1,720,988 research outputs found
Neuroradiology training in EU: international survey of 31 countries within UEMS frame
Objective: To assess the current framework of interventional and diagnostic neuroradiology in Europe
Methods: The UEMS (European Union of Medical Specialists) Section of Radiology and the subspecialty UEMS Division
of Neuroradiology collected by e-mail a survey on the situation of diagnostic and Interventional Neuroradiology’
training and practice in Europe. The questionnaire was sent to the national delegates from 31 UEMS member
countries, belonging to the European Union, the European Economic Area and the Council of Europe. In case of
uncertain or discordant replies, the survey envisaged the involvement of neuroradiology scientific societies’ experts for
providing a decisive answer.
Results: A formal post-residency training in diagnostic and interventional neuroradiology is provided respectively
by 12/31 and 20/31 of the European countries. Currently, for becoming neuroradiologist in a country without
fellowship program, a radiologist should (1) get subspecialty credits, (2) follow training inside national or
international neuroradiology departments, or (3) perform the main reporting activity in neuroradiology.
In nearly 2/3 of the States included in the survey, the neurointerventional procedures are provided by radiologists
(22/31) and in the most frequent scenario a specific training in neurovascular is required to all radiologist or nonradiologist
candidates (18/31).
Conclusions: The European framework of neuroradiology’s training and practice that emerged through this
survey is fragmented, but there is an increasing attention by European scientific societies and institutions to
create a common path of training and practice that can guarantee high educational and patient care standards
Demystifying the role of magnetic resonance in identifying intraocular foreign bodies: a case of ocular siderosis
Background: Ocular siderosis (OS) is a significant cause of visual loss due to retained ferrous intraocular foreign bodies (IOFB). Despite its rarity, OS can lead to severe visual impairment if not promptly diagnosed and treated. This case is notable due to the occult nature of the IOFB, which was undetected by standard imaging modalities, emphasizing the critical role of magnetic resonance imaging (MRI) in such scenarios. Case presentation: A 51-year-old Caucasian male presented with progressive vision loss in his right eye over 20 days. Best corrected visual acuity (BCVA) was 20/1000 in the right eye and 20/20 in the left eye. Intraocular pressure (IOP) was 9 mmHg in both eyes. Slit-lamp examination revealed a small linear corneal wound and an iris defect in the right eye, along with a cataract featuring brownish deposits on the anterior capsule. The left eye was normal. Fundus examination of the right eye was hindered by media opacities. Ultrasonography showed a flat retina and choroid with no detectable IOFB. Despite a strong clinical suspicion of OS, computed tomography (CT) did not detect any IOFB. MRI subsequently identified an artifact in the inferior sectors of the right eye, indicative of a metallic IOFB. Surgical intervention involved a 23-gauge vitrectomy, phacoemulsification, IOFB removal and silicon oil (SO) tamponade resulting in a fully restored VA of 20/20 and normal IOP one month post-operation. SO was removed 2 months later. The retina remained adherent with no PVR development, and optical coherence tomography (OCT) scans showed a normal macula. Conclusions: This case underscores the importance of considering OS in patients with unexplained vision loss and history of ocular trauma, even when initial imaging fails to detect an IOFB. MRI proved crucial in identifying the IOFB, highlighting its value in the diagnostic process. Early detection and surgical removal of IOFBs are essential to prevent irreversible visual damage. This case demonstrates that MRI should be employed when CT and ultrasonography are inconclusive, ensuring accurate diagnosis and timely intervention to preserve vision
Weakly Supervised Segmentation Improves the Estimate of the Choroid Plexus Volume: Application to Multiple Sclerosis
The Choroid Plexus (ChP) is a brain vascular tissue responsible for regulatory processes. Modifications in ChP Volume (ChPV) have been associated with neurodegenerative disorders, making ChPV a potential biomarker for monitoring disease progression and severity. The current gold-standard technique to quantify ChPV is manual segmentation on T1-weighted Magnetic Resonance Images. However, this method is time-consuming and prone to variability between different operators. Recently, deep learning methods have emerged as state-of-the-art systems for Magnetic Resonance image segmentation. In this study, we demonstrate that deep learning models can be effectively trained using weakly labeled data, specifically bounding box annotations that lack precise contour information. To explore this concept, we trained a series of models using various strategies that leverage bounding box annotations for segmentation tasks. A model trained on a dataset with manual segmentation masks achieved a lower performance compared with the same model trained with a weakly supervised strategy based on bounding box images. While acknowledging that the increase may not be substantial, it is essential to take into account our limited number of images. This limitation becomes intriguing when considering that compiling extensive datasets is considerably easier using rough ROIs rather than finely segmented ones
