Neuroimaging Methods Research Articles

Neural signatures of imaginary motivational states: desire for music, movement and social play

The literature has demonstrated the potential for detecting accurate electrical signals that correspond to the will or intention to move, as well as decoding the thoughts of individuals who imagine houses, faces or objects. This investigation examines the presence of precise neural markers of imagined motivational states through the combining of electrophysiological and neuroimaging methods. 20 participants were instructed to vividly imagine the desire to move, listen to music or engage in social activities. Their EEG was recorded from 128 scalp sites and analysed using individual standardized Low-Resolution Brain Electromagnetic Tomographies (LORETAs) in the N400 time window (400–600 ms). The activation of 1056 voxels was examined in relation to the 3 motivational states. The most active dipoles were grouped in eight regions of interest (ROI), including Occipital, Temporal, Fusiform, Premotor, Frontal, OBF/IF, Parietal, and Limbic areas. The statistical analysis revealed that all motivational imaginary states engaged the right hemisphere more than the left hemisphere. Distinct markers were identified for the three motivational states. Specifically, the right temporal area was more relevant for “Social Play”, the orbitofrontal/inferior frontal cortex for listening to music, and the left premotor cortex for the “Movement” desire. This outcome is encouraging in terms of the potential use of neural indicators in the realm of brain-computer interface, for interpreting the thoughts and desires of individuals with locked-in syndrome.

Intracortical brain-heart interplay: An EEG model source study of sympathovagal changes.

The interplay between cerebral and cardiovascular activity, known as the functional brain-heart interplay (BHI), and its temporal dynamics, have been linked to a plethora of physiological and pathological processes. Various computational models of the brain-heart axis have been proposed to estimate BHI non-invasively by taking advantage of the time resolution offered by electroencephalograph (EEG) signals. However, investigations into the specific intracortical sources responsible for this interplay have been limited, which significantly hampers existing BHI studies. This study proposes an analytical modeling framework for estimating the BHI at the source-brain level. This analysis relies on the low-resolution electromagnetic tomography sources localization from scalp electrophysiological recordings. BHI is then quantified as the functional correlation between the intracortical sources and cardiovascular dynamics. Using this approach, we aimed to evaluate the reliability of BHI estimates derived from source-localized EEG signals as compared with prior findings from neuroimaging methods. The proposed approach is validated using an experimental dataset gathered from 32 healthy individuals who underwent standard sympathovagal elicitation using a cold pressor test. Additional resting state data from 34 healthy individuals has been analysed to assess robustness and reproducibility of the methodology. Experimental results not only confirmed previous findings on activation of brain structures affecting cardiac dynamics (e.g., insula, amygdala, hippocampus, and anterior and mid-cingulate cortices) but also provided insights into the anatomical bases of brain-heart axis. In particular, we show that the bidirectional activity of electrophysiological pathways of functional brain-heart communication increases during cold pressure with respect to resting state, mainly targeting neural oscillations in the , , and bands. The proposed approach offers new perspectives for the investigation of functional BHI that could also shed light on various pathophysiological conditions.

Open access EEG dataset of repeated measurements from a single subject for microstate analysis

Electroencephalography (EEG) microstate analysis is a neuroimaging analytical method that has received considerable attention in recent years and is widely used for analysing EEG signals. EEG is easily influenced by internal and external factors, which can affect the repeatability and stability of EEG microstate analysis. However, there have been few reports and publicly available datasets on the repeatability of EEG microstate analysis. In the current study, a 39-year-old healthy male underwent a total of 60 simultaneous electroencephalography and electrocardiogram measurements over a period of three months. After the EEG recording was completed, magnetic resonance imaging (MRI) was also conducted. To date, this EEG dataset has the highest number of repeated measurements for one individual. The dataset can be used to assess the stability and repeatability of EEG microstates and other analytical methods, to decode resting EEG states among subjects with open eyes, and to explore the stability and repeatability of cortical spatiotemporal dynamics through source analysis with individual MRI.

