Background. Astrocytomas and oligodendrogliomas together account for about half of all cases of adult-type diffuse gliomas. These tumors differ in their sensitivity to radiation therapy and pharmaceutical treatment. Despite the presence of specific radiological patterns, differential diagnosis of these tumors by magnetic resonance imaging (MRI) remains quite challenging, and they are often indistinguishable on standard MR images.

Objective. To assess the potential of magnetic resonance imaging weighted by amide proton transfer (APT-weighted imaging) in the differential diagnosis of diffuse astrocytomas and oligodendrogliomas.

Materials and Methods. MRI scans were performed on 26 patients aged 22 to 71 years with histologically confirmed diffuse astrocytomas and oligodendrogliomas Grade 2 and Grade 3. The examinations were conducted on a Philips Elition X 3T scanner. The MRI protocol included standard sequences and images weighted by amide proton transfer (APT-weighted imaging). Mean, minimum, and maximum values of APT-signal were obtained in the central and peripheral tumor regions (both absolute and normalized to white matter), as well as in normal white matter.

Results. No differences were found in the absolute numerical values of the APT-weighted signal. Astrocytomas Grade 2 and Grade 3 had higher normalized maximum RCAG values in the peripheral part of the tumor with an index of attenuation of minimal APT signal values of 3.42 [2.82; 4.15] compared to oligodendrogliomas — 2.49 [2.05; 2.65] (p = 0.009, Mann — Whitney test). At a cutoff value of 2.99 for normalized maximum values in the peripheral area, the sensitivity for detecting astrocytoma Grade 2–3 was 76.9 %, specificity was 84.6 %, and area under the curve was 0.799.

Conclusion. The use of images weighted by amide proton transfer improves the effectiveness of MRI in the differential diagnosis between astrocytomas and oligodendrogliomas Grade 2–3.

Objective. This study aimed to conduct a comprehensive analysis of the potential of combined use of Amide Proton Transfer (APT) imaging and standardized VASARI (Visually AcceSAble Rembrandt Images) features for predicting molecular characteristics (IDH1 status, 1p19q codeletion) and the grade (differentiating Grade 3 from Grade 4) in patients with diffuse gliomas.

Materials and Methods. A prospective pilot study included 40 patients with morphologically verified diffuse gliomas. All patients underwent preoperative MRI on a 3T scanner, including an APT sequence, as well as ASL and DWI (with ADC calculation). Quantitative assessment of APT, ASL, and ADC was performed, along with a qualitative analysis of 25 morphological features according to the VASARI system, followed by multiple correspondence analysis to identify latent components. Machine learning methods (Random Forest, XGBoost, Logistic Regression, Support Vector Machine, Multinomial Regression) were applied for classification tasks. The performance of models based solely on quantitative MRI parameters (mean APT, ADC, ASL values) was compared with models that additionally included VASARI components.

Results. APT values significantly differed between gliomas of different grades (p = 0.004), while ASL and ADC showed no significant differences. The extracted VASARI components explained 37.2 % of the variance, with the first and most significant component (VASARI MC1), reflecting the tumor's invasive potential, demonstrating a strong correlation with APT (r = 0.65, p < 0.001). The best results were achieved in predicting IDH1 status: a Random Forest model incorporating VASARI features showed an accuracy = 0.9 and AUC = 0.91, which was significantly higher than models based solely on quantitative parameters (accuracy 0.8, AUC 0.81). Predicting the presence/absence of 1p19q codeletion and differentiating Grade 3 from Grade 4 tumors proved to be more challenging tasks, and the addition of VASARI did not lead to a significant improvement in the models.

Conclusion. The combined use of quantitative APT parameters and standardized visual assessment using the VASARI system demonstrates significant potential for the non-invasive prediction of molecular-genetic characteristics of diffuse gliomas, particularly IDH1 status. The integration of qualitative and quantitative MRI data allows for the creation of more accurate diagnostic models, which may contribute to the personalization of patient treatment strategies.

Objective. Classic trigeminal neuralgia (TN) is a common chronic pain syndrome whose pathogenesis is not limited to the trigeminal system. Despite significant progress in understanding its mechanisms, data on the role of morphological changes in the cerebral cortex remain limited. In this study, we assessed cortical myeloarchitecture using T1w/T2w mapping, a post-processing method for MRI images. The T1w/T2w ratio is considered a reliable marker of myelin content in the cortex and is currently being explored as a promising clinical biomarker.

Materials and Methods. The study involved 41 patients with unilateral classical TN and 40 healthy volunteers. All participants underwent high-resolution brain MRI with 3D T1-weighted and 3D T2-weighted images. In the first stage, automatic cortex par-cellation was performed using FreeSurfer version 7.4.1 software. T1w/T2w ratio maps were then constructed using the MRTool (SPM12) package. The resulting T1w/T2w ratio maps were coregistered with the cortex parcellation results, after which mean values were extracted for each region according to the Desikan — Killiany atlas. For statistical analysis, analyses of covariance (ANCOVA) were performed, where group membership (patients with TN, healthy volunteers) was considered as an intergroup factor, the T1w/T2w ratio values in different areas of the cerebral cortex were considered as a dependent variable, and the age and gender of the patients were taken into account as covariates.

