0:01

Okay, let's take a look at some prostate anatomy.

0:04

In the sagittal projection, in the midline,

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the patient is lying on their back.

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So this is going to be anterior,

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this is going to be posterior.

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And you've got the base, the middle of the

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gland, or mid-gland, and apex of the gland.

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You can see this curious angle from

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anterior proximal to posterior distal of the

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urethra, and then it goes straight on down.

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Here's the central urethra

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and the periurethral tissue.

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And then we've got the fibromuscular

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zone, which is pretty thin.

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In the midline.

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This is a midline diagram.

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So we're going to help you through the

0:40

transition of anatomy off to the side when we

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look at a live MRI where the anatomy changes

0:46

a little bit and the peripheral zone becomes

0:48

more prominent but stay tuned for that.

0:51

Around the urethra you mostly have the TZ or

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transitional zone portion of the central gland

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depicted here in yellow and it's probably a

1:00

little bit of TZ Uh, behind the urethra as well.

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So let's put a little yellow over here too.

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So some more TZ.

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And then in orange we have the CZ.

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So together these make up the, the central gland.

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Now as you get older, unfortunately, the

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central gland, and especially the central

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zone, gets bigger and bigger and bigger

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and starts to encroach on the urethra.

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So you can have trouble urinating.

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And also we have structures

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that we haven't drawn in yet.

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Like this one in purple, the seminal vesicle.

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So it'll start to press

1:39

against the seminal vesicle.

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And then anteriorly we've also got the bladder.

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We have the bladder right here.

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towards the base of the bladder.

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And it'll lift the bladder

1:52

up and indent the bladder.

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And sometimes when you have really profound

1:56

BPH, it'll get kind of fluffy and lobulated and

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it'll start to look a little bit like broccoli.

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Now let's take this anatomy and let's

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rotate it into the projection that

2:09

you're going to look at with MRI.

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Now for those of you MR aficionados,

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which hopefully all of you are, let's

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look at the sagittal projection in the

2:19

way that you would view it as an imager.

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So this would be anterior,

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this would be posterior.

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Here's your bladder.

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And we've got the urethra coming down

2:29

from the bladder right here, making

2:30

that angle that we talked about.

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And around the urethra, in the midline,

2:36

is gonna be the transitional zone, or TZ.

2:40

Gonna have a TZA and a TZP.

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And then we've got the central

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zone, which is posterior superior.

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And it's this one.

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Along with some TZ hypertrophy, they

2:50

can get really, really big and start

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to press on the base of the bladder.

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And sometimes it'll even be kind of

2:55

fluffy, a little bit like broccoli, and

2:58

may even encroach upon the seminal vesicle.

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And of course, encroach upon the urethra,

3:03

along with the TZ, which gets bigger

3:05

and causes difficulty in urination.

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In the midline anteriorly, we've

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got the fibromuscular tissue.

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Which on T2 is going to be dark.

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We're not going to show that just yet.

3:17

And then in the back we're

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going to have the, the PZ.

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Now as we go off to the side, the PZ

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is going to wrap around everything.

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So PZ tissue, as you go more lateral, is going

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to take over from the fibromuscular zone.

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And is going to be the predominant

3:33

zone in the periphery, in the

3:35

most lateral cuts on either side.

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You're going to appreciate that on MRI.

3:40

So, so have no fear.

3:41

Now Basic, basic, body coil,

3:45

sagittal, T1 weighted image.

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Um, I've got the stubby little

3:49

seminal vesicle right here.

3:51

Just to orient you, here's the spine in the back.

3:53

Here's the bladder in the front.

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Here's the pubis in the front.

3:57

Here's the pre-prostatic space of Retzius.

4:01

Here is the, the rectum.

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And between the rectum is kind of a

4:04

slit-like area, the Denonvillier fascia.

4:07

The rectoprostatic space.

4:09

But I'm actually showing it for the PZ.

4:12

Because this patient had a biopsy.

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So the biopsy has produced blood.

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And the blood is isolated to the PZ.

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How cool is that?

4:23

So there you see your PZ kind of hooking around.

4:27

Going very deep and apically.

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And cancers occur there.

4:32

When you biopsy the prostate, because the

4:35

cancers are very dense and firm, the blood

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tends not to extrude into the cancer.

4:41

That's known as the prostate exclusion sign.

4:46

So you've got blood infiltrating all around

4:49

the PZ, except in two separate cancers.

4:52

So this patient has cancer, but I'm

4:54

showing it for the shape of the PZ,

4:58

and then you see the rest of the gland.

5:01

Which is relatively faceless on a

5:03

T1 weighted image, which includes the

5:05

fibromuscular zone or anterior stroma,

5:08

the TZ, and the CZ posterosuperiorly.

5:12

Let's move on, shall we?