Basic Principles/CT
Tomography means:
The contrast agent commonly used for MRI exams is:
Gadolinium
Name the 3 meningeal membranes:
Dura Mater, Arachnoid mater and Pia Mater
CT number for water is:
Zero
Voxel
Why is the term CAT scan no longer used?
Axial refers to one particular plane through the body. Today's CT technology can reconstruct images in virtually any plane
What nuclei found in the body is the most abundant and most often used in MRI
Name the 3 divisions of the brain:
Forebrain, Midbrain and Hindbrain
Pitch is defined as:
the ratio between couch speed and slice thickness
Commonly used as a cooling material for MRI magnets:
Cryogen
How many generations of scanners are there?
1st through 4th
With modern MRI, the reemitted radio wave signals from the patient are captured by:
receiver/antenna/coil
Interpretation center for sensory impulses such as pain, temperature, and touch certain emotions and memory.
Thalamus
This generation of CT scanners had a fan shaped beam, rotated 180 degrees around the patient, and could scan 40 slices in 10 minutes
Second
Twisting movement of ferromagnetic objects in MRI
Torque
The gantry can be angled how many degrees in each direction?
30 degrees
This type of imaging technique collects MRI signals at a specific point during the respiratory or cardiac cycle to avoid motion artifact:
Gating
Largest of the cranial nerves: Name and Number
V- trigeminal
What specifically do the CT detectors measure:
attenuation
Quantity of hydrogen nuclei present in tissue
Spin density
The CT number for fat is:
How does it appear on an image:
-100
dark grey
With this type of relaxation, the MRI signal decreases 37% from maximum value and the transition results in the nuclei being out of phase:
T1
optic chiasma
Window level determines what:
the CT number that will be center of window width
Process where a spinning object is acted on by an outside force and it starts to tilt or wobble
Precession