Transcript mri safety lesson

Introduction
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This course is designed to inform individuals of
the necessity of Magnetic Resonance Imaging
(MRI) safety.
Any individuals that are in contact with an MRI
environment and have knowledge of MRI
techniques would greatly benefit from this
lesson.
Click the right arrow to advance slides, and the
left arrow to go back to the previous slide
MRI Safety
It could mean the
difference between
life and death!
© Tiffany Heider, 2005
What is MRI?
Magnetic Resonance Imaging (MRI) is becoming very popular within
the world of medical diagnosis and research. MRI is a technique that
uses a magnetic field and pulses of radio wave energy to provide
pictures of organs and structures inside the body. For an MRI
procedure, the area of the body being studied is positioned inside a
strong magnetic field. The MRI can detect changes in the normal
structure and characteristics of organs or other tissues. Due to the
strong magnetic field, there are many safety issues to consider with
this type of testing. Inadequate knowledge can result in serious
injury and possible death.
Who gets MRIs?
Everyday individuals, such as
you, could one day have an
MRI. As well as your family
pet, or a sick zoo animal.
Their safety depends on your
knowledge.
Magnetic Fields
There are 2 Types of magnetic fields

Main magnetic field-responsible for the
alignment of nuclei.
-always on
-the middle of the magnet (inside
the bore)
Types of magnets, cont.
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Fringe or static field- stray magnet field
outside the bore of the magnet
-always on
-No respect for confines of walls
or doors, floor or ceilings
-MRI room is shielded to
confine the fringe field to inside the room
Why do I need to be safe?
Patients lives are in your hands
and they trust that you do not
abuse that. Patient screening,
in-depth knowledge, and proper
precautions are expected of
you.
MRI safety precautions
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Patient and personnel screening is the
most effective way to avoid potential
safety hazards.
Patients or personnel with metallic
implants should be examined.
Screening forms should be filled out by
anyone entering the MRI exam room.
Screening forms should be filled out
completely and correctly. Patients
unable to fill out a screening form must
have a family member fill it out for
them.
Biological Effects
No radiation is used in MRI, MRI is based
on the transmission of radio waves.
 No biological or adverse effects
 No biological or adverse effects to fetus or
pregnant women.
-because of cell division during the first
trimester it is recommended by the FDA
that women do not have an MRI in the first
trimester unless medically necessary.
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Projectiles
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Ferromagnetic metal objects can
become airborne.
- small objects (paper clips,
hairpins) can reach the velocity
40 mph
Surgical tools such as
hemostats,scissors, and clamps.
Even ones made of surgical
stainless steel can be highly
magnetic.
O2 tanks
-All objects tested with handheld bar magnet first.
Projectiles, cont.
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Janitors and cleaning crew must
also be aware of MRI
precautions. Buffers and
cleaning tools can be attracted by
a magnet.
Vendors working on MRI
equipment must also be trained
and have the proper MRI tools
that are nonmagnetic.
It is the departments
responsibility to assure no
unauthorized persons are to
entire a scan room.
Implants/Prostheses
Metallic implants in patients or employees
must be identified before entering room.
 Heating and Torque can occur-can cause
serious effects
 Metal Implants can also cause artifacts on
the films
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Contraindications
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A factor that renders
the administration of
a drug or the carrying
out of a medical
procedure
inadvisable.
Intra Cranial Vascular Clips
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Absolute
contraindications,
under no condition
may that person enter
the MRI room.
Motion of the clip
may damage the
vessel resulting in
hemorrhage or even
death.
Intra Vascular and Extra Cranial
Coils, Filters, Stents
Intra Vascular coils, filters, and stints
- 8 weeks post surgical, check with the
technologist prior to the exam.
 Extra Cranial vascular clips
-4-6 weeks after implantation-also check
with technologist prior to exam
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Vascular Access Ports and
Heart valve implants
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Vascular access ports are MRI
compatible
Heart valves are usually
compatible, however the type
and model number is required
to be checked prior to the test.
-Usually safe after 8 weeks
post implantation and scar
tissue has formed around the
implant.
Ontological or Ear and Ocular
or Eye Implants
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Cochlear implants- all
contrainindicated
Ocular implants-some are
ferromagnetic-all patients need
to be screened thoroughly.
Intra ocular foreign body- metal
in the eye.
-all patients who work or grind
metal need to have an x ray
before having an MRI.
-Metal in the eye could could
heat up or move causing
blindness.
Contrainindications for MRI
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Cardiac Pacemakers
Cochlear Implants
Tissue Expanders
Ocular Prosthesis
Neurostimulators
Bone growth stimulators
Defibrillators
Drug Infusion pumps
Intracranial Vascular
Clips-i.e. aneurysm clips
Claustrophobia
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Claustrophobia- the fear
of being in enclosed
spaces.
Many people suffer from
this and some patients
may need to be sedated
before having an MRI.
Proper sedation
monitoring must be used.
SUMMARY
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MRI suites are a valuable but potentially
dangerous medical tool.
MRI magnets are always on.
The smallest metallic object can be attracted into
a MRI magnet.
Patients must be screened prior to examination.
Any individual entering the MRI scan room must
be properly trained on the hazards.
Patient and employee safety must always come
first.
ASSESMENT
Next you will be asked a series of
questions testing your knowledge on the
given material.
 You will be given a question/scenario and
a choice of answers. Choose the best
answer and click to the next slide to see an
explanation of answers.
 This is for your benefit so please so
looking ahead at the answers.

