Early Morbidities of Hypoxia-Ischemic Encephalopathy in Term Neonates With a Resistive Index as a Prognostic Indicator.

Background Acidosis, hypoxemia, and hypercarbia are symptoms of a syndrome known as perinatal asphyxia that occurs during the first and second stages of labor and shortly after delivery due to poor gas exchange. The Doppler technique is a non-invasive way to assess the risk of neurodevelopment damage in hypoxic-ischemic encephalopathy (HIE) that may be done at the patient's bedside without disturbing them. The study aims to evaluate cranial ultrasound findings in HIE and investigate the role of resistive index (RI) values assessed by color Doppler transcranial ultrasonography in predicting early morbidities in neonates with HIE within 72 hours of life. Methodology Prospective observational research was carried out at the north Karnataka region's tertiary newborn critical care unit. The study included 54 infants with HIE in total. The male-to-female ratio was 1.7:1, with 34 (63%) male and 20 (37%) female newborns. Results About 32 instances had grade I HIE, 8 had grade II HIE, and 14 had grade III HIE. In 35 instances (64.81%), the RI was normal; in 19 cases (35.19%), it was abnormal. Increased periventricular density and cerebral parenchyma echo density were common Doppler ultrasonography findings. Roughly 93% of people survived, and 7% of people died from HIE. Seizures (12.96%) and acute renal damage (33.33%) were the most frequent consequences. Conclusion In instances of HIE, the RI was revealed to be a favorable predictive indicator for newborn prognosis. Counseling and educating parents about early morbidities, anticipated long-term consequences, and the need for follow-up will all benefit from it. Additionally, color Doppler is a practical and secure diagnostic method for determining a newborn's level of HIE.

Latest research in nootropic therapy of patients with chronic cerebral circulation insufficiency.

OBJECTIVE: Aim: To analyze latest research on the usage of choline alfoscerate and ethylmethylhydroxypyridine succinate (EMHPS) as nootropic therapy for patients with chronic cerebral circulation insufficiency (CCCI). PATIENTS AND METHODS: Materials and Methods: Bibliosemantic, comparative and system analysis methods were used in the study. The proposed recommendations are developed on the basis of the analysis of modern literature, the results of randomized studies and meta-analyses, authoritative studies devoted to the study of the CCCI problem. CONCLUSION: Conclusions: The combination of EMHPS with choline alfoscerate for the complex treatment of CCCI and associated syndromes improves the functions of the endothelium, leads to asthenic syndrome, indicators of stress, depression and anxiety decreasing has a positive effect on the cognitive impairment and complications' progress reduction.

The Association Between the Location of Subarachnoid Hemorrhage and the Occurrence of Takotsubo Cardiomyopathy: A Systematic Review and Meta-analysis.

Takotsubo cardiomyopathy (TCM) is a syndrome characterized by transient regional cardiac dysfunction of the left ventricle. The goal of this review is to better understand the relationship between the anatomic locations of subarachnoid hemorrhages (SAHs) and the development of TCM as identified through a review of cohort studies. From inception to December 2023, we systematically explored major electronic medical information sources to identify cases of TCM that developed after SAHs. The six selected studies included in the meta-analysis suggest a modest but statistically significant increase in the odds of the events in the posterior circulation group compared to the anterior circulation group, with a combined odds ratio (OR) estimate of around 1.45-1.46. The fixed effect model gives an overall OR of 1.45 with a 95% confidence interval (CI) of 1.01 to 2.10, z = 2.01, p = 0.0442, while the random effects model yields a slightly higher OR of 1.46 with the same 95% CI, z = 2.03, p = 0.0425. There is a tendency for SAH occurrence in the posterior cerebral circulation to cause SAH-related TCM more frequently than in the anterior cerebral circulation.

Role of the vessel morphology on the lenticulostriate arteries hemodynamics during atrial fibrillation: A CFD-based multivariate regression analysis.

