Imaging Flashcards
Who invented computed tomography in 1971?
Sir Godfrey Hounsfield
A simple imaging modality that consists of an x-ray tube that emits photons differentiating organ specific densities within a patient.
CT scan
CT tube potential unit of measurement
kilovolt peaks (kVp)
Photon counts unit of measurement
milliamperes (mA)
3 elements required for acquisition of high fidelity cardiac and coronary CT images
Spatial resolution
Temporal resolution
Volume coverage
These elements improves the spatial resolution of CT scan to approx 230 micron in-plane resolution
Garnet and phosphorus
Software-based postprocessing technique used to correct coronary motion artifacts by exploiting the trajectory data across time and “backtracking” to create motion-free images
Intracycle motion correction algorithms
Improvements in volume coverage by imaging greater lengths in the z axis, or craniocaudal direction, have been achieved by increases in the number of detector rows is also termed as..
Volumetric CT imaging
It is a requirement for cardiac CT scanning for imaging acquisition at a motion-free period within the cardiac cycle that optimizes visualization of coronaries
ECG gating
It is a threshold measure, above which harm can occur and below which it does not
Deterministic Risk
Give an example of deterministic risk
Skin burn
It is the potential of radiation to increase risk at any level of exposure, for example, CANCER.
Stochastic risk
It is a measurement of the total radiation dose absorbed by a patients body and is typically reported in gray (Gy) or radiation absorbed dose (rad) units.
CTDI - ct dose index
It is the unit that represents the biological effects of imparted radiation weighted relative to the orgab that is exposed to radiation.
Sieverts (Sv)
Full radiation doses are imparted in this part of cardiac cycle during CT imaging
Diastole
