Progressing haemorrhagic stroke: categories, causes, mechanisms and managements

Brain Targeting Nanomedicines: Pitfalls and Promise

Brain diseases are the most devastating problem among the world's increasingly aging population, and the number of patients with neurological diseases is expected to increase in the future. Although methods for delivering drugs to the brain have advanced significantly, none of these approaches provide satisfactory results for the treatment of brain diseases. This remains a challenge due to the unique anatomy and physiology of the brain, including tight regulation and limited access of substances across the blood-brain barrier. Nanoparticles are considered an ideal drug delivery system to hard-to-reach organs such as the brain. The development of new drugs and new nanomaterial-based brain treatments has opened various opportunities for scientists to develop brain-specific delivery systems that could improve treatment outcomes for patients with brain disorders such as Alzheimer's disease, Parkinson's disease, stroke and brain tumors. In this review, we discuss noteworthy literature that examines recent developments in brain-targeted nanomedicines used in the treatment of neurological diseases.

Remote ischemic conditioning after stroke: Research progress in clinical study

BACKGROUND AND PURPOSE

Stroke is a leading cause of global morbidity and mortality, indicating the necessity and urgency of effective prevention and treatment. Remote ischemic conditioning (RIC) is a convenient, simple, non-intrusive, and effective method that can be easily added to the treatment regime of stroke patients. Animal experiments and clinical trials have proved the neuroprotective effects of RIC on brain injury including (examples of neuroprotective effects). This neuroprotection is achieved by raising brain tolerance to ischemia, increasing local cerebral blood perfusion, promoting collateral circulations, neural regeneration, and reducing the incidence of hematomas in brain tissue. This current paper will summarize the studies within the last 2 years for the comprehensive understanding of the use of RIC in the treatment of stroke.

METHODS

This paper summarizes the clinical research progress of RIC on stroke (ischemic stroke and hemorrhagic stroke (HS)). This paper is a systematic review of research published on registered clinical trials using RIC in stroke from inception through November 2022. Four major databases (PUBMED, WEB OF SCIENCE, EMBASE, and ClinicalTrials.gov) were searched.

RESULTS

Forty-eight studies were identified meeting our criteria. Of these studies, 14 were in patients with acute ischemic stroke with onset times ranging from 6 h to 14 days, seven were in patients with intravenous thrombolysis or endovascular thrombectomy, 10 were in patients with intracranial atherosclerotic stenosis, six on patients with vascular cognitive impairment, three on patients with moyamoya disease, and eight on patients with HS. Of the 48 studies, 42 were completed and six are ongoing.

CONCLUSIONS

RIC is safe, feasible, and effective in the treatment of stroke. Large-scale research is still required to explore the optimal treatment options and mechanisms of RIC in the future to develop a breakthrough in stroke prevention and treatment.

mcTFI QSM MRI ABC/2 intracranial hemorrhage to noncontrast head CT volume measurement equivalence

BACKGROUND/OBJECTIVES

Intracranial hemorrhage (ICH) volume assessment is an important part of patient management and is routinely obtained by non-contrast head CT (NCHCT) using the validated ABC/2 measurement method. Because conventional MRI imaging sequences demonstrate variability in ICH appearance, volumetric analyses for MRI bleed volume in a standardized manner using ABC/2 is not possible. The recently introduced multiecho-complex total field inversion quantitative susceptibility mapping (mcTFI QSM) MRI technique, which maps brain tissue susceptibility to both depict brain tissue structures and quantify tissue susceptibility, may provide a viable alternative. In this study we evaluated mcTFI QSM ABC/2 ICH volume assessment relative to NCHCT.

METHODS

Patients with ICH who had undergone NCHCT and MRI brain scans within 48 h were recruited for this retrospective study. The ABC/2 method was applied to estimate the bleed volume for both NCHCT and MRI by a CAQ-certified neuroradiologist with 10 years of experience and a trained laboratory assistant. Results were analyzed via Bland-Altman (B-A) and linear regression.

RESULTS

54 patients (27 females) who had undergone NCHCT and MRI within 48 h (<24 h., n = 31, 24-48 h, n = 10) were enrolled. mcTFI QSM ICH volume measurement method showed a positive correlation (99.5%) compared to NCHCT. B-A plot comparing ABC/2 ICH volume on NCHCT and mcTFI MRI done for patients within 24 h demonstrates a bias of -0.09%.

CONCLUSIONS

ICH volume calculation using ABC/2 on mcTFI QSM showed a high correlation with NCHCT measurement. These results suggest mcTFI QSM is a promising MRI method for ABC/2 for bleed volume measurement.

Exosomal microRNAs: implications in the pathogenesis and clinical applications of subarachnoid hemorrhage

Subarachnoid hemorrhage (SAH) is a severe acute neurological disorder with a high fatality rate. Early brain injury (EBI) and cerebral vasospasm are two critical complications of SAH that significantly contribute to poor prognosis. Currently, surgical intervention and interventional therapy are the main treatment options for SAH, but their effectiveness is limited. Exosomes, which are a type of extracellular vesicles, play a crucial role in intercellular communication and have been extensively studied in the past decade due to their potential influence on disease progression, diagnosis, and treatment. As one of the most important components of exosomes, miRNA plays both direct and indirect roles in affecting disease progression. Previous research has found that exosomal miRNA is involved in the development of various diseases, such as tumors, chronic hepatitis, atherosclerosis, diabetes, and SAH. This review focuses on exploring the impact of exosomal miRNA on SAH, including its influence on neuronal apoptosis, inflammatory response, and immune activation following SAH. Furthermore, this review highlights the potential clinical applications of exosomal miRNA in the treatment of SAH. Although current research on this topic is limited and the clinical application of exosomal miRNA has inherent limitations, we aim to provide a concise summary of existing research progress and offer new insights for future research directions and trends in this field.

Leveraging the ATP-P2X7 receptor signalling axis to alleviate traumatic CNS damage and related complications

The P2X7 receptor is an exceptional member of the P2X purinergic receptor family, with its activation requiring high concentrations of extracellular adenosine 5'-triphosphate (ATP) that are often associated with tissue damage and inflammation. In the central nervous system (CNS), it is highly expressed in glial cells, particularly in microglia. In this review, we discuss the role and mechanisms of the P2X7 receptor in mediating neuroinflammation and other pathogenic events in a variety of traumatic CNS damage conditions, which lead to loss of neurological and cognitive functions. We raise the perspective on the steady progress in developing CNS-penetrant P2X7 receptor-specific antagonists that leverage the ATP-P2X7 receptor signaling axis as a potential therapeutic strategy to alleviate traumatic CNS damage and related complications.

