MRI Basics

Question 1

The liquid helium used in MRI is a type of:

Answer 1

CryoGEN

Question 2

Superconductive magnets use a ______ to hold liquid helium.

Answer 2

CryoSTAT

Question 3

MRI- related accidents are:

Answer 3

rarely reported

Question 4

Of the 3 magnet types used in MRI, which can be routinely turned on and off?

Answer 4

Resistive

Question 5

What is the summation of all the magnetic moments of individual spins along the same plane as the magnetic field is referred to as?

Answer 5

Longitudinal Magnetization Vector

Question 6

Zone III is which area?

Answer 6

Patient Holding area

Question 7

True/False

Hearing aids are okay to be worn in the magnet room.

Answer 7

False

Question 8

True/False

A cardiac pacemaker is always a contraindication of having an MRI scan.

Answer 8

False

Question 9

At minimum, a patient should be screened at least ___ times before entering the magnetic room. The 1st screening is done by _________.

Answer 9

3 times.

1st screening done by referring physician.

Question 10

Anyone entering the magnet room must be screened by:

Answer 10

a qualified MRI Professional.

Question 11

In case of sudden release of gaseous helium into the amgnet room, what is the FIRST action the technologist should take?

Answer 11

Remove the patient from the bore & magnet room.

Question 12

A release of helium into the magnet room can lead to death caused by what?

Answer 12

asphyxiation

Question 13

A quench is always:

Answer 13

Uncontrolled or controlled

Question 14

An explosive conversion of liquid helium to gaseous helium is called a:

Answer 14

Quench

Question 15

Helium liquifies at -453° or _______

Answer 15

4° K

Question 16

As the distance of an object to the magnet decreases, the force exerted on the object _______

Answer 16

increases

Question 17

the amount of force a magnet exerts on an object depends on the:

Answer 17

amount of ferrous material on the object and the distance to the center of the magnet.

Question 18

When used properly, MRI has NO:

Answer 18

adverse biological effects

Question 19

10,000 Guass is equivalent to:

Answer 19

1.0 Tesla

Question 20

In the absence of a magnetic field, the orientation or “spins” of hydrogen protons are all:

Answer 20

random

Question 21

Of the 3 magnet types used in MRI, which is the one used the most?

Answer 21

Superconductive

Question 22

True/False:

The magnetic field strength of an MRI system can be determined by looking at its size

Answer 22

False

Question 23

As magnetic field strength increases, the number of protons that align in the parallel direction of the magnetic field vs. the anti-parallel direction:

Answer 23

Increases.