Misc from Quizzes Flashcards
What is important to the image quality of an x-ray?
density, sharpness, distortion, exposure time
What is the most radio lumescent?
air (allows the x-ray beam to pass through them since it is not dense)
Computed tomography is x-rays that are compiled by a ______
into cross sectional images of the body that are relatively free from _______ of the different tissues.
computer, suprimposition
CT slices are not axial but _____.
helical
Projections from the CT provide sufficient data to calculate the radiodensities for each cubic _______ or less within each slice
millimeter
CT myelography is best to use for what purpose?
injection of contrast may identify postoperative Spinal stenosis
The cone beam of a CT scan is best used for what?
shorter scanning time for things like wrist and hand
The produce of the pixel and slice thickness is called a
voxel
A single voxel may contain different tissues.
When multiple tissues are in a single voxel, the computer performs _____ averaging can result in loss of _____ resolution.
volume, contrast
Ideal viewing position for an axial CT
viewed as if the patient is in supine looking caudocephalad (upwards)
-Back (Posterior) of the section is at the Bottom of the image
Ideal viewing position for an sagittal CT
viewed from L to R
Ideal viewing position for a coronal CT
front to back as if the patient is facing the clinician
Things that degrade a CT
movement, too thick a slice, and metals
Pathologies ideal for a CT scan
loose bodies in a joint, complex fractures, trauma/multiple injuries, degenerative changes (such as spinal stenosis)
forms of radiography (x-ray) using the same mechanism of ionizing radiation
CT and fluroscopy