A Combination of Ex Vivo and In Vivo Strategies for Evaluating How Much New Oral Anticoagulants Exacerbate Experimental Intracerebral Bleeding

Background  Intracerebral hemorrhage is the most serious complication of anticoagulant therapy but the effects of different types of oral anticoagulants on the expansion of these hemorrhages are still unclear. Clinical studies have revealed controversial results; more robust and long-term clinical evaluations are necessary to define their outcomes. An alternative is to test the effect of these drugs in experimental models of intracerebral bleeding induced in animals. Aims  To test new oral anticoagulants (dabigatran etexilate, rivaroxaban, and apixaban) in an experimental model of intracerebral hemorrhage induced by collagenase injection into the brain striatum of rats. Warfarin was used for comparison. Methods  Ex vivo anticoagulant assays and an experimental model of venous thrombosis were employed to determine the doses and periods of time required for the anticoagulants to achieve their maximum effects. Subsequently, volumes of brain hematoma were evaluated after administration of the anticoagulants, using these same parameters. Volumes of brain hematoma were evaluated by magnetic resonance imaging, H&E (hematoxylin and eosin) staining, and Evans blue extravasation. Neuromotor function was assessed by the elevated body swing test. Results and Conclusions  The new oral anticoagulants did not increase intracranial bleeding compared with control animals, while warfarin markedly favored expansion of the hematomas, as revealed by magnetic resonance imaging and H&E staining. Dabigatran etexilate caused a modest but statistically significant increase in Evans blue extravasation. We did not observe significant differences in elevated body swing tests among the experimental groups. The new oral anticoagulants may provide a better control over a brain hemorrhage than warfarin.

Intracranial hemorrhage management in the multi-omics era

Intracranial hemorrhage (ICH) is a devastating disorder. Neuroprotective strategies that prevent tissue injury and improve functional outcomes have been identified in multiple animal models of ICH. However, these potential interventions in clinical trials produced generally disappointing results. With progress in omics, studies of omics data, including genomics, transcriptomics, epigenetics, proteomics, metabolomics, and the gut microbiome, may help promote precision medicine. In this review, we focused on introducing the applications of all omics in ICH and shed light on all of the considerable advantages to systematically analyze the necessity and importance of multiple omics technology in ICH.

Using the ICH score during acute telestroke consults to triage transfer to tertiary centers

OBJECTIVE

Constrained resources at tertiary centers indicate a need for re-exploration of the practice of routinely transferring all community hospital patients with complex conditions such as hemorrhagic stroke (ICH). We addressed the clinical question of whether information available during acute care telestroke consults could identify ICH patients not requiring specialty services or neurosurgical intervention who could safely remain at the local center for care.

DESIGN

Retrospective cohort analysis abstracting clinical factors to identify ICH patients associated with need for tertiary care or neurosurgical intervention.

SETTING

The Duke Telestroke Network (DTN) in Central NC and Southern Virginia.

PATIENTS

All DTN transferred ICH patients January 1, 2017 to December 31, 2018.

INTERVENTIONS

We defined neurosurgical intervention as craniotomy, digital subtraction angiography, or external ventricular drain placement.

MEASUREMENTS AND RESULTS

We identified 116 transferred ICH patients. Sixty-two were female, the median Glasgow coma score (GCS) was 13, and the median ICU and hospital length of stay were 2 and 7 days respectively. Thirty of the patients were offered and 27 ultimately received neurosurgical intervention. Using inclusion/exclusion criteria from two ICH surgical trials would have increased the intervention group to 35 patients (30%). Components of the ICH score differentiated surgical from non-surgical patients; patients with an ICH score of <2 and GCS ≥13 received no interventions. Nearly 50% of patients could receive medical management locally.

CONCLUSIONS

Coupling the ICH score and GCS can provide triage guidance identifying patients for retention at the referring center. This retained population is distinct from patients eligible for current or novel surgical interventions. This approach provides a framework for assessment of transfers across specialty areas and furthers the value of telehealth networks.

Prognostic value of inflammation biomarkers for 30-day mortality in critically ill patients with stroke

Objective

To explore the values of neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), neutrophil to albumin ratio (NAR), prognostic nutritional index (PNI), systemic immune inflammatory index (SII) and red cell distribution width to albumin ratio (RA) for evaluating the risk of 30-day mortality of ischemic stroke or hemorrhagic stroke patients.

Methods

In this cohort study, the data of 1,601 patients diagnosed with stroke were extracted from the Medical Information Mart for Intensive Care III (MIMIC-III) database. Among them, 908 were hemorrhagic stroke patients and 693 were ischemic stroke patients. Demographic and clinical variables of patients were collected. Univariate and multivariable Cox regression were performed to evaluate the predictive values of NLR, PLR, SII, NAR, RA, and PNI for 30-day mortality in hemorrhagic stroke or ischemic stroke patients. The receiver operator characteristic (ROC) curves were plotted to assess the predictive values of NLR, NAR, and RA for 30-day mortality of hemorrhagic stroke patients.

Results

At the end of follow-up, 226 hemorrhagic stroke patients and 216 ischemic stroke patients died. The elevated NLR level was associated with increased risk of 30-day mortality in hemorrhagic stroke [hazard ratio (HR) = 1.17, 95% confidence interval (CI): 1.06-1.29]. The increased NAR level was associated with elevated risk of 30-day mortality in hemorrhagic stroke (HR = 1.16, 95% CI: 1.02-1.30). The high RA level was linked with increased risk of 30-day mortality (HR = 1.44, 95% CI: 1.23-1.69). No significant correlation was observed in these inflammation biomarkers with the risk of 30-day mortality in ischemic stroke patients. The area under the curves (AUCs) of NLR, RA, and NAR for evaluating the risk of 30-day mortality of hemorrhagic stroke patients were 0.552 (95% CI: 0.503-0.601), 0.644 (95% CI: 0.590-0.699) and 0.541 (95% CI: 0.490-0.592).

Conclusion

NLR, NAR, and RA were potential prognostic biomarkers for predicting 30-day mortality of hemorrhagic stroke patients, which might provide clinicians an easy and cheap way to quickly identify patients with high risk of mortality.

Endothelial cell TRPA1 activity exacerbates cerebral hemorrhage during severe hypertension

Introduction: Hypoxia-induced dilation of cerebral arteries orchestrated by Ca2+-permeable transient receptor potential ankyrin 1 (TRPA1) cation channels on endothelial cells is neuroprotective during ischemic stroke, but it is unknown if the channel has a similar impact during hemorrhagic stroke. TRPA1 channels are endogenously activated by lipid peroxide metabolites generated by reactive oxygen species (ROS). Uncontrolled hypertension, a primary risk factor for the development of hemorrhagic stroke, is associated with increased ROS production and oxidative stress. Therefore, we hypothesized that TRPA1 channel activity is increased during hemorrhagic stroke. Methods: Severe, chronic hypertension was induced in control (Trpa1 fl/fl) and endothelial cell-specific TRPA1 knockout (Trpa1-ecKO) mice using a combination of chronic angiotensin II administration, a high-salt diet, and the addition of a nitric oxide synthase inhibitor to drinking water. Blood pressure was measured in awake, freely-moving mice using surgically placed radiotelemetry transmitters. TRPA1-dependent cerebral artery dilation was evaluated with pressure myography, and expression of TRPA1 and NADPH oxidase (NOX) isoforms in arteries from both groups was determined using PCR and Western blotting techniques. In addition, ROS generation capacity was evaluated using a lucigenin assay. Histology was performed to examine intracerebral hemorrhage lesion size and location. Results: All animals became hypertensive, and a majority developed intracerebral hemorrhages or died of unknown causes. Baseline blood pressure and responses to the hypertensive stimulus did not differ between groups. Expression of TRPA1 in cerebral arteries from control mice was not altered after 28 days of treatment, but expression of three NOX isoforms and the capacity for ROS generation was increased in hypertensive animals. NOX-dependent activation of TRPA1 channels dilated cerebral arteries from hypertensive animals to a greater extent compared with controls. The number of intracerebral hemorrhage lesions in hypertensive animals did not differ between control and Trpa1-ecKO animals but were significantly smaller in Trpa1-ecKO mice. Morbidity and mortality did not differ between groups. Discussion: We conclude that endothelial cell TRPA1 channel activity increases cerebral blood flow during hypertension resulting in increased extravasation of blood during intracerebral hemorrhage events; however, this effect does not impact overall survival. Our data suggest that blocking TRPA1 channels may not be helpful for treating hypertension-associated hemorrhagic stroke in a clinical setting.