BACKGROUND AND OBJECTIVE: Atrial fibrillation (AF) is the most common cardiac arrhythmia, inducing accelerated and irregular beating. Beside well-known disabling symptoms - such as palpitations, reduced exercise tolerance, and chest discomfort - there is growing evidence that an alteration of deep cerebral hemodynamics due to AF increases the risk of vascular dementia and cognitive impairment, even in the absence of clinical strokes. The alteration of deep cerebral circulation in AF represents one of the least investigated among the possible mechanisms. Lenticulostriate arteries (LSAs) are small perforating arteries mainly departing from the middle cerebral artery (MCA) and susceptible to small vessel disease, which is one of the mechanisms of subcortical vascular dementia development. The purpose of this study is to investigate the impact of different LSAs morphologies on the cerebral hemodynamics during AF. METHODS: By combining a computational fluid dynamics (CFD) analysis of LSAs with 7T high-resolution magnetic resonance imaging (MRI), we performed different CFD-based multivariate regression analyses to detect which geometrical and morphological vessel features mostly affect AF hemodynamics in terms of wall shear stress. We exploited 17 cerebral 7T-MRI derived LSA vascular geometries extracted from 10 subjects and internal carotid artery data from validated 0D cardiovascular-cerebral modeling as inflow conditions. RESULTS: Our results revealed that few geometrical variables - namely the size of the MCA and the bifurcation angles between MCA and LSA - are able to satisfactorily predict the AF impact. In particular, the present study indicates that LSA morphologies exhibiting markedly obtuse LSA-MCA inlet angles and small MCA size downstream of the LSA-MCA bifurcation may be more prone to vascular damage induced by AF. CONCLUSIONS: The present MRI-based computational study has been able for the first time to: (i) investigate the net impact of LSAs vascular morphologies on cerebral hemodynamics during AF events; (ii) detect which combination of morphological features worsens the hemodynamic response in the presence of AF. Awaiting necessary clinical confirmation, our analysis suggests that the local hemodynamics of LSAs is affected by their geometrical features and some LSA morphologies undergo greater hemodynamic alterations in the presence of AF.

Linking peripheral atherosclerosis to blood-brain barrier disruption: elucidating its role as a manifestation of cerebral small vessel disease in vascular cognitive impairment.

Aging plays a pivotal role in the pathogenesis of cerebral small vessel disease (CSVD), contributing to the onset and progression of vascular cognitive impairment and dementia (VCID). In older adults, CSVD often leads to significant pathological outcomes, including blood-brain barrier (BBB) disruption, which in turn triggers neuroinflammation and white matter damage. This damage is frequently observed as white matter hyperintensities (WMHs) in neuroimaging studies. There is mounting evidence that older adults with atherosclerotic vascular diseases, such as peripheral artery disease, ischemic heart disease, and carotid artery stenosis, face a heightened risk of developing CSVD and VCID. This review explores the complex relationship between peripheral atherosclerosis, the pathogenesis of CSVD, and BBB disruption. It explores the continuum of vascular aging, emphasizing the shared pathomechanisms that underlie atherosclerosis in large arteries and BBB disruption in the cerebral microcirculation, exacerbating both CSVD and VCID. By reviewing current evidence, this paper discusses the impact of endothelial dysfunction, cellular senescence, inflammation, and oxidative stress on vascular and neurovascular health. This review aims to enhance understanding of these complex interactions and advocate for integrated approaches to manage vascular health, thereby mitigating the risk and progression of CSVD and VCID.

Cerebral venous congestion alters CNS homeostatic plasticity, evoking tinnitus-like behavior.

BACKGROUND: Brain function and neuronal activity depend on a constant supply of blood from the cerebral circulation. The cerebral venous system (CVS) contains approximately 70% of the total cerebral blood volume; similar to the cerebral arterial system, the CVS plays a prominent role in the maintenance of central nervous system (CNS) homeostasis. Impaired venous autoregulation, which can appear in forms such as cerebral venous congestion, may lead to metabolic abnormalities in the brain, causing severe cerebral functional defects and even chronic tinnitus. However, the role of cerebral venous congestion in the progression of tinnitus is underrecognized, and its pathophysiology is still incompletely understood. This study elucidated the specific pathogenetic role of cerebral venous congestion in the onset and persistence of tinnitus and the possible neurophysiological mechanisms. RESULTS: We found that a rat model of cerebral venous congestion exhibited tinnitus-like behavioral manifestations at 14 days postoperatively; from that point onward, they showed signs of persistent tinnitus without significant hearing impairment. Subsequent neuroimaging and neurochemical findings showed CNS homeostatic plasticity disturbance in rats with cerebral venous congestion, reflected in increased neural metabolic activity, ultrastructural synaptic changes, upregulated synaptic efficacy, reduced inhibitory synaptic transmission (due to GABA deficiency), and elevated expression of neuroplasticity-related proteins in central auditory and extra-auditory pathways. CONCLUSION: Collectively, our data suggest that alternations in CNS homeostatic plasticity may play a vital role in tinnitus pathology caused by cerebral venous congestion. These findings provide a new perspective on tinnitus related to cerebral venous congestion and may facilitate the development of precise interventions to interrupt its pathogenesis.

