Location Of Brain Lesions Research Articles

Endocan: A Novel Predictor of Endothelial Dysfunction in Silent Brain Infarction.

Silent brain infarction (SBI) has been considered as a subclinical risk factor for symptomatic possible future stroke. We investigated the association between serum inflammatory markers and SBI. Patients (n = 54) diagnosed with SBI as the study group and 52 individuals as the control group were included in this study. Silent brain infarction is defined as a hyperintense lesion that was ≥3 mm in 1 dimension on fluid-attenuated inversion recovery T2-weighted magnetic resonance image, if the patient had normal neurological examination or had an abnormality that was not consistent with the brain lesion locations, after being evaluated by a neurologist. Serum endocan levels (P = .036) and high-sensitivity C-reactive protein (hsCRP; P = .022) were significantly higher in patients with SBI than the controls. Pentraxin 3, erythrocyte sedimentation rate, white blood count, lymphocyte, monocyte, neutrophil, low-density lipoprotein, and triglyceride levels were not significantly different when comparing the groups with and without SBI. There was a significant correlation (r = -0.196; P = .16) between hsCRP and endocan levels in the SBI group. Endocan, a novel biomarker of endothelial pathology, was significantly increased in patients with SBI and may be useful to predict the future risk of stroke.

The effect of low-dose radiation spillage during stereotactic radiosurgery for brain metastases on the development of de novo metastases

Purpose/Objective(s)Stereotactic radiosurgery (SRS) for metastatic disease to the brain is associated with higher in-brain failures compared to whole brain radiation therapy (WBRT). Here we investigated the relationship between low-dose fall off during SRS and location of new brain lesions. Materials and MethodsOne hundred sixty-seven patients treated with single fraction or fractionated SRS for intact or resected brain metastases at our institution from January 2016 to June 2018 were reviewed. Patients with imaging findings of new brain metastases after the initial SRS were included. Patients with WBRT before SRS were excluded. MRI scans for repeat treatments were fused with initial SRS plan. New lesions were outlined on the initial SRS planning CT. The mean dose that the site of new lesions received from initial SRS was tabulated. ResultsThirty-eight patients met inclusion criteria. 165 new lesions were evaluated. There was a lower propensity to develop new brain lesions with increasing dose received by the regions from prior SRS, with 66%, 34%, 19%, 13%, 6%, 5%, 2% and 1% of new lesions appearing in regions that received less than 1 Gy, greater than or equal to 1, 2, 3, 4, 5, 6, and 7 Gy, respectively. Higher doses are received by smaller brain volumes during SRS. After accounting for volume, 14, 14, 11, 7, 2, 2, 1 and 1 new lesions appeared per 100 cm3 of brain in regions that received doses of less than 1 Gy, greater than or equal to 1, 2, 3, 4, 5, 6, and 7 Gy, respectively, from prior SRS. ConclusionsWe identified low dose spillage during SRS to be associated with lower incidence of new brain metastases. Validation in larger dataset or prospective study of the combination of SRS with low dose WBRT would be crucial in order to establish causality of these findings.

Immune cell profiling of the cerebrospinal fluid enables the characterization of the brain metastasis microenvironment

Brain metastases are the most common tumor of the brain with a dismal prognosis. A fraction of patients with brain metastasis benefit from treatment with immune checkpoint inhibitors (ICI) and the degree and phenotype of the immune cell infiltration has been used to predict response to ICI. However, the anatomical location of brain lesions limits access to tumor material to characterize the immune phenotype. Here, we characterize immune cells present in brain lesions and matched cerebrospinal fluid (CSF) using single-cell RNA sequencing combined with T cell receptor genotyping. Tumor immune infiltration and specifically CD8+ T cell infiltration can be discerned through the analysis of the CSF. Consistently, identical T cell receptor clonotypes are detected in brain lesions and CSF, confirming cell exchange between these compartments. The analysis of immune cells of the CSF can provide a non-invasive alternative to predict the response to ICI, as well as identify the T cell receptor clonotypes present in brain metastasis.

Marital Stability and Quality of Couple Relationships after Acquired Brain Injury: A Two-Year Follow-Up Clinical Study.

