Q&A / Already Graded A, 2025/2026.
Terms in this set (503)
Increasing the CT image High-contrast spatial resolution
matrix from 256x256 to
512x512 will likely improve?
What is the smallest pixel
The practicaloflimiting
component spatial
a digital 1.4 mm
resolution of a CT scanner is
image
3.6 lp/cm. What size object
does this correspond to?
How many CT numbers are One
assigned to each pixel in the
image matrix?
Use of a bone filter, as Spatial resolution
In a CT image,
opposed to athe CT tissue
soft Of a material is dependent on its linear attenuation coefficient
number
filter, to reconstruct CT
images would likely
Each two-dimensional
improve? pixel
square of data that make up
the CT image is called a
The spatial resolution of a 1 mm
typical CT scanner is on the
order of?
What is an element of the pixel
digital image
A 512 x 512 matrix CT 8.5
image over a 30-cm field of
Which of the following *detector size
view could show a spatial
influences the spatial *reconstruction interval
resolution of no better than
resolution in cardiac CT
? lp/cm? *pitch
imaging
When
As comparing
patient motion aincreases Contains four times as many pixels: 1024 x 1024
TRUE
512x512
spatial matrix todecreases
resolution a =1048576 then 512 x 512= 262144...then divide 1048576
1024x1024 matrix, the /262144 = 4
1024x1024 matrix?
Which is an advantage of increased spatial resolution
using a small focal spot
, Biannually
High contrast spatial
resolution and low contrast
resolution are typically
measured baseline and ?
thereafter
To improve the high contrast Matrix size (128x128 to 512x512)
spatial resolution of a CT
study, one would increase
_____ while keeping all
other factors the same.
A radiologist wants to Increase the matrix size
improve the high-contrast
spatial resolution of
anatomy which he/she is
examining by CT. The change
which would best lead to
this improvement is
To improve the highcontrast Matrix size
spatial resolution of a CT
study, one could increase ?
while keeping all other
factors the same?
A voxel contains 25% air, 0
50% water and 25% bone.
The CT number for this
voxel would be expected to
be _____ HU?
How many pixels are D. 1,048,576
contained in a 1,024 matrix
image?
MATH 1024 X1024
, pixel
It is located in a matrix and
is a two dimensional
representation of a voxel
When CT numbers are pixel
calculated for voxels (volume
elements) of tissue what is
assigned the calculated
number and a subsequent
shade of gray
What is defined as a picture pixel
element or the smallest
component of the digital
image
A CT scan produces a 0.6 equation: 30cm/512= .058cm convert to mm and its
512x512 matrix transverse .58 which is approximately 0.6
image of a 30 cm diameter
FOV. Each pixel is
approximately _____ mm on
a side.
The ability of a system to spatial resolution
define small objects
distinctly is referred to as
which of the following?
Which of the following terms *spatial resolution
is/are commonly used to *sensitivity
describe a CT scanner's ability
to differentiate objects with
similar linear attenuation
coeffiecents
, Which of the following *patient size
factors have an affect on *slice thickness
contrast resolution
*pixel size
*mAs/dose
FALSE
As mAs/dose increases
contrast resolution
decreases
As mAs/dose increases TRUE
contrast resolution
INCREASES
The ability of a CT scanner to *contrast resolution
accurately image objects *sensitivity
with similar densities is
termed
Which of the following has a *mAs/dose increase
direct relationship on *Slice thickness
increasing contrast resolution
For a particular CT scanner's 50. Equation (.21-.20/.21) × 1000= 50
beam quality, the linear
attenuation coefficient for
water is 0.20 cm-1 and for a
certain tumor is 0.21 cm-1.
What is the CT number of
the tumor?
A CT scanner with poor tissues whose linear attenuation coefficients are nearly
contrast resolution or low equal
sensitivity has difficulty
separating
What is the basic physical Linear attenuation coefficient
quantity being measured by
a CT system