Gergely Orsi

Background: The diffusion tensor image analysis along the perivascular space (DTI‐ALPS) index is an established term, and ongoing research aims to explore underlying mechanisms. Hypothesis: DTI‐ALPS measures are influenced by subject‐specific orientational differences of the projection and association fibers. Study Type: Prospective. Subjects: Forty‐four healthy adults (age: 22.1 ± 1.9 years; 19 males). Field Strength/Sequence: 3 T/diffusion‐weighted spin‐echo echo‐planar imaging. Assessment: DTI‐ALPS index was calculated by three methods using delineations of four observers (17‐, 4‐, 5‐, 3‐years of experience): (1) following vector registration to an atlas (Method 1); (2) after achieving zero projection for the relevant tracts by x ‐axis rotation (Method 2); and (3) based on the second and third diffusion tensor eigenvalues (Method 3). Effects of deviation from the expected anatomical orientation of ALPS‐associated tracts were also analyzed. Statistical Tests: Intraclass correlation coefficients (ICCs) were calculated among observers and methods. Friedman and Wilcoxon tests were used, respectively, for inter‐method and inter‐hemispheric comparisons. Spearman correlation and multiple‐linear regression assessed whether tract orientation deviation introduced bias in ALPS estimation. Significance level was p < 0.05. Results: Inter‐observer ICCs were excellent for average‐measures (≥ 0.90) and mostly good for single‐measures (0.90 > ICC ≥ 0.80). ALPS values differed significantly among methods, with significantly higher values for methods reducing bias due to deviation from the expected anatomical orientation of ALPS‐associated tracts (bilateral DTI‐ALPS index averaged across observers: 1.49 ± 0.13 vs. 1.59 ± 0.13 and 1.66 ± 0.13 for Methods 1–3 respectively). Left DTI‐ALPS index was significantly higher than the right for all 3 methods (averaged values across observers: 1.54 ± 0.14 vs. 1.44 ± 0.13; 1.65 ± 0.14 vs. 1.52 ± 0.13; 1.73 ± 0.14 vs. 1.59 ± 0.13). Inter‐method ICCs showed good‐to‐excellent consistency across all method pairs (≥ 0.80), but absolute ICCs were not always acceptable. Deviations from the expected orientation of ALPS‐associated tracts significantly affected ALPS values, especially for the left projection pathway (Spearman's rho: −0.503 to −0.376 for the bilateral index). Data Conclusion: DTI‐ALPS measures based on diffusion along Cartesian axes are influenced by off‐axis orientation of ALPS‐associated fibers, indicating that the DTI‐ALPS index is statistically significantly confounded by non‐glymphatic factors. Level of Evidence: 2. Technical Efficacy: Stage 1.

Background/Objectives: Dizziness is a frequent medical complaint with neurological, otolaryngological, and psychological origins. Imaging studies such as CT (Computer Tomography), cervical X-rays, and ultrasound aid diagnosis, while MRI (Magnetic Resonance Imaging) is crucial for detecting brain abnormalities. Our purpose is to identify structural brain changes associated with vertigo, assess pre-MRI diagnostic approaches, and evaluate treatment strategies. Methods: A case-control study of 232 vertigo patients and 232 controls analyzed MRI findings, pre-MRI examinations, symptoms, and treatments. Statistical comparisons were performed using chi-square and t-tests (p < 0.05). Results: White matter lesions, lacunar infarcts, Circle of Willis variations, and sinusitis were significantly more frequent in vertigo patients (p < 0.05). Pre-MRI diagnostics frequently identified atherosclerosis (ultrasound) and spondylosis (X-ray). Common symptoms included headache, imbalance, and visual disturbances. The most frequent post-MRI diagnosis was Benign Paroxysmal Positional Vertigo (BPPV). Treatments included lifestyle modifications, physical therapy (e.g., Epley maneuver), and pharmacological therapies such as betahistine. Conclusions: MRI revealed structural brain changes linked to vertigo. Pre-MRI assessments are essential for ruling out vascular and musculoskeletal causes. A multidisciplinary treatment approach is recommended. Trial Registration: This study was registered in ClinicalTrials.gov with the trial registration number NCT06848712 on 22 February 2025.

