MRI

Question 1

What is MRI ?

Answer 1

A diagnostic imaging modality using magnetic resonance technology

Question 2

Was renamed MRI due to the word “nuclear” in what year ?

Answer 2

1980 s

Question 3

The 1st MRI units were sold commercially ?

Answer 3

1984

Question 4

How does MRI work ?

Answer 4

By Magnet , Nuclei (Protons) and Radio Frequency

Question 5

Magnet ?

Answer 5

The earth’s magnetic field is about 0.5 gauss

MRI : 0.5 tesla , 1 tesla , 1.5 tesla and 3 tesla

Question 6

MRI measurements ?

Answer 6

Gauss: unit used in the measurement of a low magnetic field strength

Tesla (T) : unit used in the measurement of a high magnetic field strength

Question 7

Radio frequency ( RF) :

Answer 7

It is a radio waves and use to excite the protons

Question 8

RF coils ?

Answer 8

Coils send and receive RF signals,
come in various shapes and sizes
and work best when placed close to the scanned body part

Question 9

Magnetic strength ?

Answer 9

Earth’s magnetic field = 0.5 Gauss

Which 1.5 Tesla magnet is 15,000 Gauss about 30,000 times stronger than Earth’s 0.5 Gauss of magnetic field

Question 10

what are screening form ?

Answer 10

Pacemaker
Cerebral Aneurysm clips
Implanted electromagnetic devices
Cochlear implants
Metal fragment in body
Pregnancy

Question 11

Pregnant patient in MRI ?

Answer 11

Not known biological effects on fetus
Not recommended 1st trimester

Question 12

Pregnant employee ?

Answer 12

Technologist should set up the patient, but not to remain in the room during image acquisition

Question 13

Advantages of MRI ?

Answer 13

Non Ionizing Radiation
Minimal Preparation Time
Multi Plane Imaging
Soft Tissue Detail

Question 14

What are multi plane imaging ?

Answer 14

Axial , Coronal , Sagittal , Oblique and
3D Reconstruction

Question 15

Soft tissue detail ?

Answer 15

MRI is capable of imaging muscles, tendons, ligaments and tumors

Question 16

MR angiography ?

Answer 16

Method of visualizing vessels
Non-invasive procedure
No contrast media

Question 17

Disadvantages of MRI ?

Answer 17

High cost , patient Size , patient screening ,
Claustrophobia
Sensitive To Motion and Slower Modality

Question 18

Patient can have an mrI when ?

Answer 18

Patient with Pacemaker, aneurysm clips, cochlear implant and Trauma

Patient cooperation can have MRI

Question 19

Slower modality ?

Answer 19

Takes a longer time to perform compared to CT exams
Average 20-45 minutes

Question 20

Patient size ?

Answer 20

Table weight limit is 300 pounds , 130
Some patient are unable to fit in the scanner due to their size ( open MRI is an option)

Question 21

Claustrophobia

Answer 21

As many as 20% of patients cannot complete the scan due to claustrophobia

Question 22

what modality sensitive to motion ?

Answer 22

MRI

Question 23

Sensitive to motion ?

Answer 23

Due to the length of the exam, it may be difficult for patients to hold still
Pain , Discomfort and Uncooperative

Question 24

Patient monitoring equipment ?

Answer 24

Only MRI compatible equipment are allowed in the scan room

There is MRI compatible equipment for Anesthesia cases