Echographic pattern features of dissections of the extracranial parts of the brachiocephalic arteries

Purpose: to determine the frequency of various ultrasound signs of dissections of the extracranial parts of the brachiocephalic arteries, as well as to compare the results of ultrasound and neuroimaging methods in the diagnostics of dissections.Materials and methods. The study included data on 108 patients, among them 44 (40.7%) women, 64 (59.3%) men, mean age was 56 ± 14 years. All patients underwent duplex scanning of the brachiocephalic arteries, 53 patients underwent CT-angiography, and 99 patients underwent MRI.Results. The sensitivity of duplex scanning in the primary diagnosis of dissections in our study was 97.2%. In 40 patients (37%) with dissections according to duplex scanning the presence of dissection was also confirmed on CT-angiography or MRI. Expansion of the vessel diameter and the presence of intramural hematoma (IMH), as well as their combination, were the most common ultrasound signs of dissections in our study. In cases where dissection was not confirmed by CT-angiography or MRI data moderate echogenicity of IMH was noted significantly more often (p = 0.018). Of all the ultrasound signs of dissections, the highest share of coincidence with the signs obtained with neuroimaging diagnostic methods occurred with IMG.Conclusion. The most frequently recorded ultrasound signs of dissections were the expansion of the vessel diameter and the presence of IMG, as well as their combination. The results of the study showed a high sensitivity of the ultrasound method in detecting dissections, especially in the subacute and chronic stages, as well as to determine the causes of ischemic stroke in the differential diagnosis of brachiocephalic artery pathologies.

A coupled-GAN architecture to fuse MRI and PET image features for multi-stage classification of Alzheimer’s disease

Alzheimer’s disease (AD) is a degenerative neurological ailment that begins with memory loss and ultimately leads to a total loss of mental capacity. Researchers are interested in using magnetic resonance imaging (MRI) and positron emission tomography (PET) to find people with mild cognitive impairment (MCI), which is a stage before Alzheimer’s disease (AD). Significant hippocampal loss and temporal lobe atrophy characterize the transition from MCI to AD, which can be visualized using T1-W structural MRI. PET visualizes brain glucose metabolism, which indicates neuronal activity, making it a viable neuroimaging method for AD diagnosis. The extraction and fusion of structural and metabolite information about brain alterations contained in multimodal data is crucial for achieving an appropriate classification result. Therefore, in this work a new end-to-end coupled-GAN (CGAN) architecture is introduced. The proposed CGANC network consists of two sub-models: a CGAN for extraction of fused features from multimodal data, and a CNN classifier to classify these features. The proposed CGAN model is trained to encode MRI and PET images into a shared latent space. The fused features are extracted from this shared latent space and then are classified according to particular stage of AD. In order to test the effectiveness of the suggested approach, experiments are done on the publicly available ADNI dataset and compared with state-of-the-art methods. The proposed method’s source code will be made freely available at https://github.com/ChandrajitChoudhury/CGAN-AD.

Proton magnetic resonance spectroscopy in children with some neurological and mental disorders accompanied by mental and speech development delay: a prospective study

Proton magnetic resonance spectroscopy in children with some neurological and mental disorders accompanied by mental and speech development delay: a prospective study

Functional magnetic resonance imaging of the brain in patients with insomnia: a prospective study

INTRODUCTION: Insomnia is one of the most common sleep disorders, the interest of scientists in the occurrence and pathophysiology of insomnia is growing every year. In particular, the brain connectome and its changes in sleep disorders are being actively studied based on the data of resting state functional magnetic resonance imaging.OBJECTIVE: The study is to assess changes in brain connectomes in patients with chronic insomnia using functional magnetic resonance imaging.MATERIALS AND METHODS: 53 people took part in the study, of which 34 patients who applied for a somnologist’s appointment at the Almazov National Research Medical Center of the Ministry of Health of the Russian Federation were diagnosed with chronic insomnia, confirmed by polysomnography. All participants of the study had an MRI of the brain on tomographs with a magnetic field induction force of 3.0 Tl at two time points.Statistics: Statistical analysis of MRI data was performed using MathLab 2018a, CONN v1.7. Descriptive statistics, the Kolmogorov-Smirnov criterion were used to process the materials, depending on the characteristics of the data, the MannWhitney U-criterion and Pearson Chi-squared were used to analyze demographic data.RESULTS: The study, neuroimaging markers of insomnia were identified and changes in the functional networks of the brain were described in patients with insomnia and a group of healthy volunteers at different time points.DISCUSSION: The obtained functional data demonstrate ambiguous results. Both an increase and a decrease in the functional connectivity of the medial prefrontal cortex with the structures of the visual analyzer, an increase in functional connections with the temporal pole, in particular with the hippocampus, is determined, which indicates changes in the consolidation of visually encoded information. The relative limitation in this study can be considered the heterogeneity of the age composition of the group.CONCLUSSION: Resting state functional MRI of the brain is a key neuroimaging method in determining the functional connections of the brain in patients with sleep disorders, which allows us to establish a impairment of functional interaction between brain structures involved in the processes of falling asleep and maintaining sleep.