Fast Iterative Shrinkage-Thresholding Algorithm with Continuation for Brain Injury Monitoring Imaging Based on Electrical Impedance Tomography

Electrical impedance tomography (EIT) is low-cost and noninvasive and has the potential for real-time imaging and bedside monitoring of brain injury. However, brain injury monitoring by EIT imaging suffers from image noise (IN) and resolution problems, causing blurred reconstructions. To address these problems, a least absolute shrinkage and selection operator model is built, and a fast iterative shrinkage-thresholding algorithm with continuation (FISTA-C) is proposed. Results of numerical simulations and head phantom experiments indicate that FISTA-C reduces IN by 63.2%, 47.2%, and 29.9% and 54.4%, 44.7%, and 22.7%, respectively, when compared with the damped least-squares algorithm, the split Bergman, and the FISTA algorithms. When the signal-to-noise ratio of the measurements is 80-50 dB, FISTA-C can reduce IN by 83.3%, 72.3%, and 68.7% on average when compared with the three algorithms, respectively. Both simulation and phantom experiments suggest that FISTA-C produces the best image resolution and can identify the two closest targets. Moreover, FISTA-C is more practical for clinical application because it does not require excessive parameter adjustments. This technology can provide better reconstruction performance and significantly outperforms the traditional algorithms in terms of IN and resolution and is expected to offer a general algorithm for brain injury monitoring imaging via EIT.

Space-constrained optimized Tikhonov regularization method for 3D hemorrhage reconstruction by open magnetic induction tomography

Objective. Open magnetic induction tomography (MIT) is a promising technique for detecting the intracranial hemorrhage due to the non-radioactive, non-invasive and portable features. However, severe inhomogeneity of the sensitivity distribution under the open MIT sensor array and the ill-conditioned nature of MIT inverse problem limit the imaging quality in hemorrhage reconstruction. More accurate and robust imaging algorithms are urgently needed in clinical diagnosis.Approach.In this study, the space-constrained optimized Tikhonov regularization (SOTR) method is proposed for 3D hemorrhage reconstruction by open MIT. The sensitivity matrix is optimized according to the characteristics of sensitivity distribution under the open MIT sensor array. To test the performance of the SOTR method, 3D anatomical head models with hemorrhages in different volumes and locations were established. The images of the hemorrhages were reconstructed by the Tikhonov regularization (TR), total variation (TV) regularization, isotropic SOTR, and anisotropic SOTR method. Correlation coefficientCC,localization errorLE,and volume errorVEwere calculated to evaluate the hemorrhage imaging quality. Mainresults. Compared with the traditional sensitivity matrix, the optimized sensitivity matrix has smaller column number and better uniformity, which alleviates the under-determined and ill-conditioned problem of MIT. The imaging results indicate that both the isotropic and anisotropic SOTR methods can effectively improve the reconstruction accuracy for the location and volume of the hemorrhages. Moreover, compared with the TR and TV methods, the two SOTR methods are more robust against the measurement noise.Significance. The proposed method improves the imaging quality of the intracranial hemorrhage, which promotes the clinical applications of open MIT.

Utility of Exosomes in Ischemic and Hemorrhagic Stroke Diagnosis and Treatment

Stroke is the leading cause of death and neurological disorders worldwide. However, diagnostic techniques and treatments for stroke patients are still limited for certain types of stroke. Intensive research has been conducted so far to find suitable diagnostic techniques and treatments, but so far there has been no success. In recent years, various studies have drawn much attention to the clinical value of utilizing the mechanism of exosomes, low toxicity, biodegradability, and the ability to cross the blood–brain barrier. Recent studies have been reported on the use of biomarkers and protective and recovery effects of exosomes derived from stem cells or various cells in the diagnostic stage after stroke. This review focuses on publications describing changes in diagnostic biomarkers of exosomes following various strokes and processes for various potential applications as therapeutics.

Systolic Blood Pressure Variability When Transitioning From Intravenous to Enteral Antihypertensive Agents in Patients With Hemorrhagic Strokes

Background/Objective

Systolic blood pressure variability (SBPV) in patients with intracranial hemorrhage (ICH) and subarachnoid hemorrhage (SAH) is associated with an increased risk of acute kidney injury (AKI) and mortality. SBPV is a strong predictor of poor functional outcomes in patients with ICH. Intravenous (IV) antihypertensive agents are commonly used to achieve sustained target blood pressure goals; however, this is not a feasible long-term option. The transition from IV to enteral antihypertensives is not yet well established in patients with ICH and SAH. This study aimed to assess the effect of the number of antihypertensive agents and overlap time during the transition period from IV to enteral route on SBPV in patients with ICH and SAH.

Methods

This retrospective single-center study was conducted at a tertiary teaching hospital in Riyadh, Saudi Arabia. Data were extracted from electronic medical records after obtaining Institutional Review Board approval. Patients were included if they were &gt;18 years old, admitted with spontaneous ICH or SAH, and received continuous infusion antihypertensives prior to transitioning to the enteral route. The major outcome was the effect of the number of antihypertensive agents and overlap time on SBPV during the transition process. Minor outcomes included the effect of the number of antihypertensive agents and overlap time on heart rate variability and the incidence of AKI on day 7.

Results

After the screening, we included 102 patients. Based on our regression model, the number of enteral antihypertensive agents upon transitioning from IV to enteral antihypertensive therapy had no effect on SBPV in the intensive care unit (ICU) among our patients (p-value = 0.274). However, the prolonged overlap was associated with reduced SBPV in the ICU (p-value = 0.012). No differences were observed between the groups in heart rate variation or AKI rate.

Conclusions

In patients with ICH and SAH, prolonged overlap of enteral antihypertensive agents to overlap with intravenous antihypertensive therapy may result in lower SBPV. This finding needs to be confirmed on a larger scale with more robust study designs for patients with ICH and SAH.

Microglia Phenotypes in Aging and Neurodegenerative Diseases

Neuroinflammation is a hallmark of many neurodegenerative diseases (NDs) and plays a fundamental role in mediating the onset and progression of disease. Microglia, which function as first-line immune guardians of the central nervous system (CNS), are the central drivers of neuroinflammation. Numerous human postmortem studies and in vivo imaging analyses have shown chronically activated microglia in patients with various acute and chronic neuropathological diseases. While microglial activation is a common feature of many NDs, the exact role of microglia in various pathological states is complex and often contradictory. However, there is a consensus that microglia play a biphasic role in pathological conditions, with detrimental and protective phenotypes, and the overall response of microglia and the activation of different phenotypes depends on the nature and duration of the inflammatory insult, as well as the stage of disease development. This review provides a comprehensive overview of current research on the various microglia phenotypes and inflammatory responses in health, aging, and NDs, with a special emphasis on the heterogeneous phenotypic response of microglia in acute and chronic diseases such as hemorrhagic stroke (HS), Alzheimer’s disease (AD), and Parkinson’s disease (PD). The primary focus is translational research in preclinical animal models and bulk/single-cell transcriptome studies in human postmortem samples. Additionally, this review covers key microglial receptors and signaling pathways that are potential therapeutic targets to regulate microglial inflammatory responses during aging and in NDs. Additionally, age-, sex-, and species-specific microglial differences will be briefly reviewed.

