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So this vignette is about, what do we name the baby?

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What is the zone nomenclature for a prostatic mass?

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And we're gonna start right out in

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the middle of the prostate gland.

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We have a central gland, surgical

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capsule, peripheral zone, or gland.

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In the central gland, we have

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the transitional zone, or the TZ.

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We're gonna have one on the right and one on the left.

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So here's the TZ on the right.

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And here's the TZ on the left, and

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you can see it's a pretty big area.

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And we're going to divide that up into two.

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We're going to have a TZA and a

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TZP for anterior and posterior.

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And we're going to have one on

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the left and one on the right.

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So we'll have a right TZA,

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right TZP, left TZA, left TZP.

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Urethra's going to be in the middle

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with the periurethral plexus.

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We'll draw it in just for giggles for now.

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We'll say it's right about here.

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Then in the front.

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We've got a lentiform, or arcuate

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shaped structure that's pretty dark.

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We'll give it another color, let's give it yellow.

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And we're gonna have the anterior fibromuscular stroma,

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or anterior stroma, also known as the AS region.

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So we're gonna have right AS and left AS,

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and they, they do meet in this region.

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And then we have the peripheral zone

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at the mid level of the prostate gland.

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Now, the peripheral zone is going to

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be divided up into several regions.

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So let's do that with a little

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bit thinner pencil, if you will.

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Let me take a color that works for us.

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Let's try something like purple.

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So we've got the peripheral zone.

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We've got a PZA for anterior.

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So right PZA for the patient's right side.

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Then we're going to have a PZP.

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My writing skills have deteriorated, but there's

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a PZP, and then we're gonna have a PZM, for

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medial or mesial, both mean the same thing.

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And then we run into our little indentation,

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our little raffae in the midline, which

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sometimes can have a little linear low signal

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associated with it, or a little nodular

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low signal, but smack dab in the midline.

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not diffusion restricting, and not vascular.

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So we're gonna have the same anatomic designations

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on the left side as we do on the right.

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Let's go down, shall we?

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Let's go down to the apex of the prostate gland.

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Things get a little more dicey down here.

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It's a little, little tougher to separate things out.

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Let's stay down at a level where we

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can still see some peripheral zone.

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So, this patient, there's a

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little brighter peripheral zone.

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And we're gonna have a, the same designations, PZA.

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PZP and PZM.

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The darker lentiform AS on the

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right, I'm going to color it in.

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I'll make the AS, oh let's make that orange.

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The AS on the right is a little

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fatter than it is on the left.

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So the AS assumes a more prominent position here.

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And the transitional zone is much smaller.

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This is going to be the transitional zone.

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We don't have any central zone down low.

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So the central gland is all TZ.

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So let's color in the TZ.

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And let's use something like blue.

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So here's our TZ right there.

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And we get a suggestion that maybe a

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little urethra there in the center of that.

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Now let's color in the PZ.

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That's the brighter area, the peripheral zone.

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So let's make that red.

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So here's the right arcuate shape PZ.

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And I'm gonna color it in for you.

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The right side is a little bit fatter down low than the

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left side, which is admittedly a little harder to see.

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But it's right there, and you're gonna

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have a PZA, a PZP, and a PZM down low.

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So no central zone in the central gland down low.

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And there's your levator sling and some

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periprostatic fat down low with your rectum behind.

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Now let's work our way up to the prostate base.

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So we're gonna go up to the base.

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Now when you're describing these zones,

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you're gonna say, PZA base, PZA apex.

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So not only are you going to say right versus

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left, not only are you going to say PZA,

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PZP, PZM, but you're going to say base, up

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high, mid, in the middle, apical, down low.

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So now we're up high, and in the posterior superior

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quadrant, up high, you run into some central zone.

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So where is the central zone

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in the central gland up high?

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Gonna be in the back.

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So, let's make that, oh, I like

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green for the central zone.

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Let's get something nice and green.

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And the central zone is gonna be here.

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It's gonna have kind of an arc shape to it.

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And it's, it's really not very

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distinguishable from the transitional zone.

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But that would be about the area of the central zone.

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The rest of this is going to be transitional

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zone, and you get a suggestion along this

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raffae that the urethra is right there.

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So let's color in the rest of the TZ up at the base.

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So we'll use something like brown.

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TZ's going to be pretty big.

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And then up higher, we don't have as

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much anterior fibromuscular stroma.

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So we'll make the fibromuscular

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stroma something like orange.

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It's going to be right here.

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And up high, we're running out of road, so

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we don't see much peripheral zone up high

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in concert with the sagittal projection.

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So, once again, central zone,

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part of the central gland.

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Transitional zone, part of the central gland.

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We'll have a TZa and a TZP.

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And then we'll have the AS, the fibromuscular

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stroma, anterostroma, anteriorly.

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Now for a moment, hopefully you've been

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tracking our progress on the T1-weighted image.

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Thank you very much.

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You can see how faceless the

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prostate is on the T1-weighted image.

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When we get to the base, we

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do see the seminal vesicles.

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They're gonna be gray on the T1-weighted image.

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There's one other thing I'd like to point

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out to you, if we can, we can spot it.

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Do a little train spotting here.

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There's your rectum.

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There's your prostate.

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And the T1-weighted image, along with

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the T2-weighted image, act in concert.

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To show us the status of the anatomic capsule.

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So we're looking for something big and

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gray and dark abutting this capsule.

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The bigger it is, the more likely

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the capsule is to be invaded.

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So when you start to get over 1.

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5 abutment of the capsule, the incidence

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of, of capsular crossing goes up.

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Over 2, starts to dramatically go up.

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Now when you look at the capsule on

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the T1, you're looking at the fat.

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The fat can be a little bit asymmetric.

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If you think you've got fatty invasion, but

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you see nothing on the T2, you're wrong.

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Now there's another structure that fits in

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very nicely in our description of the capsule.

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There's the capsule.

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And then we kind of lose it a little bit.

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But that is not the capsule, right there.

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Let me make it even a little bigger.

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That is the serosa and denovillia

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fascia, the rectoprostatic fascia.

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The T2 is pretty good, the T1 is better in the axial

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projection to show you transgression of that fascia.

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But that concludes our discussion of zonal anatomy.

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Talked a little bit about the capsule.

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The surgical capsule is defined as the junction

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between the central gland and peripheral gland.

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We're going to look for transgression of that.

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When we have central zone lesions, cross it.

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For if you have a charcoal lesion that crosses

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that surgical capsule, you got problems.

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And then you start going into your zonal

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naming anatomy, which we just covered.