0:01

So our next topic is interpretation

0:03

and reporting, and interpretation

0:05

is, is very important.

0:07

It's sometimes hard to put this into, um,

0:11

just a series of steps, but here we go.

0:14

We'll review the history and prior reports.

0:17

We want to review all the relevant

0:19

imaging that includes current and prior

0:22

mammograms, breast ultrasounds, prior

0:24

MRI, whatever the patient has had done.

0:27

We want to understand the

0:29

indication for the exam.

0:30

Is this high-risk screening?

0:32

Are we following up something?

0:34

Does the patient have a new cancer?

0:35

We want to know, you know, why they're here.

0:39

And I think the first step is

0:40

just to assess image quality.

0:42

You know, is this an adequate exam?

0:46

Sometimes we might notice that the patient

0:48

didn't get the contrast, or power injector broke,

0:51

or, you know, something happened. Often the

0:54

technologist will make some sort of a note and

0:57

we have to decide whether we can interpret these

1:00

images or does the exam need to be repeated?

1:02

And the same goes for motion.

1:04

If the patient does a lot of moving

1:06

between the pre and post contrast

1:09

exam, or they're moving continuously

1:11

during the exam, it may make the exam

1:15

quality inadequate for interpretation.

1:17

So that's important to note.

1:20

I recommend a quick review of the MIP and

1:23

the first subtraction series just to get

1:25

an overview of, you know, what's going on.

1:29

And then evaluate the reason for the exam

1:31

or whatever area we're trying to follow up

1:34

and then I kind of go back and review each

1:36

sequence carefully and just to review,

1:39

you know, what we're looking for on each sequence.

1:42

And the localizer, that's that couple of

1:45

images in three planes, we just do a quick

1:49

review of that for incidental findings.

1:51

And I've been surprised by what

1:52

I've found outside of the breast.

1:54

And sometimes it's only visible

1:56

on these localizer images.

1:57

So just take a, you know,

1:59

10 seconds to review that.

2:01

The MIP is going to give us an overview and an

2:04

idea of the background parenchymal enhancement.

2:07

The first subtraction series will look

2:11

at background parenchymal enhancement

2:12

and review for enhancing findings.

2:15

The T1 non-fat-saturated images, that's good

2:19

for the amount of fibroglandular tissue.

2:22

And looking for artifacts from

2:24

post-surgical change and biopsy

2:26

clips that can be very helpful.

2:28

And this is also a good sequence

2:30

to look for fat signal intensity

2:34

internal to a lesion and lymph nodes.

2:38

The next sequence is the STIR

2:40

sequence where fluid is bright.

2:43

So we're going to look for cysts, fluid

2:45

collections, edema, and correlations with

2:48

enhancing findings because, you know, as

2:50

we saw from our interpretation algorithms,

2:52

some of those algorithms change depending

2:55

on whether the finding is T2 bright or not.

2:59

And the T1 fat-saturated pre-contrast

3:02

images, we're going to look at

3:03

proteinaceous fluid in the ducts or cysts.

3:07

And then in the post-contrast series, we're

3:09

looking at that background enhancement.

3:11

And a careful review for enhancing findings, and

3:14

we can compare that to the pre-contrast images.

3:17

Often, we'll put up the pre and post-contrast T1

3:23

weighted images and just sort of scroll through

3:25

them together and just make sure that whatever

3:28

is enhancing wasn't bright before contrast,

3:31

and we'll just compare them back and forth.

3:34

Sometimes when there's a little bit of motion,

3:38

and the subtraction images can be very limited

3:41

when there's a patient motion, but those

3:43

source images, the T1 FATSAT pre-contrast

3:47

and post-contrast images can be used even if

3:50

you have motion between the pre and the post.

3:52

So things to think about.

3:54

So we want to assess any enhancing lesions and

3:58

during our review, our series should be linked.

4:01

That helps us to know that we're

4:02

looking at the same lesion.

4:04

We'll review the subs and the

4:06

pre- and post-contrast T1 images.

4:08

As I said, check the STIRs

4:10

for T2 hyperintense signal.

4:12

And the T1s for fat signal intrinsic to the

4:16

lesion. We'll always compare to prior exams.

4:19

Sometimes we can find that a lesion that

4:23

might look a little bit funny on our current

4:25

study might be something we'd like to biopsy.

4:27

If we find that it's stable for several

4:29

years, that may not be necessary.

4:32

We always evaluate our kinetics, our

4:35

color map, and the time-intensity curves

4:37

that we just discussed previously.

4:40

And then we'll review the

4:41

structures outside the breast.

4:43

And we have had situations where MRI of

4:48

the breast was the means of discovery of

4:52

unknown lung cancer, unknown pneumonia,

4:58

thyroid nodules, thyroid cancers,

5:02

mediastinal problems, aortic problems.

5:06

You just want to be aware

5:07

that it's not just the breast.

5:10

We have to be responsible for

5:12

whatever anatomy is on the images.

5:17

So once we have an enhancing finding,

5:18

we have to decide how we're going to

5:20

describe that finding using the BI

5:22

RADS lexicon that we just described.

5:26

And those BI RADS descriptors,

5:29

unfortunately don't lead to a numerical

5:31

score or an interpretation guideline.

5:34

This is the piece that I feel is maybe

5:39

a little bit deficient in BI RADS, you

5:42

know, when you look at some of those other

5:44

classification systems that are more recent,

5:46

like TI RADS. The descriptors of a lesion

5:52

actually go along with a numerical score.

5:55

So you add up that score and it tells

5:58

you whether you need to biopsy or

5:59

follow or what your plan is going to be.

6:02

In BI RADS, those descriptors don't

6:04

really have a numerical score.

6:06

So it's a more subjective interpretation

6:09

that brings you from the descriptive

6:12

lexicon to that BI RADS assessment category.

6:16

And, you know, finally, we're going

6:17

to decide on our BI-RADS assessment

6:19

category and our management.

6:21

And, you know, if we're going to biopsy,

6:22

we have to decide how to biopsy and

6:25

all those things we just discussed.