Front | Back |
Possible results of partial volume?
|
1. decreased sharpness of edges2. misleading CT numbers
|
CT numbers ___ would appear black if window width of 400 and a window level of -100 are used.
|
Below -300
|
If a calcification with a CT number of +300 appears pure white on an image, the following could be the ww & wl selected
|
Window level = 0 window width = 500
|
_____ is the determinants of CT image quality, and is responsible for how grainy or speckled a CT image appears
|
Noise
|
If a thin slice is used the following would help reduce the apparent image noise?
|
Increased mAs
|
What controls the # of electrons that flow from the cathode to the anode in the tube
|
MA
|
What is an analog-to-digital converter?
|
The system component that converts the projection attenuation data into the proper digital form for the array processor
|
What determines the quantity of x-ray photons
|
MA
|
What is the main purpose of the detector?
|
To capture x-ray photons & convert them to a measurable signal
|
1) ____________ is accomplished by physically blocking x-rays.
|
Collimation
|
______ is the parameter that affects the contrast of a ct image.
|
Kvp
|
__________ is the parameter that is responsible for partial volume averaging.
|
Slice Thickness
|
What determines how penetrating the x-ray beam will be?
|
Kvp
|
_____ is the voltage potential between the tube cathode & anode while MA ultimately controls the filament current & thus the temp of cathode filament.
|
KV
|
What causes scatter radiation?
|
Deflections from the original trajectory of an x-ray photon through the pt
|