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Simple Summary: Intracranial Epidermoid Cysts (IECs) are rare tumors. Despite their benign course, IECs can adhere to critical brain structures resulting in impairment and morbidity. The primary treatment is surgery; however, cyst adherence often complicates complete removal, resulting in notably high progression rates after subtotal resection. Due to the rarity of IECs, there has been limited research focused on understanding the mechanisms of the disease and advancing therapeutic options. As a result, there are currently no effective drug therapies available for treating patients with IECs. Targeted therapy is an effective form of treatment for tumors. It focuses on mutations that turn healthy cells into tumor cells. The mutation profile of IECs has not been investigated. We aimed to investigate the somatic landscape of IECs to gain insights into tumor biology and identify mutations that could potentially serve as targets for additional therapies. Surgery is still the most effective treatment for these patients. Background/Objectives: Intracranial Epidermoid Cysts (IECs) are rare intracranial tumors primarily treated through surgery. Cyst adherence complicates complete removal, leading to high rates of tumor progression after subtotal resection. The molecular drivers of IEC remain unknown. Consequently, advances in treatment have fallen short. Tumor genetic profiling has revealed potential targets for drug development, including FDA-approved options and reshaping treatment. The genetic landscape of IECs has not been explored. We applied Whole Exome Sequencing (WES) to IECs to gain insights into the mechanisms of oncogenesis and identify potential therapeutic targets. Methods: We performed WES on tumor tissue and matched blood samples, when available. Following GATK best practices, we conducted read processing, quality control, somatic variant calling, and copy-number inference. Data analyses and visualization were conducted in R. Results: Top altered genes are associated with the immune system and tumor microenvironment, suggesting a mechanism of immune evasion. Gene and pathway enrichment revealed a high mutation burden in genes associated with Extracellular Matrix (ECM) and PI3K-AKT-mTOR cascades. Recurrent and deleterious alterations in NOTCH2 and USP8 were identified in 50% and 30% of the cohort, respectively. Frequent amplifications in deubiquitinases and beta-defensins strengthened the involvement of immune mechanisms for oncogenic transformation. Conclusions: Top altered genes and recurrent mutations may play a role in shaping the microenvironment and modulating immune evasion in IECs. USP8 and NOTCH2 may serve as clinically relevant target for IECs. Finally, we present evidence that the crosstalk between the PI3K-Akt-mTOR and ECM signaling pathways may play a role in modulating the immune escape mechanism in IECs. [ABSTRACT FROM AUTHOR]

Background: The oral microbiota is the second largest microbial community in humans. It contributes considerably to microbial diversity and health effects, much like the gut microbiota. Despite physical and chemical barriers separating the oral cavity from the gastrointestinal tract, bidirectional microbial transmission occurs between the two regions, influencing overall host health. Method: This review explores the intricate interplay of the oral–gut–brain axis, highlighting the pivotal role of the oral microbiota in systemic health and ageing, and how it can be influenced by diet. Results: Recent research suggests a relationship between oral diseases, such as periodontitis, and gastrointestinal problems, highlighting the broader significance of the oral–gut axis in systemic diseases, as well as the oral–gut–brain axis in neurological disorders and mental health. Diet influences microbial diversity in the oral cavity and the gut. While certain diets/dietary components improve both gut and oral health, others, such as fermentable carbohydrates, can promote oral pathogens while boosting gut health. Conclusions: Understanding these dynamics is key for promoting a healthy oral–gut–brain axis through dietary interventions that support microbial diversity and mitigate age-related health risks. [ABSTRACT FROM AUTHOR]

