Why is low concentratoin of barium used for CT studes?
to prevent beam hardening
What is teh hole in the middle of the gantry called?
aperature
T/F: The first CT scanner was designed to image the head only?
True
What is the significane of slip ring technology?
Continous rotation of the x-ray tube to get rid of the cord=pathways for helical scanning
The ratio between patient couch movement and x-ray beam collimations is defined as?
pitch
What are teh five steps in the CT process?
acquisition
restruction
display
maniuplation
storage
How can CT dose me minimized?
reduce # of slices, shielding, increase slice thickness
What are the undesirable results of over sampling?
increased dose
An image used for localization that resembles a conventional radiograph created with stationary CT tube and detectors ans patient movement is called?
scout (tomogram, scanogram)
Why is contrast media necessary for a CT study of the abdomen and pelvis?
to be able to diagnose the unpacified portions of the small and large bowels, they may be misdiagnosed as lymph nodes absesses or masses=deliniate between the tissues
What are the requirements to become board eligible in CT?
Registered Tech
clinical compitency (125 exams out of 9 catagories)
Pass an exam (education)
Why is MRI the modality of choice for soft tissue imaging?
allows increased contrast resolution at molecular level.
What is the significance of the primary magnet and how does it relate to image quality?
B0=creates static magnetic field-stronger magnet more protons align to it. better the image
What are the advantages and disadvantages of permanent primary magnets?
Low operating cost
heavy
low strength
What is the biggest advantage assocaiated with a resistive primary magnet?
it can be shut off
Which type of primary magnet is the most common? what are teh advantages and disadvantages of this type of magnet?
Supraconductive
A: fast and increased test load
D: does not shut off and costy
What are the advantages and disadvantages of open MRI scanners?
A: Helps with closterfobic patiens
D: Low field and decreased quality images (depending on the tech)
What is the loud thumping noise heard during an MRI scan?
Gradients switching back and forth
______is used to study blood vessels and is a less invasive alternative to angiography?
MRA
______is used to determine which part of the brain is handling certain functions?
fMRI
What are several contraindications of MRI?
pacemaker, ferromagnet aneurism clips, mettalic fragments in the eye, choclear implant, bone growth stimulators, neurostimulators, pregnancy
What are the two options for certification in MRI?
-primary certification only
-registered tech+clinical experience within 24 mo
Compare T1and T2?
T1= looks like x-ray-low contrsat
T2= used for pathology
What is resonance?
same energy in order to transfer
6 components of MRI?
What is the last line you are able to pass when having anything metal in a MRI room called?
five gows line
Nuclear medicine uses radioactive material called______in the study and treatment of various medical conditions?
radiopharmaceutical
Radioactive materials that are introduced in the body and concentrate in specific organs are called____? and how are these materials introduced into the body?
Tracer= inhaled injected oral
What is the most commonly used radionuclide?
technetium 99 M (Tc-99m)
T/F: The purose of a nuclear medicine study is primary to evaluate the structure of the area of interest?
False
The term SPECT is an abbreviation for what?
Single photon emission computed tomography
The SPECT gamma camera provides a _____dimensional view of the anatomy?
3D
A study of the skeletal system using radioactive materials is called?
Bone Scan
A common genitourninary nuclear medicine study is perfomred for____?
Kidney Transplant
What radiopharmaceuticals are used during myocardial perfusion studies?
Thalume, cardiolite
What radiopharmaceutical is used to determine if a pulmonary lesion is benighn or malignant?
neotect
The perfusion phase of a lung study is used to detect____?
pulmonary embolism
What radiopharmaceutical is used in a thyroud uptake study?
sodium iodine
A hyperthyroid will result in a ____ uptake reading and may indicate____disease?
increase, grave
A hypothyroid will result in a ____uptake reading?
decrease
The term PET is an abbreviation for what?
positron emission tomography
PET uses radioactive compounds that emit____?
Positron
What do the detectors of a PET scannner detect?
gamma radiation=annilation
What are the common positron emitting elements?
oxygen, nitrogen, chlorlide
F-FDG is used to measure what?
glucose
O-water i used to measure what?
blood flow/perfusion of blood
N-ammonia is used to measure what?
blood flow/ perfusion of blood
C-methionine is used to measure what?
Amino Acid Metabolism
A____is used to produce the radioactive tracer close to cyclotron?
Cyclotron
For oncology applications, what properties of a tumore does PET scaning rely on?
glucose uptake (sugar metabolism)
For cardiology applicatoins_____is given to evaluate heart perfusions and_____is given to evaluate glucose metabolism?
Amonia thalium; FFG
How is PET used to evaluate seizure sites in epilepsy patients regardless of whether they are having a seizure at the time of the scan?
Will be a increase in sugar uptake (with seizure sugar uptake will be normal or decrease)
What is the purpose of brain mapping?
vital areas of brain functioning
What is the advantage of using amino acid metabolism for characterizing CNS tumors?