The DTI-ALPSindex (diffusion tensor image analysis along the perivascular space index) has been tested in several diseases, but a limited number of studies are available in healthy normal populations. Given that some of the examined diseases show asymmetric features (e.g. Parkinson’s disease, epilepsy) and considering that the DTI-ALPSindex is calculated from white matter regions involved in motor and language functions, our aim was to examine whether the index is influenced by handedness and/or functional language lateralisation. Eighty-two Caucasian adults (35 males; mean age: 26.91 ± 10.17, range: 18–66 years) were included in this retrospective cross-sectional study. Handedness was assessed by the Edinburgh Handedness Inventory, while language lateralisation was determined by functional MRI at 3T using a verbal fluency paradigm. The left- and right-hemispheric as well as the bilateral DTI-ALPS indices were calculated independently by two observers. Multiple linear regression corrected for age and sex indicated that handedness was inversely related to the left ALPSindex by Observer1 (n = 81, two-tailed P = 0.030) and the bilateral ALPSindex by both observers (n = 82, P = 0.025 and P = 0.044), but not significantly related to the right ALPSindex. In females, multiple linear regression corrected for age indicated that language laterality index was inversely related to the left ALPSindex (n = 47, P < 0.001) and the bilateral ALPSindex (n = 47, P ≤ 0.003) by both observers, but not significantly associated with the right ALPSindex. In males, language laterality index was not related to any of the ALPS indices. Providing further insights into the normal DTI-ALPS patterns, our study supports the hypothesis that both language laterality and handedness can affect DTI-ALPS index that should be considered in future studies.

Background/Objectives: Headache is one of the most common neurological symptoms associated with COVID-19, affecting approximately 25% of patients. While most headaches resolve within weeks, some persist for months, suggesting underlying structural brain changes. This study aimed to identify brain MRI abnormalities associated with chronic headaches in patients with a history of COVID-19 infection. Methods: This retrospective study included 30 patients with post-COVID-19 headaches and 30 control patients with no history of COVID-19. Demographic characteristics were analyzed using t-tests and chi-square tests. MRI findings were categorized into six types: cortical atrophy, white matter lesions, vascular lesions, lacunar lesions, vascular encephalopathy, and sinusitis. Differences in MRI findings between the two groups were evaluated using chi-square tests. Secondary outcomes included the analysis of symptoms accompanying headaches, diagnoses following MRI, and treatments applied. Results: White matter lesions were significantly more frequent in the post-COVID-19 group (50%) compared to controls (20%) (p = 0.015). Conversely, sinusitis was more prevalent in the control group (36.7%) than in the post-COVID-19 group (6.7%) (p = 0.005). Other MRI abnormalities showed no significant differences. Cognitive dysfunction (30%) and dizziness (33.3%) were the most common associated symptoms. The most frequent diagnoses after MRI in the post-COVID-19 group were headaches/migraines (23.3%), post-COVID-19 headache (20%), and vestibular syndrome (13.3%). Conclusions: Persistent post-COVID-19 headaches may be linked to structural white matter changes observed in MRI. Further research, ideally including pre-infection imaging data, is needed to determine the causal relationship between these lesions and chronic headache symptoms. Trial Registration: This study was registered in ClinicalTrials with the trial registration number NCT06825741 on 13 February 2025.

Resting-state functional magnetic resonance imaging (rs-fMRI) has been widely utilized to investigate plasticity mechanisms and functional reorganization in multiple sclerosis (MS). Among many resting state (RS) networks, a significant role is played by the salience network (SN, ventral attention network). Previous reports have demonstrated the involvement of osteopontin (OPN) in the pathogenesis of MS, which acts as a proinflammatory cytokine ultimately leading to neurodegeneration. Concentration of serum OPN was related to MRI findings 10.22±2.84 years later in 44 patients with MS. Local and interhemispheric correlations (LCOR, IHC), ROI-to-ROI and seed-based connectivity analyses were performed using serum OPN levels as independent variable along with age and gender as nuisance variables. We found significant associations between OPN levels and local correlation in right and left clusters encompassing the central opercular- and insular cortices (p-FDR = 0.0018 and p-FDR = 0.0205, respectively). Moreover, a significant association was identified between OPN concentration and interhemispheric correlation between central opercular- and insular cortices (p-FDR = 0.00015). Significant positive associations were found between OPN concentration and functional connectivity (FC) within the SN (FC strength between the anterior insula ventral division and 3 other insular regions, F(2,13) = 7.84, p-FDR = 0.0117). Seed-based connectivity analysis using the seven nodes of the SN resulted in several positive and inverse associations with OPN level. Serum OPN level may predict FC alterations within the SN in 10 years.