[18F]2-fluoro-2-deoxy-sorbitol ([18F]FDS) PET imaging repurposed for quantitative estimation of blood-brain barrier permeability in a rat model of Alzheimer's disease

Numerous studies suggest that blood-brain barrier (BBB) dysfunction may contribute to the progression of Alzheimer's disease (AD). Clinically available neuroimaging methods are needed for quantitative "scoring" of BBB permeability in AD patients. [18F]2-fluoro-2-deoxy-sorbitol ([18F]FDS), which can be easily obtained from simple chemical reduction of commercial [18F]2-fluoro-2-deoxy-glucose ([18F]FDG), was investigated as a small-molecule marker of BBB permeability, in a pre-clinical model of AD using in vivo PET imaging. Chemical reduction of [18F]FDG to [18F]FDS was obtained with a 100% conversion yield. Dynamic PET acquisitions were performed in the APP/PS1 rat model of AD (TgF344-AD, n=3) compared with age-matched littermates (WT, n=4). The brain uptake of [18F]FDS was determined in selected brain regions, delineated from a coregistered rat brain template. The brain uptake of [18F]FDS in the brain regions of AD rats versus WT rats was compared using a 2-way ANOVA. The uptake of [18F]FDS was significantly higher in the whole brain of AD rats, as compared with WT rats (P<0.001), suggesting increased BBB permeability. Enhanced brain uptake of [18F]FDS in AD rats was significantly different across brain regions (P<0.001). Minimum difference was observed in the amygdala (+89.0±7.6%, P<0.001) and maximum difference was observed in the midbrain (+177.8±29.2%, P<0.001). [18F]FDS, initially proposed as radio-pharmaceutical to estimate renal filtration using PET imaging, can be repurposed for non-invasive and quantitative determination of BBB permeability in vivo. Making the best with the quantitative properties of PET imaging, it was possible to estimate the extent of enhanced BBB permeability in a rat model of AD.

ОСОБЕННОСТИ КЛИНИЧЕСКИХ ПРОЯВЛЕНИЙ ПРИ МАЛЬФОРМАЦИИ КИАРИ 0, 1 И «ПОГРАНИЧНОГО» ТИПОВ

Introduction. Introduction of advanced neuroimaging methods has made it possible to identify subtle structural features of the posterior cranial fossa and craniovertebral junction, as well as the dislocation of cerebellar tonsils into the foramen magnum, which have clinically overt and subclinical forms. Aim: To study the clinical manifestation features of Chiari type 0, 1, and “borderline” malformations. Materials and Methods. For literature analysis, the sources were used from international databases, such as Web of Science, Scopus, and PubMed, and the Russian library system, eLibrary. Results and Discussion. The most common pathology of the posterior cranial fossa is Chiari type 1 malformation associated with a mesodermal defect and with discrepancies between the sizes of the posterior cranial fossa and the neural structures that fill it. To assess the Chiari malformation grade, it is advisable to specify the dislocation grades of cerebellar tonsils. There is a common classification of cerebellar tonsil dislocations, in which the dislocation grade 1 of cerebellar tonsils is characterized by the descent of cerebellar tonsils below the foramen magnum level; grade 2 is inherent in dislocation of the cerebellar tonsils down to the C2 vertebra level in combination with displacing the pons and medulla oblongata below the Twining line. Grade 3 dislocation of the cerebellar tonsils is where the cerebellum tonsil displacement is combined with intracranial hypertension. In case of the degree 4 dislocation of the cerebellar tonsils, cerebellar hypoplasia is observed, accompanied by a displacement of the medulla oblongata. The occurrence of syringomyelia in Chiari type 0 malformation is associated with liquor dynamic disorders in the craniovertebral junction region; the similar liquor circulation disorders are detected in Chiari type 1 malformation. Chiari type 1 and “borderline”- type malformations manifest as persistent cranialgia, pain in the cervical spine, otoneurologic and visual disorders, respiratory, psychological, and cognitive disorders, damage to the cerebellar and stem structures of the brain, damage to the spinal cord, and other, more rare signs of damage to the central nervous system. Conclusions. Thus, it is necessary to further study the features of developing clinical symptoms in Chiari type 1, 0, and “borderline” malformations to assess the changes in the course of the disease and select an adequate treatment strategy.