Results. In the group of patients with trigeminal neuralgia, compared with the group of healthy volunteers, a statistically significant decrease in the mean T1w/T2w ratio was found in the regions of the left hemisphere, including the inferior parietal lobule, isthmus and posterior cingulate gyrus, lateral occipital, parahippocampal, and precen-tral cortex (p < 0.05, FDR-corrected). In the right hemisphere, a decrease in T1w/T2w values was observed in the lateral occipital, fusiform, lingual, and transverse temporal cortex (p < 0.05, FDR-corrected).

Conclusion. Our results indicate that classical trigeminal neuralgia is associated with myeloarchitectonic changes in individual areas of the cerebral cortex, reflecting the complex nature of the pathogenesis of this condition.

The relevance of this study is driven by the need to develop an objective neuroimaging criterion for the early diagnosis and prediction of long-term neurological outcomes in patients with diffuse axonal injury (DAI). A comprehensive assessment of the condition of major neural pathways using modern imaging techniques such as diffusion tensor MRI (DTI) and HARDI-CSD, followed by follow-up observation, represents a new and promising direction in neurotrauma.

Aim. To analyze the relationship between fractional anisotropy (FA) parameters in the corticospinal and arcuate tracts of the cerebral white matter and key neurological status indicators and functional outcomes in patients with acute diffuse axonal injury (DAI).

Materials and Methods. The study included 74 patients with DAI and 12 healthy volunteers. In the acute phase (within 1 month) of traumatic brain injury (TBI), all DAI patients underwent diffusion tensor MRI (DTI), and an HARDI-CSD MRI sequence was also performed. The study involved analyzing the mean fractional anisotropy (FA) parameter along the entire length of the corticospinal and arcuate tracts, with subsequent correlation to long-term functional outcomes (assessed no earlier than 3 months post-injury).

Results. Significant differences in FA parameters (p < 0.001) were found between healthy volunteers and DAI patients, as well as between patients with and without motor/speech impairments. Patients with unfavorable outcomes showed significant decrease in FA parameters in both corticospinal (p < 0.001) and arcuate tracts (p = 0.003–0.007) compared to the favorable outcome group. Reduction of FA in corticospinal tracts to 0.47–0.54 during the acute injury phase demonstrated high predictive value for motor impairments (AUC = 0.98–0.99), while decrease in arcuate tract FA to 0.39—0.45 was associated with speech disorders (AUC = 0.90–0.95).

Conclusion. The FA parameter is informative for differentiating between healthy and impaired cerebral pathways and predicting outcomes in DAI.

Pharmacoresistant epilepsy remains a significant challenge in modern neurology, affecting around 30 % of patients who do not respond to medication. Conventional neuroimaging methods often fail to provide sufficient diagnostic information in patients with MRI-negative findings and discordant EEG and MRI data. Optimizing preoperative mapping through noninvasive, high-precision neuroimaging techniques is critical to improving surgical outcomes and patient prognosis. Hybrid PET/MRI imaging with ¹⁸F-FDG offers new possibilities for enhanced preoperative localization in such patients.

Objective. To evaluate the diagnostic value and clinical applicability of hybrid PET/ MRI with ¹⁸F-FDG in the preoperative mapping of epileptogenic zones in patients with pharmacoresistant epilepsy, including MRI-negative cases. To perform a quantitative analysis of ¹⁸F-FDG hypometabolism in relation to the type of epilepsy, as well as the frequency and duration of epileptic seizures.

Materials and Methods. A screening of 10 healthy volunteers and an evaluation of 130 patients with drug-resistant epilepsy were performed according to the hybrid PET/MRI protocol with ¹⁸F-FDG. Both qualitative and quantitative analyses of hypometabolic brain regions were conducted, with findings correlated to clinical data, video-EEG monitoring results, and MRI findings. This approach enabled integrated assessment of functional and structural abnormalities, provided improved localization of epileptogenic zones, and facilitated the interpretation of metabolic, electrophysiological, and neuroanatomical correlates in the study cohort.

