Compression Of Brain Tissue Research Articles

Comparison of the Results of Different Surgical Techniques in the Treatment of Chronic Subdural Hematoma in a Training and Research Hospital

Background: Chronic subdural hematoma can cause compression of brain tissue followed by neurological deficits. There are several methods for the treatment of chronic subdural hematoma, but the most appropriate treatment is still controversial. we compared 5 different surgical methods applied by five different surgeons in a single center and we suggest the most appropriate treatment method in the literature. Methods: In this study, the files of patients diagnosed with chronic subdural hematoma who underwent surgery at the Neurosurgery Clinic of S.B.U. Bursa City Hospital were retrospectively examined. The patients were evaluated in terms of their complaints, neurological examinations, type of operation, use of subdural drain and postoperative complications. Five different surgical techniques were applied to the patients. Results: We collected data from 185 patients who underwent surgery due to chronic subdural hematoma. Different surgical techniques were used in the treatment of patients. Only one burr hole was opened in 22 of the patients, one burr hole was opened in 40 of them and 1 drain was placed in the subdural space, only two burr holes were opened in 41 of them, two burr holes were opened in 58 of them and 1 drain was placed in the subdural space, and mini craniotomy was performed in 24 patients. Conclusion: Five different surgical methods used in the treatment of chronic subdural hematoma have advantages and disadvantages. We believe that a study conducted by increasing the number of patients, ensuring homogenization of groups, and increasing surgical techniques will shed light on the literature.

Intracranial hematoma segmentation on head CT based on multiscale convolutional neural network and transformer

AbstractIntracranial hematoma, a severe brain injury caused by trauma or cerebrovascular disease, can result in blood accumulation and compression of brain tissue. Untreated cases can cause headaches, impaired consciousness, and even brain tissue damage or death. Therefore, early and accurate diagnosis is crucial. Traditional segmentation methods require physicians with extensive clinical experience and expertise to manually mark out the hematoma region, but for hematoma cases with irregular shapes and uneven grey levels, this process is cumbersome, and the segmentation results are not good. Existing deep learning‐based methods are more likely to perform binary segmentation, considering all hematomas as a class and segmenting them, but this segmentation cannot capture more detailed information and lacks the analysis of different types of hematomas. To address these problems, an ICH segmentation network combining CNN and Transformer Encoder is proposed for accurate segmentation of different types of hematomas. The network incorporated edge information and long‐range context into the segmentation process. Experimental results using the CQ500 dataset demonstrate comparable performance to existing methods, with mIoU (0.8705), TPR (0.9273), mAP (0.9300), and DSC (0.9286) as the best metrics achieved by this paper's method.

Cdk5 mediates rotational force-induced brain injury

Millions of traumatic brain injuries (TBIs) occur annually. TBIs commonly result from falls, traffic accidents, and sports-related injuries, all of which involve rotational acceleration/deceleration of the brain. During these injuries, the brain endures a multitude of primary insults including compression of brain tissue, damaged vasculature, and diffuse axonal injury. All of these deleterious effects can contribute to secondary brain ischemia, cellular death, and neuroinflammation that progress for weeks, months, and lifetime after injury. While the linear effects of head trauma have been extensively modeled, less is known about how rotational injuries mediate neuronal damage following injury. Here, we developed a new model of repetitive rotational head trauma in rodents and demonstrated acute and prolonged pathological, behavioral, and electrophysiological effects of rotational TBI (rTBI). We identify aberrant Cyclin-dependent kinase 5 (Cdk5) activity as a principal mediator of rTBI. We utilized Cdk5-enriched phosphoproteomics to uncover potential downstream mediators of rTBI and show pharmacological inhibition of Cdk5 reduces the cognitive and pathological consequences of injury. These studies contribute meaningfully to our understanding of the mechanisms of rTBI and how they may be effectively treated.

Measurement and visualization of stimulus-evoked tissue dynamics in mouse barrel cortex using phase-sensitive optical coherence tomography.

We describe a method to measure tissue dynamics in mouse barrel cortex during functional activation via phase-sensitive optical coherence tomography (PhS-OCT). The method measures the phase changes in OCT signals, which are induced by the tissue volume change, upon which to localize the activated tissue region. Phase unwrapping, compensation and normalization are applied to increase the dynamic range of the OCT phase detection. To guide the OCT scanning, intrinsic optical signal imaging (IOSI) system equipped with a green light laser source (532 nm) is integrated with the PhS-OCT system to provide a full field time-lapsed images of the reflectance that is used to identify the transversal 2D localized tissue response in the mouse brain. The OCT results show a localized decrease in the OCT phase signal in the activated region of the mouse brain tissue. The decrease in the phase signal may be originated from the brain tissue compression caused by the vasodilatation in the activated region. The activated region revealed in the cross-sectional OCT image is consistent with that identified by the IOSI imaging, indicating the phase change in the OCT signals may associate with the changes in the corresponding hemodynamics. In vivo localized tissue dynamics in the barrel cortex at depth during whisker stimulation is observed and monitored in this study.

