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MRI safety and protection.

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The important thing that we need to consider and when we think of MRI as

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the safe modality is really if we're going to compare this against

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ionizing radiation.

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Let's just do a quick recap of safety of

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ionizing radiation. I'm a big fan of this infographic.

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This is from X K C D. Um,

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this is essentially a summary of different levels of radiation exposure.

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This just describes the average chest ct,

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uh, seven milli sieverts.

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What would represent an egregious over-exposure

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for a a CT patient?

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There was a Mad River incident in Northern California a number of years ago

0:54

where a six year old boy got exposed to

0:59

dozens of head CT studies when the technologist kept

1:03

hitting start study, start study,

1:06

start study for a child who was having a hard time holding still.

1:11

That's probably one of the most egregious over exposures that

1:16

we've heard of in the states in quite some time now,

1:19

that boy probably will have damage to his lenses

1:24

and probably has a low single digit lifetime

1:29

risk of developing long-term cancers.

1:33

If we take all of the previously accumulated doses in

1:38

that XKCD infographic and we combine them together,

1:43

and this includes one hour on the grounds near Chernobyl and

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chest x-ray and a CT study,

1:52

all of those combined produce 75 millisieverts plus or minus.

1:58

In the United States,

2:00

at least radiation workers are limited to 50

2:04

millisieverts of occupational exposure per year.

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This is approximately half of the exposure

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that we can actually correlate a lifetime risk of

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cancer development.

2:20

Somewhere around a hundred milli sieverts represents the lowest

2:25

measurable lifetime increase in risk in development of cancers.

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So if we have a patient who has 20%

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greater exposure from a fluoro study, what does that mean to them?

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In terms of lifetime risk?

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It probably is so small that we can't actually measure it.

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So consider all of the structures that are in place

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for the protection of patients, protection of workers

2:58

In the radiology environment. Protection from ionizing radiation sources,

3:03

right? You're required to have radioactive materials licenses from the nrc.

3:08

You're required to have radiation safety officers.

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You're required to have a radiation safety committee with minimum participation

3:17

and minimum quarterly meetings. Now,

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contrast that with what can happen in mri.

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If we look at this risk table now,

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the risk on the vertical axis is the likelihood

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that the adverse event, the consequence will occur.

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And on the horizontal axis is the magnitude

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of the relative consequence.

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If we're talking about X-ray ct,

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we're talking about certain exposures,

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but we're talking about insignificant consequences for

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any individual adverse event or exposure.

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If we're talking about mri, by contrast,

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we can have do still

4:16

injure and kill people, injure people, very gravely.

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We can produce major and critical results,

4:25

impacts from MRI safety, from adverse events. Now,

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those are extraordinarily rare.

4:32

So the worst possible MRI adverse events probably

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live in the lower right hand quadrant of this

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risk matrix, whereas the risk of harm

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related to x-ray CT fluoro

4:55

lives somewhere on the left hand side of this graph.

5:00

So just taking a look at the intersection of

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consequence and likelihood,

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we need to recognize that in many ways,

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mri the quote unquote safe modality

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is a greater risk, a greater potential threat to patients.

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And as a result of litigation risk to the institution,

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risk to the individuals involved, including the radiologist.

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MRI represents a greater potential risk than does

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CT or x-ray or fluoro. Unfortunately,

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MRI safety is not a standard element of radiology

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residency training.

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So if we look in the A C G M E program requirements

5:53

for diagnostic radiology, and we look specifically for

5:56

Mri, we define the specialty.

5:59

We make sure that the faculty have backgrounds in modalities,

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including mri. You don't have to have additional faculty.

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Residents need to be able to do interpretation of MRI

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and residents need to have the principles of the physics behind

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mri. And that's it.

6:22

There's nothing in the A C G M E program requirements for

6:27

diagnostic radiology that says that as a part of your

6:31

residency program, you have to have any MRI safety training. Now,

6:36

obviously, many graduate programs,

6:40

many residency programs have MRI safety

6:44

as an element of the residency,

6:48

but it's important to recognize that it is not a minimum

6:52

requirement and therefore you or your colleagues may

6:57

have been shortchanged in terms of what was presented to you

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in your training with respect to MRI safety,

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consider for a moment the amount of training that you may have had on

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radiation safety and all ARA principles, um,

7:17

and in your mind contrast that with the training that you received

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on MRI safety. Um,

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it would be my expectation that the MRI safety probably comes

7:30

up significantly short in a comparison between the two.