Ct Registry Ch8 Pt2

Front 1

What are the two different sources of tube arcing that can occur?

Back 1

Arcing within the tube

Arcing outside of the tube within the oil

Front 2

Arcing within the tube is caused as an x-ray tube begins to age. As the tube ages, _______________ builds up within the _______________ of the tube. As a result noise and streaks begin to appear on CT images. As the tube ages further the artifacts get worse.

Back 2

tungsten gas vapor

vacuum chamber

Front 3

Generally, arcing within the tube can be fixed by service personal by performing a procedure to "_______________" the gas

Back 3

burn off

Front 4

Arcing outside of the tube within the oil is typically caused when _______________ begins to collect in the oil which can create a(n) _______________ for the high voltage potential within the tube.

Back 4

air bubbles or other gases

electrically conductive path

Front 5

The current within the out of tube arc is so great it typically _______________ due to the excessive current.

Back 5

causes the high voltage generator to shut down

Front 6

When a(n) _______________ occurs, typically no images are created as no x-rays are produced.

Back 6

out of tube

Front 7

Artifacts due to tube arcing have no _______________ or _______________

Back 7

predictable pattern

regularity

Front 8

_______________ artifacts are associated with multi-row detector scanners that use only simple filtered back projection reconstruction.

Back 8

cone beam

Front 9

Cone beam artifacts cause peripherally located structures in the image to have a _______________ appearance.

Back 9

star-like

Front 10

Cone beam artifact is caused because x-ray photons spread along the Z-direction are not properly reconstructed with _______________.

Back 10

filtered back projection

Front 11

When x-ray beam collimation is greater than 20mm, or more than 4 slices are required in one rotation, the system needs to use _______________.

Back 11

cone beam reconstruction