0:00

Now this will be my last, uh, sector map vignette,

0:04

and I wanna draw your attention to the lateral

0:08

or sagal orientation first,

0:11

and you'll appreciate that the axials are oblique so

0:14

that they're perpendicular to the long axis of the gland.

0:18

Uh, some people are fanatical about that.

0:20

There's a little bit of disagreement,

0:22

and some people just do them as straight axials so that

0:26

that can be a story for another day.

0:29

But there are going to be three major axial

0:32

sector map appearances,

0:35

and these include the base up high, the middle

0:40

or mid, and then the apex down low.

0:43

So that's very self-explanatory,

0:45

and there are going to be some differences.

0:47

At the base, you're gonna have a fairly substantive

0:50

transitional zone, and you'll have a TZA

0:53

and A TZP, an anterior and posterior portion of it.

0:57

You're also going to have a PZA and A PZP

1:03

and A PZL.

1:05

So here's the PZA right here.

1:07

Here's the PZL for lateral, and here's the PZP.

1:11

So you know, kind of medial right near the midline.

1:14

And then one major difference is at the base,

1:17

you're gonna have a fair amount of central zone,

1:21

which is this green area,

1:22

and it's gonna wrap around the ejaculatory ducts.

1:26

So that's not gonna be present to any degree or substance.

1:30

As you move down, you'll, you may see a little bit

1:32

of the central zone with the ejaculatory ducks in the mid,

1:35

and I'll show you that in a minute.

1:37

You're always gonna have in the front the anterior

1:39

fibromuscular zone, which is hypo intense,

1:42

and I have it here in blue,

1:43

but in many respects, it can be very difficult to separate

1:47

that out from portions of the anterior transitional zone

1:51

and portions of the anterior peripheral zone.

1:55

As we get down lower, let's go to the mid gland, right

1:57

around this level, the middle of the gland,

2:00

very self-explanatory.

2:01

We've got all the same areas,

2:03

but we've got a lot more PZ tissue.

2:06

Now the PZ tissue in a young, healthy individual is gonna be

2:09

hyperintense on a T two weighted image,

2:12

and the transitional zone area will be more hypo intense,

2:16

and you'll be able to separate them one from the

2:19

other in a healthy gland.

2:20

This area of separation between the transitional zone

2:24

and the peripheral zone is called the surgical capsule.

2:29

Now, it's not a true capsule,

2:31

but you will see a hyperintense interface between the two

2:35

as opposed to the anatomic capsule,

2:38

which is not a true capsule,

2:40

but this fibroelastic tissue around the outside.

2:43

So you're gonna have two capsular designations.

2:46

One is the surgical capsule

2:48

and one is the peripheral capsule.

2:50

Now I use this surgical capsule when I have a lesion in the

2:53

TZ and its lenor,

2:55

and it goes right through the surgical capsule. It

2:59

Completely disrespects that surgical capsule

3:02

that pushes me way in the direction of an aggressive lesion

3:06

of RAs four or a RAs five.

3:09

Again, notice the peripheral zone is gonna be bigger at the

3:12

mid-level, and we're gonna have the same areas.

3:14

We're gonna have A-P-Z-A-A-P-Z-L,

3:18

which is more posterior and A PZP, which is more medial.

3:23

Then. Now let's move

3:24

to the apex down low in the lower third of the gland.

3:28

Pretty self-explanatory.

3:30

I don't need to go into the PZ anatomic designations again,

3:35

but look how much smaller the transitional zone is,

3:38

and the anterior fibromuscular zone is gonna be a little bit

3:42

bigger, and you are going to intersect

3:46

the peripheral zone with the fibromuscular zone.

3:50

As you can see in the sagittal projection, that is harder

3:53

to appreciate in the axial projection.

3:55

So you'll need to wiggle your eye back

3:57

and forth between this projection

3:59

and this projection

4:01

to help decide whether an abnormality is really coming from

4:03

the peripheral zone, or you're just seeing some

4:07

fibromuscular zone tissue,

4:09

or whether you have an abnormality from the peripheral zone

4:11

that is working its way into the fibromuscular zone,

4:15

all the way up the front of the gland, which does happen.

4:19

So three basic axial sector appearances,

4:23

one at the base, one at the middle of the gland,

4:26

and one down low at the apex of the gland.

4:31

That concludes our discussion of sector map evaluation

4:35

and anatomy.