Clinical and diagnostic features of repeated mild traumatic brain injuries

Repeated mild traumatic brain injury (TBI) leads to new changes and exacerbates the existing ones caused by the primary trauma. The pathogenetic mechanisms of repeated TBI are the result of traumatic effects and their cumulation. They cause various morphological and functional changes in the brain. Objective — to improve the diagnosis of pathological changes in patients with repeated mild traumatic brain injury. Materials and methods. The study involved 199 patients with a history of repeated mild TBI. Men predominated among them — 158 (79.40 %). There were 80 (40.20 %) patients of youthful age (17—24 years), 78 (39.20 %) of young age (25—44 years), and 41 (20.60 %) of middle-aged (45—60 years). The number of repeated TBIs per patient ranged from two to five. All patients were examined in the remote period of TBI. The control group consisted of 30 people aged 18 to 50 years (mean age — (33.11 ± 3.09) years) who had no history of TBI. Cognitive impairment (CI) was assessed by neuropsychological examination using the Mini-Mental State Examination (MMSE), the Frontal Area Battery (FAB), and the clock drawing test. Methods of neuropsychological analysis, neuroimaging and neurophysiological methods were used. The data of clinical and neurological examinations and studies of cognitive functions were analyzed, structural changes of the brain and cerebrospinal tract were established on the basis of neuroimaging studies of the brain, and the peculiarities of cerebral hemodynamics in patients with mild repeated TBI were determined. The characteristics of neurophysiological changes in patients are given based on the study of the features of electroencephalographic changes and the study of cognitive evoked potentials of the brain. The immune status was evaluated in patients who had repeated mild TBI. Results. Repeated TBI in our study was observed in the form of mild concussions and brain contusions. Their number in one patient ranged from 1 to 5. Clinical manifestations of repeated mild TBI had peculiarities: cephalalgic, cerebral and cerebrospinal hypertensive syndrome, cognitive impairment, diffuse neurological symptoms, and pyramidal insufficiency prevailed in the clinical picture. Only in the main group were cases of a combination of three to eight neurological syndromes detected. A decrease in cognitive function was found in patients with repeated mild TBI compared to the control group according to neuropsychological testing. The analysis of cognitive evoked potentials revealed an increase in the latent period of the cognitive complex P300 in patients with repeated TBI compared with the control group, indicating a decrease in cognitive function. More frequent CP was detected in the main group. The use of modern neuroimaging methods revealed that patients with repeated TBI had increased width of the lateral ventricles on both sides, ventricle III, and the cavity of the septum compared with the control group, as well as a higher frequency of expansion of the septum and convexity of the subarachnoid spaces. Patients with repeated mild TBI are characterised by an increase in blood flow velocity in the extracranial parts of the carotid basin and a decrease in velocity in the vessels of the vertebrobasilar basin with a change in vascular resistance, in the segments of the intracranial part of the carotid basin — a decrease in blood flow velocity without a change in vascular resistance. Disorders of venous cerebral circulation (increased velocity in the internal jugular vein and Rosenthal veins) were recorded in the majority of the main group. According to the data of the CEG, in patients with repeated TBI against the background of diffuse changes in brain bioelectrical activity, focal changes in the left hemisphere of the brain are more common. Dominant arrhythmia was recorded in 97.78 % of patients in the main group. The amplitude of arrhythmia in patients with repeated TBI is lower compared to the control group, and the frequency of arrhythmic oscillations is higher. Conclusions. The use of clinical and diagnostic control allows to prevent the development of damage and obtain objective information about the state of the brain and its structures.

Hierarchical Principal Components for Data-Driven Multiresolution fMRI Analyses.

Understanding the organization of neural processing is a fundamental goal of neuroscience. Recent work suggests that these systems are organized as a multiscale hierarchy, with increasingly specialized subsystems nested inside general processing systems. Current neuroimaging methods, such as independent component analysis (ICA), cannot fully capture this hierarchy since they are limited to a single spatial scale. In this manuscript, we introduce multiresolution hierarchical principal components analysis (hPCA) and compare it to ICA using simulated fMRI datasets. Furthermore, we describe a parametric statistical filtering method developed to focus analyses on biologically relevant features. Lastly, we apply hPCA to the Human Connectome Project (HCP) to demonstrate its ability to estimate a hierarchy from real fMRI data. hPCA accurately estimated spatial maps and time series from networks with diverse hierarchical structures. Simulated hierarchies varied in the degree of branching, such as two-way or three-way subdivisions, and the total number of levels, with varying equal or unequal subdivision sizes at each branch. In each case, as well as in the HCP, hPCA was able to reconstruct a known hierarchy of networks. Our results suggest that hPCA can facilitate more detailed and comprehensive analyses of the brain's network of networks and the multiscale regional specializations underlying neural processing and cognition.