Central nervous system (CNS) involvement in autoimmune rheumatic diseases represents a significant challenge for clinicians across all specialties. While most reviews on the subject focus on neurological manifestations within a specific rheumatic disease, few descriptions shift from neurological clinical syndromes to achieve rheumatological diagnoses. This narrative review aims to synthesize current knowledge on the diagnosis and management of CNS manifestations occurring in the most prevalent rheumatic conditions in adults. We searched the MEDLINE database using the terms "central nervous system", "rheumatic diseases", "systemic lupus erythematosus", "rheumatoid arthritis", "Sjögren syndrome", and "vasculitis". The search strategy included review articles from 2019 to 2024, published in English, Spanish, or Portuguese. We explored the pathophysiological mechanisms linking autoimmunity to CNS pathology, emphasizing the role of syndromic reasoning, autoantibody profiles, and imaging modalities as tools for diagnosis and determination of inflammatory activity. The review also discusses differential diagnoses through a stepwise approach to neurological syndromes, summarized in diagnostic flowcharts, and presents updated treatment options. Although our approach is primarily semiology-based, the complexity of the subject invites future endeavors involving new technologies, such as functional MRI, MR spectroscopy, and nuclear medicine. [ABSTRACT FROM AUTHOR]

This study aims to assess the diagnostic accuracy of non-contrast-enhanced 4D MR angiography (NCE-4D-MRA) compared to contrast-enhanced 4D MR angiography (CE-4D-MRA) for the detection and angioarchitectural characterisation of brain arteriovenous malformations (bAVMs). Utilising a retrospective design, we examined 54 MRA pairs from 43 patients with bAVMs, using digital subtraction angiography (DSA) as the reference standard. Both NCE-4D-MRA and CE-4D-MRA were performed using a 3-T MR imaging system. The primary objectives were to evaluate the diagnostic performance of NCE-4D-MRA against CE-4D-MRA and DSA and to assess concordance between imaging modalities in grading bAVMs according to four main scales: Spetzler–Martin, Buffalo, AVM embocure score (AVMES), and R2eDAVM. Our results demonstrated that NCE-4D-MRA had a higher accuracy and specificity compared to CE-4D-MRA (0.85 vs. 0.83 and 95% vs. 85%, respectively) and similar agreement, with DSA detecting shunts in bAVMs or residuals. Concordance in grading bAVMs was substantial between NCE-4D-MRA and DSA, particularly for the Spetzler–Martin and Buffalo scales, with CE-4D-MRA showing slightly higher kappa values for interobserver agreement. The study highlights the potential of NCE-4D-MRA as a diagnostic tool for bAVMs, offering comparable accuracy to CE-4D-MRA while avoiding the risks associated with gadolinium-based contrast agents. The safety profile of imaging techniques is a significant concern in the long-term follow up of bAVMs, and further prospective research should focus on NCE-4D-MRA protocol improvement for clinical use. [ABSTRACT FROM AUTHOR]

Ischemic stroke is a leading cause of disability worldwide. While much of post-stroke recovery is focused on physical rehabilitation, post-stroke dementia (PSD) is also a significant contributor to poor functional outcomes. Predictive tools to identify stroke survivors at risk for the development of PSD are limited to brief screening cognitive tests. Emerging biochemical, genetic, and neuroimaging biomarkers are being investigated in an effort to unveil better indicators of PSD. Additionally, acetylcholinesterase inhibitors, NMDA receptor antagonists, dopamine receptor agonists, antidepressants, and cognitive rehabilitation are current therapeutic options for PSD. Focusing on the chronic sequelae of stroke that impair neuroplasticity highlights the need for continued investigative trials to better assess functional outcomes in treatments targeted for PSD. [ABSTRACT FROM AUTHOR]

One's own voice undergoes unique processing that distinguishes it from others' voices, and thus listening to it may have a special neural basis for self-talk as an emotion regulation strategy. This study aimed to elucidate how neural effects of one's own voice differ from those of others' voices on the implementation of emotion regulation strategies. Twenty-one healthy adults were scanned using fMRI while listening to sentences synthesized in their own or others' voices for self-affirmation and cognitive defusion, which were based on mental commitments to strengthen one's positive aspects and imagining metaphoric actions to shake off negative aspects, respectively. The interaction effect between voice identity and strategy was observed in the superior temporal sulcus, middle temporal gyrus, and parahippocampal cortex, and activity in these regions showed that the uniqueness of one's own voice is reflected more strongly for cognitive defusion than for self-affirmation. This interaction was also seen in the precuneus, suggesting intertwining of self-referential processing and episodic memory retrieval in self-affirmation with one's own voice. These results imply that unique effects of one's own voice may be expressed differently due to the degree of engagement of neural sharpening-related regions and self-referential networks depending on the type of emotion regulation. [ABSTRACT FROM AUTHOR]

