Comparison of Continuous Intracortical and Scalp Electroencephalography in Comatose Patients with Acute Brain Injury.

BACKGROUND: Depth electroencephalography (dEEG) is a recent invasive monitoring technique used in patients with acute brain injury. This study aimed to describe in detail the clinical manifestations of nonconvulsive seizures (NCSzs) with and without a surface EEG correlate, analyze their long-standing effects, and provide data that contribute to understanding the significance of certain scalp EEG patterns observed in critically ill patients. METHODS: We prospectively enrolled a cohort of 33 adults with severe acute brain injury admitted to the neurological intensive care unit. All of them underwent multimodal invasive monitoring, including dEEG. All patients were scanned on a 3T magnetic resonance imaging scanner at 6 months after hospital discharge, and mesial temporal atrophy (MTA) was calculated using a visual scale. RESULTS: In 21 (65.6%) of 32 study participants, highly epileptiform intracortical patterns were observed. A total of 11 (34.3%) patients had electrographic or electroclinical seizures in the dEEG, of whom 8 had both spontaneous and stimulus-induced (SI) seizures, and 3 patients had only spontaneous intracortical seizures. An unequivocal ictal scalp correlate was observed in only 3 (27.2%) of the 11 study participants. SI-NCSzs occurred during nursing care, medical procedures, and family visits. Subtle clinical manifestations, such as restlessness, purposeless stereotyped movements of the upper limbs, ventilation disturbances, jerks, head movements, hyperextension posturing, chewing, and oroalimentary automatisms, occurred during intracortical electroclinical seizures. MTA was detected in 18 (81.8%) of the 22 patients. There were no statistically significant differences between patients with MTA with and without seizures or status epilepticus. CONCLUSIONS: Most NCSzs in critically ill comatose patients remain undetectable on scalp EEG. SI-NCSzs frequently occur during nursing care, medical procedures, and family visits. Semiology of NCSzs included ictal minor signs and subtle symptoms, such as breathing pattern changes manifested as patient-ventilator dyssynchrony.

Plasma Phosphorylated Tau 231 Increases at One-Year Intervals in Cognitively Unimpaired Subjects.

Background: Plasma biomarkers of Alzheimer's disease (AD) constitute a non-invasive tool for diagnosing and classifying subjects. They change even in preclinical stages, but it is necessary to understand their properties so they can be helpful in a clinical context. Objective: With this work we want to study the evolution of p-tau231 plasma levels in the preclinical stages of AD and its relationship with both cognitive and imaging parameters. Methods: We evaluated plasma phosphorylated (p)-tau231 levels in 146 cognitively unimpaired subjects in sequential visits. We performed a Linear Mixed-effects Model to analyze their rate of change. We also correlated their baseline levels with cognitive tests and structural and functional image values. ATN status was defined based on cerebrospinal fluid biomarkers. Results: Plasma p-tau231 showed a significant rate of change over time. It correlated negatively with memory tests only in amyloid-positive subjects. No significant correlations were found with any imaging measures. Conclusions: Increases in plasma p-tau231 can be detected at one-year intervals in cognitively healthy subjects. It could constitute a sensitive marker for detecting early signs of neuronal network impairment by amyloid.

Neuroradiological findings in GAA-FGF14 ataxia (SCA27B): more than cerebellar atrophy.

Background: GAA-FGF14 ataxia (SCA27B) is a recently reported late-onset ataxia caused by a GAA repeat expansion in intron 1 of the FGF14 gene. Initial studies revealed cerebellar atrophy in 74-97% of patients. A more detailed brain imaging characterization of GAA-FGF14 ataxia is now needed to provide supportive diagnostic features and earlier disease recognition. Methods: We performed a retrospective review of the brain MRIs of 35 patients (median age at MRI 63 years; range 28-88 years) from Quebec (n=27), Nancy (n=3), Perth (n=3) and Bengaluru (n=2) to assess the presence of atrophy in vermis, cerebellar hemispheres, brainstem, cerebral hemispheres, and corpus callosum, as well as white matter involvement. Following the identification of the superior cerebellar peduncles (SCPs) involvement, we verified its presence in 54 GAA-FGF14 ataxia patients from four independent cohorts (Tübingen n=29; Donostia n=12; Innsbruck n=7; Cantabria n=6). To assess lobular atrophy, we performed quantitative cerebellar segmentation in 5 affected subjects with available 3D T1-weighted images and matched controls. Results: Cerebellar atrophy was documented in 33 subjects (94.3%). We observed SCP involvement in 22 subjects (62.8%) and confirmed this finding in 30/54 (55.6%) subjects from the validation cohorts. Cerebellar segmentation showed reduced mean volumes of lobules X and IV in the 5 affected individuals. Conclusions: Cerebellar atrophy is a key feature of GAA-FGF14 ataxia. The frequent SCP involvement observed in different cohorts may facilitate the diagnosis. The predominant involvement of lobule X correlates with the frequently observed downbeat nystagmus.

