0:00

So this case I put in here

0:02

because it's a nice example of deep infiltrating endometriosis.

0:09

So again, I start with the T2 non fat sat images.

0:13

I scroll through on the sagittal.

0:16

I don't see much going on in the anterior compartment.

0:19

In the middle compartment,

0:20

there are a couple of things going on in the myometrium that we can talk about.

0:25

The uterus is anteverted and not terribly flexed one way or another.

0:30

And then in the posterior compartment, there's something going on right here

0:33

in the sigmoid colon that we're going to need to account for later.

0:40

Looking at the axials to take a peek at the adnexa.

0:45

We have one adnexa over here, another over here.

0:51

Nothing super crazy there.

0:53

Then I'll pull my T2 fat sat.

0:56

Oh, sorry. My T1...

1:01

My T1 pres alongside.

1:04

I'm going to look at those together and make sure that I'm not seeing any

1:07

T1 brightness in the ovary that would suggest an endometrioma.

1:11

I'm not seeing any superficial endometriotic implants.

1:17

This protocol happened to have been done without fat saturation.

1:21

And then here with fat saturation.

1:28

So there are a couple of little punctate

1:29

areas of T1 hyperintensity that we see better with the fat saturation.

1:34

That's why our protocol calls for that

1:36

fat saturation on the T1s.

1:40

And then on the sagittal,

1:45

that area of concern involving the sigmoid colon

1:49

we can see is T1 dark as well as T2 dark.

1:56

All right, so now let's kind of talk about what each of these things are.

2:03

And before we do, can we get the next question, please?

2:08

So which portion of the bowel is most commonly involved with endometriosis?

2:12

The terminal ileum, cecum, sigmoid colon, or rectum?

2:18

All right, so people have answered the sigmoid colon.

2:21

The answer is actually the rectum.

2:23

So the rectosigmoid colon, together, account for like 90% of cases

2:28

of bowel involvement.

2:30

But the rectum out edges the sigmoid colon a little bit.

2:34

This case, there is involvement

2:36

of the upper portion of the rectum and then into the sigmoid.

2:40

So I fooled you with this case.

2:41

I'm sorry.

2:43

Bowel involvement in general seen in about 37% of cases of endometriosis.

2:49

So, here we have tethering of the uterus to the rectosigmoid colon here.

2:59

We have obliteration of the rectocervical space

3:04

and the lower part of the rectouterine space

3:06

by this deep infiltrating endometriotic implant.

3:10

There are two morphologies of deep infiltrating endometriosis, which,

3:15

by definition, invades the peritoneal surface by greater than 5mm.

3:19

So there's the chronic stromal fibrotic

3:21

morphology and an active glandular morphology.

3:23

This is a beautiful example of the chronic stromal fibrotic morphology.

3:27

So that morphology is T2 dark and T1 dark.

3:32

It can be nodular or stellate in appearance.

3:37

It causes scarring and obliteration of spaces, meaning that,

3:41

you know, the normal...

3:42

the normal fat plane between the structures and the peritoneal cavity

3:46

is obliterated by scarring that crosses it.

3:50

This is the type of endometriosis that MRI is really great at detecting

3:54

and that the surgeons really want us to tell them about before they go

3:58

into the operating room, because when there is scarring

4:02

and obliteration of spaces, they can't get to those areas

4:05

laparoscopically, and it very significantly impacts

4:08

the surgery that they need to do to help debulk the patient.

4:14

This particular case is a nice example of what's called the mushroom cap sign.

4:19

So that is a descriptor that we use to

4:24

describe bowel involvement with endometriosis.

4:27

You can almost imagine that this is

4:28

a mushroom cap here if we had a little mushroom stalk coming down the bottom.

4:32

And what that is, is it's basically deep endometrio...

4:35

Deep infiltrating endometriosis that invades the muscularis propria

4:39

and results in muscular hypertrophy of the wall of the bowel.

4:42

And that's what is responsible for that mushroom cap appearance.

4:49

When we are describing bowel involvement with endometriosis, it's really important

4:53

that we describe the location of the bowel that's involved.

4:57

Here we can see that area of involvement

4:59

in the axial plane and appreciate just how long it is and how much bowel is involved.

5:04

So we need to describe the location,

5:07

the relationship to the peritoneal reflection.

5:10

This one crosses the peritoneal reflection,

5:13

the distance from the anal verge and the length and number of segments involved.

5:20

And then finally, whether it is greater than 50%

5:23

circumferential involvement or less than.

5:25

And this would be an example of less than.

5:27

And the reason the circumference involvement is important is because it,

5:31

it dictates what type of surgery needs to be done to resect this lesion.

5:34

So if it's less than 50% circumferential involvement,

5:38

the surgeons can just remove that part as it discoid resection.

5:44

If, however, it's greater than 50% of the circumference of the bowel,

5:47

or if there is narrowing, they have to do a segmental resection

5:51

and anastomose the two disconnected segments back together.

5:55

So if there's a lot of bowel involvement,

5:57

the gynecologist may opt to have colorectal surgery involved.

6:00

So it's important to describe all of these features when you see them in the report.

6:08

This patient also, if we focus on the uterus,

6:11

the junctional zone of the uterus here,

6:13

so the T2 kind of gray portion

6:16

of the myometrium that's just below the endometrium is thickened.

6:20

If I were to measure it for you here, it's 13, almost 14 mm.

6:27

So there's junctional zone thickening, which is consistent with adenomyosis,

6:32

which is basically the presence of endometrial tissue in the myometrium

6:39

and is also commonly seen in conjunction with endometriosis outside the uterus,

6:43

since it essentially is endometriosis of the uterus itself.