidence on visual impairment in a subset of ISS crew has renewed the interest in the effects of long-duration space flight on the central nervous system (CNS). Through retrospective analysis in a sample of 10 healthy astronauts, we demonstrate the utility of multimodal quantitative magnetic resonance imaging (qMRI) with diffusion tensor imaging (DTI)-based customized brain templates to examine the structural attributes of various CNS compartments in this occupational group., Methods: The study included 10 healthy astronauts (45-55 years). All subjects had previous space flights with the median duration of 110 days. Multimodal quantitative structural imaging modalities performed and used in analyses., Results: A host of CNS features are presented, which are largely commensurate with the available normative data. Remarkably, some of our findings demonstrate statistically significant positive features suggestive of structural neuroplasticity conceivably associated with the professional activities of astronauts, and compensatory neurogenesis that counterweighs the expected normative volume loss with age., Conclusions: The novelty of this exploratory report is in the demonstration of a qMRI toolset as a potential capability for characterization and surveillance of unique professional groups, and for future prospective examinations of the effects of various long-term exposures on CNS., (Copyright © 2018 by the American Society of Neuroimaging.)

Conventional imaging findings in patients with cerebral concussion and chronic traumatic encephalopathy are absent or subtle in the majority of cases. The most common abnormalities include cerebral volume loss, enlargement of the cavum of the septum pellucidum, cerebral microhemorrhages, and white matter signal abnormalities, all of which have poor sensitivity and specificity. Advanced imaging modalities, such as diffusion tensor imaging (DTI), blood oxygen level dependent functional MR Imaging (BOLD fMRI), MR spectroscopy, perfusion imaging, positron emission tomography (PET), single photon emission computed tomography (SPECT), and magnetoencephalography detect physiologic abnormalities in symptomatic patients and, although currently in the investigation phase, may become useful in the clinical arena., (Published by Elsevier Inc.)

Background: Adverse effects of spaceflight on sensorimotor function have been linked to altered somatosensory and vestibular inputs in the microgravity environment. Whether these spaceflight sequelae have a central nervous system component is unknown. However, experimental studies have shown spaceflight-induced brain structural changes in rodents' sensorimotor brain regions. Understanding the neural correlates of spaceflight-related motor performance changes is important to ultimately develop tailored countermeasures that ensure mission success and astronauts' health., Method: Head down-tilt bed rest (HDBR) can serve as a microgravity analog because it mimics body unloading and headward fluid shifts of microgravity. We conducted a 70-day 6° HDBR study with 18 right-handed males to investigate how microgravity affects focal gray matter (GM) brain volume. MRI data were collected at 7 time points before, during and post-HDBR. Standing balance and functional mobility were measured pre and post-HDBR. The same metrics were obtained at 4 time points over ~90 days from 12 control subjects, serving as reference data., Results: HDBR resulted in widespread increases GM in posterior parietal regions and decreases in frontal areas; recovery was not yet complete by 12 days post-HDBR. Additionally, HDBR led to balance and locomotor performance declines. Increases in a cluster comprising the precuneus, precentral and postcentral gyrus GM correlated with less deterioration or even improvement in standing balance. This association did not survive Bonferroni correction and should therefore be interpreted with caution. No brain or behavior changes were observed in control subjects., Conclusions: Our results parallel the sensorimotor deficits that astronauts experience post-flight. The widespread GM changes could reflect fluid redistribution. Additionally, the association between focal GM increase and balance changes suggests that HDBR also may result in neuroplastic adaptation. Future studies are warranted to determine causality and underlying mechanisms.

The neural correlates of spaceflight-induced sensorimotor impairments are unknown. Head down-tilt bed rest (HDBR) serves as a microgravity analog because it mimics the headward fluid shift and axial body unloading of spaceflight. We investigated focal brain white matter (WM) changes and fluid shifts during 70 days of 6° HDBR in 16 subjects who were assessed pre (2x), during (3x), and post-HDBR (2x). Changes over time were compared to those in control subjects (n = 12) assessed four times over 90 days. Diffusion MRI was used to assess WM microstructure and fluid shifts. Free-Water Imaging was used to quantify distribution of intracranial extracellular free water (FW). Additionally, we tested whether WM and FW changes correlated with changes in functional mobility and balance measures. HDBR resulted in FW increases in fronto-temporal regions and decreases in posterior-parietal regions that largely recovered by two weeks post-HDBR. WM microstructure was unaffected by HDBR. FW decreases in the post-central gyrus and precuneus correlated negatively with balance changes. We previously reported that gray matter increases in these regions were associated with less HDBR-induced balance impairment, suggesting adaptive structural neuroplasticity. Future studies are warranted to determine causality and underlying mechanisms.