Outpatient substance abuse treatment completion rates for racial-ethnic minorities during the Great Recession.

There has been minimal research linking the effects on racial-ethnic minorities' health outcomes, particularly research focused on racial-ethnic minorities seeking outpatient substance abuse treatment in the United States. The Great Recession from December 2007 to June 2009 in the United States provides the backdrop against the completion of substance abuse treatments among racial-ethnic minorities that may be associated with the impacts on users' social realities. We utilized data from the 2006-2011 Treatment Episode Datasets-Discharge (TEDS-D) dataset which collects data on outpatient substance abuse treatment institutions throughout the United States. The substance abuse treatment completion rates were higher prior to the Great Recession and lower following the Great Recession. Hispanics were more likely than non-Hispanic whites to complete substance abuse treatment, while other minority groups such as Non-Hispanic Blacks, were less likely to do so. Clients in the Northeast and West regions were more likely to successfully complete substance abuse treatment than those in the South. These findings have implications for impacting outpatient substance abuse treatment completion rates following the Great Recession to reduce racial-ethnic disparities which were impacted by region. Even amid an economic recession, treatment for substance abuse should continue to be a top concern.

Lista de verificación de tomografía computarizada de hueso temporal y base de cráneo lateral / Checklist of the temporal bone and lateral skull base CT- scan

La tomografía computarizada del hueso temporal es una prueba de imagen fundamental para el diagnóstico y tratamiento de diversas entidades que afectan a esta compleja estructura. La tomografía computarizada permite una representación más detallada de las estructuras óseas que la resonancia magnética, lo que determina que sea la prueba de elección para la planificación de la cirugía otológica.El objetivo de este trabajo es el de elaborar una lista de verificación o checklist que permita al otorrinolaringólogo estudiar y valorar de forma sistemática y organizada las principales estructuras de referencia, variantes anatómicas y cambios posquirúrgicos más frecuentes antes de una cirugía segura.Esta revisión ha sido promovida por la Sociedad Española de Otorrinolaringología y redactada en un formato de lista de verificación dividida en las diferentes regiones del hueso temporal y base de cráneo lateral. (AU)

Computed tomography scan of the temporal bone is a fundamental imaging modality for both the diagnosis and treatment of a wide range of pathologies affecting this complex structure. Temporal bone computed tomography scan provides a more detailed depiction of bone structures, compared with magnetic resonance imaging and, for this reason computed tomography scan is the imaging modality of choice in the planning of otological surgery.The aim of this article is to present a checklist to allow the otolaryngologist to assess systematically and in an organized manner the main anatomical landmarks, anatomical variants, as well as the most common postoperative surgical changes, which can be identified before any safe otological surgery.This revision was promoted by the Spanish Society of Otolaryngology and elaborated in a checklist template divided into the different areas of the temporal bone and the lateral skull base. (AU)

Checklist of the temporal bone and lateral skull base CT-scan.

Computed tomography scan of the temporal bone is a fundamental imaging modality for both the diagnosis and treatment of a wide range of pathologies affecting this complex structure. Temporal bone computed tomography scan provides a more detailed depiction of bone structures, compared with magnetic resonance imaging and, for this reason computed tomography scan is the imaging modality of choice in the planning of otological surgery. The aim of this article is to present a checklist to allow the otolaryngologist to assess systematically and in an organized manner the main anatomical landmarks, anatomical variants, as well as the most common postoperative surgical changes, which can be identified before any safe otological surgery. This revision was promoted by the Spanish Society of Otolaryngology and elaborated in a checklist template divided into the different areas of the temporal bone and the lateral skull base.

