ARMRIT review test questions with verified detailed answers || || || || || || ||
The exact middle of the bore of the magnet is termed: - correct answer✔✔Isocenter
|| || || || || || || || || || || || ||
Without proper safety limits on the MR system exposure to the time-varying magnetic fields
|| || || || || || || || || || || || ||
created by the rapid switching of the gradient could create a potential environment for: -
|| || || || || || || || || || || || || || || ||
correct answer✔✔Including electrical current in the patient's tissues
|| || || || || || ||
Faraday's Law deals with induction of a current by a magnet. true or false? - correct
|| || || || || || || || || || || || || || || ||
answer✔✔true
The orientation of the main magnetic field of a low field permanent magnet is vertical. True
|| || || || || || || || || || || || || || ||
or false? - correct answer✔✔True ; permanent lowfield magnets utilize a magnetic field
|| || || || || || || || || || || || || ||
oriented vertically ||
Superconductive magnets have high homogeneity compared to other magnets types. true or || || || || || || || || || || || ||
false? - correct answer✔✔true ; One advantage of a superconductive magnet is its excellent
|| || || || || || || || || || || || || ||
homogeneity
The start up cost for a superconductive magnet is high. true or false? - correct
|| || || || || || || || || || || || || || ||
answer✔✔true ; Initial cost may exceed two million dollars in addition to the expensive|| || || || || || || || || || || || || ||
cyrogen up keep. || ||
A type of magnet that is generally used for a 1.0t or a 1.5t system is a: - correct
|| || || || || || || || || || || || || || || || || || ||
answer✔✔Superconductive magnet ||
The basic type of magnets used in MR are: - correct answer✔✔Permanent, resistive ,
|| || || || || || || || || || || || || ||
superconductive
,A procedure called shimming: - correct answer✔✔Adjust the magnetic field to achieve the
|| || || || || || || || || || || || ||
most homogenous field || ||
Superconductive magnets utilize two types of cyrogens. - correct answer✔✔Helium and || || || || || || || || || || ||
nitrogen
Types of transmit coils are: - correct answer✔✔a) Body, b) head, c) volume coils, d) all of
|| || || || || || || || || || || || || || || || ||
the above. D all of the above
|| || || || || ||
Various types of receiver coils are: - correct answer✔✔a) solenoidal coil, b)
|| || || || || || || || || || || ||
volume,birdcage,surface coil, c) Helmholtz pair coil, d) All of the above: D all of the coils || || || || || || || || || || || || || || || ||
are true receiver coils
|| || ||
To gain SNR and gain high resolution: - correct answer✔✔Use a small surface coil
|| || || || || || || || || || || || ||
Which of the following is not an example of a surface coil: - correct answer✔✔body coils
|| || || || || || || || || || || || || || || ||
are not surface coils
|| || ||
In a cross-sectional view of the magnet bore, which set of coils are the closest to the bore? -
|| || || || || || || || || || || || || || || || || || ||
correct answer✔✔RF coil- the cross sectional of the MR system reveals the order of
|| || || || || || || || || || || || || ||
thecoils: the magnet bore, then the RF coils, Then the gradient coils, then the shim coils &
|| || || || || || || || || || || || || || || || ||
the outer most are magnet coils.
|| || || || ||
MR systems can be shielded by two processes. They are: - correct answer✔✔Passive and
|| || || || || || || || || || || || || ||
active shielding ||
The more expensive type of shielding that uses additional solenoid magnets outside the
|| || || || || || || || || || || || ||
cyrogen bath that restricts the magnetic field line to an acceptable location is the: - correct
|| || || || || || || || || || || || || || || ||
answer✔✔Active- passive shielding can be accomplished by lining the walls with steel || || || || || || || || || || || ||
while the more expensive alternative is active shielding
|| || || || || || ||
,Surface coils are connected inside the scanner by cables. These cables shouldnt touch the
|| || || || || || || || || || || || || ||
patient because: - correct answer✔✔They could burn the patient.
|| || || || || || || ||
Quadrature design coils give you a lower SNR. true or false? - correct answer✔✔True:
|| || || || || || || || || || || || || ||
Quadrature coil designs improve SNR due to increased coverage. || || || || || || || ||
The two coils in a magnet used to transmit RF are the shim and tune coils. true or false? -
|| || || || || || || || || || || || || || || || || || || ||
correct answer✔✔False: transmit coils are usually the body and head coils.
|| || || || || || || || || ||
Magnetic field gradients are generated by what? - correct answer✔✔coils of wire situated
|| || || || || || || || || || || || ||
within the bore of the magnet.
|| || || || ||
In the event of a cryogenic leak or catastrophic magnet quench, the first thing the
|| || || || || || || || || || || || || || ||
technologist should do is? - correct answer✔✔evacuate all persons from the scan room.
