0:01

So our next topic is enhancing MRI findings.

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These are the things that we look at on MRI that

0:09

enhance with contrast and how we describe them.

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So the three major areas are a focus,

0:17

a mass, or non-mass enhancement.

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And then, of course, lymph nodes.

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We're always looking at lymph nodes

0:23

in the breast, in the axilla, and

0:26

in the internal mammary space.

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Focus is an enhancing dot less

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than five millimeters in size.

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The shape and margin cannot be seen clearly.

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It's not clearly space-occupying, and

0:39

it can't be further characterized.

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It also should be unique compared to background

0:44

parenchymal enhancement, and typically scattered

0:47

foci of enhancement represent background.

0:54

This is an example of a focus indicated by the

0:56

yellow arrow, so just this little dot here.

0:59

The other dots in the image are actually

1:01

parts of blood vessels, so as you scroll

1:03

through you can see the difference.

1:06

This is another focus, a little bit larger.

1:10

And you can see that this is really

1:12

unique compared to the background.

1:14

There's nothing else that looks like that.

1:17

So benign features would include

1:20

foci that are not unique.

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So background parenchymal enhancement foci.

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Ones that are high signal on bright fluid

1:27

imaging, which is, you know, T2 or STR.

1:31

Fatty hilum, which would indicate

1:33

a possible small lymph node.

1:35

persistent kinetics, and stable

1:37

or seen on a baseline study.

1:42

Suspicious features would be those that

1:44

are unique from the background, not

1:47

bright on T2-weighted imaging, no fatty

1:50

hilum, washout kinetics, and increased

1:54

or new compared to the prior study.

1:57

And this algorithm is from a training

2:02

session for an abbreviated MRI study

2:05

that was done by Chris Comstock and

2:10

Christiana Kuhl and a group of researchers.

2:13

These algorithms that I'm going to show

2:15

apply to an approach to interpretation

2:20

of a baseline abbreviated MRI, and we've

2:23

kind of extrapolated them a little bit

2:25

to use them for a full protocol MRI

2:28

as well, but just keep that in mind.

2:31

So for a unique three to five

2:33

millimeter focus on the baseline exam,

2:37

if it's just an inflammatory cyst,

2:39

we're going to consider that benign.

2:41

If the focus has circumscribed

2:43

margins and is high T2 signal, we're

2:45

going to consider that one benign.

2:47

If it doesn't have high T2 signal,

2:50

then we have to look at, you know,

2:51

does it have rim enhancement or not?

2:54

If it does, we'll biopsy it.

2:55

If it doesn't, we're going

2:56

to follow it in six months.

2:58

And then, of course, if a focus has irregular

3:00

shape or margins, we should biopsy it.