Diffusion MRI and silver standard masks to improve CNN-based thalamus segmentation
thalamus segmentatio
Making Visible the Invisible: Automatically Measured Global and Regional Brain Volume Is Associated with Cognitive Impairment and Fatigue in Multiple Sclerosis
In multiple sclerosis (MS), the transition from relapsing-remitting to the secondary-progressive phase is characterized by a progression independent of relapse activity (PIRA), resulting in physical disability accumulation and invisible symptoms, i.e., fatigue and cognitive impairment (CI). These symptoms are related to neurodegenerative processes and have been correlated with MRI measures of brain atrophy only at a group level; however, the application in clinical practice of atrophy-based measurements for single-patient evaluation is yet to be fully investigated. In the present study, we aimed to evaluate the association between brain atrophy, measured with easy-to-use automatic software, and the “invisible” MS symptoms of cognition and fatigue. A total of 69 MS patients were included in the study; cognitive impairment and fatigue (FSS) (in addition to neurological disability, EDSS) were assessed and correlated with brain volumes calculated using the automated software QyScore® which is validated for single-patient use in the clinical setting. Results showed that the cognitive status was accurately reflected by measures of atrophy, with a sensitivity of up to 90%. CI patients showed a lower volume compared to cognitively normal patients in the whole brain (p = 0.017), gray matter (p = 0.042), insula (p = 0.035), cerebellum (p = 0.008), and limbic lobe (p = 0.049). FSS was associated with temporal lobe (r = −0.37, p = 0.013) and insular (r = −0.36, p = 0.019) volumes. The volumes of the same regions were also associated with EDSS. The global/regional atrophy results, assessed with automatic and easy-to-use software, correlated with cognitive and fatigue symptoms, thus supporting the clinical application in routine patient management
CSF levels of CXCL12 and osteopontin as early markers of primary progressive multiple sclerosis
Background and objectives: To evaluate the extent of intrathecal inflammation in patients with primary progressive MS (PPMS) at the time of diagnosis and to define markers and a specific inflammatory profile capable of distinguishing progressive from relapsing-remitting multiple sclerosis (RRMS). Methods: Levels of 34 pro- and anti-inflammatory cytokines and chemokines in the CSF were evaluated at the diagnosis in 16 patients with PPMS and 80 with RRMS. All patients underwent clinical evaluation, including Expanded Disability Status Scale assessment and a 3T brain MRI to detect white matter and cortical lesion number and volume and global and regional cortical thickness. Results: Higher levels of CXCL12 (odds ratio [OR] = 3.97, 95% CI [1.34-11.7]) and the monocyte-related osteopontin (OR = 2.24, 95% CI [1.01-4.99]) were detected in patients with PPMS, whereas levels of interleukin-10 (IL10) (OR = 0.28, 95% CI [0.09-0.96]) were significantly increased in those with RRMS. High CXCL12 levels were detected in patients with increased gray matter lesion number and volume (p = 0.001, r = 0.832 and r = 0.821, respectively). Pathway analysis confirmed the chronic inflammatory processes occurring in PPMS. Conclusions: At the time of diagnosis, a specific CSF protein profile can recognize the presence of early intrathecal inflammatory processes, possibly stratifying PPMS with respect to RRMS. Elevated CSF levels of CXCL12 and osteopontin suggested a key role of brain innate immunity and glia activity in MS. These molecules could represent useful candidate markers of MS progression, with implications for the pathogenesis and treatment of progressive MS. Classification of evidence: This study provides Class III evidence that CXCL12 and monocyte-related osteopontin may be correlated with PPMS, and IL-10 may be related to RRMS. It is may be correlated due to Bonferroni correction negating the statistical correlations found in the study
The use of the central vein sign in the diagnosis of multiple sclerosis: a systematic review and meta-analysis
Background: The central vein sign (CVS) is a radiological feature proposed as a multiple sclerosis (MS) imaging biomarker able to accurately differentiate MS from other white matter diseases of the central nervous system. In this work, we evaluated the pooled proportion of the CVS in brain MS lesions and to estimate the diagnostic performance of CVS to perform a diagnosis of MS and propose an optimal cut-off value. Methods: A systematic search was performed on publicly available databases (PUBMED/MEDLINE and Web of Science) up to 24 August 2020. Analysis of the proportion of white matter MS lesions with a central vein was performed using bivariate random-effect models. A meta-regression analysis was performed and the impact of using particular sequences (such as 3D echo-planar imaging) and post-processing techniques (such as FLAIR*) was investigated. Pooled sensibility and specificity were estimated using bivariate models and meta-regression was performed to address heterogeneity. Inclusion and publication bias were assessed using asymmetry tests and a funnel plot. A hierarchical summary receiver operating curve (HSROC) was used to estimate the summary accuracy