Part D: Fundamentals Flashcards
- In the equation associated with Larmor Equation, B₀ stands for:
a. Static magnetic field
b. Frequency
c. Gyromagnetic ratio
d. Voltage
a. Static magnetic field
- In the equation associated with Larmor Equation, ω₀ stands for:
a. Static magnetic field
b. Frequency
c. Gyromagnetic ratio
d. voltage
b. Frequency
- In the equation associated with Larmor Equation, y stands for:
a. Static magnetic field
b. Frequency
c. Gyromagnetic ratio
d. voltage
c. Gyromagnetic ratio
- A magnetic field strength of 0.5T is equivalent to:
a. 15 000 G
b. 5 000 G
c. 1 G
d. 10 000G
b. 5 000 G
- A condition whereby there are MORE spins ‘in line’ with the magnetic field than ‘opposed’ is known as:
a. Low energy
b. High energy
c. Thermal equilibrium
d. Excitation
c. Thermal equilibrium
- During thermal equilibrium there are:
a. More spins in the low energy state
b. More spins in the high energy state
c. Equal number spins in the low and high energy state
d. Less spins in the low energy state
a. More spins in the low energy state
- Proton spins that are ‘in line’ with the static magnetic field (B₀) are referred to as all of the following EXCEPT:
a. Spin up
b. Parallel
c. Low energy spins
d. High energy spins
d. High energy spins
- The microscopic magnetic field associated with the proton within the magnetic field is known as the:
a. Free induction decay (FID)
b. Magnetic moment (μ)
c. Signal echo (SE)
d. Field of view (FOV)
b. Magnetic moment (μ)
- During thermal equilibrium, the vector that represents the ‘spin excess’ is known as the:
a. Free induction decay (FID)
b. Net magnetisation vector (NMV)
c. Signal echo (SE)
d. Field of view (FOV)
b. Net magnetisation vector (NMV)
- The RF pulse is applied to achieve a condition known as:
a. Thermal equilibrium
b. Excitation
c. Relaxation
d. Scan timing
b. Excitation
- During excitation, all of the following occur EXCEPT:
a. Low energy spins enter the high energy state
b. Spins begin to precess ‘in phase’
c. The net magnetisation is transferred into the transverse (x/y) plane
d. High energy spins return to the low energy state
d. High energy spins return to the low energy state
- During relaxation, all of the following occur EXCEPT:
a. Low energy spins enter the high energy state
b. High energy spins return to the low energy state
c. Spins begin to precess ‘out of phase’ or lose phase coherence
d. The net magnetisation recovers longitudinally
a. Low energy spins enter the high energy state
- T1 relaxation is also known as all of the following EXCEPT:
a. T1 recovery
b. Spin lattice
c. Longitudinal recovery or relaxation
d. Spin-spin
d. Spin-spin
- T2 relaxation is also known as:
a. T1 recovery
b. Spin lattice
c. Longitudinal recovery or relaxation
d. Spin-spin
d. Spin-spin
- T2 relaxation is also known as all of the following EXCEPT:
a. T2 decay
b. Spin lattice
c. Spin-spin
d. Transverse relaxation
b. Spin lattice
- T1 relaxation tim eis define as when:
a. 76% of the longitudinal magnetisation has regrown
b. 63% of the longitudinal magnetisation has regrown
c. 63% of the transverse magnetisation has regrown
d. 76% of the transverse magnetisation has regrown
b. 63% of the longitudinal magnetisation has regrown
- T2 relaxation tim ei sdefined as when:
a. 76% of the longitudinal magnetisation has regrown
b. 63% of the longitudinal magnetisation has regrown
c. 63% of the transverse magnetisation has regrown
d. 76% of the transverse magnetisation has regrown
c. 63% of the transverse magnetisation has regrown
- Images acquired with a spin echo pulse sequence having a SHORT TR and TE values yield images known as (Figure D.1):
a. T1W1
b. T2WI
c. PDWI
d. Diffusion images
a. T1W1
(Figure D.1):
- Images acquired with a spin echo pulse sequence having LONG TR and TE values yield image known as (Figure D.1):
a. T1W1
b. T2WI
c. PDWI
d. Diffusion images
b. T2WI
(Figure D.1):
- Images acquired with a spin echo pulse sequence having LONG TR an SHORT TE values yield images known as (Figure D.1):
a. T1W1
b. T2WI
c. PDWI
d. Diffusion images
c. PDWI
(Figure D.1):
- Spin density is another term for (Figure D.1):
a. Nuclear density
b. Spin density
c. Proton density
d. b and c
b. Spin density
(Figure D.1):
- Spin density is determined by the (Figure D.1):
a. Amount of excess spins in the low energy state at equilibrium
b. Amount of transverse magnetisation at the time the echo is sampled
c. T1/T2
d. Amount of excess spins in the high energy state equilibrium
a. Amount of excess spins in the low energy state at equilibrium
(Figure D.1):
- Gradient echo (steady-state) sequences acquired with short TR and flip angle combinations along with a moderately long TE yield images with (Figure D.1):
a. T1 contrast
b. T2 contrast
c. PF contrast
d. T2* contrast
d. T2* contrast
- T2 + T2’ equals (Figure D.1):
a. T1
b. T2
c. PD
d. T2*
d. T2*
- The LOGICAL gradient that is used for slice selection for the acquisition of an axial slice is the:
a. x
b. y
c. z
d. A combination of gradients
c. z