Atypical Structure of Broca's Area in a Patient with Primary Progressive Atrophy Syndrome at the Onset of Alzheimer's Disease

This article presents a clinical case of Alzheimer’s disease with a debut as primary progressive aphasia syndrome. Insufficient use of routine magnetic resonance imaging in this case in the diagnosis of neurodegenerative diseases and the advantage of such additional neuroimaging methods as positron emission tomography, functional magnetic resonance imaging with a scale assessment of atrophic changes. Additional neuroimaging techniques have been shown to significantly improve the early detection of pathological changes in brain structures and to reveal the location of functional areas involved in the neurodegenerative process.

The Contribution of Functional Near-Infrared Spectroscopy (fNIRS) to the Study of Neurodegenerative Disorders: A Narrative Review.

Functional near-infrared spectroscopy (fNIRS) is an innovative neuroimaging method that offers several advantages over other commonly used modalities. This narrative review investigated the potential contribution of this method to the study of neurodegenerative disorders. Thirty-four studies involving patients with Alzheimer's disease (AD), mild cognitive impairment (MCI), frontotemporal dementia (FTD), Parkinson's disease (PD), or amyotrophic lateral sclerosis (ALS) and healthy controls were reviewed. Overall, it was revealed that the prefrontal cortex of individuals with MCI may engage compensatory mechanisms to support declining brain functions. A rightward shift was suggested to compensate for the loss of the left prefrontal capacity in the course of cognitive decline. In parallel, some studies reported the failure of compensatory mechanisms in MCI and early AD; this lack of appropriate hemodynamic responses may serve as an early biomarker of neurodegeneration. One article assessing FTD demonstrated a heterogeneous cortical activation pattern compared to AD, indicating that fNIRS may contribute to the challenging distinction of these conditions. Regarding PD, there was evidence that cognitive resources (especially executive function) were recruited to compensate for locomotor impairments. As for ALS, fNIRS data support the involvement of extra-motor networks in ALS, even in the absence of measurable cognitive impairment.

Study of the possibilities of non-invasive assessment of increased intracranial pressure according to MRI data on the example of patients with secondary intracranial hypertension

Modern methods of neuroimaging make it possible to develop approaches for assessing intracranial pressure as a replacement for the “gold standard” of invasive monitoring. Aim of the study was to investigate the possibility of using magnetic resonance (MR) characteristics to assess the increase in intracranial pressure in patients with secondary intracranial hypertension. Material and methods. Group 1 – 40 patients with brain tumors, group 2 – 15 patients with communicating hydrocephalus, control group – 36 individuals. The patients underwent MRI with measurement and evaluation of the optic nerve sheath diameter (ONSD), the optochiasmal cistern and the pituitary gland vertical sizes, and tortuosity of the ON. Patients of the 2nd group underwent a phase-contrast MRI with an assessment of the velocity and volumetric characteristics of blood and cerebrospinal fluid flows with the calculation of the intracranial compliance index (ICC). Using the FreeSurfer program, the brain volumes were estimated. Results and discussion. A statistically significant increase in ONSD was found in the groups of patients compared with the control group (by 24 %, p &lt; 0.05), decrease in the vertical size of the pituitary gland and an increase in the vertical size of the optochiasmal cistern (p &lt; 0.05), as well as ICC lowering in group 2 (by 1.7 times, p &lt; 0.05). Tortuosity of ON in group 1 was observed more often than in other groups. A statistically significant positive correlation between ONSD and brain volumes in group 1 (r = 0.55, p &lt; 0.05) and a negative correlation between brain volumes and ICC in group 2 (r = –0.86, p &lt; 0.05) has been found. Conclusions. Based on the presented results, we believe that the combined use of qualitative and quantitative MRI criteria can expand the diagnostic capabilities of non-invasive assessment of increased intracranial pressure.

