Equations

Question 1

How do you find pixel size?

Answer 1

Pixel size=POV/Matrix size

Question 2

What is the equation for remnant radiation in CT scanners?

Answer 2

Ni=N0e-ux
Ni=radiation that comes out
N0=Radiation that comes in
x=slice thickness

Question 3

How do you find the voxel value?

Answer 3

1. Measured value-Assumed value
2. Divide this number between the 2 voxels present
3. Continue at another angle until the 4 values add up to the measured value

Question 4

How do you calculate pitch, and pitch isn SDCT?

Answer 4

Ptich=Couch movement each 360 degrees/beam width

(same for SDCT)

Question 5

How do you find beam width in MDCT?

Answer 5

Beam width=Slice thickness x number of slices

Question 6

How do you calculate volume imaged?

Answer 6

Volume imaged=Pitch x beam width x imaging time/rotation time

Question 7

How do you find the CT number?

Answer 7

CT number=u-uw/uw (1000)

Question 8

How do you find beam width in SDCT?

Answer 8

Beam width=slice thickness

Question 9

How do you find voxel size?

Answer 9

Voxel size=Pixel size x slice thickness or LWH

Question 10

How do you find the number of neutrons?

Answer 10

Atomic mass-atomic number

Question 11

What is the Larmor Equation?

Answer 11

Question 12

What is the equation to find radioactivy activity?

Answer 12

A(t)=amount you ended up with
A0=Initial amount
λ=Decay constant
t=Time

Question 13

What is the equation to find Radioactive Half Life?

Answer 13

Nt = N0 e^-λt

Question 14

What is the equation for radioactivy decay?

Answer 14

⋋ = 0.693/T1/2
OR
A(t) = ⋋ x N(t)

Question 15

How do you find the Acoustic velocity (c)?

Answer 15

f x λ

Question 16

What is 1MHz equal to in Hz?

Answer 16

1000000

Question 17

How do you find reflection fraction?

Answer 17

(Z2-Z1)/(Z2+Z1)

z=impedance