Ultra-high contrast (UHC) MRI describes forms of MRI in which little or no contrast is seen on conventional MRI images but very high contrast is seen with UHC techniques. One of these techniques uses the divided subtracted inversion recovery (dSIR) sequence, which, in modelling studies, can produce ten times the contrast of conventional inversion recovery (IR) sequences. When used in cases of mild traumatic brain injury (mTBI), the dSIR sequence frequently shows extensive abnormalities in white matter that appears normal when imaged with conventional T2-fluid-attenuated IR (T2-FLAIR) sequences. The changes are bilateral and symmetrical in white matter of the cerebral and cerebellar hemispheres. They partially spare the anterior and posterior central corpus callosum and peripheral white matter of the cerebral hemispheres and are described as the whiteout sign. In addition to mTBI, the whiteout sign has also been seen in methamphetamine use disorder and Grinker's myelinopathy (delayed post-hypoxic leukoencephalopathy) in the absence of abnormalities on T2-FLAIR images, and is a central component of post-insult leukoencephalopathy syndromes. This paper describes the concept of ultra-high contrast MRI, the whiteout sign, the theory underlying the use of dSIR sequences and post-insult leukoencephalopathy syndromes. [ABSTRACT FROM AUTHOR]

Purpose of Review: This review aims to provide a comprehensive overview of the diagnosis of brain death/death by neurologic criteria (BD/DNC) by emphasizing the clinical criteria established by the American Academy of Neurology (AAN) in light of their updated guidelines released in 2023. In this review, we will focus on the current implementation of ancillary tests including the catheter cerebral angiogram, nuclear scintigraphy, and transcranial Doppler, which provide support in diagnoses when clinical examination and apnea tests are inconclusive. Finally, we will also provide examples to discuss the implementation of certain imaging studies in the context of diagnosing BD/DNC. Recent Findings: Recent developments in the field of neurology have emphasized the importance of clinical criteria for diagnosing BD/DNC, with the AAN providing clear updated guidelines that include coma, apnea, and the absence of brainstem reflexes. Current ancillary tests, including the catheter cerebral angiogram, nuclear scintigraphy, and transcranial Doppler play a crucial role in confirming BD/DNC when the clinical assessment is limited. The role of commonly used imaging studies including computed tomography and magnetic resonance angiographies of the brain as well as CT/MR perfusion studies will also be discussed in the context of these new guidelines. Summary: BD/DNC represents the permanent cessation of brain functions, including the brainstem. This review article provides the historical context, clinical criteria, and pathophysiology that goes into making this diagnosis. Additionally, it explores the various ancillary tests and selected imaging studies that are currently used to diagnose BD/DNC under the newly updated AAN guidelines. Understanding the evolution of how to effectively use these diagnostic tools is crucial for healthcare professionals who encounter these BD/DNC cases in their practice. [ABSTRACT FROM AUTHOR]

Mammogram exam images are useful in identifying diseases, such as breast cancer, which is one of the deadliest cancers, affecting adult women around the world. Computational image analysis and machine learning techniques can help experts identify abnormalities in these images. In this work we present a new system to help diagnose and analyze breast mammogram images. To do this, the system a method the Selection of the Most Discriminant Attributes of the images preprocessed by BEMD "SMDA-BEMD", this entails picking the most pertinent traits from the collection of variables that characterize the state under study. A reduction of attribute based on a transformation of the data also called an extraction of characteristics by extracting the Haralick attributes from the Co-occurrence Matrices Methods "GLCM" this reduction which consists of replacing the initial set of data by a new reduced set, constructed at from the initial set of features extracted by images decomposed using Bidimensional Empirical Multimodal Decomposition "BEMD", for discrimination of breast mammogram images (healthy and pathology) using BEMD. This decomposition makes it possible to decompose an image into several Bidimensional Intrinsic Mode Functions "BIMFs" modes and a residue. The results obtained show that mammographic images can be represented in a relatively short space by selecting the most discriminating features based on a supervised method where they can be differentiated with high reliability between healthy mammographic images and pathologies, However, certain aspects and findings demonstrate how successful the suggested strategy is to detect the tumor. A BEMD technique is used as preprocessing on mammographic images. This suggested methodology makes it possible to obtain consistent results and establishes the discrimination threshold for mammography images (healthy and pathological), the classification rate is improved (98.6%) compared to existing cutting-edge techniques in the field. This approach is tested and validated on mammographic medical images from the Kenitra-Morocco reproductive health reference center (CRSRKM) which contains breast mammographic images of normal and pathological cases. [ABSTRACT FROM AUTHOR]