Couple relationships after acquired brain injury (ABI) could be vulnerable to emotional distress. Previous evidence has demonstrated significant marital dissatisfaction in the first period after a traumatic event, while long-term evaluations are lacking. In this study, we evaluated the impact of a series of demographic and clinical factors on marital stability after two years from the injury. Thirty-five patients (29% female) with mild/moderate ABI (57% vascular, 43% traumatic) and their partners were enrolled. The couples completed a series of psychological questionnaires assessing marital adjustment (Dyadic Adjustment Scale, DAS) and family functioning (Family Relationship Index, FRI) at discharge from the intensive rehabilitation unit and after 2 years. Demographics (i.e., educational level, job employment and religion commitment) and clinical variables (i.e., the Barthel index, aetiology and brain lesion localization) were considered as predictive factors. Regression analyses revealed that the DAS and FRI values are differently influenced by demographic and clinical factors in patients and caregivers. Indeed, the highest educational level corresponds to better DAS and FRI values for patients. In the spouses, the variability of the DAS values was explained by aetiology (the spouses of traumatic ABI patients had worse DAS values), whereas the variability in the FRI values was explained by religious commitment (spending much time on religious activities was associated with better FRI values). Our data suggest that some clinical and demographic variables might be important for protecting against marital dissatisfaction after an ABI.

Detection of brain lesion location in MRI images using convolutional neural network and robust PCA

Purpose and aim: Detection of brain tumors plays a critical role in the treatment of patients. Before any treatment, tumor segmentation is crucial to protect healthy tissues during treatment and to destroy tumor cells. Tumor segmentation involves the detection, precise identification, and separation of tumor tissues. In this paper, we provide a deep learning method for the segmentation of brain tumors. Material and methods: In this article, we used a convolutional neural network (CNN) to segment tumors in seven types of brain disease consisting of Glioma, Meningioma, Alzheimer's, Alzheimer's plus, Pick, Sarcoma, and Huntington. First, we used the feature-reduction-based method robust principal component analysis to find tumor location and spot in a dataset of Harvard Medical School. Then we present an architecture of the CNN method to detect brain tumors. Results: Results are depicted based on the probability of tumor location in magnetic resonance images. Results show that the presented method provides high accuracy (96%), sensitivity (99.9%), and dice index (91%) regarding other investigations. Conclusion: The provided unsupervised method for tumor clustering and proposed supervised architecture can be potential methods for medical uses.

The Association of Early Electrocardiographic Abnormalities With Brain Injury Severity and Outcome in Severe Traumatic Brain Injury.

The aim of this study was to evaluate the frequency of electrocardiographic (ECG) abnormalities in the acute phase of severe traumatic brain injury (TBI) and the association with brain injury severity and outcome. In contrast to neurovascular diseases, sparse information is available on this issue. Data of adult patients with severe TBI admitted to the Intensive Care Unit (ICU) for intracranial pressure monitoring of a level-1 trauma center from 2002 till 2018 were analyzed. Patients with a cardiac history were excluded. An ECG recording was obtained within 24 h after ICU admission. Admission brain computerized tomography (CT)-scans were categorized by Marshall-criteria (diffuse vs. mass lesions) and for location of traumatic lesions. CT-characteristics and maximum Therapy Intensity Level (TILmax) were used as indicators for brain injury severity. We analyzed data of 198 patients, mean (SD) age of 40 ± 19 years, median GCS score 3 [interquartile range (IQR) 3–6], and 105 patients (53%) had thoracic injury. In-hospital mortality was 30%, with sudden death by cardiac arrest in four patients. The incidence of ECG abnormalities was 88% comprising ventricular repolarization disorders (57%) mostly with ST-segment abnormalities, conduction disorders (45%) mostly with QTc-prolongation, and arrhythmias (38%) mostly of supraventricular origin. More cardiac arrhythmias were observed with increased grading of diffuse brain injury (p = 0.042) or in patients treated with hyperosmolar therapy (TILmax) (65%, p = 0.022). No association was found between ECG abnormalities and location of brain lesions nor with thoracic injury. Multivariate analysis with baseline outcome predictors showed that cardiac arrhythmias were not independently associated with in-hospital mortality (p = 0.097). Only hypotension (p = 0.029) and diffuse brain injury (p = 0.017) were associated with in-hospital mortality. In conclusion, a high incidence of ECG abnormalities was observed in patients with severe TBI in the acute phase after injury. No association between ECG abnormalities and location of brain lesions or presence of thoracic injury was present. Cardiac arrhythmias were indicative for brain injury severity but not independently associated with in-hospital mortality. Therefore, our findings likely suggest that ECG abnormalities should be considered as cardiac mimicry representing the secondary effect of traumatic brain injury allowing for a more rationale use of neuroprotective measures.