Dynamic sampling rate: harnessing frame coherence in graphics applications for energy-efficient GPUs.

In real-time rendering, a 3D scene is modelled with meshes of triangles that the GPU projects to the screen. They are discretized by sampling each triangle at regular space intervals to generate fragments which are then added texture and lighting effects by a shader program. Realistic scenes require detailed geometric models, complex shaders, high-resolution displays and high screen refreshing rates, which all come at a great compute time and energy cost. This cost is often dominated by the fragment shader, which runs for each sampled fragment. Conventional GPUs sample the triangles once per pixel; however, there are many screen regions containing low variation that produce identical fragments and could be sampled at lower than pixel-rate with no loss in quality. Additionally, as temporal frame coherence makes consecutive frames very similar, such variations are usually maintained from frame to frame. This work proposes Dynamic Sampling Rate (DSR), a novel hardware mechanism to reduce redundancy and improve the energy efficiency in graphics applications. DSR analyzes the spatial frequencies of the scene once it has been rendered. Then, it leverages the temporal coherence in consecutive frames to decide, for each region of the screen, the lowest sampling rate to employ in the next frame that maintains image quality. We evaluate the performance of a state-of-the-art mobile GPU architecture extended with DSR for a wide variety of applications. Experimental results show that DSR is able to remove most of the redundancy inherent in the color computations at fragment granularity, which brings average speedups of 1.68x and energy savings of 40%.

Typical absence status epilepticus in older people: syndromic delineation.

Objective We describe the clinical, electroencephalograph^ and neuroimaging findings of older patients with typical absence status epilepticus (ASE). Methods This investigation was a retrospective analysis of prospectively collected consecutive patients between January 2011 and October 2021. All patients ≥60 years with impairment of awareness and continuous generalized, rhythmic, synchronous and symmetric epileptiform discharges and normal background on video-electroencephalogram (vEEG) were included. Results Six patients were identified with a diagnosis of typical ASE. The mean age was 67 years. Five could be classified as idiopathic generalized epilepsy (IGE) though two had been erroneously categorized as cryptogenic focal epilepsy (FE). In one, the episode of ASE was thought to represent the beginning of late-onset IGE (de novo late-onset typical ASE). In all cases, ASE was controlled within the first 24 hours. Significance Typical ASE is a rare cause of confusion in the elderly population requiring urgent vEEG evaluation. It most frequently represents reactivation of a previous IGE, in effect related to patients with epilepsy with onset in childhood or adolescence, not previously diagnosed or treated, representing rather the debut of (de novo) late-onset IGE.

A rare case of a secondary pituitary abscess arising in a craniopharyngioma with atypical presentation and clinical course.

Pituitary abscesses are very uncommon. They are divided into primary, arising within a healthy gland, and secondary, observed with an underlying pre-existing lesion. Here we present the eighth case reported of a secondary abscess within a craniopharyngioma. A 59-year-old-woman presented with a 3-week history of headache, and fever. Physical examination was unremarkable. An Magnetic Resonance Imaging (MRI) showed a pituitary lesion suggestive of a chronic inflammatory process. She was diagnosed with lymphocytic meningitis with hypophysitis and she was treated with corticosteroids. Two months later she presented with headache and fever again. Control MRI showed enlargement of the pituitary lesion. Therefore, a transsphenoidal biopsy was performed. During the procedure, purulent material was released. Histological study demonstrated a craniopharyngioma and meningeal inflammation. Empiric antibiotics were started. Three months post-operatively, a follow-up MRI showed a suspect minimal residual mass. Secondary pituitary abscesses are rare. The key to successful management is a high index of suspicion. Transsphenoidal surgical evacuation plus antibiotics is the mainstay of treatment. Although most symptoms resolve, endocrinopathies improve only rarely.

Omega-Test: A Predictive Early-Z Culling to Improve the Graphics Pipeline Energy-Efficiency.

