0:01

The following is a patient who presents, uh,

0:03

for surveillance looking for hepatocellular

0:07

carcinoma as a history of cirrhosis.

0:10

So we'll jump right ahead to the T1

0:12

post-contrast fat-saturated images.

0:15

I'm gonna scroll down.

0:16

There's a few lesions here, but the one I want

0:18

you to pay attention to is this one down here.

0:21

So this is, of course, the T1, uh,

0:23

post-contrast fat-saturated image.

0:25

This is done in the arterial phase.

0:28

Now we can see this lesion over here at the

0:30

periphery of segment 5, and we notice that it

0:32

has non-rim arterial phase hyperenhancement.

0:38

So unlike some of the other lesions that we've

0:41

discussed up to this point, which didn't have

0:43

arterial phase hyperenhancement, this indeed

0:45

does have arterial phase hyperenhancement.

0:47

That sort of categorizes it into, uh, a

0:50

group of potential lesions that it could be.

0:52

We can measure the size, and if

0:53

we were to measure this, we'll see

0:55

that it's less than 10 millimeters.

0:57

The next step is to see whether it has any of

1:00

the additional features that will allow us to

1:03

qualify this as a hepatocellular carcinoma,

1:05

a BI-RADS 5 category or even a 4 category.

1:08

And to do that, we need to look at

1:11

our remaining post-contrast images.

1:13

This is T1 FATSAT post-contrast in the portal

1:16

venous phase. This is the same thing in the

1:18

equilibrium phase. This is that arterial

1:20

phase image. Again, we have that image

1:22

lesion here. That's arterial phase hyper-

1:25

enhancing. It's less than 10 millimeters.

1:27

If we look at the approximate location of the

1:29

portal venous phase, very difficult to find.

1:32

It's probably iso-intense.

1:33

You don't see it on either of these phases.

1:36

So there's no washout, there's no

1:38

pseudocapsule, no washout associated with this.

1:41

We don't have a prior to see

1:42

if there's any interval growth.

1:43

And so based on that, this would

1:45

qualify as a BI-RADS 3 lesion.

1:50

This is a patient who would then get a

1:52

subsequent MR or CT exam in about 3 to 6

1:56

months to see what happened to this lesion.

1:58

And, uh, you know, somebody may look at

2:00

this lesion and say, well, why doesn't this

2:02

represent a FID that we talked about before,

2:04

that transient hepatic intensity difference?

2:06

After all, it's at the periphery, it's arterial

2:08

enhancing. It becomes iso-intense on the, um,

2:12

portal venous and equilibrium phase images.

2:14

And if, if desired, you

2:16

know, one may call this a FID.

2:17

However, FIDs typically

2:19

are much more wedge-shaped.

2:20

If you look at this very subtly, there are

2:22

rounded borders associated with this.

2:24

So when you start to see those rounded

2:25

borders, it's best to sort of qualify this

2:28

and evaluate this lesion as something other

2:30

than a FID so you can get close interval

2:32

follow-up to see if it grows or changes its

2:35

appearance on the subsequent imaging studies.