Risk factors for hip dislocation in dyskinetic cerebral palsy.

To investigate the risk factors for hip displacement in patients with dyskinetic cerebral palsy (DCP). We evaluated 81 patients with DCP, 45 males and 36 females, aged 10-22 years, risk factors for hip displacement were evaluated using multivariate logistic regression analysis with primary brain lesions, Gross Motor Function Classification System (GMFCS) level, gestational age, birth weight, Cobb's angle, and complication of epilepsy as independent factors. Hip displacement was defined as migration percentage >30%. Primary brain lesions were classified into globus pallidus (GP), thalamus and putamen (TP), and others using brain magnetic resonance imaging (MRI). Perinatal and clinical features were compared between patients with GP lesions and those with TP lesions. Hip displacement was observed in 53 patients (67%). Higher GMFCS levels (p = 0.013, odds ratio [OR] 2.6) and the presence of GP lesions (p = 0.04, OR 16.5) were independent risk factors for hip displacement. Patients with GP lesions showed significantly higher GMFCS levels, more frequent hip displacement, and lower gestational age and birth weight than those with TP lesions. Primary brain lesion location may be an important factor in predicting hip displacement among patients with DCP. Appropriate risk assessment using brain MRI may contribute to the early detection and intervention of hip displacement because brain lesion location can be assessed during infancy before GMFCS level is decided.

Integrating Eye Tracking and Speech Recognition Accurately Annotates MR Brain Images for Deep Learning: Proof of Principle.

To generate and assess an algorithm combining eye tracking and speech recognition to extract brain lesion location labels automatically for deep learning (DL). In this retrospective study, 700 two-dimensional brain tumor MRI scans from the Brain Tumor Segmentation database were clinically interpreted. For each image, a single radiologist dictated a standard phrase describing the lesion into a microphone, simulating clinical interpretation. Eye-tracking data were recorded simultaneously. Using speech recognition, gaze points corresponding to each lesion were obtained. Lesion locations were used to train a keypoint detection convolutional neural network to find new lesions. A network was trained to localize lesions for an independent test set of 85 images. The statistical measure to evaluate our method was percent accuracy. Eye tracking with speech recognition was 92% accurate in labeling lesion locations from the training dataset, thereby demonstrating that fully simulated interpretation can yield reliable tumor location labels. These labels became those that were used to train the DL network. The detection network trained on these labels predicted lesion location of a separate testing set with 85% accuracy. The DL network was able to locate brain tumors on the basis of training data that were labeled automatically from simulated clinical image interpretation.© RSNA, 2020.

Stable complexes of neuropsychiatric symptoms in patients with vascular dementia with different localization of brain pathological focuses

