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Welcome to MRI online's discussion of pituitary

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protocols. I'm here with my partner, Dr.

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Malcolm Schupack. I'm the younger one,

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he's the smarter one.

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Let's take a look at the pituitary blood supply.

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We've got a sagittal view of the pituitary gland.

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And let's look at the inferior hypothalamic artery,

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which is coming in from the back.

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And it's going to provide the supply to

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the posterior aspect of the gland,

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which consists of the median eminence,

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the infundibulum and the pars nervosa.

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Now, the front of the gland receives its supply

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from the superior hypothalamic artery,

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which comes in anterosuperiorly,

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and it comes in mostly in the hypothalamic region.

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And then a portal plexus of vessels descends to

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supply the anterior gland, which, by the way,

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consists of a pars tuberalis,

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which is a little bump at the base of the stalk.

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And then the rest of this anterior gland consists of

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the pars distalis or the anterior pituitary gland,

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which I'm coloring in here.

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So I've got inferior hypothalamic artery in the back,

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superior hypothalamic artery in the front,

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descending as a portal plexus.

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Now, to understand how to image the gland,

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of course you want coronal imaging.

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You want T1 and T2 imaging to

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assess large lesions in the gland.

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But when you're searching for microadenomas,

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you want to look at the Turkish saddle,

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which is the pituitary fossa region,

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and we look at the gland,

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which will make aquamarine blue here.

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We'll color it in.

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And we want something that's pretty dynamic.

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And what I mean by that is we want to look at the flow

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into the gland in less than 30 to 45 seconds,

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because if you wait too long,

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you could miss a microadenoma.

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So a microadenoma is often off to the side,

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a little bit in the wings,

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because that's where the prolactin cells are located,

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a little bit off midline.

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And in the middle of the gland,

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you're going to have something called

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the vascular pituitary tuft,

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and you're going to look for displacement

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of that tuft to one side or the other.

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Now, to get this dynamic effect optimally,

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you want fast, three-dimensional imaging,

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much like you do in the prostate gland using

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a dynamic injection of gadolinium,

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so that you're getting an image about

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every 15 or 20 seconds over say,

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a half centimeter or 1 cm distance of the gland,

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so that you might be imaging the gland at, say,

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ten to 15 seconds, and then 15 to 30 seconds,

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and then 30 to 45 seconds,

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and then finally 45 to 60 seconds.

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Now, if you do that,

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you're going to see the microadenoma as a cold object

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and the rest of the gland will be warming up or

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enhancing. Then you might get a delayed image.

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And that delayed image could be done with 3D,

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or it could be done with two-dimensional.

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T1 spin echo. And this little object here,

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which was cold, may reverse itself, and over time,

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it may accumulate contrast, and all of a sudden,

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it will become hot or warm.

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So it will change from low signal to high signal.

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And that's another reason why you

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don't want to wait too long.

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You want to be early in the game so that you can see

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the pituitary microadenoma as cold and

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the rest of the gland is warm.

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Now,

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for those of you that don't have 3D,

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just get a three or a four-millimeter one, two,

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or three-slice view right in the middle of the gland,

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right through the pituitary tuft,

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and then perform your dynamic injection.

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Do it relatively quickly so that the

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scan time is 30 seconds or less,

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and then get your delayed image so you'll

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have one pretty early dynamic image,

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and then you'll have 160 to 90 to 122nd

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image using the 2D technique.

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And that way you'll see this phenomenon of cold

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converting to hot for a pituitary microadenoma.

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And don't forget to throw in your coronal T2 or an

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axial T2 just in case you have a macroadenoma

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that's going off to the side or something that's

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going up in the supracellar region.

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How's that sound?

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Good. Great. Let me make another comment.

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One thing that I think we're going to be focusing on,

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you're going to see as we get to the case review is

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something we used to be really sensitive to when

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we were kind of CT and plain film guys,

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and that is the size and shape of the sella.

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Okay, because that has a lot to do.

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We're going to talk about the surgical approaches as

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well. How are we going to treat some of these?

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Should we save that for the anatomic discussion?

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Yes. Well, let's do that.

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And we'll we're going to also follow up on a

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couple of things you mentioned here.

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Great.