Results. The use of interictal brain PET/MRI with ¹⁸F-FDG significantly improved the detection rate of epileptogenic zones compared with standalone epilepsy-protocol MRI. This effect was particularly pronounced in MR-negative cases and in patients with subtle structural abnormalities, which were subsequently recognized upon targeted MRI re-evaluation guided by metabolic findings from PET imaging. In healthy individuals, no significant interhemispheric asymmetry of glucose metabolism was observed; physiologically, temporal regions demonstrate lower SUV values compared with frontal, parietal, and occipital cortices. Across all age groups of patients with pharmacoresistant epilepsy, moderate interhemispheric asymmetry of ¹⁸F-FDG metabolism was identified (asymmetry index range ~ 0.25–0.5). Disease duration and seizure frequency showed no clear linear relationship with focal SUV values. However, in MRI-positive cases with daily seizures, a relative increase in SUV within the epileptogenic focus was noted, likely reflecting postictal metabolic activity without materially affecting overall hemispheric asymmetry. The most pronounced ¹⁸F-FDG hypometabolism was observed in structural focal epilepsy, while higher metabolic activity characterized focal epilepsy of unknown etiology and mixed focal-generalized forms. These findings emphasize that hybrid ¹⁸F-FDG PET/MRI provides an advanced diagnostic advantage through its ability to integrate metabolic and structural data, allowing for improved localization of epileptogenic foci — even in subtle or MRI-negative cases — and thereby enhancing presurgical evaluation and treatment planning.

Conclusion. The use of hybrid ¹⁸F-FDG PET/MRI expands the diagnostic capabilities of neuroimaging in patients with focal pharmacoresistant epilepsy. Incorporation of PET/MRI into the presurgical planning workflow has the potential to improve the effectiveness of surgical treatment and enhance patient quality of life.

Hypoxia is one of the leading causes of impaired intrauterine development and adverse perinatal outcomes. The T2*-relaxometry method, based on the BOLD effect, enables noninvasive quantitative assessment of tissue oxygenation. Apparent diffusion coefficient (ADC) mapping is employed in the diagnosis of cerebral ischemia and serves as a quantitative biomarker of prenatal brain maturation.

Objective. To compare the utility of T2*-relaxometry and ADC mapping in assessing gestational characteristics, as well as hypoxic conditions of the fetal brain and placenta.

Materials and Methods. A retrospective cross-sectional analysis was conducted on 200 prenatal MRI examinations performed between 18 and 38 weeks of gestation (WG) from 2024 to 2025, using 1.5 T and 3 T Philips scanners at the MTC SB RAS (Novosibirsk, Russia). T2*- relaxometry was performed using a multi-echo single-shot echo-planar imaging (SS-EPI) sequence with TE ranging from 25 to 225 ms. ADC mapping was conducted using single-shot diffusion-weighted imaging (SSh DWI) with b-values of 0 and 700 s/mm². T2*-relaxation times (RT) and ADC values were obtained through ROI analysis of manually segmented regions of the brain and placenta. Statistical analysis included the Shapiro — Wilk test, Pearson and Spearman correlations, paired t-test, ANOVA, and Kruskal — Wallis test, with significance set at p < 0.05.

Results. T2*-mapping of the brain in 110 fetuses (66 scanned at 1.5 T; 44 at 3 T) and of the placenta in 50 cases (30 at 1.5 T; 20 at 3 T) demonstrated a decrease in T2*-RT with advancing gestational age (p = 0.0018 for the brain, p = 0.05 for the placenta). ADC values of the fetal brain (n = 126) were also inversely correlated with gestational age (p = 0.0135), whereas no significant gestational dependence was found for placental T2*-RT or ADC values (p > 0.209). Group analysis revealed a significant reduction in fetal brain T2*-RT after 29 WG compared to fetuses before 29 WG (p = 0.001).

Conclusions. Both T2*-RT and ADC values of the fetal brain are significantly influenced by gestational age, with more pronounced changes observed in the third trimester. T2*-relaxometry and ADC mapping are applicable for quantitative evaluation of fetal brain and placental deve- lopment and hold potential for early, noninvasive detection of hypoxic conditions.

Objective. To review and analyze state of the art contrast-enhanced magnetic resonance imaging (MRI) for diagnosing the causes of cochleovestibular syndrome, with a particular focus on visualizing endolymphatic hydrops and differential diagnosis of the main pathologies.

Materials and Methods. An analysis of MRI techniques was conducted. Protocols for examinations involving intravenous and intratympanic contrast medium administration, as well as the use of high-field machines (3 Tesla) and specialized pulse sequences for visualizing inner ear structures, were examined. Particular attention was paid to imaging protocols, including delayed contrast enhancement, for identifying endolymphatic hydrops, a key pathomorphological substrate of Ménière's disease.

Results. Key MRI signs of the main diseases manifesting as cochleovestibular syndrome are demonstrated: Meniere's disease, intralabyrinthine schwannoma, labyrinthitis, and endolymphatic sac tumor. A technique for visualizing and grading endolymphatic hydrops is described in detail. Two contrast-enhancing methods are compared, identifying their advantages and limitations.

Conclusion. Contrast-enhanced MRI, especially with delayed enhancement, is a highly informative and safe method for diagnosing the causes of cochleovestibular syndrome. MRI not only allows for the exclusion of tumors but also visualization of endolymphatic hydrops, which is crucial for diagnosing Ménière's disease. Standardized protocols and a multidisciplinary approach are essential for improving the accuracy and reproducibility of results.