The most common task of GPUs is to render images in real time. When rendering a 3D scene, a key step is to determine which parts of every object are visible in the final image. There are different approaches to solve the visibility problem, the Z-Test being the most common. A main factor that significantly penalizes the energy efficiency of a GPU, especially in the mobile arena, is the so-called overdraw, which happens when a portion of an object is shaded and rendered but finally occluded by another object. This useless work results in a waste of energy; however, a conventional Z-Test only avoids a fraction of it. In this article we present a novel microarchitectural technique, the Omega-Test, to drastically reduce the overdraw on a Tile-Based Rendering (TBR) architecture. Graphics applications have a great degree of inter-frame coherence, which makes the output of a frame very similar to the previous one. The proposed approach leverages the frame-to-frame coherence by using the resulting information of the Z-Test for a tile (a buffer containing all the calculated pixel depths for a tile), which is discarded by nowadays GPUs, to predict the visibility of the same tile in the next frame. As a result, the Omega-Test early identifies occluded parts of the scene and avoids the rendering of non-visible surfaces eliminating costly computations and off-chip memory accesses. Our experimental evaluation shows average EDP savings in the overall GPU/Memory system of 26.4 percent and an average speedup of 16.3 percent for the evaluated benchmarks.

Imaging findings of neurologic complications in lung transplantation: Review of a 9-year cohort.

BACKGROUND: Lung transplantation (LT) requires complex multidisciplinary organization and constitutes a therapeutic option and a life-saving procedure. Although the number of lung recipients continues to increase, neurological complications and death rates following lung transplantation are still higher than desirable. PURPOSE: This study aims to analyse the neuroimaging findings in a cohort of adult patients with LT. MATERIAL AND METHODS: A retrospective cohort study of all lung transplant recipients (344 patients: 205 men and 139 women) at a single institution from January 2011 to January 2020. The collected data included demographic features, clinical data and evaluation of the imaging findings. We also recorded the date of neurological complication(s) and the underlying disease motivating lung transplantation. RESULTS: We found an elevated rate of neuroimaging findings in patients following LT with 32.6% of positive studies. In our cohort, the average time after LT to a neurological complication was 4.9 months post-transplant. Encephalopathy, critical illness polyneuropathy and stroke, in that order, were the most frequent neurological complications. Structural abnormalities in brain imaging were more often detected using MRI than CT for indications of encephalopathy and seizures. CONCLUSIONS: LT recipients constitute an especially vulnerable group that needs close surveillance, mainly during the early post-transplant period.

Intracortical focal non-convulsive status epilepticus causing cerebral hypoxia and intracranial hypertension.

We describe the pathophysiological consequences and long-term neurological outcome of a patient with acute brain injury (ABI) in whom intracortical electroencephalography (iEEG) captured an episode of prolonged focal non-convulsive status epilepticus (NCSE) that remained undetectable on scalp electroencephalography. A 53-year-old right-handed woman was admitted to hospital due to a large frontal left intraparenchymal hematoma. Over two and a half days, we captured recurrent non-convulsive electrographic and electroclinical seizures compatible with the diagnosis of intracortical focal NCSE. The patient remained sedated and a burst-suppression pattern was obtained. We also performed invasive brain multimodality monitoring including iEEG and measurements of intracranial pressure (ICP), partial brain tissue oxygenation (PbtO2) and brain temperature. During non-convulsive electrographic and electroclinical seizures, the values of PbtO2 decreased and those of ICP increased. Six months later, brain MRI revealed encephalomalacia localized to the left paramedial fronto-basal region. The neuropsychological assessment carried out one year after the injury showed scores below average in verbal learning memory, motor dexterity and executive functions. In summary, iEEG is a feasible innovative invasive technique that may be used to record non-convulsive electrographic and electroclinical seizures which remain invisible on the surface. Intracortical focal NCSE causes metabolic changes such as reduced brain oxygenation and an increase in ICP that can further damage previously compromised brain tissue.

Instagram's Influence on Radiology Today: Reviewing the Evolving Educational Journey from a Hospital to National Societies.