Ludic Table: a comparative study between playful rehabilitation and kinesiotherapy in restricting upper limb movements in individuals with stroke

Stroke is a neurological syndrome resulting from the sudden interruption of blood flow. Among the symptoms/consequences of the stroke are muscle weakness in the lower and/or upper limbs, decreased sensitivity, altered fine motor skills, proprioception, and reflections. The treatment for the motor consequences is orthopedic management, in which the physiotherapist assists the individual in repetitive range of motion exercises, which can be demotivating during the treatment. The Ludic Table (LT), on the other hand, incorporates playfulness into therapy, making it a motivating tool. This research describes the comparative study between kinesiotherapy techniques and exercises using the LT, applied to the development of upper limb movements. For this, fourteen volunteers were divided into groups, submitted to interventions according to the techniques, and evaluated using systems such as goniometry, HAQ-DI, GMFM-88, and neurofunctional assessment. In general, it can be stated that regardless of the intervention, the individuals obtained gain in movements (minimum average of 7 degrees) and that the use of the LT allows the development of the angular amplitude and the reduction of the effects of spasticity. The individuals submitted to the intervention through the LT obtained the development of a greater number of articular movements of the shoulder and elbow.

Evaluation of Intracranial Hypertension in Patients With Hypertensive Intracerebral Hemorrhage Using Texture Analysis

Purpose

Texture analysis based on clinical images had been widely used in neurological diseases. This study aimed to achieve depth information of computed tomography (CT) images by texture analysis and to establish a model for noninvasive evaluation of intracranial pressure (ICP) in patients with hypertensive intracerebral hemorrhage (HICH).

Methods

Forty-seven patients with HICH were selected. Related CT images and ICP value were collected. The morphological features of hematoma volume, midline shift, and ventriculocranial ratio were measured. Forty textural features were extracted from regions of interest. Four models were established to predict intracranial hypertension with morphological features, textural features of anterior horn, textural features of temporal lobe, and textural features of posterior horn.

Results

Model of posterior horn had the highest ability to predict intracranial hypertension (AUC = 0.90, F1 score = 0.72), followed by model of anterior horn (AUC = 0.70, F1 score = 0.53) and model of temporal lobe (AUC = 0.70, F1 score = 0.58), and model of morphological features displayed the worst performance (AUC = 0.42, F1 score = 0.38).

Conclusion

Texture analysis can realize interpretation of CT images in depth, which has great potential in noninvasive evaluation of intracranial hypertension.

Differential associations of particle size ranges and constituents with stroke emergency-room visits in Shanghai, China

BACKGROUND AND PURPOSE

Fine particulate matter (PM_2.5) has been associated with increased risks of stroke, but it remains unclear which specific size ranges and chemical constituents dominate the effects of PM_2.5 on stroke. We aimed to evaluate the associations of size-segregated particles and various constituents of PM_2.5 with daily emergency-room visits for stroke.

METHODS

We conducted a time-series study to investigate the associations of 5 particle size ranges from 0.01 to 2.5 µm and 35 constituents of PM_2.5 with the daily emergency-room visits for stroke in Shanghai, from 2014 to 2019. Over-dispersed generalized additive models were used to estimate the associations. The robustness of these associations was evaluated by additionally controlling for PM_2.5 mass.

RESULTS

For size ranges from 0.01 to 0.3 µm, there were significant positive associations between particle number concentrations and daily emergency-room visits for stroke with the strongest associations occurring for the size range 0.05-0.1 µm. The size-dependent pattern was not changed by adjusting for PM_2.5 and gaseous pollutants. The associations of daily emergency-room visits for stroke also varied considerably by various PM_2.5 constituents. After controlling for the simultaneous exposure to PM_2.5 and gaseous pollutants in two-pollutant models, we identified 11 out of 35 constituents that had robust associations, these being organic carbon, elemental carbon, chlorine, magnesium, ammonium, nitrate, sulfate, copper, manganese, lead and zinc.

CONCLUSION

Ultra-fine particles and some PM_2.5 constituents (i.e., carbonaceous fractions, inorganic ions and some elements) may be mainly responsible for the excess risk of stroke induced by PM_2.5.

Hemorrhagic Stroke: Endoscopic Aspiration

Intracerebral hemorrhage (ICH) and intraventricular hemorrhage (IVH) carry a very dismal prognosis. Several medical and surgical attempts have been made to reduce mortality and to improve neurological outcomes in survivors. Aggressive surgical treatment of ICH through craniotomy and microsurgical evacuation did not prove to be beneficial to these patients, compared to the best medical treatment. Similarly, the conventional treatment of IVH using an EVD is often effective in controlling ICP only initially, as it is very likely for the EVD to become obstructed by blood clots, requiring frequent replacements with a consequent increase of infection rates.Minimally invasive techniques have been proposed to manage these cases. Some are based on fibrinolytic agents that are infused in the hemorrhagic site through catheters with a single burr hole. Others are possible thanks to the development of neuroendoscopy. Endoscopic removal of ICH through a mini-craniotomy or a single burr hole, and via a parafascicular white matter trajectory, proved to reduce mortality in this population, and further randomized trials are expected to show whether also a better neurological outcome can be obtained in survivors. Moreover, endoscopy offers the opportunity to access the ventricular system to aspirate blood clots in patients with IVH. In such cases, the restoration of patency of the entire CSF pathway has the potential to improve outcome and reduce complications and now it is believed to decrease shunt-dependency.

Recent advances and perspectives of postoperative neurological disorders in the elderly surgical patients

Postoperative neurological disorders, including postoperative delirium (POD), postoperative cognitive dysfunction (POCD), postoperative covert ischemic stroke, and hemorrhagic stroke, are challenging clinical problems in the emerging aged surgical population. These disorders can deteriorate functional outcomes and long‐term quality of life after surgery, resulting in a substantial social and financial burden to the family and society. Understanding predisposing and precipitating factors may promote individualized preventive treatment for each disorder, as several risk factors are modifiable. Besides prevention, timely identification and treatment of etiologies and symptoms can contribute to better recovery from postoperative neurological disorders and lower risk of long‐term cognitive impairment, disability, and even death. Herein, we summarize the diagnosis, risk factors, prevention, and treatment of these postoperative complications, with emphasis on recent advances and perspectives.