Dissecting aneurysms in patients with spontaneous cervical artery dissections have, so far, been reported as "benign", but more specific information is scarce. We aimed to elucidate (1) vascular risk factors, (2) local and ischemic symptoms, and (3) long-term prognosis compared to non-aneurysmal dissections. This case–control study included consecutive patients with spontaneous cervical artery dissection from three university hospitals in Switzerland and France, evaluated at baseline and at 3 months. In addition, further follow-ups were performed at the discretion of the treating physician. Dissecting aneurysms were diagnosed with duplex sonography, magnetic resonance angiography, and/or digital subtraction angiography. Of 1012 patients, 151 (14.9%) presented with 167 dissecting aneurysms at baseline (n = 103) or follow-up (n = 64). The median follow-up was 24.9 months (IQR: 6.8–60.8). Compared to patients without a dissecting aneurysm there were no significant differences in the vascular risk factors or local symptoms (91.4 vs. 89.8%). Ischemic strokes at baseline were less common (29.1% vs. 54.4%; OR: 0.41; 95% CI: 0.28–0.60) in patients with a dissecting aneurysm, even after correction for the degree of stenosis of the dissected arteries (OR: 0.53; 95% CI: 0.34–0.81). Patients with a dissecting aneurysm more often had a favorable clinical outcome (modified Rankin Scale Score of 0–1) at 3 months (80.6% vs. 54.5%). There was no significant difference in recurrent cerebrovascular events at 3 months or overall. The lower rate of ischemic strokes at baseline may reflect a different pathogenic mechanism, such as a smaller initial tear in the vessel wall or an increased vessel caliber from an early or primary intramural hematoma with a different shape. [ABSTRACT FROM AUTHOR]

Divided and subtracted MRI is a novel imaging processing technique, where the difference of two images is divided by their sum. When the sequence parameters are chosen properly, this results in images with a high T1 or T2 weighting over a small range of tissues with specific T1 and T2 values. In the T1 domain, we describe the implementation of the divided Subtracted Inversion Recovery Sequence (dSIR), which is used to image very small changes in T1 from normal in white matter. dSIR has shown widespread changes in otherwise normal-appearing white matter in patients suffering from mild traumatic brain injury (mTBI), substance abuse, and ischemic leukoencephalopathy. It can also be targeted to measure small changes in T1 from normal in other tissues. In the T2 domain, we describe the divided echo subtraction (dES) sequence that is used to image musculoskeletal tissues with a very short T2*. These tissues include fascia, tendons, and aponeuroses. In this manuscript, we explain how this contrast is generated, review how these techniques are used in our research, and discuss the current challenges and limitations of this technique. [ABSTRACT FROM AUTHOR]

Arterial spin labeling (ASL) has emerged as a promising noninvasive tool for the evaluation of both pediatric and adult arteriovenous malformations (AVMs). This paper reviews the advantages and challenges associated with the use of ASL in AVM assessment. An assessment of the diagnostic workup of AVMs and their variants in both adult and pediatric populations is proposed. Evaluation after treatments, whether endovascular or microsurgical, was similarly examined. ASL, with its endogenous tracer and favorable safety profile, offers functional assessment and arterial feeder identification. ASL has demonstrated strong performance in identifying feeder arteries and detecting arteriovenous shunting, although some studies report inferior performance compared with digital subtraction angiography (DSA) in delineating venous drainage. Challenges include uncertainties in sensitivity for specific AVM features. Detecting AVMs in challenging locations, such as the apical cranial convexity, is further complicated, demanding careful consideration due to the risk of underestimating total blood flow. Navigating these challenges, ASL provides a noninvasive avenue with undeniable merits, but a balanced approach considering its limitations is crucial. Larger-scale prospective studies are needed to comprehensively evaluate the diagnostic performance of ASL in AVM assessment. [ABSTRACT FROM AUTHOR]

