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Alright, so this is our second case of the day.

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This is a 34-year-old,

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a 30-year-old female. Sorry.

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With painful periods in pain during intercourse and difficulty conceiving.

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So when I approach a female pelvis,

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I always start with the T2 nonfat sat images.

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As I've said, these are our work course images.

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And I start by scrolling through the sagittal just to kind of get a lay of the land,

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particularly thinking about how all those compartments are relative

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to each other and the orientation of the uterus.

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Then I'll take a look,

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a quick look through the axials to get a better look at the adnexa bilaterally.

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So there are a couple abnormal findings that we can point out right off the bat.

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So, the first is that this patient has

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a fairly large cystic lesion in her left adnexa here.

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It's T2 hyperintense, has a T2 hypointense nodule

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down here at the back and a thin septation,

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which we'll have to take a look at again later.

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I'm going to kind of break from my normal search pattern

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and jump into this here so that we can make a couple of teaching

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points before we look at the rest of the case.

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So I'm going to pull up the axial

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T1 fat saturated image and we're going to look at the same structure.

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So here, we can see that it is very, very intrinsically T1 bright.

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This is a pre contrast image,

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so this cannot be accounted for by gadolinium.

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This is intrinsic T1 hyperintensity.

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It is more T1 hyperintense than it is T2 hyperintense.

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And if I can convince you, this T2 dark nodule back here

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corresponds to this little focus right here that is just a little bit

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T1 brighter than the rest of the T1 brightness.

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So this is a very classic appearance of an endometrioma,

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which is the most common manifestation of endometriosis

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and is defined as a thick walled

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cystic structure containing blood products of varying chronicity.

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These blood products are what account

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for the intrinsic T1 hyperintensity of the lesion.

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They're bilateral in 50% of cases.

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They can sometimes contain these thin septations.

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That's okay.

2:20

They can be unilocular or multilocular

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because there are blood products in them,

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they can restrict defusion a little bit.

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The way that we differentiate

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endometriomas from hemorrhagic cysts are by the relative T2 and T1 signal.

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So hemorrhagic cysts

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will be more T2 hyperintense and less T1 hyperintense than endometrioma.

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Another pearl is that endometriomas tend to be more homogeneous on the

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T1 weighted images and more heterogeneous

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on the T2 weighted images.

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And hemorrhagic cyst will be the opposite.

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So they'll be more homogeneous on the T2 and more heterogeneous on the T1.

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Another way that we can differentiate is to get a follow up ultrasound.

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Hemorrhagic cyst will evolve

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in appearance or resolve in six weeks,

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whereas endometriomas will remain stable.

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So now that we've talked a little bit

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about endometriomas, can we get the first question up, please?

3:24

Ashley?

3:24

So what is the most specific sign of an endometrioma?

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Is it the T2 Dark Spot sign,

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T2 Shading, T1 Hyperintensity, or Bilaterality?

3:35

All right.

3:36

So people have answered that T1 hyperintensity

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is the most specific sign of an endometrioma.

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So the most specific sign is actually

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the T2 dark spot sign, which is what we see here.

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So the reason that T1 hyperintensity

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isn't specific is that we can also see T1 hyperintensity in hemorrhagic cysts.

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And so while it is sensitive for endometrioma, it's not specific.

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This T1 dark spot sign, which is basically extremely

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inspissated blood product, is 93% specific for an endometrioma.

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It's only 35% sensitive though, it's not often seen.

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But when you do see this dark spot, you're pretty darn sure you're looking

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at an endometrioma and not a hemorrhagic cyst

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or another type of lesion.

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T2 shading is another kind of common buzzword

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that we hear with endometriomas, that is the T2 dark signal.

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There's some misunderstanding out there

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that it needs to be kind of layering T2 hypointensity.

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That's not the case. It just has to be T2 dark,

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that is less specific than the T2 dark spot sign for endometriomas.

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So the second point about endometriosis is to make in this case is

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the presence of superficial endometriotic implants.

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So if you look really carefully on this T1 fat saturated image,

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we have our cervix here, and we can see along the back wall

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of the cervix these very, very subtle linear areas of T1 hyperintensity.

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These are our small superficial endometriotic implants.

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Superficial endometriosis is the second

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morphology of endometriosis after endometrioma.

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They are defined as raised areas of glandular tissue that are

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on the peritoneal surface but that do not invade more than 5 mm.

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So they're not seen very well by MRI because they don't really invade.

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And all we can see are these kind of very

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subtle linear and punctate areas of T1 hyperintensity.

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There won't be a T2 correlate to these findings.

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MR often underestimates the amount of superficial endometriosis in the pelvis.

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MR is much better for deep infiltrating endometriosis,

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which we'll talk a little bit more about soon.

5:46

Yeah. So other findings that we can see

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in this case. So, on the sagittal T2,

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we can see that the uterus is retroflex.

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So uterine version, antiversion versus retroversion

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is defined as the angle of the uterine body,

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including the cervix.

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So the angle of the whole uterus relative to the angle of the vagina.

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Uterine flexion is defined as the angle of the uterine body

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relative to the cervix itself.

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So this uterus is both retroverted and retroflexed.

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And retroversion of the uterus isn't a normal finding.

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It's less common than antiversion, which is the most common lay of the uterus.

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But to see retroflection like this, it makes you think, is there something

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along the uterine serosa back here that is tethering and causing scarring

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down of the uterus and kind of infolding on itself.

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And if we look on the axial,

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we can see this linear area of T2 hypointensity that is kind of bridging

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the rectum to this endometrioma and to the uterus.

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This is a little bit of deep infiltrating endometriosis that's responsible

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for that tethering and for the appearance of the uterus.

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And we'll have a better look at deep

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infiltrating endometriosis on another case.

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As a bonus, this patient also has a septate uterus.

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You can see the uterine septa right here.

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We know that it's septate because this indentation is greater

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than a centimeter in length,

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but the uterine serosal contour at the fundus is maintained.

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She also later had an HSG for evaluation of her infertility.

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Have had the septum partially resected at that time.

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And what we can see is that she has patent tubes,

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but there are all these adhesions around the ovary that is causing the contrast

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that is spilled to be kind of loculated in the pelvis around the ovary as opposed

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to free spillage, which is what we see here on the right.

7:52

Great. Okay. So I think those are all the main

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teaching point I wanted to make with this case.

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I'm going to move on to the third.