0:00

Okay, let's look at PI-RADS' designation

0:03

for T2 imaging on MRI.

0:07

And we're going to focus on the axial

0:09

projection using fast spin echo technique.

0:13

And then we're going to use the sagittal

0:15

and the coronal to modify not only the

0:19

shape, but the degree of mass effect and

0:21

location of the abnormalities that we depict.

0:24

So I'd like to work off

0:25

the axial projection first.

0:27

And just refresh you with a diagram.

0:30

So let's start out.

0:31

I'll use the color purple to draw the

0:34

central region of the prostate gland.

0:38

And in front of that central region, you're

0:40

gonna have an anterior fibromuscular stroma.

0:45

And then the central region of the gland consists

0:47

of a transitional zone and a central zone.

0:51

Let's make the central zone green.

0:54

It's gonna be up high near the base.

0:56

But as you go down, there's no central zone.

1:00

Within the TZ.

1:01

In other words, it's all

1:02

transitional zone as you go down.

1:04

But as you see, the central zone up high

1:07

occupies a lot of the periphery of the gland.

1:10

There's not much peripheral zone up high.

1:14

So let's pretend we're at the top

1:16

of the gland near the bladder.

1:18

So what's our peripheral zone look like?

1:20

It looks something like this.

1:21

We'll draw it in pink, and

1:23

it'll look something like that.

1:27

So there really isn't as much peripheral

1:29

zone at the base in the midline because

1:31

the central zone really occupies that area.

1:35

So we'll kind of draw in the central zone.

1:38

So as we get a little bit lower, the

1:40

peripheral zone comes to occupy a

1:42

greater and greater degree of this area.

1:45

I'm not going to draw in each axial projection.

1:49

The transitional zone also occupies more of

1:51

this central area, and butts out or pushes away

1:55

the central zone.

1:56

So the central zone essentially disappears.

2:00

Now in the sagittal projection.

2:03

In the sagittal projection, let's draw

2:04

our central portion of the prostate gland.

2:08

Which consists of a posterosuperior

2:12

central region, or central zone.

2:16

And now let's draw our peripheral zone.

2:22

It kind of makes the letter J.

2:24

Now when you're near the midline, as you get up to

2:26

the top, there really isn't much peripheral zone.

2:29

It's occupied by the CZ, or

2:32

central zone, seen here in green.

2:35

And then, just for completion's

2:36

sake, we should draw the anterior

2:40

fibromuscular stroma in the front.

2:41

And for interest, just so you're

2:42

oriented, the bladder's up here.

2:44

And then the urethra comes

2:45

down and then goes forward.

2:47

So, we're talking about this area right here,

2:51

from top to bottom, and this area right here, in

2:55

the midline, and following it off to the side,

2:58

making sure that we focus on all the signals,

3:01

all the way to the apex of the peripheral zone.

3:04

So now let's braid.

3:07

71 00:03:09,390 --> 00:03:10,620 That entire peripheral zone

3:10

is uniformly hyperintense.

3:13

No nodules, no masses, no wedge abnormalities

3:17

A2.

3:19

A two would be a linear or wedge-shaped

3:21

hypointensity, or diffuse, mild, non

3:26

mass-like hypointensity on T2 FASP

3:29

and Echo with an indistinct margin.

3:32

So, let me draw the peripheral zone again.

3:35

Let's make a central zone, and

3:37

then let's make a peripheral zone.

3:40

So something that is fan-shaped or wedge-shaped.

3:43

would be considered a 2.

3:45

If the gland was uniformly slightly lower

3:48

than signal intensity throughout, that

3:50

would also be another example of a 2.

3:55

And there is no mass effect

3:57

from any of these abnormalities.

3:58

In other words, they're non-mass-like.

4:02

How about a 3?

4:03

A 3 would be heterogeneous intensity,

4:07

or non-circumscribed, ill-defined,

4:09

but rounded in shape. Moderate

4:12

hypointensities, or I like this even better.

4:16

It includes anything that doesn't

4:17

meet the criteria for a two, a four,

4:20

or a five or a one for that matter.

4:22

So it's a tweener.

4:25

So now you know what a two is.

4:27

You're about to find out what

4:28

a four is, and a five is easy.

4:31

So anything that doesn't fit

4:32

into 1, 2, 4, or five is a three.

4:34

We're talking just T2-PI RADS designation in

4:39

the PZ or peripheral zone on Fastmen Echo T2.

4:43

Let's go for our score number four.

4:48

Circumscribed, homogeneous,

4:50

moderate hypointensity as a mass.

4:53

So it's mass-like, confined to the

4:55

prostate, no surgical or anatomic capsular

5:01

transgression, and it doesn't involve the

5:03

neurovascular bundle, and it's less than 1.

5:06

5 centimeters in dimension.

5:09

So if we drew that, it would

5:10

look something like this.

5:12

Central zone, peripheral zone, 1.

5:16

5-centimeter nodule.

5:19

It can abut the capsule, peripherally, or not.

5:23

It can abut the surgical capsule, or not.

5:27

It is more ominous if it crosses

5:29

either of these two boundaries.

5:32

But, for all intents and purposes, a score

5:36

of four must not have any evidence of

5:38

crossing the peripheral and anatomic capsule.

5:43

Let's go to a five.

5:44

Five's easy.

5:45

It's just a four, but bigger.

5:47

Now, it's greater than 1.

5:49

5 centimeters in dimension, usually 2 centimeters

5:53

in size, and or, there is trans-anatomic capsular

5:58

spread or invasion into the neurovascular bundle.

6:02

So let's have a look.

6:03

Let's draw again.

6:04

We've got the central portion of the

6:06

gland, which is made up of the TZ and CZ,

6:10

and then we've got the peripheral portion

6:11

of the gland and the axial projection.

6:14

So our 5 would be, oh, close to 2

6:18

centimeters in size, or, it's over 1.

6:22

5 centimeters, or it's crossed this boundary, so

6:26

it has crossed the anatomic capsule, or it has

6:30

decided to invade the neurovascular bundle and

6:33

then face the fat that surrounds these little

6:36

dots that make up the neurovascular bundle.

6:40

So that is the scoring system for T2, VASP

6:44

and echo imaging in the peripheral zone

6:47

using the axial projection for scoring.

6:51

And then you would go on and look at the various

6:54

appearances of the shape of this abnormality in

6:58

the sagittal and even in the coronal projection.

7:00

For what may look non-mass-like in one

7:02

projection, in the coronal projection,

7:05

let's say this is the coronal, it could

7:06

pop out of the capsule superiorly.

7:08

And you might miss that in the axial projection.

7:11

You're going to use all three

7:12

projections to decide location, size,

7:18

mass-like character, and transgression.

7:21

Key anatomic areas like the anatomic

7:24

capsule and the neurovascular

7:26

bundle.