Amplitude-integrated electroencephalography showed no differences in cerebral activity between preterm singletons and twins in the first 4 weeks of life.

Genetic influences on cerebral activity have been described previously, but data are scarce in preterms. We aimed to investigate whether a genetic influence causes amplitude-integrated electroencephalography (aEEG) signals to differ between singletons and twin preterm newborns. This was a retrospective single-centre study conducted at Innsbruck Medical University Hospital, Austria. Preterm infants born before 32 weeks of gestation between 6 November 2010 and 6 December 2022 were eligible for the study. The aEEG was analysed for the total maturation score, its component scores and the number of sleep-wake cycles per hour. We enrolled 240 preterm twin infants (57.5% male) with a mean gestational age of 30 (range: 24-32) weeks and a mean birth weight of 1324 (range: 600-2116) grams. We compared 240 singleton matched preterms. No differences were found between preterm singletons and twin preterm infants regarding the total maturation and component scores, or the number of sleep-wake cycles. aEEG showed no difference between monozygotic and dizygotic twins. Compared to singletons, twin infants born preterm showed no differences in aEEG signals in the first 4 weeks of life. Future studies should include more complex non-invasive functional neuroimaging methods to gain more insight into this important topic.

A novel restrainer device for acquistion of brain images in awake rats

Functional neuroimaging methods like fMRI and PET are vital in neuroscience research, but require that subjects remain still throughout the scan. In animal research, anesthetic agents are typically applied to facilitate the acquisition of high-quality data with minimal motion artifact. However, anesthesia can have profound effects on brain metabolism, selectively altering dynamic neural networks and confounding the acquired data. To overcome the challenge, we have developed a novel head fixation device designed to support awake rat brain imaging. A validation experiment demonstrated that the device effectively minimizes animal motion throughout the scan, with mean absolute displacement and mean relative displacement of 0.0256 (SD: 0.001) and 0.009 (SD: 0.002), across eight evaluated subjects throughout fMRI image acquisition (total scanning time per subject: 31 min, 12 s). Furthermore, the awake scans did not induce discernable stress to the animals, with stable physiological parameters throughout the scan (Mean HR: 344, Mean RR: 56, Mean SpO2: 94 %) and unaltered serum corticosterone levels (p = 0.159). In conclusion, the device presented in this paper offers an effective and safe method of acquiring functional brain images in rats, allowing researchers to minimize the confounding effects of anesthetic use.

Neurosurgery as an opportunity to correct symptoms of mental and behavioural disorders

Neurosurgical treatment for psychiatric disorders has a controversial history. This branch of neurosurgery called by developer of prefrontal leucotomy and Nobel prize laureate Egaz Moniz “psychosurgery”, was initially based not on scientific researches, but on enthusiasm of individuals and pressing social need. The outcome of psychosurgery regardless of its clinical benefits was the negative attitude of the broad masses and medical community, some countries have banned psychosurgery – the era of psychopharmacology has come. However, some patients suffering from severe course of the psychiatric disorder are resistant to conservative treatment.Over the last decades, the novel neuroimaging methods and neurobiological researches have considerably improved understanding of the pathogenesis of psychiatric disorders and scientific validity of the surgical intervention into the neural circuits. In this article, the main stages of the history of the psychiatric neurosurgery are briefly reviewed. Furthermore, the clinical and surgical considerations including the anatomic target localization, outcome and possible complications of the major operations which are still in practice are presented. The new neurosurgical techniques such as deep brain stimulation and gamma knife stereotactic radiosurgery were also considered. The part of the article is devoted to ethical, legal and terminological issues of psychiatric neurosurgery.

Agreement between Fetal Brain Ultrasonography and Magnetic Resonance Imaging in the Measurements of the Corpus Callosum and Transverse Cerebellar Diameter.

As the use of magnetic resonance imaging of the fetal brain has evolved, the need to understand its efficiency in the biometry of the fetal brain has broadened. This study aimed to assess the level of agreement and correlation between the two cardinal imaging methods of fetal neuroimaging, ultrasonography (US) and magnetic resonance imaging (MRI), by measuring the corpus callosum (CC) and transverse cerebellar diameter (TCD) in terms of length and percentile. Measurements of CC and TCD length and percentile were documented over a 7-year span in a tertiary referral medical center. All US and MRI examinations were performed in the customary planes and subcategorized by valid reference charts. Exclusion and inclusion criteria were set before the collection and processing of the data. A total of 156 fetuses out of 483 were included in the study. A positive, strong correlation and agreement were found (r = 0.78; ICC = 0.76) between US and MRI in TCD measurements. For CC length measurement, a moderate correlation and moderate agreement (r = 0.51; ICC = 0.49) between US and MRI was observed. TCD and CC percentiles had lower levels of correlation and agreement compared with the length variables. Our study indicates good agreement between MRI and US in the assessment of TCD measurement as a part of antenatal neuroimaging. Furthermore, while the two techniques are not always compatible, they are complementary methods.