We define social media as an interactive online platform that allows users to communicate and exchange knowledge. Educational and medical profiles have slowly emerged on different social media platforms, helping to teach about and publicize diverse aspects of medicine. Radiology is one of the specialties that could potentially benefit the most from social media, as the radiologist tends to have little outside-the-hospital representation. Progressively, audiovisual content has been gaining ground on social networks: Facebook, Twitter, Instagram, Youtube, TikTok, etc. Instagram appears to be ideally suited for radiology given its image-based nature. In addition, Instagram can also be used as a tool to help radiologists share and discuss radiological images, improve communication with clinicians and patients, advertise themselves and their specialty, and humanize their profession. Nevertheless, legal matters and privacy issues should always be taken into account when using these tools. In this overview, we describe the development of social networks and communication tools in our own radiology department, focusing especially on our Instagram account, as it has had a wide impact on our hospital and radiology residents around the country. We will also provide a summary of the various social media platforms used for radiology education along with their pros and cons, including useful tips for safe and efficient use.

Invisible compression, anterior fossa tumor causing trigeminal neuralgia.

BACKGROUND: Trigeminal neuralgia secondary to posterior and middle fossae tumors, whether ipsilateral or contralateral, has been well described. However, this disabling disease has never been reported in the context of anterior fossa neoplasms. CASE DESCRIPTION: A 75-year-old female with right hemifacial pain was diagnosed with an anterior clinoid meningioma. Despite neuroimaging did not show any apparent anatomical or neurovascular conflict, a detailed MRI analysis revealed a V3 hyperintensity. Not only symptoms completely resolved after surgical resection but also this radiological sign disappeared. Nowadays, the patient remains asymptomatic and V3 hyperintensity has not reappeared during her follow-up. CONCLUSION: A surgical definitive treatment can be offered to patients suffering from trigeminal neuralgia secondary to lesions adjacent to Gasserian ganglion or trigeminal branches. In this respect, posterior and middle fossae tumors are well-reported etiologies. Nevertheless, in the absence of evident compression, other neoplasms located in the vicinity of these critical structures and considered as radiological findings may be involved in trigeminal pain. Microvascular and pressure gradient changes could be an underlying cause of these symptoms in anterior skull base lesions. Here, we report the case of a patient with uncontrollable hemifacial pain resolved after anterior clinoid meningioma removal.

A rare case of a secondary pituitary abscess arising in a craniopharyngioma with atypical presentation and clinical course.

Pituitary abscesses are very uncommon. They are divided into primary, arising within a healthy gland, and secondary, observed with an underlying pre-existing lesion. Here we present the eighth case reported of a secondary abscess within a craniopharyngioma. A 59-year-old-woman presented with a 3-week history of headache, and fever. Physical examination was unremarkable. An Magnetic Resonance Imaging (MRI) showed a pituitary lesion suggestive of a chronic inflammatory process. She was diagnosed with lymphocytic meningitis with hypophysitis and she was treated with corticosteroids. Two months later she presented with headache and fever again. Control MRI showed enlargement of the pituitary lesion. Therefore, a transsphenoidal biopsy was performed. During the procedure, purulent material was released. Histological study demonstrated a craniopharyngioma and meningeal inflammation. Empiric antibiotics were started. Three months post-operatively, a follow-up MRI showed a suspect minimal residual mass. Secondary pituitary abscesses are rare. The key to successful management is a high index of suspicion. Transsphenoidal surgical evacuation plus antibiotics is the mainstay of treatment. Although most symptoms resolve, endocrinopathies improve only rarely.

Predicting the Extent of Resection in Low-Grade Glioma by Using Intratumoral Tractography to Detect Eloquent Fascicles Within the Tumor.

BACKGROUND: An early maximal safe surgical resection is the current treatment paradigm for low-grade glioma (LGG). Nevertheless, there are no reliable methods to accurately predict the axonal intratumoral eloquent areas and, consequently, to predict the extent of resection. OBJECTIVE: To describe the functional predictive value of eloquent white matter tracts within the tumor by using a pre- and postoperative intratumoral diffusion tensor imaging (DTI) tractography protocol in patients with LGG. METHODS: A preoperative intratumoral DTI-based tractography protocol, using the tumor segmented volume as the only seed region, was used to assess the tracts within the tumor boundaries in 22 consecutive patients with LGG. The reconstructed tracts were correlated with intraoperative electrical stimulation (IES)-based language and motor subcortical mapping findings and the extent of resection was assessed by tumor volumetrics. RESULTS: Identification of intratumoral language and motor tracts significantly predicted eloquent areas within the tumor during the IES mapping: the positive predictive value for the pyramidal tract, the inferior fronto-occipital fasciculus, the arcuate fasciculus and the inferior longitudinal fasciculus positive was 100%, 100%, 33%, and 80%, respectively, whereas negative predictive value was 100% for all of them. The reconstruction of at least one of these tracts within the tumor was significantly associated with a lower extent of resection (67%) as opposed to the extent of resection in the cases with a negative intratumoral tractography (100%) (P < .0001). CONCLUSION: Intratumoral DTI-based tractography is a simple and reliable method, useful in assessing glioma resectability based on the analysis of intratumoral eloquent areas associated with motor and language tracts within the tumor.