The aim of the study was to determine the stable complexes of neuropsychiatric symptoms inherent in patients with vascular dementia with different localization of brain damage. 157 people with a diagnosis of vascular dementia were examined. Group 1 included 22 people with localization of the pathological process in the frontal lobe, group 2 — 18 patients with lesions of the temporal lobe, group 3 — 17 patients with lesions of the parietal lobe, group 4 — 15 patients with lesions of the occipital lobe, group 5 — 68 people with total defeat. All contingents are post-stroke patients over 50 years old, the average age is 68.12 years. Research methods: clinical-psychopathological, clinical-instrumental, experimental-psychological, anamnestic, clinical-statistical. The stable complexes (clusters) of neuropsychiatric symptoms inherent in patients with vascular dementia with different localization of brain lesions were determined. Revealing the following stable associations “localization — cluster”: frontal lobe — subpsychotic cluster (delusion — hallucinations — euphoria — agitation — depression); temporal lobe — asthenoanxiotic cluster (anxiety — irritability — agitation — sleep disturbances — apathy); parietal lobe — excitable-depressive cluster (depression — agitation — irritability — sleep disturbances); occipital lobe — affectocentric cluster (anxiety — depression — agitation — irritability); total defeat — asthenopathoideatoric cluster (apathy — irritability — agitation — anxiety — delirium). The identification of the association allows one to confidently determine the nature of the expected neuropsychiatric symptoms immediately after obtaining neuroimaging data regarding the localization of the lesion, which creates optimal conditions for the timely formation of a program of appropriate therapeutic interventions. Key words: vascular dementia, psychopathology, affective symptoms, neuropsychiatric symptoms, geriatric psychiatry

Understanding human individuation of unfamiliar faces with oddball fast periodic visual stimulation and electroencephalography.

To investigate face individuation (FI), a critical brain function in the human species, an oddball fast periodic visual stimulation (FPVS) approach was recently introduced (Liu-Shuang et al., Neuropsychologia, 2014, 52, 57). In this paradigm, an image of an unfamiliar "base" facial identity is repeated at a rapid rate F (e.g., 6Hz) and different unfamiliar "oddball" facial identities are inserted every nth item, at a F/n rate (e.g., every 5th item, 1.2Hz). This stimulation elicits FI responses at F/n and its harmonics (2F/n, 3F/n, etc.), reflecting neural discrimination between oddball versus base facial identities, which is quantified in the frequency domain of the electroencephalogram (EEG). This paradigm, used in 20 published studies, demonstrates substantial advantages for measuring FI in terms of validity, objectivity, reliability, and sensitivity. Human intracerebral recordings suggest that this FI response originates from neural populations in the lateral inferior occipital and fusiform gyri, with a right hemispheric dominance consistent with the localization of brain lesions specifically affecting facial identity recognition (prosopagnosia). Here, we summarize the contributions of the oddball FPVS framework toward understanding FI, including its (a)typical development, with early studies supporting the application of this technique to clinical testing (e.g., autism spectrum disorder). This review also includes an in-depth analysis of the paradigm's methodology, with guidelines for designing future studies. A large-scale group analysis compiling data across 130 observers provides insights into the oddball FPVS FI response properties. Overall, we recommend the oddball FPVS paradigm as an alternative approach to behavioral or traditional event-related potential EEG measures of face individuation.

Intracranial CT Scan Findings in the Patients of Head Injury: An Early Experience at Dera Ghazi Khan Teaching Hospital

Introduction: Head injury patients constitute a major number to any trauma emergency. Every head injury patient whose level of consciousness seems to alter, must be checked for brain injury. With the help of Computed Tomography (CT), Radiological evaluation has experienced a drastic change because it precisely explores the location and nature of lesion(s).
 Material and Methods: This study included 408 patients that were admitted to the emergency of Teaching Hospital Dera Ghazi Khan, from October 2017 to September 2019. In this study, the location as well as nature of lesions were evaluated with the help of CT.
 Results: CT results expressed that there was skull fracture (28.4%), extra dural hematoma (20.6%), diffuse intra cerebral hematoma (18.6%), brain contusions (18%), subdural hematoma (5.9%), diffuse axonal injury (DAI) (4.4%), subarachnoid hemorrhage (2.5%) and pneumocranium (1.5%). It was also noted that the males having age group between 20 – 35 years were mostly involved in head trauma and the reason for this was a road accident.
 Conclusion: CT scan explained the location and nature of brain and skull lesions.
 Keywords: Computed Tomography (CT), Road Accident, Head Trauma.