|| || || || || || || || || || || ||
The given field strength (ex..1.5T) of the magnet is maintained at the: - correct
|| || || || || || || || || || || || || ||
answer✔✔Middle od the axis of the bore, middle of the axis reamins at the field strength. || || || || || || || || || || || || || || ||
When employing a surface coil the signal intensity: - correct answer✔✔decreases as
|| || || || || || || || || || || ||
anatomy gets further from the coil. || || || || ||
Surface coils are "receive only" coils. true or false? - correct answer✔✔False
|| || || || || || || || || || ||
The largest possible receiver coil should be chosen: true or false? - correct answer✔✔False-
|| || || || || || || || || || || || || ||
optimally smallest coils are best || || || ||
, Surface coils are free standing & have no electrical components. true or false? - correct
|| || || || || || || || || || || || || || ||
answer✔✔false
The precessonial frequency of hydrogen at 1.5T is 68MHz. true or false? - correct
|| || || || || || || || || || || || || ||
answer✔✔False- Hydrogen @1.5T is 63.86MHz || || || ||
What happens to the precessional frequency of those protons which experience a higher
|| || || || || || || || || || || || ||
magnetic field? - correct answer✔✔It increases
|| || || || ||
To achieve the shortest scan time possible, which of the following would not be selected. -
|| || || || || || || || || || || || || || || ||
correct answer✔✔Shortest TE possible. TE doesnt effect scan time
|| || || || || || || ||
In a 2DFT scan using a TR of 1 second, a TE of 30msec, a FOV 24, Matrix 128 & 2 NSA.
|| || || || || || || || || || || || || || || || || || || || || ||
What is your total scan time for 1 slice? - correct answer✔✔4.2 minutes; 1x128x2/60=4.2
|| || || || || || || || || || || || ||
In MR , the frequency of water is_________ as compared to the frequency of fat. - correct
|| || || || || || || || || || || || || || || || ||
answer✔✔Higher- The frequency in H2O is higher than fat || || || || || || || ||
The following statement: Any signal must be sampled at least twice per cycle in order to
|| || || || || || || || || || || || || || || ||
represent or reproduce it accurately; is a mathematical principle called: - correct
|| || || || || || || || || || || ||
answer✔✔Nyquist Theorem ||
If the Nyquist theorem is not adhered to in the MR experiment what is the result? - correct
|| || || || || || || || || || || || || || || || || ||
answer✔✔Aliasing
At equilibrium more nuclear spines are________ with the magnetic field. - correct
|| || || || || || || || || || || ||
answer✔✔In Alignment ||
The exact middle of the bore of the magnet is termed: - correct answer✔✔Isocenter
|| || || || || || || || || || || || ||
Without proper safety limits on the MR system exposure to the time-varying magnetic fields
|| || || || || || || || || || || || ||
created by the rapid switching of the gradient could create a potential environment for: -
|| || || || || || || || || || || || || || || ||
correct answer✔✔Including electrical current in the patient's tissues
|| || || || || || ||
Faraday's Law deals with induction of a current by a magnet. true or false? - correct
|| || || || || || || || || || || || || || || ||
answer✔✔true
The orientation of the main magnetic field of a low field permanent magnet is vertical. True
|| || || || || || || || || || || || || || ||
or false? - correct answer✔✔True ; permanent lowfield magnets utilize a magnetic field
|| || || || || || || || || || || || || ||
oriented vertically ||
Superconductive magnets have high homogeneity compared to other magnets types. true or || || || || || || || || || || || ||
false? - correct answer✔✔true ; One advantage of a superconductive magnet is its excellent
|| || || || || || || || || || || || || ||
homogeneity
The start up cost for a superconductive magnet is high. true or false? - correct
|| || || || || || || || || || || || || || ||
answer✔✔true ; Initial cost may exceed two million dollars in addition to the expensive|| || || || || || || || || || || || || ||
cyrogen up keep. || ||
A type of magnet that is generally used for a 1.0t or a 1.5t system is a: - correct
|| || || || || || || || || || || || || || || || || || ||
answer✔✔Superconductive magnet ||
The basic type of magnets used in MR are: - correct answer✔✔Permanent, resistive ,
|| || || || || || || || || || || || || ||
superconductive
,A procedure called shimming: - correct answer✔✔Adjust the magnetic field to achieve the
|| || || || || || || || || || || || ||
most homogenous field || ||
Superconductive magnets utilize two types of cyrogens. - correct answer✔✔Helium and || || || || || || || || || || ||
nitrogen
Types of transmit coils are: - correct answer✔✔a) Body, b) head, c) volume coils, d) all of
|| || || || || || || || || || || || || || || || ||
the above. D all of the above
|| || || || || ||
Various types of receiver coils are: - correct answer✔✔a) solenoidal coil, b)
|| || || || || || || || || || || ||
volume,birdcage,surface coil, c) Helmholtz pair coil, d) All of the above: D all of the coils || || || || || || || || || || || || || || || ||
are true receiver coils
|| || ||
To gain SNR and gain high resolution: - correct answer✔✔Use a small surface coil
|| || || || || || || || || || || || ||
Which of the following is not an example of a surface coil: - correct answer✔✔body coils
|| || || || || || || || || || || || || || || ||
are not surface coils
|| || ||
In a cross-sectional view of the magnet bore, which set of coils are the closest to the bore? -
|| || || || || || || || || || || || || || || || || || ||
correct answer✔✔RF coil- the cross sectional of the MR system reveals the order of
|| || || || || || || || || || || || || ||
thecoils: the magnet bore, then the RF coils, Then the gradient coils, then the shim coils &
|| || || || || || || || || || || || || || || || ||
the outer most are magnet coils.
