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Now I'd like to talk to you briefly about dynamic

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contrast enhanced MRI

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and there is some debate about its value

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and its need, um, across the pond.

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Our, our friends in Germany produced a, a fairly large study

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that showed there was very little change in the PY RADS

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grading and the overall outcomes of a patient with dynamic

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contrast enhanced MRI.

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Others believe that it,

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it can be invaluable in certain circumstances,

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and you can read about those circumstances in the PY Rads

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V 2.1 document whose link is

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provided in this series of vignettes.

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So a negative enhancement pattern.

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After you inject

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and remember, you should be producing dynamic

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contrast enhanced images on A 3D GRE

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in the axial projection.

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And then each dynamic temporal

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slice should be less than 12 seconds.

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We tend to average around seven

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or eight seconds per dynamic temporal slice.

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So negative, no early

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or contemporaneous enhancement, that's easy

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or diffuse multifocal enhancement

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that does not correspond to

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any focal finding on a teach two weighted image

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that makes sense, or there's no focal DWI restriction

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or focal enhancement corresponding to a lesion demonstrating

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features of BPH.

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In other words, there is enhancement corresponding

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to a lesion, but that's a typical say,

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BPH nodule on the T two weighted image.

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And in the peripheral zone, those are frequently,

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if they're round, they're gonna be extruded BPH nodules.

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So you have to go back. If you see a nodule in the

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peripheral zone that's enhancing, go back

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and make sure that you don't have the neck

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of the nodule coming out of the transitional zone,

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because this is a very important pitfall

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that can lead you into the over-diagnosis of cancer.

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Now, what's a positive score?

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A positive score is when you have focal

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and earlier than the other tissues enhancement.

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And this corresponds

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to a suspicious finding on the T two weighted image

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or the DWI.

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Now, in some respects, this is a lot like breast imaging.

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You know, if you have phase number one, all of a sudden pop,

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you have a quick rapid enhancement in the first

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7, 8, 12 seconds after injection,

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before anything else appears.

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And it matches up with say, a T two weighted abnormality

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that's lent deform in the transitional zone

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and kind of smears the tissues like a bagel.

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Or you have a nodule in the, in the peripheral zone

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that is not an extruded BPH nodule and

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or you have DWI restriction along with that

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or associated with that area of enhancement.

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You've got a positive. Now, when can this be valuable?

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It's valuable when you're noodling around a PI RADS three

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on your by parametric assessment.

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In other words, you've used the T two, you've used the TDWI

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and you've come up with a PI RADS three designation.

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If you have this additional dynamic enhanced, uh,

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sequence and it's positive, then it's a three

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plus one or it's a four, so it would become a PI RADS four,

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and many people use it that way.

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Let's move on, shall we?