Validating the accuracy of real-time phase-contrast MRI and quantifying the effects of free breathing on cerebrospinal fluid dynamics.

BACKGROUND: Understanding of the cerebrospinal fluid (CSF) circulation is essential for physiological studies and clinical diagnosis. Real-time phase contrast sequences (RT-PC) can quantify beat-to-beat CSF flow signals. However, the detailed effects of free-breathing on CSF parameters are not fully understood. This study aims to validate RT-PC's accuracy by comparing it with the conventional phase-contrast sequence (CINE-PC) and quantify the effect of free-breathing on CSF parameters at the intracranial and extracranial levels using a time-domain multiparametric analysis method. METHODS: Thirty-six healthy participants underwent MRI in a 3T scanner for CSF oscillations quantification at the cervical spine (C2-C3) and Sylvian aqueduct, using CINE-PC and RT-PC. CINE-PC uses 32 velocity maps to represent dynamic CSF flow over an average cardiac cycle, while RT-PC continuously quantifies CSF flow over 45-seconds. Free-breathing signals were recorded from 25 participants. RT-PC signal was segmented into independent cardiac cycle flow curves (Qt) and reconstructed into an averaged Qt. To assess RT-PC's accuracy, parameters such as segmented area, flow amplitude, and stroke volume (SV) of the reconstructed Qt from RT-PC were compared with those derived from the averaged Qt generated by CINE-PC. The breathing signal was used to categorize the Qt into expiratory or inspiratory phases, enabling the reconstruction of two Qt for inspiration and expiration. The breathing effects on various CSF parameters can be quantified by comparing these two reconstructed Qt. RESULTS: RT-PC overestimated CSF area (82.7% at aqueduct, 11.5% at C2-C3) compared to CINE-PC. Stroke volumes for CINE-PC were 615 mm³ (aqueduct) and 43 mm³ (spinal), and 581 mm³ (aqueduct) and 46 mm³ (spinal) for RT-PC. During thoracic pressure increase, spinal CSF net flow, flow amplitude, SV, and cardiac period increased by 6.3%, 6.8%, 14%, and 6%, respectively. Breathing effects on net flow showed a significant phase difference compared to the other parameters. Aqueduct-CSF flows were more affected by breathing than spinal-CSF. CONCLUSIONS: RT-PC accurately quantifies CSF oscillations in real-time and eliminates the need for cardiac synchronization, enabling the quantification of the cardiac and breathing components of CSF flow. This study quantifies the impact of free-breathing on CSF parameters, offering valuable physiological references for understanding the effects of breathing on CSF dynamics.

Immunological Profile and Markers of Endothelial Dysfunction in Elderly Patients with Cognitive Impairments.

The process of aging is accompanied by a dynamic restructuring of the immune response, a phenomenon known as immunosenescence. Further, damage to the endothelium can be both a cause and a consequence of many diseases, especially in elderly people. The purpose of this study was to carry out immunological and biochemical profiling of elderly people with acute ischemic stroke (AIS), chronic cerebral circulation insufficiency (CCCI), prediabetes or newly diagnosed type II diabetes mellitus (DM), and subcortical ischemic vascular dementia (SIVD). Socio-demographic, lifestyle, and cognitive data were obtained. Biochemical, hematological, and immunological analyses were carried out, and extracellular vesicles (EVs) with endothelial CD markers were assessed. The greatest number of significant deviations from conditionally healthy donors (HDs) of the same age were registered in the SIVD group, a total of 20, of which 12 were specific and six were non-specific but with maximal differences (as compared to the other three groups) from the HDs group. The non-specific deviations were for the MOCA (Montreal Cognitive Impairment Scale), the MMSE (Mini Mental State Examination) and life satisfaction self-assessment scores, a decrease of albumin levels, and ADAMTS13 (a Disintegrin and Metalloproteinase with a Thrombospondin Type 1 motif, member 13) activity, and an increase of the VWF (von Willebrand factor) level. Considering the significant changes in immunological parameters (mostly Th17-like cells) and endothelial CD markers (CD144 and CD34), vascular repair was impaired to the greatest extent in the DM group. The AIS patients showed 12 significant deviations from the HD controls, including three specific to this group. These were high NEFAs (non-esterified fatty acids) and CD31 and CD147 markers of EVs. The lowest number of deviations were registered in the CCCI group, nine in total. There were significant changes from the HD controls with no specifics to this group, and just one non-specific with a maximal difference from the control parameters, which was α1-AGP (alpha 1 acid glycoprotein, orosomucoid). Besides the DM patients, impairments of vascular repair were also registered in the CCCI and AIS patients, with a complete absence of such in patients with dementia (SIVD group). On the other hand, microvascular damage seemed to be maximal in the latter group, considering the biochemical indicators VWF and ADAMTS13. In the DM patients, a maximum immune response was registered, mainly with Th17-like cells. In the CCCI group, the reaction was not as pronounced compared to other groups of patients, which may indicate the initial stages and/or compensatory nature of organic changes (remodeling). At the same time, immunological and biochemical deviations in SIVD patients indicated a persistent remodeling in microvessels, chronic inflammation, and a significant decrease in the anabolic function of the liver and other tissues. The data obtained support two interrelated assumptions. Taking into account the primary biochemical factors that trigger the pathological processes associated with vascular pathology and related diseases, the first assumption is that purine degradation in skeletal muscle may be a major factor in the production of uric acid, followed by its production by non-muscle cells, the main of which are endothelial cells. Another assumption is that therapeutic factors that increase the levels of endothelial progenitor cells may have a therapeutic effect in reducing the risk of cerebrovascular disease and related neurodegenerative diseases.