The current state of the problem of diagnosis and therapy of depressive disorders (a literature review)

The article presents the results of an analytical review of current literature data on the problem of diagnosis and treatment of depressive disorders. The issues of a high incidence and polymorphism of the clinical presentation of these disorders are considered. The tendency towards formalization and objectification in the process of diagnosing depressive disorders in modern psychiatric discourse is covered, in particular, through the use of neuroimaging, neurophysiological and biochemical methods with the involvement of machine learning and artificial intelligence technologies. The classic method of a structured or semi-structured interview, as a tool for diagnosing clinical depression, currently remains one of the most common, but it has certain limitations and disadvantages, the most significant of which are a considerable degree of the method subjectivity and its dependence on the perception by specialists conducting the diagnosis, that causes low sensitivity and specificity of this method. The significant role of a general practitioner as a key link in the identification and treatment of the described phenomena, which automatically presents to these specialists a number of professional, qualification and personal requirements, such as knowing pathogenesis of depressive disorders, the features of their pharmacotherapy, skills to build compliant relationships with patients, is highlighted apart. The article also emphasizes the lack of information in available sources about measures to assess the risk of depressive episode recurrence, as well as insufficient attention to the methods of neurophysiological examination and their narrow arsenal. Thus, based on the results of the review, it has been found that a promising direction to improve diagnosis and assessment of therapeutic measure effectiveness, as a part of follow-up among patients with depression, in addition to classical psychodiagnostic tools, is the development and implementation of ethological and neurophysiological methods of examination for objectifying evaluation of patients’ condition and elimination of subjective factors associated with specialists’ perception of patients, as well as symptoms of anosognosia or aggravation.

Abstract WP131: A Proposed Weighted-ASPECTS Based on the NIH Stroke Scale

The Alberta Stroke Program Early CT score (ASPECTS) is a 10-item score of the territory of the middle cerebral artery (MCA). Helpful in defining the extent of ischemia, prognosis, and neurological severity, the role of each item in the score is not clear in the literature. Variables such as age, cerebral hemisphere, vascular occlusion, and collateral status seem to influence the role of each item in terms of neurological severity measured by the NIH Stroke Scale (NIHSS). Recognizing the clinical role of these items can be useful for accurately measuring the clinical-radiological mismatch and maybe allow for expanded therapeutic windows in stroke. We aim to identify the correlation of each ASPECTS item with neurological severity. In an ambispective analysis, patients with ischemic Stroke from a national network of hospitals were included. We conducted a linear regression model, with the NIHSS scores at admission serving as the dependent variable. Models were adjusted for age, time from stroke symptom onset and hemisphere involvement. We excluded patients with an ASPECTS of 10 and those without an arterial-CT brain scan at admission. In total, 587 patients from 32 hospitals were included in the final analysis. Males represented 39.5% of the sample, with a mean age of 68 (±16) years. The median NIHSS score was 11 [5, 17], and the median ASPECTS was 8 [6, 9]. Among patients without occlusion of MCA 1, 2, and 3 (n=352), factors significantly associated with NIHSS scores included age (beta-coefficient 0.08), time from stroke onset (-0.001), left hemisphere (1.58), and ASPECTS subitems M1 (4.7), M3 (2.5), M4 (1.9), M5 (1.8), Insula (1.7), and Lentiform (2.8). In patients with proximal occlusion (n=235), factors significantly associated with NIHSS scores were age (0.07), left hemisphere (4.1), ASPECTS subitems M6 (2.4) and Lentiform (2.4), MCA 1 occlusion (3.3), and absent collateral status (5.8). Our results confirm the different roles of each ASPECTS item on neurological severity in acute stroke patients. Adjusted equations with confidence intervals were created to predict the NIHSS score. Our results bring to the literature an innovative tool for numerically assessing the clinical-radiological mismatch using a simple and accessible neuroimaging method.