Nowadays, the limitless availability to the World Wide Web can lead to general Internet misuse and dependence. Currently, smartphone and social media use belong to the most prevalent Internet-related behavioral addiction forms. However, the neurobiological background of these Internet-related behavioral addictions is not sufficiently explored. In this study, these addiction forms were assessed with self-reported questionnaires. Resting-state functional magnetic resonance imaging was acquired for all participants (n = 59, 29 males) to examine functional brain networks. The resting-state networks that were discovered using independent component analysis were analyzed to estimate within network differences. Significant negative associations with social media addiction and smartphone addiction were found in the language network, the lateral visual networks, the auditory network, the sensorimotor network, the executive network and the frontoparietal network. These results suggest that problematic smartphone and social media use are associated with sensory processing and higher cognitive functioning.

Background: Although COVID‐19 is primarily an acute respiratory infection, 5%–40% of patients develop late and prolonged symptoms with frequent neurological complaints, known as long COVID syndrome. The presentation of the disease suggests that COVID infection may cause functional and/or morphological central nervous system alterations, but studies published in the literature report contradictory findings.Purpose: To investigate the chronic effects of COVID‐19 on cerebral grey matter in a group of young patients without comorbidities, with mild course of COVID infection and no medical complaints at the time of examination.Study Type: Prospective.Population: Thirty‐eight young (age = 26.6 ± 5.0 years; male/female = 14/24), adult participants who recovered from mild COVID infection without a history of clinical long COVID and 37 healthy control subjects (age = 25.9 ± 2.8 years; male/female = 14/23).Field Strength/Sequence: Three Tesla, 3D T1‐weighted magnetization‐prepared rapid gradient‐echo, 2D T2‐weighted turbo spin‐echo.Assessment: MRI‐based morphometry and volumetry along with neuropsychological testing and self‐assessed questionnaire.Statistical Tests: Fisher's exact test, Mann–Whitney U‐test, and multiple linear regression analyses were used to assess differences between COVID and healthy control groups. P < 0.05 was used as cutoff for significance.Results: In the COVID group, significantly lower bilateral mean cortical thickness (left/right‐hemisphere: 2.51 ± 0.06 mm vs. 2.56 ± 0.07 mm, η²_p = 0.102/2.50 ± 0.06 mm vs. 2.54 ± 0.07 mm, η²_p = 0.101), lower subcortical gray matter (57881 ± 3998 mm³ vs. 60470 ± 5211 mm³, η²_p = 0.100) and lower right olfactory bulb volume (52.28 ± 13.55 mm³ vs. 60.98 ± 15.8 mm³, η²_p = 0.078) were found. In patients with moderate to severe anosmia, cortical thickness was significantly lower bilaterally, as compared to patients without olfactory function loss (left/right‐hemisphere: 2.50 ± 0.06 mm vs. 2.56 ± 0.05 mm, η² = 0.173/2.49 ± 0.06 mm vs. 2.55 ± 0.05 mm, η² = 0.189). Using further exploratory analysis, significantly reduced cortical thickness was detected locally in the right lateral orbitofrontal cortex in the COVID group (2.53 ± 0.10 mm vs. 2.60 ± 0.09 mm, η²_p = 0.112).Data Conclusion: Even without any subjective or objective neurological complaints at the time of the MR scan, subjects in the COVID group showed gray matter alterations in cortical thickness and subcortical gray matter volume.Level of Evidence: 2Technical Efficacy: Stage 3