Basilar tip fenestration giving rise to Percheron's and mesencephalic arteries.

The basilar bifurcation region is a common site for intracranial aneurysms, as well as it gives rise to a group of perforating arteries that supply the mesencephalon and the thalamus. Complex vascular microanatomy poses a diagnostic and therapeutic challenge for neurosurgeons, neuroradiologists and neurologists. In this paper, we present a previously unreported case of basilar tip fenestration that gave rise to five perforating arteries: the artery of Percheron and four mesencephalic arteries. Due to invaluable clinical significance, the possibility of such a variant must be considered during performing various neurovascular procedures, since e.g., embolization of the fenestration misdiagnosed as an aneurysm would inevitably lead to severe neurological complications (consciousness disturbances, quadriplegia, and sensory loss). Comprehensive knowledge of the neuroanatomy and neuroembryology is crucial to safe execution of intracranial interventions.

A novel parameter for the prediction of rupture risk of cerebral aneurysms based on morphology.

Neurosurgeons often encounter dilemmas in the clinical management of cerebral aneurysms owing to an uncertainty of their rupture status and rupture risk. This study evaluates the influence of natural frequency of an aneurysm, as a novel morphological parameter to understand and analyze rupture status and risk prediction. In this work, we employ the natural frequency of 20 idealized and 50 patient specific aneurysms. The natural frequency of patient specific aneurysms is then compared against their rupture status. A strong correlation was observed between various morphological indicators and natural frequency for ideal and patient specific geometries. A statistical analysis with both Mann Whitney U test and T-test for rupture status against natural frequency has given a p-value less than 0.01 indicating a strong correlation between them. The correlation of morphological parameters with natural frequency from Pearson correlation coefficient and T-test suggests a holistic reflection of their effects on the natural frequency of an aneurysm. Thus, natural frequency could be a good indicator to discern the rupture potential of an aneurysm. The correlation between rupture status and natural frequency makes it a novel parameter that can differentiate between ruptured and unruptured patient specific aneurysms.

Improving multidisciplinary hospital care for acute cerebral circulation disorders in Kazakhstan.

