0:01

So this case is an example of two things.

0:03

It will show you some of the areas where we would've potentially called a stenosis

0:08

with the prior NASA criteria that we would not call with the current IAC criteria,

0:14

and also an example of 50% to 69% stenosis.

0:17

So on the right, you can see that as we kind of go through the common carotid

0:20

artery, we are seeing some areas of plaque.

0:23

There's some shadowing calcified plaque here.

0:27

And as we move up through the bulb,

0:30

you can see continued shadowing plaque.

0:33

And then when we move to the proximal ICA, in this case, we do not see any clear

0:38

velocity elevations in the proximal portion.

0:40

But once we get to the mid portion, we do actually start to get a little bit

0:44

elevated over that traditional threshold of 125.

0:49

Same thing that we see in the distal portion.

0:51

But what you see is we actually have a pretty wide open vessel here.

0:56

We can see some areas of plaque and some shadowing for sure, but we don't really

1:01

see anything that really looks like it's nearing 50% of that vessel lumen.

1:05

So this is a good example of a case that would've been potentially over-called by

1:11

the prior criteria, but the newer criteria would kind of just classify as less than

1:15

50% stenosis.

1:18

On the flip side, as we go towards the left, you can start to see as we move up

1:23

through the common carotid artery to the bulb, here we have some pretty dense

1:27

shadowing plaque as we get into the bulb.

1:30

And then as we get to the proximal ICA, we're starting to see, again, now we see

1:35

some true elevations in the velocity.

1:37

We're getting close to that 180 centimeter per second threshold, and then here we

1:41

start to exceed it, so we get over 200 centimeters per second.

1:45

So this would be consistent with a 50% to 69% stenosis.

1:49

And then as we get further down, it gets even more pronounced.

1:52

We're now over 208, and so we're starting to get closer and closer to that

1:57

degree of stenosis that is truly hemodynamically significant, which is over 70%.

2:03

Again, this doesn't quite get there, but it's showing you kind of that progression.

2:07

It kind of gets a little bit more normal as we get to the more distal portion, but

2:11

there's a pretty clear area where you can see narrowing that looks a little bit

2:15

more representative of what you would expect.

2:18

As we get to the distal portion, you can see kind of a more return to a more normal

2:23

appearing velocity. This is still kind of above the older criteria of velocity

2:28

thresholds here, but you can see that there's a significant change.

2:32

And this is much more representative as we go back of what we would expect to have

2:36

a stenosis that was closer to 50%. You can see the actual compression in the lumen

2:41

here, whereas on the previous one, it didn't really look like it was narrowed at

2:44

all.