Stroke and Pneumonia: Mechanisms, Risk Factors, Management, and Prevention

A stroke is a cerebrovascular medical emergency characterized by the sudden loss of neurological function due to interruption to the blood supply. A serious and common complication of stroke is pneumonia. This review article outlined various studies in order to understand the pathogenesis pathways that lead to the development of stroke-associated pneumonia, as well as therapeutic and preventive options to reduce pneumonia. The article looked for risk factors that increase the risk of developing pneumonia among stroke patients. In addition, it has reviewed various therapeutic modalities, such as postural modifications, pharmacological treatment, and other unique treatments, in an attempt to find which of them are efficient to decrease the occurrence of pneumonia and which of them are not. The article also attempts to emphasize the importance of early screening for dysphagia among stroke patients and demonstrates the importance of preventive strategies that can be easily implemented, such as routine oral care and behavioral modifications.

Sensitivity Analysis Highlights the Importance of Accurate Head Models for Electrical Impedance Tomography Monitoring of Intracerebral Hemorrhagic Stroke

OBJECTIVE

Electrical impedance tomography (EIT) has been proposed as a novel tool for diagnosing stroke. However, so far, the clinical feasibility is unresolved. In this study, we aim to investigate the need for accurate head modeling in EIT and how the inhomogeneities of the head contribute to the EIT measurement and affect its feasibility in monitoring the progression of a hemorrhagic stroke.

METHODS

We compared anatomically detailed six- and three-layer finite element models of a human head and computed the resulting scalp electrode potentials and the lead fields of selected electrode configurations. We visualized the resulting EIT measurement sensitivity distributions, computed the scalp electrode potentials, and examined the inverse imaging with selected cases. The effect of accurate tissue geometry and conductivity values on the EIT measurement is assessed with multiple different hemorrhagic perturbation locations and sizes.

RESULTS

Our results show that accurate tissue geometries and conductivity values inside the cranial cavity, especially the highly conductive cerebral spinal fluid, significantly affect EIT measurement sensitivity distribution and measured potentials.

CONCLUSIONS

We can conclude that the three-layer head models commonly used in EIT literature cannot depict the current paths correctly in the head. Thus, our study highlights the need to consider the detailed geometry of the cerebrospinal fluid (CSF) in EIT.

SIGNIFICANCE

The results clearly show that the CSF should be considered in the head EIT calculations.

Investigation of Taurine Derivative Magnesium-Bis-(2-Aminoethanesulfonic)-Butadioateon Alleviation of Neurological Defects in Simulated Hemorrhagic Stroke in Rats

Stroke or ischemia is caused by a blockage in a specific blood vessel that partially or completely reduces the blood flow to the brain. Nutritional factors such as antioxidants and healthy eating patterns are important variables in preventing stroke. Molecular composition properties such as molecular binding and screening can be used to evaluate the specific activity and morphological changes. The present study aimed to evaluate the effectiveness of pharmacological correction of the consequences of a hemorrhagic stroke in rats with a new derivative of taurine magnesium-bis-(2-aminoethanesulfonic)-butadioate. The animals (n=170) were divided into four groups as follows: 1) control group (n=20), 2) group 2 suffered a hemorrhagic stroke without pharmacological correction (n=50), 3) group 3 (n=50) underwent simulation of hemorrhagic stroke received Taurine at the dose of 50 mg/kg, 4) Group 4 underwent simulation of hemorrhagic stroke with correction of hemorrhagic stroke with magnesium-bis-(2-aminoethanesulfonic)-butadioate at the dose of 150 mg/kg (LKHT 3-17) (n=50). Hemorrhagic stroke was induced by transfusing autologous blood into the parietal lobe of the right hemisphere of the brain. Lethality, neurological status, locomotor, and exploratory behavior, as well as the morphological pattern of the brain damage, were assessed on the 1st, 3rd, and 7th days after the pathology simulation. Neurological deficit was determined in animals by the McGrow stroke index scale. The locomotor and exploratory behavior was evaluated using the Acti-track software and hardware complex. Two criteria were considered when assessing morphological changes in the brain: the average thickness of the cerebral cortex (in micrometers) and the number of neurons without degenerative changes. LKHT 3-17 (150 mg/kg) and taurine (50 mg/kg) reduced lethality by 1.7 and 1.36 times, respectively, on the 3rd day after stroke compared to that of the control (p<0.05). In parallel, a neurological deficit was effectively corrected LKHT 3-17 and taurine to 5.3±0.8 and 6.5±0.9, respectively, on the 1st day in contrast to the control of 8.1±0.7 points. The locomotor and exploratory behavior was significantly different on the 7th day and was accompanied by a significant increase in total activity under the influence of LKHT 3-17 to 491 conventional units (CU) compared to the control of 110 conventional units. On the 1st day, the thickness of the cortex was 1943.7±44.08 µm, and 1491.0±38.61 µm in the control and LKHT 3-17 groups, respectively. The number of neurons without neurodegenerative changes prevailed in LKHT 3-17 group (18.7±4.32), and the lowest number was observed in the group without pharmacological correction of the pathology (14.3±3.78). The taurine derivative magnesium-bis-(2-aminoethanesulfonic)-butadioate, which is a combination of the amino acid, magnesium ion, and succinic acid, decreases the neurological deficits, lethality, and enhances the locomotor and exploratory behavior in experimental hemorrhagic stroke in rats. The effect of the studied medication on the dynamics of molecular pathophysiological mechanisms occurring in the cell requires additional research.

Molecular Mechanisms of Neuroimmune Crosstalk in the Pathogenesis of Stroke

Stroke disrupts the homeostatic balance within the brain and is associated with a significant accumulation of necrotic cellular debris, fluid, and peripheral immune cells in the central nervous system (CNS). Additionally, cells, antigens, and other factors exit the brain into the periphery via damaged blood–brain barrier cells, glymphatic transport mechanisms, and lymphatic vessels, which dramatically influence the systemic immune response and lead to complex neuroimmune communication. As a result, the immunological response after stroke is a highly dynamic event that involves communication between multiple organ systems and cell types, with significant consequences on not only the initial stroke tissue injury but long-term recovery in the CNS. In this review, we discuss the complex immunological and physiological interactions that occur after stroke with a focus on how the peripheral immune system and CNS communicate to regulate post-stroke brain homeostasis. First, we discuss the post-stroke immune cascade across different contexts as well as homeostatic regulation within the brain. Then, we focus on the lymphatic vessels surrounding the brain and their ability to coordinate both immune response and fluid homeostasis within the brain after stroke. Finally, we discuss how therapeutic manipulation of peripheral systems may provide new mechanisms to treat stroke injury.

Neuritin improves the neurological functional recovery after experimental intracerebral hemorrhage in mice

Stroke is one of the leading causes of death worldwide, with intracerebral hemorrhage (ICH) being the most lethal subtype. Neuritin (Nrn) is a neurotropic factor that has been reported to have neuroprotective effects in acute brain and spinal cord injury. However, whether Nrn has a protective role in ICH has not been investigated. In this study, ICH was induced in C57BL/6 J mice by injection of collagenase VII, while the overexpression of Nrn in the striatum was induced by an adeno-associated virus serotype 9 (AAV9) vector. We found that compared with GFP-ICH mice, Nrn-ICH mice showed improved performance in the corner, cylinder and forelimb tests after ICH, and showed less weight loss and more rapid weight recovery. Overexpression of Nrn reduced brain lesions, edema, neuronal death and white matter and synaptic integrity dysfunction caused by ICH. Western blot results showed that phosphorylated PERK and ATF4 were significantly inhibited, while phosphorylation of Akt/mammalian target of rapamycin was increased in the Nrn-ICH group, compared with the GFP-ICH group. Whole cell recording from motor neurons indicated that overexpression of Nrn reversed the decrease of spontaneous excitatory postsynaptic currents (sEPSCs) and action potential frequencies induced by ICH. These data show that Nrn improves neurological deficits in mice with ICH by reducing brain lesions and edema, inhibiting neuronal death, and possibly by increasing neuronal connections.