Background: According to the World Stroke Organization, there was a significant increase in stroke cases, stroke deaths, and the DALY rate in low- and middle-income countries in 2022. The number of stroke cases rose by 70.0%, stroke deaths reached 86.0%, and the DALY rate reached 89.0%. Among cerebrovascular diseases, ischemic stroke accounts for 62.0% of all strokes, with more than 7.6 million cases reported annually.Kazakhstan, with a population of 19,832,737, is the largest country in Central Asia in terms of territory. In Kazakhstan, the incidence of cerebrovascular disease has risen from 258.4 cases per 100,000 population in 2015 to 433.7 cases per 100,000 population in 2020. Official statistics indicate that the average inpatient mortality rate from stroke in the country is 16.2%, and the average time for patients to be delivered to the hospital after an ambulance call is 40 min (83.2%).Our study findings reveal that in the regions of Kazakhstan, the main contributors to the high morbidity and mortality rates in stroke are a shortage of doctors, inadequate primary healthcare, insufficient follow-up and treatment, and delayed hospitalization. Consequently, this study has helped fill knowledge gaps regarding the epidemiological situation in these regions and underscores the need for training doctors in managing high-risk patients, establishing multidisciplinary home visit teams, and establishing "Stroke Schools" to enhance public awareness of early stroke signs and the fundamentals of a healthy lifestyle. Future research endeavors should consider these study results as valuable contributions towards addressing the existing problems. Aim: To study the prevalence and mortality of acute cerebral circulation impairment in the population within multidisciplinary hospitals in the cities of Nur-Sultan and Almaty, Republic of Kazakhstan, for the period of 2018-2020.This retrospective study was conducted in two stages. In the first stage, an analysis of morbidity, prevalence, and mortality was conducted for the population of Nur-Sultan and Almaty cities, as well as for the overall population of Kazakhstan. This analysis was based on data from the "Electronic Register of Discharged Patients" (IS ERDB) and the annual collection "Health of the Population of the Republic of Kazakhstan and the Activities of Health Organizations in 2015-2020". In the second stage, we examined the care provided to patients with acute impaired cerebral circulation in a multidisciplinary hospital in these two cities. The analysis was based on data regarding the sex and age composition of treated patients in hospitals across the Republic of Kazakhstan, categorized according to the ICD-10 code "Acute Impaired Cerebral Circulation" (I60-I64). We investigated the methods of patients' delivery to medical organizations, types of hospitalization, and outcomes of treated patients. The sample of patients was selected using data from the "Electronic Register of Dispensary Patients" of the Ministry of Health of the Republic of Kazakhstan, along with the statistical collection "Health of the Population of the Republic of Kazakhstan and the Activities of Healthcare Organizations". Between January 1, 2018, and December 31, 2020, a total of 5965 patients were diagnosed with a cerebrovascular event and admitted to a general hospital in Nur-Sultan city, while 13,498 patients were diagnosed and admitted in Almaty city.

MINE-BLAST TRAUMA AS A FACTOR IN THE EARLY DEVELOPMENT OF VASCULAR DISEASES OF THE BRAIN.

OBJECTIVE: The aim of this study is to investigate the state of bulbar conjunctival vessels, rheological properties of blood, catecholamines (adrenaline, norepinephrine), lipid metabolism, alkaline proteins of blood serum in patients with consequences of mild combat traumatic brain injury. PATIENTS AND METHODS: Materials and methods: 76 individuals aged 28 to 41 years were examined. The duration of the injury lasted from 2 to 4 years. The control group consisted of 28 individuals aged 45 to 49 years with primary cerebral atherosclerosis and manifestations of cerebral circulation disorders. The state of the bulbar conjunctiva vessels and blood circulation was studied using a slit lamp SHCHL-2B at 40-fold magnification. Rheological parameters, lipid metabolism, serum alkaline proteins, total catecholamines were studied according to generally accepted methods. RESULTS: Results: Changes in the vessels of the bulbar conjunctiva (stage II-III) were detected in 76% of the subjects, indicating the formation of cerebral vascular pathology, and in 87% of patients with initial cerebral atherosclerosis. The analysis of lipid metabolism showed significantly (p<0.05) increased data on all studied parameters (cholesterol, high-density lipoprotein, ß-lipoprotein, atherogenic index), both in patients with aftereffects of mild combat traumatic brain injury and in patients with initial cerebral atherosclerosis. An increase in alkaline proteins indices we detected in 62% of patients with aftereffects of mild combat cerebral trauma and in 55% of patients with initial cerebral atherosclerosis. At the same time, there was an increase in total catecholamines in the erythrocytes of patients with combat head injury. An increase in fibrinogen was noted in both groups, but in the group with initial cerebral atherosclerosis it was more pronounced. CONCLUSION: Conclusions: Combat traumatic brain injury contributes to the early formation of cerebral atherosclerosis and cerebral circulation disorders in this category of patients. The examination methods we have studied should be included in the survey plan for these patients. They are important not only for diagnosis, but also for improving treatment and preventing vascular disasters.

Cerebral venous congestion alters brain metabolite profiles, impairing cognitive function.

Vascular cognitive impairment (VCI) represents the second most common cause of dementia after Alzheimer's disease, and pathological changes in cerebral vascular structure and function are pivotal causes of VCI. Cognitive impairment caused by arterial ischemia has been extensively studied the whole time; the influence of cerebral venous congestion on cognitive impairment draws doctors' attention in recent clinical practice, but the underlying neuropathophysiological alterations are not completely understood. This study elucidated the specific pathogenetic role of cerebral venous congestion in cognitive-behavioral deterioration and possible electrophysiological mechanisms. Using cerebral venous congestion rat models, we found these rats exhibited decreased long-term potentiation (LTP) in the hippocampal dentate gyrus and impaired spatial learning and memory. Based on untargeted metabolomics, N-acetyl-L-cysteine (NAC) deficiency was detected in cerebral venous congestion rats; supplementation with NAC appeared to ameliorate synaptic deficits, rescue impaired LTP, and mitigate cognitive impairment. In a cohort of cerebral venous congestion patients, NAC levels were decreased; NAC concentration was negatively correlated with subjective cognitive decline (SCD) score but positively correlated with mini-mental state examination (MMSE) score. These findings provide a new perspective on cognitive impairment and support further exploration of NAC as a therapeutic target for the prevention and treatment of VCI.