BSCI-10. NEUROLOGICAL DYSFUNCTION CAUSED BY BRAIN TUMOR-GENERATED SOLID STRESS IS REVERSED BY LITHIUM

The compression of brain tissue by a tumor mass is believed to be a major cause of the clinical symptoms seen in patients. However, the biological consequences of these physical stresses on the brain tissue are unknown. Using clinical imaging and preclinical studies, we discovered that a subgroup of primary and metastatic brain tumors, classified as nodular based on the growth pattern, exert compressive solid stress on the surrounding brain tissue, leading to a decrease in local vascular perfusion, as well as neuronal death and impaired function. We demonstrated a causal link between solid stress and neurological dysfunction, by applying and removing cerebral compression, mimicking the mechanics of tumor growth and surgical resection respectively. Finally, we showed that treatment with lithium reduced solid stress-induced neuronal death and improved motor coordination in mice. Our results indicate that brain tumor-generated solid stress impairs neurological function in patients and show lithium as a potential therapeutic intervention to counter these effects.

Stereotactic treatment of hypertensive intracerebral hemorrhage in basal ganglia region

Objective To evaluate the efficacy of stereotactic hematoma evacuation surgery for hypertensive cerebral hemorrhage in basal ganglia region. Methods A retrospective analysis was performed on 65 cases of hypertensive cerebral hemorrhage in the basal ganglia from August 2015 to March 2018 at the Stereotactic and Neurofunctional Center of the 306th Hospital of PLA. According to different surgical methods, those patients were divided into 2 groups. In the hematoma puncture group, 35 patients underwent hematoma puncture and drainage surgery; in the stereotaxis group, 30 patients underwent stereotactic puncture and catheter drainage surgery assisted by robot Remebot. The baseline conditions, bleeding time, volume of hematoma, preoperative GCS (Glasgow coma scale) score, Barthel score before discharge and at 3 months post operation, and the time of thorough hematoma drainage were compared between the 2 groups. Results (1) The time for thorough hematoma drainage in the stereotaxis group was significantly less than that in the hematoma puncture group. There was a significant difference between the 2 groups (Z=3.69, P<0.01). (2) Barthel scores before discharge (89.7±7.2) and at 3 months post operation (94.0±5.7) in stereotaxis group were significantly higher than those in hematoma puncture group (before discharge: 75.3±7.2, 3 months post operation: 76.4±8.2, both P<0.01). Conclusion Stereotactic hematoma evacuation surgery could significantly accelerate the removal time of hematoma in patients with hypertensive intracerebral hemorrhage, quickly relieve the compression of brain tissue by hematoma and promote the recovery of neurological function. Key words: Intracranial hemorrhage, hypertensive; Basal ganglia; Neurosurgical procedures; Stereotactic; Treatment outcome

Solid stress in brain tumours causes neuronal loss and neurological dysfunction and can be reversed by lithium.

The compression of brain tissue by a tumour mass is believed to be a major cause of the clinical symptoms seen in patients with brain cancer. However, the biological consequences of these physical stresses on brain tissue are unknown. Here, via imaging studies in patients and by using mouse models of human brain tumours, we show that a subgroup of primary and metastatic brain tumours, classified as nodular on the basis of their growth pattern, exert solid stress on the surrounding brain tissue, causing a decrease in local vascular perfusion as well as neuronal death and impaired function. We demonstrate a causal link between solid stress and neurological dysfunction by applying and removing cerebral compression, which respectively mimic the mechanics of tumour growth and of surgical resection. We also show that, in mice, treatment with lithium reduces solid-stress-induced neuronal death and improves motor coordination. Our findings indicate that brain-tumour-generated solid stress impairs neurological function in patients, and that lithium as a therapeutic intervention could counter these effects.