Risk Factors for Postoperative Rebleeding and Short-Term Prognosis of Spontaneous Cerebellar Hemorrhage

Purpose

Postoperative rebleeding (PRB) is one of the most severe complications after hematoma evacuation of spontaneous intracerebral hemorrhage (ICH). PRB has been proven to be an independent risk factor for poor prognosis. Previous studies have shown that spot sign and blend sign are independent risk factors for PRB of spontaneous ICH. However, the risk factors for PRB of spontaneous cerebellar hemorrhage (SCH) have not been elucidated. The aim of the present study was to investigate the possible risk factors for PRB and short-term prognosis of patients with SCH.

Patients and Methods

This study identified 62 patients with SCH who underwent hematoma evacuation in our department. Risk factors for PRB and short-term prognosis were identified by a univariable logistic regression model, and predictors with a P value of less than 0.05 were included in the multivariable logistic regression model to identify independent predictors. A receiver operating characteristic (ROC) curve was created to test the sensitivity and specificity of independent risk factors.

Results

Hematoma volume was the only independent predictor of PRB (OR=15.14, 95% CI=1.08–213.1, P=0.044). The sensitivity and specificity of hematoma volume to PRB were 63.6% and 89.7%, respectively, and the cutoff value of hematoma volume was >29.3 mL. GCS score ≤8 (OR=5.131, 95% CI=1.030–25.554, P=0.046) and PRB (OR=13.17, 95% CI=1.316–131.798, P=0.028) were independent risk factors for poor prognosis of patients with SCH. The sensitivity and specificity of the GCS score to poor prognosis were 66.7% and 86.2%, respectively. The sensitivity and specificity of the PRB to poor prognosis were 36.4% and 96.6%, respectively.

Conclusion

Hematoma volume is likely to be a strong predictor of PRB among patients with SCH. GCS scores ≤8 on arrival and PRB were significant predictors of short-term poor outcome.

L-3-n-butylphthalide attenuates inflammation response and brain edema in rat intracerebral hemorrhage model

L-3-n-butylphthalide(NBP), a compound found in Apium graveolens Linn seed extracts, has a therapeutic effect on acute ischemic stroke. The pathological inflammatory pathways and consequent brain edema in intracerebral hemorrhage (ICH) share some similar characteristics with ischemic stroke. We hypothesized that NBP has anti-inflammatory and therapeutic effects on rats with ICH. ICH was induced by an infusion of bacterial collagenase type IV into the unilateral striatum of anesthetized rats. The therapeutic effect of NBP was measured by assessing neurological function, brain water content, blood-brain barrier permeability, and expression of tumor necrosis factor-alpha (TNF-α) and matrix metalloproteinase-9 (MMP-9) around the hematoma 48 hours after surgery. Magnetic resonance imaging was performed 4 and 48 hours after ICH induction, and ICH-induced injured area volumes were measured using T2-weighted images. The NBP treatment group performed better in the neurological function test than the vehicle group. Moreover, in comparison with the vehicle group, NBP group showed a lower expanded hematoma volume, brain water content, blood-brain barrier permeability, and TNF-α/ MMP-9 expression level. Our results indicate that NBP attenuates inflammation and brain edema in rat ICH model. Therefore, our findings also provide a potential therapeutic strategy for the treatment of ICH with NBP.

Caveolin-1 in Stroke Neuropathology and Neuroprotection: A Novel Molecular Therapeutic Target for Ischemic-Related Injury

Cardiovascular disease and associated cerebral stroke are a global epidemic attributed to genetic and epigenetic factors, such as diet, life style and an increasingly sedentary existence due to technological advances in both the developing and developed world. There are approximately 5.9 million stroke-related deaths worldwide annually. Current epidemiological data indicate that nearly 16.9 million people worldwide suffer a new or recurrent stroke yearly. In 2014 alone, 2.4% of adults in the United States (US) were estimated to experience stroke, which is the leading cause of adult disability and the fifth leading cause of death in the US There are 2 main types of stroke: Hemorrhagic (HS) and ischemic stroke (IS), with IS occurring more frequently. HS is caused by intra-cerebral hemorrhage mainly due to high blood pressure, while IS is caused by either embolic or thrombotic stroke. Both result in motor impairments, numbness or abnormal sensations, cognitive deficits, and mood disorders (e.g. depression). This review focuses on the 1) pathophysiology of stroke (neuronal cell loss, defective blood brain barrier, microglia activation, and inflammation), 2) the role of the membrane protein caveolin- 1 (Cav-1) in normal brain physiology and stroke-induced changes, and, 3) we briefly discussed the potential therapeutic role of Cav-1 in recovery following stroke.

Efficacy and safety of four interventions for spontaneous supratentorial intracerebral hemorrhage: a network meta-analysis

OBJECT

To investigate the efficacy and safety of four interventions of spontaneous intracerebral hemorrhage simultaneously.

METHODS

PubMed, EmBase, Web of Science, and the Cochrane Central Register of Controlled Trials were searched for randomized controlled trials (RCTs) investigating endoscopic surgery (ES), minimally invasive puncture surgery (MIPS), conventional craniotomy (CC), and/or conservative medical treatment (CMT). Good functional outcome, death, and hemorrhage recurrence rates were evaluated by a network meta-analysis.

RESULTS

20 RCTs with 3603 patients were included. Compared with CMT, a higher rate of good functional outcome was found after ES (RR=2.21, 95% CI 1.37 to 3.55) and MIPS (RR=1.47, 95% CI 1.24 to 1.73). Both ES (RR=0.62, 95% CI 0.44 to 0.86) and MIPS (RR=0.72, 95% CI 0.58 to 0.90) markedly reduced the rate of death. However, there was no significant difference in efficacy and safety between ES and MIPS. The top ranked P score for the efficacy outcome was for ES (P score=0.9810). ES (P-score=0.0709) ranked lowest for the primary safety outcome. There was a higher risk of hemorrhage recurrence after CC (RR=3.80, 95% CI 1.90 to 7.63) and MIPS (RR=2.86, 95% CI 1.70 to 4.82) compared with CMT whereas no significant difference was found for ES (RR=1.46, 95% CI 0.53 to 4.02).

CONCLUSIONS

The results suggest that both ES and MIPS significantly improve neurological function and reduce the risk of death compared with CMT, and there is no significant difference between ES and MIPS. Ranking of P scores revealed that ES may be the most optimal intervention to improve functional outcome and prevent death. This needs to be evaluated further.