|| || || || ||
MR systems can be shielded by two processes. They are: - correct answer✔✔Passive and
|| || || || || || || || || || || || || ||
active shielding ||
The more expensive type of shielding that uses additional solenoid magnets outside the
|| || || || || || || || || || || || ||
cyrogen bath that restricts the magnetic field line to an acceptable location is the: - correct
|| || || || || || || || || || || || || || || ||
answer✔✔Active- passive shielding can be accomplished by lining the walls with steel || || || || || || || || || || || ||
while the more expensive alternative is active shielding
|| || || || || || ||
,Surface coils are connected inside the scanner by cables. These cables shouldnt touch the
|| || || || || || || || || || || || || ||
patient because: - correct answer✔✔They could burn the patient.
|| || || || || || || ||
Quadrature design coils give you a lower SNR. true or false? - correct answer✔✔True:
|| || || || || || || || || || || || || ||
Quadrature coil designs improve SNR due to increased coverage. || || || || || || || ||
The two coils in a magnet used to transmit RF are the shim and tune coils. true or false? -
|| || || || || || || || || || || || || || || || || || || ||
correct answer✔✔False: transmit coils are usually the body and head coils.
|| || || || || || || || || ||
Magnetic field gradients are generated by what? - correct answer✔✔coils of wire situated
|| || || || || || || || || || || || ||
within the bore of the magnet.
|| || || || ||
In the event of a cryogenic leak or catastrophic magnet quench, the first thing the
|| || || || || || || || || || || || || || ||
technologist should do is? - correct answer✔✔evacuate all persons from the scan room.
|| || || || || || || || || || || ||
The given field strength (ex..1.5T) of the magnet is maintained at the: - correct
|| || || || || || || || || || || || || ||
answer✔✔Middle od the axis of the bore, middle of the axis reamins at the field strength. || || || || || || || || || || || || || || ||
When employing a surface coil the signal intensity: - correct answer✔✔decreases as
|| || || || || || || || || || || ||
anatomy gets further from the coil. || || || || ||
Surface coils are "receive only" coils. true or false? - correct answer✔✔False
|| || || || || || || || || || ||
The largest possible receiver coil should be chosen: true or false? - correct answer✔✔False-
|| || || || || || || || || || || || || ||
optimally smallest coils are best || || || ||
, Surface coils are free standing & have no electrical components. true or false? - correct
|| || || || || || || || || || || || || || ||
answer✔✔false
The precessonial frequency of hydrogen at 1.5T is 68MHz. true or false? - correct
|| || || || || || || || || || || || || ||
answer✔✔False- Hydrogen @1.5T is 63.86MHz || || || ||
What happens to the precessional frequency of those protons which experience a higher
|| || || || || || || || || || || || ||
magnetic field? - correct answer✔✔It increases
|| || || || ||
To achieve the shortest scan time possible, which of the following would not be selected. -
|| || || || || || || || || || || || || || || ||
correct answer✔✔Shortest TE possible. TE doesnt effect scan time
|| || || || || || || ||
In a 2DFT scan using a TR of 1 second, a TE of 30msec, a FOV 24, Matrix 128 & 2 NSA.
|| || || || || || || || || || || || || || || || || || || || || ||
What is your total scan time for 1 slice? - correct answer✔✔4.2 minutes; 1x128x2/60=4.2
|| || || || || || || || || || || || ||
In MR , the frequency of water is_________ as compared to the frequency of fat. - correct
|| || || || || || || || || || || || || || || || ||
answer✔✔Higher- The frequency in H2O is higher than fat || || || || || || || ||
The following statement: Any signal must be sampled at least twice per cycle in order to
|| || || || || || || || || || || || || || || ||
represent or reproduce it accurately; is a mathematical principle called: - correct
|| || || || || || || || || || || ||
answer✔✔Nyquist Theorem ||
If the Nyquist theorem is not adhered to in the MR experiment what is the result? - correct
|| || || || || || || || || || || || || || || || || ||
answer✔✔Aliasing
At equilibrium more nuclear spines are________ with the magnetic field. - correct
|| || || || || || || || || || || ||
answer✔✔In Alignment ||