Due to the occlusion of the anterior choroidal artery (AChA), ischemic strokes are described with the classic clinical triad, namely hemiplegia, hemianesthesia, and homonymous hemianopsia. The aim of this study is to document the characteristic clinical presentation and course of AChA infract cases. We describe five cases with acute infarction in the distribution of the AChA, admitted to the Neurological Department of the University General Hospital of Larissa. Results: All cases presented with hemiparesis and lower facial nerve palsy, while four of them had dysarthria, and two patients exhibited ataxia. Two cases underwent intravenous thrombolysis. A notable feature was the worsening of the clinical course, specifically the exacerbation of upper limb weakness within 48 h. Stabilization occurred after the third day, with the final development of a more severe clinical presentation than the initial one. Additionally, muscle weakness was more severe in the upper limb than in the lower limb. The recovery of upper limb function was poor in the three-month follow-up for the four cases. While vascular brain episodes are characterized by sudden onset, in AChA infraction, the clinical onset can be gradually developed over a few days, with a greater burden on the upper limb and poorer recovery. [ABSTRACT FROM AUTHOR]

Background: The hyperdense artery sign (HAS) in acute ischemic stroke (AIS) is considered an important marker of a thrombus on computed tomography (CT). An advantage of scanning with dual-energy CT (DECT) is its ability to reconstruct CT images with various energies using the virtual monochromatic imaging (VMI) technique. The aim of this study was to investigate the optimal combination of X-ray energy and slice thickness to detect HASs on DECT. Methods: A total of 32 patients with confirmed occlusion of the horizontal (M1) portion of the middle cerebral artery were included in this study. Modified contrast-to-noise ratio (modified CNR) analysis was used as a method for evaluating HASs in AIS. A region of interest (ROI) was set as an HAS, the M1 portion, and an approximately 2 cm diameter ROI was set as the background including the HAS and measured. CT images with X-ray energies from 40 to 190 keV, with increments of 10 keV, were reconstructed based on VMI with 1, 2, and 3 mm slice thicknesses. Results: The top five combinations of X-ray energy and slice thickness in descending order of the mean HAS-modified CNR were as follows: Rank 1, 60 keV-1 mm; Rank 2, 70 keV-1 mm; Rank 3, 60 keV-2 mm; Rank 4, 80 keV-2 mm; Rank 5, 60 keV-3 mm. Conclusions: Our study showed that the optimal combination to detect an HAS was 60 keV and a 1 mm slice thickness on DECT. [ABSTRACT FROM AUTHOR]

The analysis of cerebrospinal fluid (CSF) remains a valuable diagnostic tool in the evaluation of inflammatory and infectious conditions involving the brain, spinal cord, and meninges. Since many rheumatic inflammatory diseases can involve the central and peripheral nervous system, the aims of this narrative review were to summarize the latest evidence on the use of CSF analysis in the field of neuropsychiatric manifestations of rheumatic diseases. Routine CSF parameters were taken into consideration for this review: appearance; total protein and cellular content (pleocytosis); lactate and/or glucose; CSF/serum albumin quotient; intrathecal synthesis of IgG. Data regarding the role of CSF analysis in the clinical management of neuropsychiatric systemic lupus erythematosus, primary Sjogren's syndrome, rheumatoid arthritis, and Behçet's syndrome are presented. Although no disease-specific picture has been identified, CSF analysis remains a useful diagnostic tool to confirm the presence of a neuro-inflammatory state or, conversely, to exclude the concomitant presence of other inflammatory/infectious diseases affecting the CNS in the context of systemic rheumatologic conditions. [ABSTRACT FROM AUTHOR]