A teachable moment: Identifying hyperostosis frontalis interna in a gross anatomy cadaver laboratory

Hyperostosis frontalis interna (HFI) is a condition in which newly formed cancellous bone is deposited on the inner lamina of the cranium forming irregular thickening on the internal surface of the frontal bone. HFI is mostly considered as a benign entity; however, it may result in compression of brain tissue if the frontal bone is extensively hypertrophied. HFI may be associated with hormonal imbalance and/or neuropsychiatric abnormalities, such as behavioral disturbances and dementia. Although, the etiology of HFI remains largely unknown, there is marked female predominance as HFI has been frequently reported among postmenopausal elderly women, and is reported in males with severe hypogonadism and testicular atrophy. Here, we report a case of an 80 year-old woman who was diagnosed with Alzheimer’s disease/vascular dementia at the time of death, and was found to have HFI with dural fusion during dissection in the human gross anatomy laboratory at Gannon Universityt.

The Relationship between Intracranial Pressure Increase and Volume of Brain Compression

Objective: The physiological background for intracranial pressure, ICP, increase at brain compression is presently unknown. Current knowledge of the relationship between ICP and volume of brain compression is based on animal experiments, which has led to the theory of elastic brain tissue compression, which like a loaded spring causes the ICP increase. However, tests of brain tissue composition, or compression, find no basis for elasticity, or compression. The aim of this article is to describe the physiological features controlling ICP since it is necessary for the understanding of intracranial physiology, but also since ICP is an important parameter in neurointensive care medicine. Methods: This evaluation is based on the physiological consequences of the closed intracranial compartment, the thin-walled, compressible venous bed, the auto-regulation of cerebral blood flow, CBF, to blood pressure changes, and the coupling between ICP and the intra-capillary blood pressure through the thin, flexible capillary wall. These features influence the intracranial venous blood volume, the venous vascular resistance, and the CBF. Together these features are shown to revile the ICP dependence on the volume of brain volume compression. Results: The evaluation leads to a formula that describes the relationship between ICP and changes in the brain volume. The formula predicts an exponential ICP increase at brain compression like in animal experiments but, contrary to the elastic tissue theory, a gradually higher exponential for larger compression. Conclusion: The found relationship between ICP and changes in brain volume may prove to be a useful tool in neuro-intensive care patients for following changes in intracranial volumes by the aid of continuous ICP measurements. Since brain-compressing volumes includes the arterial pulse volume, the ICP formula may also enable CBF calculation from ICP measurements. The physiological relationships leading to the description of the relationship between ICP and brain volume change may by themselves help in understanding other intracranial phenomena, like ICP plateau-waves.

An efficient approach for brain image (tissue) compression based on the position of the brain tumor

Medical image processing plays an important role in brain tissue detection and segmentation. In this paper, a computer aided detection of brain tissue compression based on the estimation of the location of the brain tumor. The proposed system detects and segments the brain tissues and brain tumor using mathematical morphological operations. Further, the brain tissue with tumor is compressed using lossless compression technique and the brain tissue without tumor is compressed using lossy compression technique. The proposed method achieves 96.46% sensitivity, 99.20% specificity and 98.73% accuracy for the segmentation of white matter regions from the brain. The proposed method achieves 98.16% sensitivity, 99.36% specificity and 98.78% accuracy for the segmentation of cerebrospinal fluid CSF regions from the brain and also achieves 93.07% sensitivity, 98.79% specificity and 97.63% accuracy for the segmentation of grey matter regions from the brain. This paper focus the brain tissue compression based on the location of brain tumor. The grey matter of the brain is applied to lossless compression due to the presence of the tumor in grey matter of the brain. The proposed system achieves 29.23% of compression ratio for compressing the grey matter of the brain region. The white matter and CSF regions of the brain are applied to lossy compression due to the non-presence of the tumor. The proposed system achieves 39.13% of compression ratio for compressing the white matter and also achieves 37.5% of compression ratio for compressing the CSF tissue. © 2016 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 26, 237-242, 2016

In Vivo Investigation of the Effectiveness of a Hyper-viscoelastic Model in Simulating Brain Retraction.

Intraoperative brain retraction leads to a misalignment between the intraoperative positions of the brain structures and their previous positions, as determined from preoperative images. In vitro swine brain sample uniaxial tests showed that the mechanical response of brain tissue to compression and extension could be described by the hyper-viscoelasticity theory. The brain retraction caused by the mechanical process is a combination of brain tissue compression and extension. In this paper, we first constructed a hyper-viscoelastic framework based on the extended finite element method (XFEM) to simulate intraoperative brain retraction. To explore its effectiveness, we then applied this framework to an in vivo brain retraction simulation. The simulation strictly followed the clinical scenario, in which seven swine were subjected to brain retraction. Our experimental results showed that the hyper-viscoelastic XFEM framework is capable of simulating intraoperative brain retraction and improving the navigation accuracy of an image-guided neurosurgery system (IGNS).

