0:01

So our next type of enhancement is called

0:03

non mass enhancement, and the abbreviation is NME.

0:08

And this is neither a focus nor a mass.

0:11

And we want to describe the distribution

0:14

of the NME as focal, linear, segmental, regional, multiple regions or diffuse.

0:23

And focal NME is a confined area less than a quadrant within a single duct system.

0:29

Linear would be in a line corresponding to a single duct.

0:34

Segmental is triangular or cone shaped with the apex toward the nipple.

0:40

Regional would define broader than a single duct and it may be geographic

0:46

lacking convex contours and covers at least a quadrant.

0:50

Multiple regions would be at least two

0:53

broad areas separated by normal tissue or fat.

0:56

And diffuse would be widely scattered,

0:59

evenly distributed, similar appearing enhancement throughout the entire breast.

1:05

Some examples of this.

1:07

This would be a focal area of NME.

1:10

So focal NME. Another focal NME. Linear.

1:22

You can see that it's sort of forming a line.

1:27

And a larger example of linear NME.

1:29

This kind of goes from the front to the back of the breast.

1:35

This is an example of segmental NME. Kind of involving this whole area.

1:43

Another segmental NME, involvingthe lateral aspect of the breast.

1:48

A little bit of an apex toward the nipple.

1:53

Here's an example of regional NME.

1:55

It kind of crosses the midline.

1:57

It's more geographic, lacks the convex contour, so it's not really a mass.

2:05

And here's an example of multiple regions of NME.

2:08

And this was felt to represent background.

2:11

Areas in the posterior right breast, posterior left breast,

2:17

a little bit different shapes on both sides.

2:20

So that's multiple regions.

2:22

And then diffuse NME, really involving the entire right breast.

2:29

And then we can talk about our internal enhancement pattern,

2:33

which can be homogeneous, heterogeneous, clumped or clustered ring.

2:40

And homogeneous internal enhancement is

2:45

a uniform signal intensity throughout the area of non mass enhancement.

2:52

Heterogeneous would be mixed signal,

2:56

some high signal, some low signal within that tissue.

3:03

Clumped NME is almost like a group of foci put together. Basically, round or irregular

3:12

areas of enhancement that are in an area that's unique from the rest of the tissue.

3:17

So that's clumped NME.

3:19

Another example of clumped NME.

3:22

The clumps are a little bit larger in this case.

3:27

And another example, this is segmental

3:31

non mass enhancement, but it also has kind of a clumped pattern as well.

3:37

And clustered ring NME is a little bit harder to show.

3:42

But I've indicated an area of clustered ring between the two yellow arrows.

3:48

And you can see that there's rings

3:51

of enhancement surrounding areas of low signal intensity.

3:55

So there's two right next to each other here.

3:57

There's another one here,

3:59

another one here, another one here, and we'll show some more examples of this.

4:05

Suspicious features for non mass

4:07

enhancement include a linear or segmental distribution, because that suggests

4:12

a ductile system, and heterogeneous clumped or clustered ring enhancement.

4:17

Here's our algorithm from the abbreviated MRI reader training material.

4:23

And this is specifically for unique non

4:26

mass enhancement on a baseline high risk screening MRI.

4:29

But again, we're kind of borrowing this approach to all of our MRIs.

4:35

So if the distribution is linear or

4:37

segmental, we're going to recommend a biopsy.

4:40

If the distribution is one of the other descriptors,

4:43

focal, regional, multiple regions or diffuse,

4:47

then we're going to look at internal enhancement.

4:50

And if it's clumped, heterogeneous, or clustered ring, we'll recommend a biopsy.

4:55

If the enhancement is homogeneous

4:57

and there's T2 hyperintense signal, we're going to assume that that is

5:03

related to fibrocystic change, and we consider that to be benign.

5:07

But if there is no hyperintense signal

5:10

or fibrocystic change visible on T2, then we'll follow this over time.

5:16

So, basic algorithm.