Neuro Unit 3 Diagnostics

  1. What are the two types of brain imaging techniques? What are they used for? Give examples.

    What are electrophysiologic studies used for? Give examples.
    • 1. Structural: To look at shape of brain for abnormalities or if damage is present; dx of strokes, tumors, AVM); cerebral angiography, CT/CAT, MRI
    • 2. Functional: To look at brain activity and see if part of brain is still working; what parts of the brain are used for certain tasks; certain parts of the brain when active: utilizing O2 and blood flow; examines blood flow for examining parts of the brain that are active during a task; PET, SPECT, fMRI

    To look at the duration and sequence of activity in the brain; EEG, MEG, ERP, EMG
  2. Cerebral Angiography
    Invasive or noninvasive?
    What is it used for?
    How does it work?
    • Invasive
    • Looks at the shape of the artery; uses X-ray to view the picture
    • A radiopaque substance is injected into artery/vein that absorbs x-rays less or more than surrounding tissue
  3. Computed axial tomography (CAT/CT)
    Uses x-ray beams, which are affected by the ___ of the tissue through which it passes, to produce _____.

    Brain lesions such as ___, ___, ___, are visible as areas of high-density, appears ___, or low-density, appear ___. 

    Lesions associated with hemorrhage or aneurysm shows as an area of ___-density.
    An infarct/swelling shows as an area of __-density. 
    Blood & bone are ___-density; tissues are __-density
    • density, image of the brain
    • CVA, TBI, tumor
    • white; dark
    • high, low
    • high, low
  4. Magnetic Resonance Imaging (MRI)
    Constructed from measurement of waves that ___ atoms emit when activated within a magnetic field.

    Reveals differences in ___ content between different tissues.

    Pathologic areas (CVA, TBI, tumors, myelination) are __, or increase in signal intensity.
    • hydrogen
    • water
    • bright
    • *Bone contains little water, few signals=less visible
  5. Functional Magnetic Resonance Imaging (fMRI)
    Provides images of brain __ and __.
    Function imaged by detecting changes in local blood __, __, and __ saturation.
    Advantages
    Invasive or noninvasive? 
    Radiation risk? 
    How is the image quality?
    Used primarily in clinic or research?
    • Structure and function
    • volume, flow, oxygen
    • noninvasive, low risk, superior
    • research
  6. Electroencephalography
    measures duration and sequence of ___ ___ in the brain. 
    What is it used to diagnose?
    Used in research or clinically?
    Disadvantage?
    • electrical activity
    • seizures, tumors, head injuries, degenerative diseases, brain death
    • Both
    • only measures activity in cortex, not deeper
  7. Evoked potentials (ERP)
    Measures electrical activity in response to a __, __, or __ stimulus.
    Multiple responses are averaged and the data are called __-__ or ___ ___.
    • auditory, visual, somatosensory
    • event-related, evoked potential
    • *Measures how long an activity occurred
  8. Electromyography
    Measures electrical activity during ___.
    What is examined to diagnose nerve or muscle diseases?
    • Movement
    • Quality, speed, magnitude of electrical impulses
Author
janessamarie
ID
253002
Card Set
Neuro Unit 3 Diagnostics
Description
Overview of diagnostic techniques
Updated