Abstract T P45: Automated CSF Segmentation to Quantify Cerebral Edema Following Large Hemispheric Ischemic Stroke

Introduction: Cerebral edema with resultant mass effect is a potentially fatal consequence of ischemic stroke, but early and sensitive biomarkers of brain tissue compression are lacking. To quantify brain mass effect, we developed a novel, automated segmentation method to delineate CSF spaces in CT images from ischemic stroke patients. Methods: CTs from sixteen acute ischemic stroke patients (median NIHSS 16.5, median age 61.5 yrs, 14-92 hrs after stroke onset) were included after informed consent was obtained. After infarction, conventional CSF segmentation using Hounsfield unit (HU) thresholding is suboptimal due to infarct hypodensity. Utilizing manually delineated infarct and CSF spaces as training samples, we augmented conventional HU threshold segmentation with level sets, sparse regression and random forest segmentation methods. Using leave-one-out cross-validation, the combined approach was compared to HU thresholding using Dice ratios (a measure of the overlap between the segmented and the ground-truth CSF spaces). Results: Shown is an example of a CT brain slice segmented by HU thresholding and the combined strategy: false negative (red), false positive (green), and true positive (yellow). The Dice ratios for HU thresholding and the combined approaches were 58.2±16.3% and 68.9±14.6%, respectively, demonstrating the significantly improved performance for the combined strategy (p=0.0014). Conclusions: We have developed an advanced image segmentation strategy to delineate CSF spaces which outperforms conventional HU thresholding. An automated CSF segmentation strategy will permit quantification of cerebral edema in a large population of stroke patients, as required for genetic studies, for example.

Elevated diffusion anisotropy in gray matter and the degree of brain compression

For several decades, clinicians have predicted intraparenchymal brain pressure or brain tissue compression indirectly based on the degree of distortion of the midline structures (midline shift) and ventricle wall (ventriculomegaly) observed on conventional MRI. However, this method has several limitations. Diffusion tensor imaging (DTI) is a novel MRI technique that can provide information about the microstructural properties of compressed tissue. In this study, the authors evaluated whether DTI can precisely define the degree of tissue compression in patients with chronic subdural hematoma (CSDH). The study sample consisted of 18 patients (mean age 71 years, 10 men and 8 women) with unilateral CSDH and 12 age-matched volunteers. Diffusion tensor imaging results were acquired before and after the surgical irrigation in the CSDH group. Subdural pressure during the operation was also measured. Fractional anisotropy (FA) values were evaluated at several locations, including the gray matter. The FA values of the gray matter, especially in the caudate nucleus and putamen, were increased in the patients with CSDH compared with the control group. The change in FA data before and after surgery (ΔFA) correlated with the degree of tissue compression evaluated by measurement of the subdural pressure. Furthermore, the increased FA values in patients with CSDH decreased after surgery. These findings indicate that FA values of the gray matter, especially in the caudate nucleus and putamen, may be important markers of tissue compression. The assessment of FA values of the gray matter will result in a new, less-invasive diagnostic technique to evaluate the degree of brain compression.

Determination of friction coefficient in unconfined compression of brain tissue

Unconfined compression tests are more convenient to perform on cylindrical samples of brain tissue than tensile tests in order to estimate mechanical properties of the brain tissue because they allow homogeneous deformations. The reliability of these tests depends significantly on the amount of friction generated at the specimen/platen interface. Thus, there is a crucial need to find an approximate value of the friction coefficient in order to predict a possible overestimation of stresses during unconfined compression tests. In this study, a combined experimental–computational approach was adopted to estimate the dynamic friction coefficient μ of porcine brain matter against metal platens in compressive tests. Cylindrical samples of porcine brain tissue were tested up to 30% strain at variable strain rates, both under bonded and lubricated conditions in the same controlled environment. It was established that μ was equal to 0.09±0.03, 0.18±0.04, 0.18±0.04 and 0.20±0.02 at strain rates of 1, 30, 60 and 90/s, respectively. Additional tests were also performed to analyze brain tissue under lubricated and bonded conditions, with and without initial contact of the top platen with the brain tissue, with different specimen aspect ratios and with different lubricants (Phosphate Buffer Saline (PBS), Polytetrafluoroethylene (PTFE) and Silicone). The test conditions (lubricant used, biological tissue, loading velocity) adopted in this study were similar to the studies conducted by other research groups. This study will help to understand the amount of friction generated during unconfined compression of brain tissue for strain rates of up to 90/s.