Weakly supervised object detection with 2D and 3D regression neural networks

Finding automatically multiple lesions in large images is a common problem in medical image analysis. Solving this problem can be challenging if, during optimization, the automated method cannot access information about the location of the lesions nor is given single examples of the lesions. We propose a new weakly supervised detection method using neural networks, that computes attention maps revealing the locations of brain lesions. These attention maps are computed using the last feature maps of a segmentation network optimized only with global image-level labels. The proposed method can generate attention maps at full input resolution without need for interpolation during preprocessing, which allows small lesions to appear in attention maps. For comparison, we modify state-of-the-art methods to compute attention maps for weakly supervised object detection, by using a global regression objective instead of the more conventional classification objective. This regression objective optimizes the number of occurrences of the target object in an image, e.g. the number of brain lesions in a scan, or the number of digits in an image. We study the behavior of the proposed method in MNIST-based detection datasets, and evaluate it for the challenging detection of enlarged perivascular spaces - a type of brain lesion - in a dataset of 2202 3D scans with point-wise annotations in the center of all lesions in four brain regions. In MNIST-based datasets, the proposed method outperforms the other methods. In the brain dataset, the weakly supervised detection methods come close to the human intrarater agreement in each region. The proposed method reaches the best area under the curve in two out of four regions, and has the lowest number of false positive detections in all regions, while its average sensitivity over all regions is similar to that of the other best methods. The proposed method can facilitate epidemiological and clinical studies of enlarged perivascular spaces and help advance research in the etiology of enlarged perivascular spaces and in their relationship with cerebrovascular diseases.

Which Brain Lesion Locations Differentiate Multiple Sclerosis (MS) from Neuromyelitis Optica Spectrum Disorders (NMOSD) and MOG Antibody Disorder (MOGAD)? (2399)

Which Brain Lesion Locations Differentiate Multiple Sclerosis (MS) from Neuromyelitis Optica Spectrum Disorders (NMOSD) and MOG Antibody Disorder (MOGAD)? (2399)

Neural substrates for poststroke complex regional pain syndrome type I: a retrospective case-control study using voxel-based lesion symptom mapping analysis.

Poststroke complex regional pain syndrome (CRPS) is characterized by swelling, pain, and changes in the skin that appear on the affected wrist and hand. In this retrospective study, we analyzed the relationship between poststroke CRPS and the location of stroke lesion. From all patients admitted to our hospital from 2009 to 2019, we recruited 80 patients affected by their first unilateral stroke who met the inclusion/exclusion criteria. Thirty-eight patients diagnosed with CRPS after stroke were assigned to the experimental group according to the "Budapest criteria" adopted by the International Association for the Study of Pain, and 42 patients without CRPS were included as controls. Regions of interest were manually drawn on T1-weighted magnetic resonance images, and data were normalized to a standard brain template. In the poststroke CRPS group, the relationship between the location of brain lesion and pain severity was analyzed using Freedman-Lane multivariable regression adjusting for Medication Quantification Scale rating, which was the only parameter to show a statistically significant correlation with pain intensity. A threshold of P < 0.01 was considered statistically significant for all voxel-based lesion symptom mapping tests, corrected for multiple comparisons with 5000 permutations. Analyses using voxel-wise subtraction and Liebermeister statistics indicated that the corticospinal tract (CST) was associated with the development of poststroke CRPS. Statistically significant correlations were found between pain intensity and the CST and the adjacent lentiform nucleus. Our results suggest that the CST may be a relevant neural structure for development of poststroke CRPS and the intensity of pain caused by the syndrome.

Determinants of long-term health-related quality of life in adult patients with mild traumatic brain injury.

Mild traumatic brain injury (mTBI) usually leads to the appearance of post-concussion symptoms (PCS) which may resolve after a short time. In this study, the mental and physical aspects of quality of life (QoL) were evaluated 6months after mTBI, and the association of demographic and injury-related factors, post-injury primary executive function and PCS types with the long-term QoL status was investigated. 123 eligible mTBI patients of initial sampling participated in follow-up phase of this longitudinal study. The demographic, clinical, and para-clinical data of patients were recorded. Paraclinical data comprised brain lesion volume, type and location determined by CT scan. The executive function and primary PCS were examined during the discharge using the verbal fluency task and a checklist, respectively. QoL was measured via SF-36 questionnaire. The collected data were entered into SPSS 22, and analyzed using appropriate statistical tests. Youngers aged between 18 and 35years and women had a lower QoL score than others. Primary somatic and cognitive PCS together were associated with poor QoL. There was no significant difference in QoL and executive function scores between the normal and abnormal brain CT groups. However, among people with abnormal CT, those having multifocal lesions including at least an intracranial hemorrhage type such as intra parenchymal hemorrhage or extra-axial bleeding together with other intracranial lesions or skull fracture demonstrated less QoL score in SF-36. A significant correlation was discovered between the scores of the executive function and QoL in mental dimensions of SF-36. This study emphasizes on the clinical significance of early executive function and PCS examination in mTBI population, as well as optimal management of the victims regardless of the initial brain CT findings, especially in high-risk populations.