Associations between cognitive impairment and computed tomography perfusion in different lobes in acute stroke of the anterior circulation / Associações entre déficit cognitivo e perfusão de tomografia computadorizada em diferentes lobos no AVC agudo da circulação anterior

Abstract Background Cognitive impairment (CI) during the acute phase of stroke should not be ignored. The present study analyzed the relationship between computed tomography perfusion (CTP) in different lobes and CI during the acute phase of stroke in patients with cerebral infarction. Methods The present study included 125 subjects: 96 in the acute phase of stroke and 29 elderly healthy subjects as a control group. The Montreal Cognitive Assessment (MoCA) was used to evaluate the cognitive status of the two groups. The CTP scans include four parameters: cerebral blood flow (CBF), cerebral blood volume (CBV), time to peak (TTP), and mean transit time (MTT). Results The MoCA scores for naming, language and delayed recall significantly decreased only in patients with left cerebral infarctions. The MTT of the left vessels in the occipital lobe and the CBF of the right vessels in the frontal lobe were negatively related to the MoCA scores of patients with left infarction. The CBV of the left vessels in the frontal lobe and the CBF of left vessels in the parietal lobe were positively linked to the MoCA scores of patients with left infarction. The CBF of the right vessels in the temporal lobe was positively related to the MoCA scores of patients with right infarction. Finally, the CBF of the left vessels in the temporal lobe was inversely correlated with the MoCA scores of patients with right infarctions. Conclusion During the acute phase of stroke, CTP was closely associated with CI. Changed CTP could be a potential neuroimaging biomarker to predict CI during the acute phase of stroke.

Resumo Antecedentes O comprometimento cognitivo (CC) durante a fase aguda do acidente vascular cerebral (AVC) não deve ser ignorado. O presente estudo analisou a relação entre perfusão por tomografia computadorizada (PTC) em diferentes lobos e CC durante a fase aguda do AVC em pacientes com infarto cerebral. Métodos O presente estudo incluiu 125 indivíduos: 96 na fase aguda do AVC e 29 idosos saudáveis como grupo controle. O Montreal Cognitive Assessment (MoCA) foi usado para avaliar o estado cognitivo dos dois grupos. Os exames de PCT incluem quatro parâmetros: fluxo sanguíneo cerebral (FSC), volume sanguíneo cerebral (VSC), tempo até o pico (TAP) e tempo médio de trânsito (TMT). Resultados Os escores do MoCA para nomeação, linguagem e recordação tardia diminuíram significativamente apenas em pacientes com infarto cerebral esquerdo. O TMT dos vasos esquerdos no lobo occipital e o FSC dos vasos direitos no lobo frontal foram negativamente relacionados aos escores MoCA de pacientes com infarto esquerdo. A VSC dos vasos esquerdos em o lobo frontal e o FSC dos vasos esquerdos no lobo parietal foram positivamente ligados aos escores MoCA de pacientes com infarto esquerdo. O FSC dos vasos direitos no lobo temporal foi positivamente relacionado com os escores MoCA de pacientes com infarto direito. Finalmente, o FSC dos vasos esquerdos no lobo temporal foi inversamente correlacionado com os escores MoCA de pacientes com infartos direitos. Conclusão Durante a fase aguda do AVC, a PCT esteve intimamente associada ao CC. O PCT alterado pode ser um potencial biomarcador de neuroimagem para prever CC durante a fase aguda do AVC.

The impact of collateral status on cerebral vasospasm and delayed cerebral ischemia in subarachnoid hemorrhage.