Question 1
Who are MRIs designed for?
1.
2.
3.
4.
5.
Very sick individuals
Individuals with trauma or physical injury
Individuals with experimental consent
Animals
All of the Above
Question 1 Answers
The correct answer is #5 All of the above.
MRIs do not treat just deathly ill
individuals, or individuals with recent
trauma. An MRI can diagnosis all kinds of
diseases or injuries in all people as well as
animals.
Question 2
Sally is an MRI technician. They are not in
the middle of a scan and she wants to get
the scan room organized. Since there are
no scans going on it is okay for Sally to
take her cell phone into the room with
her.
1.
2.
True
False
Question 2 Answer
The correct answer is #2 False. MRI
magnetic fields are always active
regardless if there is a scan going on. As
long as the machine has power the
magnetic field is present in the room.
Question 3
Mark is an MRI supervisor. His department
has gotten backed up with patients and
they are running behind. He knows the
next patient has an accurate health
history and tells his technician to skip the
screening form. Is Mark’s decision the
correct one?
1. Yes, he is the supervisor.
2. No, the form should be filled out.
Question 3 Answer
The correct answer is #2 No. Even though
the patient has a complete health record
and Mark is the supervisor, safety should
never be disregarded. The patient could
have implants or other metallic objects that
could be attracted to the magnet. These
objects could result in patient injury or
death. The screening form must be
complete.
Question 4
Which of the following are NOT a MRI
safety hazard.
1. Medical scissors
2. Patient oxygen tank
3. Radiation
4. Hair pins
5. Metal implants
Question 4 Answer
The correct answer is #3 Radiation. A MRI
suite does not use radiation as in CT suites.
A MRI machine uses magnetic fields and
radio waves rather than radiation waves.
However any material made of metal that
is not non-magnetic may be attracted into
the magnet.
Question 5
A patient states that they have a metallic implant.
However, they also inform you that they have
had an MRI before, and it will not attract to the
magnet. If the patient says it will not attract,
then you should:
1.
Continue with the exam.
2.
Advise that the exam cannot be completed.
3.
Have the patient sign a waiver.
Question 5 Answer
The correct answer is #2 Advise that the
exam cannot be done. If you were to scan
that patient and something were to happen,
then you would be responsible. It is better
to notify your superiors and the patient
rather than be liable for an injury or death
that could result in a lawsuit and personal
emotional stress.
Question 6
A vendor comes in to work on your MRI injector.
You are headed out to lunch, but want the work
to get done. What do you do to accommodate
both of you?
1.
Give him the keys to the room and go to lunch
2.
Tell him to come back
3.
Ask him if he is MRI safe before allowing him
into the room while you are gone
4.
Ask him to pull the unit out of the room before
you go to lunch and work on it outside the
room.
Question 6 Answer
The correct answer is #4. Ask the vendor if
he can work on the unit outside of the MRI
scan room. This allows you to observe the
individual while in the room, lock the
room once he is done, and be sure that no
magnetic tools enter the room. If he is
unable to pull the unit out ask him to come
back or have a collegue supervisor the
MRI room.
Question 7
True or False
A patient informs you that he/she gets
nervous in tight spaces. Since this is the
case, you cannot perform an MRI on this
individual.
Question 7 Answer
The correct answer is false. Many
individuals have Claustrophobia. The MRI
bore is a very tight fit, but a patient can be
sedated. However, there must be a nurse
there to perform the sedation and a
qualified individual to monitor MRI
compatible monitoring equipment.
CONGRATULATIONS
YOU HAVE COMPLETED THE MRI
SAFETY ASSESMENT. I HOPE YOU
HAVE RECEIVED A LOT OF
VALUABLE INFORMATION AND USE
IT IN YOUR DAY TO DAY CAREER.
Reference
Westbrook, C. Kaut, C.(1998). MRI in
Practice. MRI Safety, chp 10. Blackwell
Science.ltd.
The American Heritage Dictionary of the
English Language, Forth
edition.(2000).Houghton Mifflin Company