Neuro Imaging Flashcards
CT/ CAT scans accepted imaging for what?
imaging modality for evaluation of the entire body
CT/ CAT scan uses?
Thousands of narrow beam x rays that pass at different angles
CT/ CAT scan looks at?
Structures rather than functions
Attenuated data is summed up from thousands of angles used in a process called
reconstruction
Can small structures be seen in CT/CAT?
nope
what is used to detect brain diseases
CT/ CAT Scan
contrast dye can be used in CT/CAT scans for?
detect organs
On CT/CAT scan Bones are
white
On CT/CAT scan gases and liquids are?
black
On CT/CAT scan tissues are?
gray
Tomographic image ?
picture of a slab of the pt’s anatomy
what does MRI stand for
Magnetic Resonance Imaging
MRI magnetic field is ________ times as strong as earth’s magnetic fields
60,000x
Atom that MRI uses?
hydrogen
What is the resonance bit for MRI
Nuceli are hit by pulsing radio waves, this RF makes the protons spin at a particular frequency, in a particular direction
MRI diagnosing
MS, Stroke, infections of the brain/ spine/ CNS, Tendonitis
MRI visualizing
Injuries, torn ligaments
MRI evaluating
Masses in soft tissues, cysts, bone tumors or disc problems
Advantages of MRI
- Does not use Ionizong radiation
- Contrast dye has low chance of side effects
- Non invasive
- Provides comparable resolution with far better contrast resolution (ability to distinguish the differences between two arbitrarily similar but not identical tissues)
Contraindications of MRI
- Pacemaker
- Metal objects in body
Top two MRI images
T1WI & T2WI
T1WI detects water and fluid containing tissues as
DARK
T1WI detects fat containing tissues as
Bright
T2WI detects water & fluid containing tissues as
Bright
T2WI detects fat containing tissues as
DARK
T1WI are used more for
Fluid, swelling, blood
T2WI are good at finding
Pathology
what does MRA stand for ?
Magnetic Resonance Angiography
What are MRA used for?
- images blood vessels
- stenosis & aneurysms
fMRI is done when?
while pt performs a task
fMRI is
functional
fMRI displays
Metabolically active tissue,
fMRI utilizes oxygen uptake as a measure of
brain activity
Strengths of fMRI
- Non-invasive, replicable
- Potentially good spatial localization
- Common, well-validated technique
Limitations of fMRI
- Mediocre temporal resolution (seconds)
- Complex, highly variable data analyses
- Expensive and time-consuming
what detects electrical activity in the brain?
EEG
What diagnosing EPILEPSY
EEG
What is used to diagnose sleeping disorders
EEG
what 3 ares does EEG help identify intervention
- lobectomy
- Cortical excision
- Hemispherectomy
Lobectomy
removes part of the lobe of a brain (temporal)
Cortical excision
removes outer layer of the cortex
hemispherectomy
remove outer layer and anterior temporal lobe on one half of the brain
What injects Tracers?
PET scan
PET scans detects
Glucose metabolism, cancer, dementia, seizures, map brain function
Strengths of PET scan
- Uses a simple physiological mechanism
- Provides absolute, quantitative data
- Allows imaging of anything that can be tagged
Limitations of PET Scan
- Poor temporal resolution (many minutes)
- Poor spatial resolution (several centimeters)
- Requires injection of radioactive material