Acute parenchymal hemorrhage of three cases report after burr hole drainage of chronic subdural hematoma

Chronic subdural hematoma (CSDH) is one of the most common neurological diseases, which mainly occurs among elderly people and usually develop after minor head injuries. Over the years, a simple burr hole evacuation of the hematoma has been accepted as the widespread method for most cases of CSDH, but acute parenchymal hemorrhage is a rare and deadly complication after surgery. We report three elderly cases of post-operative parenchymal hemorrhage and analyse the underlying factors and formulate relevant strategies in this article. Three advanced age patients had been admitted to our department with gradually increasing headache and limb activity disorder urgently and underwent an emergency operation of burr hole drainage of CSDH in frontal-temporal region after preoperative evaluations and examinations. Unfortunately, acute post-operative parenchymal hemorrhage occurred in three advanced age patients. Ultimately, the patients achieved satisfying outcome with no significant neurological deficit through conservative treatment. The exact mechanism of such uncommon complications are difficult to explain and remain poorly understood. Advanced age, hypertension, amyloidosis, high perfusion triggered by rapid hematoma release, cerebrospinal fluid (CSF) loss, oral anticoagulant, primary disease aggravation were the main mechanisms which were speculated in our report. Simultaneously, positive measures could be adopt to prevent this rare complication.

TRPV4 channels stimulate Ca2+-induced Ca2+ release in mouse neurons and trigger endoplasmic reticulum stress after intracerebral hemorrhage

Individuals with intracerebral hemorrhage (ICH) suffer varying degrees of neurological dysfunction as a result of neuronal apoptosis, and thus, maintenance of neuronal survival may be crucial to prevent ICH brain injury. Here, we report that the expression of transient receptor potential vanilloid 4 (TRPV4) was upregulated in mouse neurons after ICH. The selective TRPV4 agonist GSK1016790 A aggravated neuronal death whereas the TRPV4 antagonist HC-067047 promoted neuronal survival after ICH. We found that GSK1016790 A triggered Ca²⁺ signals that were amplified and propagated by Ca²⁺-induced Ca²⁺ release (CICR) from the endoplasmic reticulum (ER) in the neurons. ICH recruited inositol triphosphate receptors (IP3Rs) into the TRPV4 protein complex, which positively regulated the activity of TRPV4 channels. Excessive activation of TRPV4 channels destroyed Ca²⁺ homeostasis and induced ER unfolded protein response (UPR). Blocking TRPV4 receptors decreased UPR, inhibited the PERK-CHOP-Bcl-2 signaling pathway and increased neuron survival. Overall, these results suggested that overactivation of TRPV4 channels after ICH ledto the destruction of Ca²⁺ homeostasis, which in turn caused UPR and neural apoptosis. Inhibition of TRPV4 channels is a promising therapy to promote neurons recover, and to ameliorate disability after ICH.

Elevated ESRS, serum FIB, Hcy and stroke history were independent risk factors to PAIS

Background: The aim of this study was to investigate the diagnostic performance of serum homocysteine (Hcy) and Essen stroke risk score (ESRS) in prediction of progressing acute ischemic stroke (PAIS).

Methods One hundred and thirty two acute ischemic stroke (AIS) patients were retrospectively recruited from Daping Hospital, Third Military Medical University from February 2016 to January 2018. The 132 AIS patients were divided into PAIS and non-progressing AIS (NPAIS) groups according to the definition of PAIS. The clinical characteristics, serum Hcy concentration, and ESRS were compared between the PAIS and NPAIS groups. The independent risk factors for PAIS were evaluated by logistic regression analysis. The prediction sensitivity, specificity and area under the ROC curve (AUC) of serum Hcy and ESRS for PAIS were calculated using STATA11.0 software.

Results: The elevated ESRS (OR=1.82, p<0.05), serum fibrinogen (FIB) (OR=1.18, p<0.05), Hcy (OR=1.21, p<0.05) and personal stroke history (OR=1.74, p<0.05) were independent risk factors for PAIS. The serum Hcy of the PAIS and NPAIS groups were 24.59±9.24 (μmol/L) and 18.20±8.29 (μmol/L) respectively with a statistical significance of p<0.05. The ESRS were 3.43±1.09 and 2.60±0.92 for the PAIS and NPAIS groups respectively, with a significance of p<0.05. The prediction sensitivity, specificity and AUC were 76.24%, 67.74% and 0.73 (95%CI:0.63-0.83), respectively, for serum Hcy. For ESRS, the prediction sensitivity, specificity and AUC were 69.99%, 64.52% and 0.74 (95%CI:0.63-0.84) respectively. Correlation between serum Hcy and ESRS was evaluated by a Pearson correlation test. Significant positive correlation between serum Hcy and ESRS was found in PAIS (r=0.54, p<0.05), and NPAIS patients (r=0.78, p<0.01).

Conclusion: Patients with elevated ESRS, serum FIB, Hcy and stroke history had an elevated risk of developing PAIS.

Chronic encapsulated intraventricular hematoma in a pediatric patient: case report

Chronic encapsulated intraventricular hematoma (CEIVH) is a rare, intraventricular, nonneoplastic mass lesion that can become symptomatic from mass effect or obstructive hydrocephalus. Only 5 cases have been reported in the literature, and only one of these occurred in a pediatric patient and dates back to the pre-modern neuroimaging and pre-microsurgical era of neurosurgery. Imaging features can mimic those of many more common intraventricular lesions, such as choroid plexus tumors or cavernous malformations. In all reported symptomatic cases, resection was safely performed and led to a cure and symptom resolution. Here, the authors present a case of CEIVH in a pediatric patient, describe the operative techniques of resection, review the available literature, and discuss current understanding of the pathophysiology, making this the most comprehensive report on this disease entity to date. The case is a 14-year-old boy who presented with headaches and emesis. Computed tomography showed a hyperdense mass in the trigone of the right lateral ventricle. Magnetic resonance imaging showed a contrast-enhancing well-circumscribed mass. Right temporal craniotomy utilizing a posterior middle temporal gyrus transcortical approach was performed, and gross-total resection was achieved. Pathology revealed a CEIVH. The boy's postoperative course was uncomplicated, and he was discharged 2 days after surgery.

Understanding Spreading Depression from Headache to Sudden Unexpected Death

Spreading depression (SD) is a neurophysiological phenomenon characterized by abrupt changes in intracellular ion gradients and sustained depolarization of neurons. It leads to loss of electrical activity, changes in the synaptic architecture, and an altered vascular response. Although SD is often described as a unique phenomenon with homogeneous characteristics, it may be strongly affected by the particular triggering event and by genetic background. Furthermore, SD may contribute differently to the pathogenesis of widely heterogeneous clinical conditions. Indeed, clinical disorders related to SD vary in their presentation and severity, ranging from benign headache conditions (migraine syndromes) to severely disabling events, such as cerebral ischemia, or even death in people with epilepsy. Although the characteristics and mechanisms of SD have been dissected using a variety of approaches, ranging from cells to human models, this phenomenon remains only partially understood because of its complexity and the difficulty of obtaining direct experimental data. Currently, clinical monitoring of SD is limited to patients who require neurosurgical interventions and the placement of subdural electrode strips. Significantly, SD events recorded in humans display electrophysiological features that are essentially the same as those observed in animal models. Further research using existing and new experimental models of SD may allow a better understanding of its core mechanisms, and of their differences in different clinical conditions, fostering opportunities to identify and develop targeted therapies for SD-related disorders and their worst consequences.