(1) Background: Spinocerebellar ataxias (SCA) is a term that refers to a group of hereditary ataxias, which are neurological diseases characterized by degeneration of the cells that constitute the cerebellum. Studies suggest that magnetic resonance imaging (MRI) supports diagnoses of ataxias, and linear measurements of the aneteroposterior diameter of the midbrain (ADM) have been investigated using MRI. These measurements correspond to studies in spinocerebellar ataxia type 2 (SCA2) patients and in healthy subjects. Our goal was to obtain the cut-off value for ADM atrophy in SCA2 patients. (2) Methods: This study evaluated 99 participants (66 SCA2 patients and 33 healthy controls). The sample was divided into estimations (80%) and validation (20%) samples. Using the estimation sample, we fitted a logistic model using the ADM and obtained the cut-off value through the inverse of regression. (3) Results: The optimal cut-off value of ADM was found to be 18.21 mm. The area under the curve (AUC) of the atrophy risk score was 0.957 (95% CI: 0.895–0.991). Using this cut-off on the validation sample, we found a sensitivity of 100.00% (95% CI: 76.84%–100.00%) and a specificity of 85.71% (95% CI: 42.13%–99.64%). (4) Conclusions: We obtained a cut-off value that has an excellent discriminatory capacity to identify SCA2 patients. [ABSTRACT FROM AUTHOR]

Notch signaling is conserved in C. elegans, Drosophila, and mammals. Among the four NOTCH genes in humans, NOTCH1, NOTCH2, and NOTCH3 are known to cause monogenic hereditary disorders. Most NOTCH-related disorders are congenital and caused by a gain or loss of Notch signaling activity. In contrast, cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) caused by NOTCH3 is adult-onset and considered to be caused by accumulation of the mutant NOTCH3 extracellular domain (N3ECD) and, possibly, by an impairment in Notch signaling. Pathophysiological processes following mutant N3ECD accumulation have been intensively investigated; however, the process leading to N3ECD accumulation and its association with canonical NOTCH3 signaling remain unknown. We reviewed the progress in clarifying the pathophysiological process involving mutant NOTCH3. [ABSTRACT FROM AUTHOR]

A flow diverter (FD) is an effective method for treating wide-necked intracranial aneurysms by inducing hemodynamic changes in aneurysms. However, the procedural technique remains challenging, and it is often not performed properly in many cases of deployment or placements. In this study, three types of FDs that changed the material of the wire were prepared within the same structure. Differences in physical properties, such as before and after delivery loading stent size, radial force, and radiopacity, were evaluated. The performances in terms of deployment and trackability force were also evaluated in a simulated model using these FDs. Furthermore, changes of deployment patterns when these FDs were applied to a 3D-printed aneurysm model were determined. The NiTi FD using only nitinol (NiTi) wire showed 100% size recovery and 42% to 45% metal coverage after loading. The low trackability force (10.9 to 22.9 gf) allows smooth movement within the delivery system. However, NiTi FD cannot be used in actual surgeries due to difficulties in X-ray identification. NiTi-Pt/W FD, a combination of NiTi wire and platinum/tungsten (Pt/W) wire, had the highest radiopacity and compression force (6.03 ± 0.29 gf) among the three FDs. However, it suffered from high trackability force (22.4 to 39.9 gf) and the end part braiding mesh tended to loosen easily, so the procedure became more challenging. The NiTi(Pt) FD using a platinum core nitinol (NiTi(Pt)) wire had similar trackability force (11.3 to 22.1 gf) to NiTi FD and uniform deployment, enhancing procedural convenience. However, concerns about low expansion force (1.79 ± 0.30 gf) and the potential for migration remained. This comparative analysis contributes to a comprehensive understanding of how different wire materials influence the performance of FDs. While this study is still in its early stages and requires further research, its development has the potential to guide clinicians and researchers in optimizing the selection and development of FDs for the effective treatment of intracranial aneurysms. [ABSTRACT FROM AUTHOR]