OBJECTIVE: Cerebral collateral circulation may affect subarachnoid hemorrhage (SAH) induced cerebral vasospasm and delayed cerebral ischemia. In this study our aim was to investigate the relationship between collateral status, vasospasm and delayed cerebral ischemia (DCI) in both aneurysmal and nonaneurysmal SAH. METHODS: Patients diagnosed as SAH with and without aneurysm were included and their data investigated retrospectively. After the patients diagnosed as SAH according to cerebral computed tomography (CT)/magnetic resonance imaging (MRI), they underwent cerebral angiography to check for cerebral aneurysm. The diagnosis of DCI was made according to the neurological examination and control CT/MRI. All the patients had their control cerebral angiography on days 7 to 10 in order to assess vasospasm and also collateral circulation. The American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology (ASITN/SIR) Collateral Flow Grading System was modified to measure collateral circulation. RESULTS: A total of 59 patients data were analyzed. Patients with aneurysmal SAH had higher Fisher scores and DCI was more common. Although there was no statistically significant difference between the patients with and without DCI in terms of demographics and mortality, patients with DCI had worse collateral circulation and more severe vasospasm. These patients had higher Fisher scores and more cerebral aneurysm overall. CONCLUSIONS: According to our data, patients with higher Fisher scores, more severe vasospasm, and poor cerebral collateral circulation may experience DCI more frequently. Additionally aneurysmal SAH had higher Fisher scores and DCI was seen more common. To improve the clinical results for SAH patients, we believe that physicians should be aware of the DCI risk factors.

Cerebral Circulation and Brain Temperature during an Ultra-Short Session of Dry Immersion in Young Subjects.

The primary aim of the study was to assess cerebral circulation in healthy young subjects during an ultra-short (45 min) session of ground-based microgravity modeled by "dry" immersion (DI), with the help of a multifunctional Laser Doppler Flowmetry (LDF) analyzer. In addition, we tested a hypothesis that cerebral temperature would grow during a DI session. The supraorbital area of the forehead and forearm area were tested before, within, and after a DI session. Average perfusion, five oscillation ranges of the LDF spectrum, and brain temperature were assessed. Within a DI session, in the supraorbital area most of LDF parameters remained unchanged except for a 30% increase in respiratory associated (venular) rhythm. The temperature of the supraorbital area increased by up to 38.5 °C within the DI session. In the forearm area, the average value of perfusion and its nutritive component increased, presumably due to thermoregulation. In conclusion, the results suggest that a 45 min DI session does not exert a substantial effect on cerebral blood perfusion and systemic hemodynamics in young healthy subjects. Moderate signs of venous stasis were observed, and brain temperature increased during a DI session. These findings must be thoroughly validated in future studies because elevated brain temperature during a DI session can contribute to some reactions to DI.

Extracranial-intracranial bypass surgery for intracranial aneurysm of the anterior cerebral circulation: A systematic review and meta-analysis.

Background: The safety of extracranial-intracranial (EC-IC) bypass in the management of anterior circulation intracranial aneurysms (IAs) remains to be determined. This systematic review aims to summarize the existing evidence and provide guidance for the precise management of IAs. Data source: We constructed search strategies and comprehensively searched Pubmed, Medline, Embase, Web of science, and Cochrane library. Methods: This systematic review was actualized according to the PRISMA statement. We evaluated study quality using the methodological index for non-randomized study (MINORS). Effect sizes were pooled using a random-effects model. Heterogeneity between studies was assessed using the I 2 test. Publication bias was assessed using the Egger's test. The registration number for this systematic review is CRD42023396730. Result: This systematic review included a total of 21 articles, involving 915 patients. Postoperative bypass patency rate was 99% (95% CI 0.98-1.00); short-term follow-up was 98% (95% CI 0.94-1.00); long-term follow-up was 95% (95% CI 0.93-0.97). The long-term follow-up occlusion rate of saphenous vein was higher than that of radial artery (OR 6.10 95% CI 1.04-35.59). Short-term surgery-related mortality was 0.3% (95% CI 0.000-0.012); long-term follow-up was 0.4% (95% CI 0.000-0.013); The proportion of patients with a score of 0-2 on the modified Rankin Scale (mRS) during long-term follow-up was 92% (95% CI 0.86-0.98). The incidence rates of long-term follow-up complications were: ischemic 3% (95% CI 0.01-0.06); hemorrhagic 1% (95% CI 0.00-0.03); neurological deficit 1% (95% CI 0.00-0.03); other 3% (95% CI 0.01-0.06). Limitation: Most of the included studies were retrospective studies. Studies reporting preoperative status were not sufficient to demonstrate postoperative improvement. Lack of sufficient subgroup information such as aneurysm rupture status. Conclusion: EC-IC therapy for anterior circulation IAs has a high safety profile. Higher level of evidence is still needed to support clinical decision. Systematic review registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023396730, identifier: CRD42023396730.

