0:01

So the next special population to consider in

0:04

acute appendicitis is the pregnant population.

0:06

This is another population where you

0:08

want to avoid CT scan, if at all

0:09

possible, to avoid radiation to the fetus.

0:12

One thing to keep in mind as well is that MRI

0:15

dye, while it's not completely contraindicated,

0:20

is contraindicated in pregnant patients, according

0:22

to the ACR contrast manual last updated in

0:25

2020. They do recommend avoiding contrast in

0:28

pregnant women for MRI unless truly necessary.

0:32

And just like our pediatric population,

0:34

it's arguable that you don't actually need

0:35

contrast to evaluate for acute appendicitis.

0:40

Other things to think about in the

0:41

pregnant population are that there are

0:42

multiple different etiologies for why

0:45

they could have right lower quadrant pain.

0:47

Labs in this patient

0:48

population can be deceiving.

0:49

They can have a baseline higher white blood cell

0:51

count and a higher heart rate, so it's difficult

0:53

to know whether there really is an infection or

0:56

whether their pain is from the pregnancy itself.

0:58

Ovarian torsion, or something

1:00

like a renal stone.

1:02

So MRI can answer a lot of those questions.

1:04

So at our institution, we use the

1:06

exact same protocol, pretty much.

1:08

We use T2-weighted images, axial

1:10

coronal, fat-set, and non-fat-set.

1:12

This one's a T2 without fat saturation.

1:15

You can follow the colon, and you see

1:17

this structure coming out right here.

1:18

So the question here already is,

1:19

is this the appendix, or is this

1:21

going to be the terminal ileum?

1:23

Don't really see a fatty valve.

1:24

Maybe there is one right here.

1:26

But not a hundred percent sure.

1:27

So we follow this down a little bit further,

1:31

and you can see this small tubular

1:33

structure right here, extending

1:36

retrocecal into fat right there.

1:37

So now I think we found the appendix.

1:39

We also see a completely

1:40

normal ovary right here.

1:41

Tiny peripheral follicles, normal-sized, and

1:44

then you, of course, have the gravid uterus down

1:47

here, posterior placenta, symmetric ovary

1:50

over here on the left side, which also helps

1:51

confirm that the right ovary is not the problem.

1:55

So you can switch here to a fat-

1:57

saturated image, which we have here.

1:59

Sometimes you can get poor fat saturation

2:01

in a pregnant person; they're larger,

2:02

it can be a little bit difficult to do.

2:04

But, as you're looking through here, this

2:06

is very clearly infiltrating free fluid and

2:10

inflammation in the right lower quadrant.

2:11

There is definitely an acute itis

2:13

going on in the right lower quadrant.

2:15

We identified that appendix on the other imaging

2:18

there, on the T2 axial, and it's thickened.

2:23

More than it should be.

2:24

So this is diagnostic of an acute appendicitis.

2:27

One caveat, which I found in looking

2:29

at a lot of these, is the appendix can

2:31

occasionally look T2 dark if it's not fluid-

2:33

filled, a normal appendix in particular.

2:36

And so do the T2-bright vessels that

2:39

are also in the right lower quadrant.

2:40

So I find, you know, when I'm searching for the

2:42

appendix, you might get fooled several different

2:44

times, but just keep following that structure.

2:46

If it's the appendix,

2:47

it's blind-ending; it will stop.

2:48

If it's a vessel, like in this case,

2:50

you can follow all these T2-dark

2:52

vessels right here; they'll keep

2:53

going up until they meet either with

2:55

an artery or vein somewhere else.

2:57

So that's how you can tell it's a vessel,

2:59

and you have to keep looking for it.

3:02

And terminal ileum right here; appendix

3:04

back here is part of the circular

3:05

structure of the appendix back here

3:07

with all the inflammation around it.