Epidermoid Cyst Extending Along Trigeminal Nerve Pathway with Unusual Imaging Findings.

Epidermoid cysts (ECs) are benign extraaxial tumors. They frequently occur at the cerebellopontine angle and parasellar regions. However, they rarely occur in the Meckel's cave. Typically, ECs appear as a hypointense mass on T1-weighted magnetic resonance imaging (MRI) and hyperintense on T2-weighted MRI. However, ECs may occasionally present as hyperintense on T1-weighted imaging and hypointense on T2-weighted imaging. When this occurs, they are known as white epidermoid cysts. We present a case of a 25-year-old woman with a 3-month history of hypoesthesia in the distribution of the right trigeminal nerve. MRI showed a lesion located within the Meckel's cave. The MRI signal was heterogeneous, with hyperintense areas on T1-weighted images, being hypointense on T2-weighted imaging. Preoperative suspicion was trigeminal schwannoma with unusual radiologic features. Finally, the pathologic diagnosis was epidermoid cyst. Therefore to establish a proper preoperative diagnosis, one should be aware that ECs can occur in Meckel's cave and with unusual radiologic features, as occurred in the case described earlier.

Lingual epilepsia partialis continua: a detailed video-EEG and neuroimaging study.

Motor epilepsia partialis continua (EPC) is a frequent and widely described variant of simple focal motor status epilepticus. However, lingual EPC is an unusual epileptic condition. We present a case of lingual EPC secondary to low-grade glioma in which the EEG and neuroimaging features were particularly remarkable. The video-EEG showed lateralized periodic discharges with superimposed rhythmic activity and frequent recurrent focal epileptic seizures. Moreover, brain magnetic resonance imaging showed a right temporo-insular cortico-subcortical lesion which was hyperintense on FLAIR, suggestive of low-grade glioma. In addition, diffusion-weighted imaging and arterial spin labelling series showed restricted diffusion in the right temporo-insular and parietal cortex and increased cerebral flow, respectively. All these findings are in keeping with changes related to persistent focal status epilepticus. Finally, we review the literature and discuss the differential diagnosis of this rare epileptic entity. [Published with video sequence].

Brain grey matter abnormalities in first episode non-affective psychosis patients with suicidal behaviours: The role of neurocognitive functioning.

BACKGROUND: Suicide is one of the leading causes of premature death in first-episode psychosis (FEP) patients. The understanding of suicidal behaviour (SB) is limited, and new and integrative approaches focusing on the likely relationship of the biological and cognitive features of SB in the early phases of psychosis are warranted. We aimed to study the relationship of brain grey matter anomalies and cognitive functioning with SB or suicidal risk in a large sample of non-affective FEP patients. METHODS: We used a voxel-based morphometry analysis in 145 FEP patients to investigate the pattern of structural brain abnormalities related to SB. In addition, bivariate and multivariate analyses were performed to explore the relationship between cognitive functioning and SB. RESULTS: A reduction in grey matter volume in the frontal area, temporal gyrus, precuneus, uncus, amygdala, left cuneus and subcallosal gyrus as well as a marked regional volume reduction in the right hemisphere was linked with the presence of SB. Additionally, worse global cognitive functioning and living in urban areas were identified as suicide risk factors. CONCLUSIONS: This study provides some insights about the brain abnormalities associated with SB in FEP patients. Specifically, the areas reported are involved in important functions related to SB, such as impulsivity, problem solving or responses to pain. Thus, the results confirm the relevant role of cognitive functioning on SB.