Perioperative cerebral perfusion in aortic arch surgery: a potential link with neurological outcome.

OBJECTIVES: The aim of this study was to examine whether perioperative changes in cerebral blood flow (CBF) relate to postoperative neurological deficits in patients undergoing aortic arch surgery involving antegrade selective cerebral perfusion (ASCP). METHODS: We retrospectively analysed data from patients who underwent aortic arch surgery involving ASCP and perioperative transcranial Doppler assessments. Linear mixed-model analyses were performed to examine perioperative changes in mean bilateral blood velocity in the middle cerebral arteries, reflecting changes in CBF, and their relation with neurological deficits, i.e. ischaemic stroke and/or delirium. Logistic regression analyses were performed to explore possible risk factors for postoperative neurological deficits. RESULTS: In our study population (N = 102), intraoperative blood velocities were lower compared to preoperative levels, and lowest during ASCP. Thirty-six (35%) patients with postoperative neurological deficits (ischaemic stroke, n = 9; delirium, n = 25; both, n = 2) had lower blood velocity during ASCP compared to patients without (25.4 vs 37.0 cm/s; P = 0.002). Logistic regression analyses revealed lower blood velocity during ASCP as an independent risk factor for postoperative neurological deficits (odds ratio = 0.959; 95% confidence interval: 0.923, 0.997; P = 0.037). CONCLUSIONS: Lower intraoperative CBF during ASCP seems independently related to postoperative neurological deficits in patients undergoing aortic arch surgery. Because CBF is a modifiable factor during ASCP, our observation has significant potential to improve clinical management and prevent neurological deficits.

Effect of Chronically Suppressed Plasma Angiotensin II on Regulation of the CYP4A/20-HETE Pathway in the Dahl Salt-Sensitive Rat.

In Dahl salt-sensitive (SS) rats, impaired vascular relaxation can be restored by: (1) minipump infusion of a low (sub-pressor) dose of angiotensin II (ANG II) to restore physiological levels of plasma ANG II, (2) inhibition of 20-HETE production, and (3) introgression of a normally functioning renin allele from the Brown Norway rat (SS-13BN consomic rat). Unlike SS rats, SS-13BN rats have normal levels of ANG II on a normal-salt diet and suppressed ANG II on a high-salt (HS) diet. This study tested whether chronically low ANG II levels in SS rats upregulate cytochrome P450-4A (CYP4A) increasing the production of the vasoconstrictor 20-HETE. Although salt-induced suppression of ANG II levels increased reactive oxygen species (ROS) in basilar arteries from SS-13BN rats in previous studies, this study showed no change in vascular 20-HETE levels in response to ANGII suppression. CYP4A inhibition significantly reduced vascular ROS levels and restored endothelium-dependent relaxation in response to acetylcholine in the middle cerebral artery (MCA) of SS rats and HS-fed SS-13BN rats. These data demonstrate that both the renin-angiotensin system and the CYP4A/20-HETE pathway play a direct role in the vascular dysfunction of the Dahl SS rat but are independent of each other, even though they may both contribute to vascular dysfunction through ROS production.

Impacts of respiratory fluctuations on cerebral circulation: a machine-learning-integrated 0-1D multiscale hemodynamic model.

Objective. This study aims to accurately identify the effects of respiration on the hemodynamics of the human cardiovascular system, especially the cerebral circulation.Approach: we have developed a machine learning (ML)-integrated zero-one-dimensional (0-1D) multiscale hemodynamic model combining a lumped-parameter 0D model for the peripheral vascular bed and a one-dimensional (1D) hemodynamic model for the vascular network.In vivomeasurement data of 21 patients were retrieved and partitioned into 8000 data samples in which respiratory fluctuation (RF) of intrathoracic pressure (ITP) was fitted by the Fourier series. ML-based classification and regression algorithms were used to examine the influencing factors and variation trends of the key parameters in the ITP equations and the mean arterial pressure. These parameters were employed as the initial conditions of the 0-1D model to calculate the radial artery blood pressure and the vertebral artery blood flow volume (VAFV).Main results: during stable spontaneous respiration, the VAFV can be augmented at the inhalation endpoints by approximately 0.1 ml s-1for infants and 0.5 ml s-1for adolescents or adults, compared to those without RF effects. It is verified that deep respiration can further increase the ranges up to 0.25 ml s-1and 1 ml s-1, respectively.Significance. This study reveals that reasonable adjustment of respiratory patterns, i.e. in deep breathing, enhances the VAFV and promotes cerebral circulation.