Brain Perfusion Visual Analysis

Dzevdet Smajlovic, professor from the Department of Neurology at the University of Tuzla in Bosnia stated that

Due to this, it has been deemed difficult to determine which deficit is the consequence of which part of a lesion. To overcome this problem, other methods are being used to aid in the visualisation of memory processes in the healthy parts of the brain. These come in the form of functional neuroimaging studies using Positron Emission Tomography (PET) and Functional Magnetic Resonance Imaging (fMRI). These studies have allowed researchers to target specific memory processes using targeted psychological experiments. However, with all psychological experiments, there are limitations to using neuroimaging equipment. PET and fMRI attain their signals from local changes in blood flow or metabolism correlated with neural activity rather than from brain waves (or signals). The local vascular changes affect the distribution of an injected radionuclide (e.g. O15) in PET or magnetic properties that are blood-oxygen level dependent (BOLD) in fMRI. The indirect measure of neural activity limits the temporal and spatial fidelity of activations.

Using Functional MRI helps to visualize the brain functionality through local metabolism. In this technology it allows the researcher to measure and track the brain functions by discovering the correlated changes in blood flow. From this functional Mri when a brain function is acted out the flow of oxygenated rich blood is detected and highlighted on the specific location where the functionality came from on the brain.

Three main maps can be reconstructed from CTP data: cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT). Interpretation of the CTP maps is crucial in reversing functional damage and choosing the ideal treatment plan. Ischaemic brain tissue can be visualised in each map as regions of hypoperfusion within the brain tissue (Birenbaum et al., 2011; El-Koussy et al., 2014). Because CTP is a dynamic quantitative imaging technique, the percentage of brain damage can be calculated by measuring the mean values at the location of the same damaged tissue in the three maps. Moreover, the values for the damaged tissue are compared with those for normal tissue in the other, unaffected hemisphere. Finally, CBF is calculated by dividing CBV by MTT (Dorn et al.,

used to diagnose stroke and to determine the location and size of a brain tumor,

Measurements of diffusivity include fractional anisotropy and radial diffusivity. Fractional anisotropy (FA) and radial diffusivity (RD) are measurements of directionality of diffusion. A FA value of 0 represents unrestricted diffusion in all directions (isotropic) while a value of 1 represents diffusion along only one axis (anisotropic). Increased radial diffusivity is thought to represent a loss of myelin. Abnormalities on DTI are thought to reflect loss of white matter microstructural integrity, as seen in traumatic axonal injury. DTI is more sensitive for DAI than conventional MRI. DTI has shown that mTBI can be associated with widespread structural changes in cortical white matter tracts and the integrity of those have been shown to correlate with behavioral and cognitive measures. Changes in diffusivity indexes may indicate different types of white matter abnormality and different stages post injury after mTBI. Kou et al. reported that DTI fractional anisotropy (FA) can either decrease or increase in the acute setting. DTI FA values normally increase, and/or radial diffusivity (RD) decrease and/or apparent diffusion coefficient (ADC) decrease in the first week post-injury. Octavian et al. showed reduced FA on diffusion tensor imaging in the right superior longitudinal fasciculus in participants with mTBI31(Figure) More than 2 weeks post injury, either a

Resting-State functional MRI (rsfMRI) has been drawing increased attention (Biswal et al., 2010) and can be divided into two categories (Lee et al., 2013; Song et al., 2011). The first category is Resting-state functional connectivity (RsFC), which is a task-independent metric of brain activity that is primarily based on based on correlations between low-frequency fluctuations of the blood oxygen level dependent (BOLD) signal between disparate brain regions

In some of the professional athlete studies, for example, post-mortem examinations tend to demonstrate a complex series of changes that occurs not only in the gross anatomy of the brain but on the cellular level as well. The alteration of the anatomic and neurological structure often identifies CTE during autopsy through a series of markers, including an overall thinning of the corpus callosum, decrease in the average weight of the brain, enlargement of the ventricles, and significant atrophy of the brain, specifically in both frontal and temporal lobes (Edwards & Bodle, 2014). Furthermore, cellular level changes typically include alterations of both neuropil threads and neurofibrillary tangles, following a similar pathophysiology as that of Alzheimer’s disease and early onset dementia. The primary distinction between all of these conditions, however, is that the changes in CTE tend to affect multiple regions in the brain that are almost in equal in proportion and distribution (Edwards & Bodle,

Non-invasive mapping of connections between human thalamus and cortex using diffusion imaging: This article details a study that was performed using diffusion imaging characteristics to determine how pathways connect different parts of the brain. The study concluded that the pathway that is generated is based on the start point and the researchers developed and algorithm that could help them generate pathway within sections of the brain.

Clinical neuropsychologists evaluate patients using one of three general methods. The first method is to use an assessment technique in which a fixed battery of tests is given and in which we only want to know what functions are impaired and what functions are not impaired. The most commonly used representative of this type of test is the Halstead - Reitan Neuropsychological Battery. The second method is to use an assessment technique in which a fixed battery of tests is given but in this method there is a hierarchical arrangement of items within each subtest so that if a function is impaired, the level at which it is impaired can be determined. The most common representative of this type of test is the Luria - Nebraska.

Title: Evaluate experimental and brain-imaging techniques and consider what they tell us about the brain and cognitive behaviour in typical and atypical individuals.

Measuring the cerebral blood volume has always been a focal point of several neuroimaging studies in order to get a better understanding of the varied structure-function relationships within the human brain. Being one of the most complicated structures in the human body, the brain sits inside our head, protected by the skull and is made up of billions of neurons. The Cerebrum, cerebellum, and the brain stem, which turns into the spinal cord, are the three parts of the brain which are responsible for carrying out actions, thoughts, and maintaining hemostasis. (4) The cerebrum is divided into four parts: the frontal lobe, temporal lobe, parietal lobe, and the occipital lobe. While the frontal lobe is involved in one’s consciousness and thinking

These procedures involved in cognitive neuroscience require high levels of control, therefore are usually conducted in a laboratory setting, thus producing quantitative data that can be easily analysed, (Eysenck and Keane, 2010). Nevertheless, the techniques vary in the precision with which they identify the brain areas active when a task is performed (spatial resolution), and the time course of such activation (temporal resolution).Therefore, several procedures often need to be combined to compensate for limitations, (Sternberg and Wagner, 1999).

Variables of Interest: Our outcome variables of interest will be derived from the neuropsychological battery and spirometry tests. We will

In preparing large human brain sections for neuropathological study to have the best final result there needs to be the best initial preparation. Consequently the preservation of the specimen in the appropriate fixative promptly upon removal and changing the fixative when it becomes bloody greatly enhance specimen quality. Allow sufficient ratio of tissue to fluid of 1:20 and keep at room temperature. After the brain is sliced at brain cutting and the slabs are submitted for the large sections allow a day or two more in fixative for the center of the slice to be fixed. Patience will be rewarded. When processing the final blocks for paraffin, whether they