Giant atypical intraventricular meningioma presenting with visual loss in a child

Giant atypical intraventricular meningioma is very rare in childhood. Atypical meningiomas are characterised by an increased mitotic ratio and MIB-1 expression, and demonstrate more aggressive tumour behaviour compared with typical meningiomas. We present the case of an 11-year-old girl who presented to the eye clinic complaining of reduced vision, and was diagnosed with a giant atypical intraventricular meningioma. Five years after surgical resection, there has been no recurrence of the tumour. Goldmann visual fields show a left incongruous homonymous hemianopia. This case highlights the importance of ophthalmic examination in diagnosing brain tumours in children. Such a large tumour located in the lateral ventricle may cause obstructive hydrocephalus, compression of brain tissue, seizures and loss of vision, and is potentially fatal.

Mathematical Modeling of CSF Pulsatile Hydrodynamics Based on Fluid–Solid Interaction

Intracranial pressure (ICP) is derived from cerebral blood pressure and cerebrospinal fluid (CSF) circulatory dynamics and can be affected in the course of many diseases. Computer analysis of the ICP time pattern plays a crucial role in the diagnosis and treatment of those diseases. This study proposes the application of Linninger et al.'s [IEEE Trans. Biomed. Eng., vol. 52, no. 4, pp. 557-565, Apr. 2005] fluid-solid interaction model of CSF hydrodynamic in ventricular system based on our clinical data from a group of patients with brain parenchyma tumor. The clinical experiments include the arterial blood pressure (ABP), venous blood pressure, and ICP in the subarachnoid space (SAS). These data were used as inputs to the model that predicts the intracranial dynamic phenomena. In addition, the model has been modified by considering CSF pulsatile production rate as the major factor of CSF motion. The approximations of ventricle enlargement, CSF pressure distribution in the ventricular system and CSF velocity magnitude in the aqueduct and foramina were obtained in this study. The observation of reversal flow in the CSF flow pattern due to brain tissue compression is another finding in our investigation. Based on the experimental results, no existence of large transmural pressure differences were found in the brain system. The measured pressure drop in the ventricular system was less than 5 Pa. Moreover, the CSF flow pattern, ICP distribution, and velocity magnitude were in good agreement with the published models and CINE (phase-contrast magnetic resonance imaging) experiments, respectively.

Pulsatile Cerebrospinal Fluid Dynamics in the Human Brain

Disturbances of the cerebrospinal fluid (CSF) flow in the brain can lead to hydrocephalus, a condition affecting thousands of people annually in the US. Considerable controversy exists about fluid and pressure dynamics, and about how the brain responds to changes in flow patterns and compression in hydrocephalus. This paper presents a new model based on the first principles of fluid mechanics. This model of fluid-structure interactions predicts flows and pressures throughout the brain's ventricular pathways consistent with both animal intracranial pressure (ICP) measurements and human CINE phase-contrast magnetic resonance imaging data. The computations provide approximations of the tissue deformations of the brain parenchyma. The model also quantifies the pulsatile CSF motion including flow reversal in the aqueduct as well as the changes in ICPs due to brain tissue compression. It does not require the existence of large transmural pressure differences as the force for ventricular expansion. Finally, the new model gives an explanation of communicating hydrocephalus and the phenomenon of asymmetric hydrocephalus.

Dolichoectatic Intracranial Arteries: Review of Selected Aspects

Dolichoectasia of intracranial arteries may cause a variety of neurological problems including cranial nerve and brain tissue compression, hydrocephalus, and cerebral ischemia. Different mechanisms ma

Chapter 57: Aspects of normal cerebrospinal fluid circulation and circumventricular organs

Publisher Summary Uptake into circumventricular organs (CVOs) of horseradish peroxidase (HRP) administered into blood vessels was first demonstrated with the electron microscope in 1968. CVOs and the remainder of the brain gave rise to the idea that the extravasated HRP must be reabsorbed together with the cerebrospinal fluid (CSF) into fenestrated venous capillaries of the same CVOs. Otherwise, as Evans blue in the bloodstained CVOs, extravasated plasma protein would stain the whole brain. On the other hand, arachnoid villi or granulations are believed to be the sites of drainage into the venous system of the CSF, even though these structures are ontogenetically as well as phylogenetically limited to some adult higher mammals. Experimental data strongly suggest that: (1) routes for CSF to drain into the blood circulation are fundamentally through fenestrated venous capillaries of CVOs; (2) arachnoid granulations prevent a sudden CSF pressure rise, which could cause noxious compression of brain tissue; and (3) arachnoid granulations play a role in the immune response.