Biomaterials Developments for Brain Tissue Engineering

The Central Nervous System (CNS) is a highly complex organ that works as the control centre of the body, managing vital and non-vital functions. Neuro-diseases can lead to the degeneration of neural tissue, breakage of the neuronal networks which can affect vital functions and originate cognitive deficits. The complexity of the neural networks, their components and the low regenerative capacity of the CNS are on the basis for the lack of recovery, having the need for therapies that can promote tissue repair and recovery. Most brain processes are mediated through molecules (e.g. cytokines, neurotransmitters) and cells response accordingly and to surrounding cues, either biological or physical, which offers molecule administration and/or cell transplantation a great potential for use in brain recovery. Biomaterials and in particular, of natural-origin are attractive candidates owed to their intrinsic biological cues and biocompatibility and degradability. Through the use of biomaterials, it is possible to protect the cells/molecules from body clearance, enzymatic degradation while maintaining the components in a place of interest. Moreover, by means of combining several components, it is possible to obtain a more targeted and controlled delivery, to image the biomaterial implantation and its degradation over time and tackling simultaneously occurring events (cell death and inflammation) in brain diseases. In this chapter, it is reviewed some brain-affecting diseases and the current developments on tissue engineering approaches for a functional recovery of the brain from those diseases.

Imaging Diagnosis of Chronic Encapsulated Intracerebral Hematoma, a Comparison of Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) characteristics

Background

Chronic encapsulated intracerebral hematoma (CEICH) is a rare type of intracerebral hematoma that is often misdiagnosed.To explore the characteristics of CEICH on computerized tomography (CT) and magnetic resonance imaging (MRI).

Material/Methods

Clinical, CT, MRI, and susceptibility weighted imaging (SWI) data of 5 patients who were diagnosed with CEICH on surgery and pathology were retrospectively analyzed.

Results

CT showed quasi-circular or elliptical lesions with clear borders in all 5 cases and iso-density or low-density in the center of lesions that were surrounded by peripheral edema in 2 cases. CT showed mass effect in 5 patients. On contrast-enhanced CT, 2 cases exhibited mild ring enhancement, and 3 cases exhibited moderate ring enhancement. MRI showed cystic lesions with high uniform signal on T1-weighted images (T1WI) and T2-weighted images (T2WI), a lowsignal ring sign on the coated cystic lesions on T2WI, a lower signal ring sign on SWI, and ring enhancement after administration of contrast.

Conclusions

CT imaging of CEICH did not reveal any typical characteristics in the studied patients. MRI showed an envelope with a "ring" and intra-capsular bleeding features. MRI is an effective imaging modality for the diagnosis of CEICH.

Intracerebral Hemorrhagic Expansion Occurs in Patients Using Non-Vitamin K Antagonist Oral Anticoagulants Comparable with Patients Using Warfarin

BACKGROUND

Non-vitamin K antagonist oral anticoagulant (NOAC) use has significantly reduced intracerebral hemorrhagic (ICH) risk compared with standard anticoagulant treatment. Hematoma expansion (HE) is a known predictor of mortality in warfarin-associated ICH. Little is known about HE in patients using NOACs.

METHODS

We conducted a retrospective chart review of patients with ICH admitted to Cedars-Sinai Medical Center from October 2010 to June 2016. We identified patients with concomitant administration of an oral anticoagulant and collected data including evidence of HE on imaging and modified Rankin Scale (mRS) at discharge. We defined HE as relative (≥33% increase) or absolute expansion (≥12 mL). We compared outcomes of patients with and without HE.

RESULTS

Out of 814 patients with ICH who were admitted, we identified 9 patients with recent NOAC use and 18 intentionally matched controls on warfarin. We found no significant differences in National Institutes of Health Stroke Scale or ICH score on presentation (median [interquartile range] 15 [5,21] versus 7 [1.25,19.5] [P = .41] and 2 [1,4] versus 1 [1,3] [P = .33]) between patients on NOACs and those on warfarin. Four out of the 9 patients on NOAC and 5 of the 18 patients on warfarin demonstrated HE, with no significant difference (P = .42). There were no significant differences in mRS on discharge between groups (P = .52).

CONCLUSIONS

In our coagulopathic NOAC patient population, HE occurs within 6 hours in 44% of patients. This case series did not have sufficient statistical power to detect significant differences between the groups. To our knowledge, this is one of the largest case series reporting on HE with concomitant NOAC use.

Frequency and Predicting Factors on Chronic Expanding Intracerebral Hematoma in Spontaneous Intracerebral Hemorrhage

BACKGROUND

Chronic expanding intracerebral hematoma is a well-known complication of spontaneous intracerebral hemorrhage. However, because chronic expanding intracerebral hematoma is relatively rare, it has not been studied systemically. The purpose of this study was to characterize a patient population with chronic expanding intracerebral hematoma, and to identify the predictive factors for it.

METHODS

We retrospectively evaluated 112 patients with spontaneous putaminal hemorrhage who were treated at our institution between January 1, 2010 and December 31, 2015. Data on age, sex, Glasgow Coma Scale score, presence of intraventricular hemorrhage, and intracerebral hemorrhage volume were collected, and their predictive values for chronic expanding intracerebral hematoma were investigated. We also evaluated the predictive value of a characteristic radiological finding at onset called the "layer sign," which was represented as a fluid level adjacent to the clot.

RESULTS

Chronic expanding intracerebral hematoma was observed in 4 patients (4.9%) with spontaneous intracerebral hemorrhage. Only the layer sign was significantly related to chronic expanding intracerebral hematoma (P = .003), and was found to be independently associated with chronic expanding intracerebral hematoma in a multivariate analysis (odds ratio, 18.6; 95% confidence interval, 1.19-291.0; P = .037).

CONCLUSIONS

The frequency of chronic expanding intracerebral hematoma in those with spontaneous intracerebral hemorrhage was estimated at 4.9%. The layer sign was a useful factor for predicting chronic expanding intracerebral hematoma.

Local mild hypothermia therapy as an augmentation strategy for minimally invasive surgery of hypertensive intracerebral hemorrhage: a meta-analysis of randomized clinical trials

BACKGROUND

Previous studies reported that the mild hypothermia therapy (MHT) could significantly improve the clinical outcomes for patients with hypertensive intracerebral hemorrhage (HICH). Therefore, this meta-analysis was conducted to systematically assess whether the addition of local MHT (LMHT) could significantly improve the efficacy of minimally invasive surgery (MIS) in treating HICH.

METHODS

Randomized clinical trials on the combined application of MIS and LMHT (MIS+LMHT) vs MIS alone for treating HICH were searched up to September 2016 in databases. Response rate and mortality rate were the primary outcomes, and the neurologic function and Barthel index were the secondary outcomes. Side effects were also analyzed.

RESULTS

Totally, 28 studies composed of 2,325 patients were included to compare the efficacy of MIS+LMHT to MIS alone. The therapeutic effects of MIS+LMHT were significantly better than MIS alone. The pooled odds ratio of response rate and mortality rate was 2.68 (95% confidence interval [CI]=2.22-3.24) and 0.43 (95% CI=0.32-0.57), respectively. In addition, the MIS+LMHT led to a significantly better improvement in the neurologic function and activities of daily living. The incidence of pneumonia was similar between the two treatment methods.

CONCLUSION

These results indicated that compared to MIS alone, the MIS+LMHT could be more effective for the acute treatment of patients with HICH. This treatment modality should be further explored and optimized.