Association between tumor location and neurocognitive functioning using tumor localization maps.

Patients with diffuse glioma often experience neurocognitive impairment already prior to surgery. Pertinent information on whether damage to a specific brain region due to tumor activity results in neurocognitive impairment or not, is relevant in clinical decision-making, and at the same time renders unique information on brain lesion location and functioning relationships. To examine the impact of tumor location on preoperative neurocognitive functioning (NCF), we performed MRI based lesion-symptom mapping. Seventy-two patients (mean age 40years) with a radiologically suspected glioma were recruited preoperatively. For each of the six cognitive domains tested, we used tumor localization maps and voxel-based lesion-symptom mapping analyses to identify cortical and subcortical regions associated with NCF impairment. Compared to healthy controls, preoperative NCF was significantly impaired in all cognitive domains. Most frequently affected were attention (30% of patients) and working memory (20% of patients). Deficits in attention were significantly associated with regions in the left frontal and parietal cortex, including the precentral and parietal-opercular cortex, and in left-sided subcortical fiber tracts, including the arcuate fasciculus and corticospinal tract. Surprisingly, no regions could be related to working memory capacity. For the other neurocognitive domains, impairments were mainly associated with regions in the left hemisphere. Prior to treatment, patients with diffuse glioma in the left hemisphere run the highest risk to have NCF deficits. Identification of a left frontoparietal network involved in NCF not only may optimize surgical procedures but may also be integrated in counseling and cognitive rehabilitation for these patients.

The association of brain lesion locations and sleep parameters in patients with multiple sclerosis: a pilot study

The relationship between sleep and brain lesions remains unknown in patients with multiple sclerosis (MS) and is currently under investigation. Sleep deprivation and reduction in the quality of sleep occur as a result of the direct involvement of the specific central nervous system structure. Therefore, we investigated the relationship between demyelination locations and sleep parameters such as sleep efficiency and respiratory disorders. The polysomnography measurements and brain magnetic resonance imaging (MRI) of 28 patients with relapsing–remitting MS were examined. The MRI results were evaluated using standardized maps to depict voxel-wise probability distribution of demyelination lesion load for patients. First, supratentorial and infratentorial lesion loads were evaluated. Subsequently, the procedure was completed by measuring the lobes and brainstem lesions loads in the brain. There was a negative correlation between the percentage of REM (%) and infratentorial and brainstem lesion loads ( $$\rho$$ : − 0.396, − 0.418; p 0.05). Although sleep-related breathing disorders are commonly seen in MS, this study shows that the polysomnography parameter most affected by brain lesion load distribution is REM sleep.

Focal neocortical lesions impair distant neuronal information processing.

