Karteikarten
Brain Imaging
Karten in diesem Stapel (13)
- 1What does CT stand for?Computerised Axial Temography
- 2How do CT scans work?They use thousands of narrow beam X-rays rotated around patient from different angles. Each beam is attenuated according to tissue densities. Different soft tissues can be identified.
- 3What are X Rays absorbed by?Dense materials
- 4What are some limitations/concerns with x-rays?Limited reslution so small structures can't be indentified. Ionising radiation that can be harmful to cells.
- 5What does MRI stand for?Magnetic resonance imagine
- 6What can an MRI be used for?Diagnosis of tumours, stroke, brain injury and infections
- 7How does an MRI work?Uses a magnetic field and radio waves to detect soft tissue. Magnetic field runs down tube, another field is superimposed. The combined fields causes axis and frequency of the spin of H nuclei to change, taking energy from the radio waves to do so. When the radio waves are turned off, H nuclei return to original alignment and release absorbed energy. This is detected and sent to a computed for an image.
- 8What does fMIR stand for?Functional magnetic resonance imaging
- 9What is a specific benefit of fMIR?Can produce information of the brain in action such as memory, emotion and consciousness.
- 10How does an fMIR work?It follows the uptake of O2 in activa areas. Deoxyhaemoglobin absorbs the radio waves but oxyhaemoglobin does not. Increased neural activity leads to increased oxygen demand thus increased blood flow. The less signal absorbed, the higher the level of activity
- 11If a subject persormes voluntary actions what areas of the brain would you expect to be active?The cerebellum as it coordinates movement as it is carried out. And motor cortex in the frontal lobe.
- 12What does the hypothalamus connect to?The pituitary Gland
- 13Where does the optic nerve pass through?Synapses in thalamus then the primary visual cortex