How Do Imaging Of The Brain?

○ History and physical examination is suggestive of disease by explicit clinical criteria (i.e., hypertension, sudden onset of seizure, neurologic deficits, coma)·

     If doctors agree that a stroke has taken place, they may do other tests to determine where the stroke occurred, how large of an area is damaged, and how the blood flow with in the brain has been effected; they do this by taking a CAT scan. They may also take an ECG to determine if there is any heart disease that may have caused the stroke. In addition, they take tests to see if the patient has high blood pressure or they may test the arteries themselves because this is a major cause of stroke in most people. Catheterization, injecting dye into the arteries, and blood tests are the most common tests done. A high glucose level in the blood may reveal diabetes and high blood fats indicate thickened red blood and arteriosclerosis. There may also be a high level of red blood cells, changing the consistency of the blood. These conditions must be treated to prevent further strokes.

According to our American Red Cross Nursing Assistant text a cerebral vascular accident, C.V.A., or stroke occurs when blood flow to a part of the brain is interrupted. The loss of blood supply results in the death of brain cells. (Page 91) When your brain starts to die the bodily functions the brain controls can be affected. The affected bodily functions depend on what part of the brain does not receive oxygen. Web MD says damage “can occur within 3-4 minutes if not treated.”

Strokes are caused by pathophysiological changes. The two major mechanisms of stroke consist of ischemia and haemorrhage. Ischemia is when there is no oxygen or not, merely enough oxygen to fuel the tissue level in the body. Haemorrhage in the brain, causing strokes can be due to non-traumatic intracerebral haemorrhage (Shah, MD, n.d.) (see appendix 1). This essay will further discuss the implications of strokes on a cellular, organ and system level. Explain the clinical presentation of the signs and symptoms of strokes and how the condition will be managed by a paramedic.

The next step is to do tests on the brain itself to rule out other possible conditions. Doctors will often do a CT scan first, then an MRI, and possibly a PET scan; these tests will show abnormalities of the brain, and they will help rule out tumors, clots, or if the patient has had a stroke.

The diagnostic process for a formally diagnosing Cerebral Vascular Accident (CVA/stroke), would consist with a number of test including a physical exam and questions regarding your family history of strokes, any signs or symptoms that may have been present before the patient had the stroke. The physician would also order a few tests like a MRI, CT scan, Cerebral Carotid ultrasound, Cerebral Angiogram and an Echo Cardiogram. The physical exam is important to listen to the hearts sounds, take your blood pressure and also use a ophthalmoscope ( a scope to look in your eyes, ears and nose) to see if there are any cholesterol crystals behind the eyes("Diagnosis - Stroke - Mayo Clinic," 2015). A MRI, uses radio and magnetic waves to show a detailed

Then, to check if the brain has suffered damage, if deemed necessary, the doctor will take a CT scan of the brain. The doctor will look for evidence of bleeding under the skull or within the brain tissue.

A myth that many people believe is that humans only use ten percent of their brain. One reason why so main people believe this is because it has been pushed by many psychics or any paranormal pushers because if science can't explain it psychic powers can. Brain imaging such as PET scans, show that the majority of the brain is used at one point or another. Driving, for example, uses literally all of the brain to process everything that is being done.

A stroke is a condition which is characterised as loss of brain functioning due to an interruption in the blood flow to the brain (Buzzard, 2013, pg. 5). There are two types of strokes, ischaemic and hemorrhagic strokes (Buzzard, 2013, pg. 6). Ischaemic strokes are the most common type of stroke (Gomes & Wachsman, 2013). This type of stroke occurs due to an insufficient flow of blood to the brain, which is usually caused by an artery blockage (Gomes & Wachsman, 2013). Hemorrhagic strokes are due to hypertension and may be caused by medical problems or blood vessel abnormalities (Gomes & Wachsman, 2013). The strokes severity and location of the brain that is affected determines the impact of the stroke in an individual (Gomes & Wachsman, 2013).(Gomes, 2013)

Given the absence of a clinical test to accurately distinguish between haemorrhagic and ischaemic strokes, imaging at this early stage is vital. A non-contrast CT brain is often performed at this point although when unavailable, MRI is usually more sensitive and specific in identifying stroke lesions at the cost of longer examination times (Vymazal, Rulseh, Keller & Janouskova, 2012).

A Computed Tomography (CT) can be used to inspect large hemorrhages, that could be surgically excised, but in case of small hemorrhages, it is insensitive. Small hemorrhages could be early contusions or diffuse axon injury (DAI). SWI comes handy in determining such small hemorrhages and intracranial microhemmorhages. It is a high-resolution, fully velocity compensated, 3-dimensional gradient echo imaging sequence that is extremely sensitive to blood products in hemorrhage and deoxyhemoglobin in venous blood. Normally, CT and MRI would spot traumatic hemorrhagic lesions in cortical gray matter (GM), sub cortical white matter (WM), major white matter tracts, including corpus callosum and internal capsule, brainstem and in the ventricles. SWI helps in localizing microhemmorhages lesions at GM/WM junction. The research paper explores about a comparison of SWI and a conventional GRE performed by Tong et al. The outcome of it was a difference in lesion counts, which was highest in the brainstem/cerebellum and corpus callosum, while, lowest in the frontal & parietal-temporal-occipital GM/WM. The research article also reviews a study by Wu et al about patients with subarachnoid hemorrhage (SAH) using CT and SWI. The

Hemorrhagic stroke occurs when a blood vessels in the brain leaks or ruptures. Bleeding from the ruptured brain artery can either go into the substance of the brain or into the various spaces surrounding the brain. The two types of hemorrhagic stroke are Intracerebral and Subarachnoid hemorrhagic.

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

Magnetic resonance imaging has the potential of totally replacing computed tomography. If history was rewritten, and CT invented after MRI, nobody would bother to pursue CT. --Philip Drew (Mattson and Simon, 1996)

Neurologically, trauma to the brain can be seen as bleeding or swelling. Other abnormalities often found include: brain aneurysms, stroke, tumors of the brain, as well as inflammation of the spine. In addition, Neurosurgeons use an MRI scan not only for analyzing the brain anatomy but also in evaluating the structure of the spinal cord after trauma. It is also used when considering problems associated with the vertebrae or intervertebral discs in the spine. Finally, an MRI scan can also evaluate the structure of the heart and aorta, to detect aneurysms or tears.