Key points Parts of the fields of neuroscience and neurology consider the neocortex to be a functionally parcelled structure.Viewed through such a conceptual filter, there are multiple clinical observations after localized stroke lesions that seem paradoxical.We tested the effect that localized stroke‐like lesions have on neuronal information processing in a part of the neocortex that is distant to the lesion using animal experiments.We find that the distant lesion degrades the quality of neuronal information processing of tactile input patterns in primary somatosensory cortex.The findings suggest that even the processing of primary sensory information depends on an intact neocortical network, with the implication that all neocortical processing may rely on widespread interactions across large parts of the cortex. Recent clinical studies report a surprisingly weak relationship between the location of cortical brain lesions and the resulting functional deficits. From a neuroscience point of view, such findings raise questions as to what extent functional localization applies in the neocortex and to what extent the functions of different regions depend on the integrity of others. Here we provide an in‐depth analysis of the changes in the function of the neocortical neuronal networks after distant focal stroke‐like lesions in the anaesthetized rat. Using a recently introduced high resolution analysis of neuronal information processing, consisting of pre‐set spatiotemporal patterns of tactile afferent activation against which the neuronal decoding performance can be quantified, we found that stroke‐like lesions in distant parts of the cortex significantly degraded the decoding performance of individual neocortical neurons in the primary somatosensory cortex (decoding performance decreased from 30.9% to 24.2% for n = 22 neurons, Wilcoxon signed rank test, P = 0.028). This degrading effect was not due to changes in the firing frequency of the neuron (Wilcoxon signed rank test, P = 0.499) and was stronger the higher the decoding performance of the neuron, indicating a specific impact on the information processing capacity in the cortex. These findings suggest that even primary sensory processing depends on widely distributed cortical networks and could explain observations of focal stroke lesions affecting a large range of functions.

The relationship between ischaemic brain lesions and cognitive outcome after aneurysmal subarachnoid haemorrhage

BackgroundCerebral ischaemia is thought to be an important determinant of cognitive outcome after aneurysmal subarachnoid haemorrhage (aSAH), but the exact relationship is unclear. We studied the effect of ischaemic brain lesions during clinical course on cognitive outcome 2 months after aSAH.MethodsWe studied 74 consecutive patients admitted to the University Medical Center Utrecht who had MRI post-coiling (3–21 days post-aSAH) and neuropsychological examination at 2 months. An ischaemic lesion was defined as hyperintensity on T2-FLAIR and DWI images. We measured both cognitive complaints (subjective) and cognitive functioning (objective). The relationship between ischaemic brain lesions and cognitive outcome was analysed by logistic regression analyses.ResultsIn 40 of 74 patients (54%), 152 ischaemic lesions were found. The median number of lesions per patient was 2 (1–37) and the median total lesion volume was 0.2 (0–17.4) mL. No difference was found between the group with and the group without ischaemic lesions with respect to the frequency of cognitive complaints. In the group with ischaemic lesions, significantly more patients (55%) showed poor cognitive functioning compared to the group without ischaemic lesions (26%) (OR 3.4, 95% CI 1.3–9.1). We found no relationship between the number and volume of the ischaemic lesions and cognitive functioning.ConclusionsIschaemic brain lesions detected on MRI during clinical course after aSAH is a marker for poor cognitive functioning 2 months after aSAH, irrespective of the number or volume of the ischaemic lesions. Network or connectivity studies are needed to better understand the relationship between location of the ischaemic brain lesions and cognitive functioning.

Lesion Localization of Poststroke Lateropulsion.

Background and Purpose- Hemispheric stroke studies associating lateropulsion (pusher syndrome) with the location of brain lesions have had mixed results from small, unmatched samples. This study was designed to determine whether lateropulsion localizes to specific brain regions across patients with stroke using a case-control design. Methods- Fifty patients with lateropulsion after stroke were matched with 50 stroke patients without lateropulsion using age, time since onset of stroke, admission motor Functional Independence Measure score, lesion side, and gender. The primary analysis included multivariate lesion symptom mapping using sparse canonical correlations to identify regions most associated with lateropulsion as assessed with the Burke Lateropulsion Scale. Secondary analyses included evaluating paired comparisons for lesion volume, degree of motor impairment, motor and cognitive Functional Independence Measure scores. Results- The lesion symptom mapping analysis of all lesions mapped onto a common hemisphere produced an overall significant model ( P<5×10-5) with a regional peak at the inferior parietal lobe at the junction of the post-central gyrus (Brodmann Area 2) and Brodmann Area 40 as the lesion location most associated with lateropulsion. Lesion volume was larger for patients with lateropulsion. Despite adequate matching, motor performance and total Functional Independence Measure scores differed at a group level between patients with and without lateropulsion. Conclusions- This analysis implicated lesion involvement of the inferior parietal lobe as a key neuroanatomical determinant of developing lateropulsion. A better understanding of the anatomic underpinnings of lateropulsion may improve rehabilitation efforts, including the potential for informing noninvasive neuromodulation approaches.