in diagnostic performance. The Youden index was employed to estimate the optimal cut-off value using individual patient data. Results: The pooled proportion of lesions showing a CVS in the MS population was 73%. The use of the CVS showed a remarkable diagnostic performance in MS cases, providing a pooled specificity of 92% and a sensitivity of 95%. The optimal cut-off value obtained from the individual patient data pooled together was 40% with excellent accuracy calculated by the area under the ROC (0.946). The 3D-EPI sequences showed both a higher pooled proportion compared to other sequences and explained heterogeneity in the meta-regression analysis of diagnostic performances. The 1.5 Tesla (T) scanners showed a lower (58%) proportion of MS lesions with a CVS compared to both 3T (74%) and 7T (82%). Conclusions: The meta-analysis we have performed shows that the use of the CVS in differentiating MS from other mimicking diseases is encouraged; moreover, the use of dedicated sequences such as 3D-EPI and the high MRI field is beneficial
Atypical myelin oligodendrocyte glycoprotein antibody–associated optic neuritis and acute demyelinating polyneuropathy after SARS-CoV-2 infection: Case report and literature review
Post-infectious immune-mediated neurological complications of Sars-Cov-2 have been increasingly recognized since the novel pandemic emerged. We describe the case of a 74 years-old patient who developed a Myelin Oligodendrocyte Glycoprotein (MOG) antibody-associated unilateral retrobulbar optic neuritis a few weeks after paucisymptomatic COVID-19 disease and, subsequently, after the resolution of the optic neuritis, an acute inflammatory demyelinating polyneuropathy. So far, no cases of these two neurological manifestations have been reported in the same patient. We herein report a case characterized by both manifestations and review the accumulating literature regarding MOG antibody-associated disease following SarsCov-2 infection
Voxel-based morphometry and task functional magnetic resonance imaging in essential tremor: evidence for a disrupted brain network
The pathophysiology of essential tremor (ET) is controversial and might be further elucidated by advanced neuroimaging. Focusing on homogenous ET patients diagnosed according to the 2018 consensus criteria, this study aimed to: (1) investigate whether task functional MRI (fMRI) can identify networks of activated and deactivated brain areas, (2) characterize morphometric and functional modulations, relative to healthy controls (HC). Ten ET patients and ten HC underwent fMRI while performing two motor tasks with their upper limb: (1) maintaining a posture (both groups); (2) simulating tremor (HC only). Activations/deactivations were obtained from General Linear Model and compared across groups/tasks. Voxel-based morphometry and linear regressions between clinical and fMRI data were also performed. Few cerebellar clusters of gray matter loss were found in ET. Conversely, widespread fMRI alterations were shown. Tremor in ET (task 1) was associated with extensive deactivations mainly involving the cerebellum, sensory-motor cortex, and basal ganglia compared to both tasks in HC, and was negatively correlated with clinical tremor scales. Homogeneous ET patients demonstrated deactivation patterns during tasks triggering tremor, encompassing a network of cortical and subcortical regions. Our results point towards a marked cerebellar involvement in ET pathophysiology and the presence of an impaired cerebello-thalamo-cortical tremor network
Insights into single-timepoint ASL hemodynamics: what visual assessment and spatial coefficient of variation can tell
Purpose: Arterial spin labeling (ASL) represents a noninvasive perfusion biomarker, and, in the study of nonvascular disease, the use of the single-timepoint ASL technique is recommended. However, the obtained cerebral blood flow (CBF) maps may be highly influenced by delayed arterial transit time (ATT). Our aim was to assess the complexity of hemodynamic information of single-timepoint CBF maps using a new visual scale and comparing it with an ATT proxy, the "coefficient of spatial variation" (sCoV). Material and methods: Individual CBF maps were estimated in a memory clinic population (mild cognitive impairment, dementia and cognitively unimpaired controls) and classified into four levels of delayed perfusion based on a visual rating scale. Calculated measures included global/regional sCoVs and common CBF statistics, as mean, median and standard deviation. One-way ANOVA was performed to compare these measures across the four groups of delayed perfusion. Spearman correlation was used to study the association of global sCoV with clinical data and CBF statistics. Results: One hundred and forty-four participants (72 ± 7 years, 53% women) were included in the study. The proportion of maps with none, mild, moderate, and severe delayed perfusion was 15, 20, 37, and 28%, respectively. SCoV demonstrated a significant increase (p < 0.05) across the four groups, except when comparing none vs mild delayed perfusion groups (pBonf > 0.05). Global sCoV values, as an ATT proxy, ranged from 67 ± 4% (none) to 121 ± 24% (severe delayed) and were significantly associated with age and CBF statistics (p < 0.05). Conclusion: The impact of ATT delay in single-time CBF maps requires the use of a visual scale or sCoV in clinical or research settings
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