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Dr. P here.

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3 00:00:02,390 --> 00:00:03,730 Got myself an eight-year-old

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male who stepped on a splinter.

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Many of you would go right to

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ultrasound, since it's pretty superficial,

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and that's totally reasonable.

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We're here to talk about MR today.

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MR is awesome for a foreign body assessment.

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11 00:00:19,890 --> 00:00:23,510 However, there are two take-home messages here.

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One, you've got to be in the right plane.

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What is the right plane?

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Well, you don't know that because you don't

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know how the foreign body is shaped or oriented.

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So your best bet is multiple planes.

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Another option for you is to acquire in 3D.

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And this way you can angle your

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plane in any direction you want.

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Now one favorite 3D sequence by this reader

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is the Gradient Echo 3D.

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And I particularly like the Adage

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the Additive Gradient Echo Sequence

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because I can get 1mm slices

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and I can orient it in any

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projection that I wish to get in line

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with something that say is linear like a

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splinter to make sure that it's not some

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septum in the fat or some other artifact.

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Now, in this case, we didn't do that.

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And that's disappointing to me.

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It wasn't done at our facility.

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However, that would have been ideal

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to have a gradient echo image.

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So another very important take home

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message is the 3D gradient echo

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can be extremely valuable

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when you're hunting for a body.

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Still, we've gotten a water weighted image

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right here on the left in the long axis,

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so called sagittal or lateral projection.

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And as you look very carefully, all you have to do

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is use what I call the Santa Claus technique.

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Santa knows where all the good girls and bad

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girls are and good boys and bad boys are. At MR,

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when you have some hyperintensity, that's

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where the bad boys and bad girls are.

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So you look for that hyper intensity

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on the fat suppressed proton density

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image, and you're gonna get there.

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And when we do that, we concentrate on this area,

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and lo and behold, as we scroll around, near

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the gelatin capsule marker, we run into this

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thing, which is not a septum within the fat.

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It's just too darn straight.

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I mean, a septum will branch off.

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And then you try and corroborate

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it in another projection.

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Now, in this long axis, coronal

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projection, you're not going to be

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as en face or parallel to the lesion.

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You can see that there, but you're going to

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catch part of it, and there it is, right there.

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I'm going to put my little circle pen around it.

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Just so you see it, right there.

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I don't like the color brown for this.

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I like something like yellow.

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And there is my splinter.

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Here is my splinter.

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Now when you go to the wrong pulsing sequence,

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look at what you have on the T1-weighted image.

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You have a soup of gobbledygook.

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It is very difficult to tell

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where that splinter truly is.

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Let me throw up a couple of short-axis images.

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Here's one.

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Here's another.

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Remember now, you're in the

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short axis to the splinter.

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So the splinter is now going to appear as a dot.

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But all you have to do is follow

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the bouncing high signal intensity.

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What I call the Santa Claus sign.

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We find where the bad girls and

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bad boys are, right there.

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Right smack dab in the center of it is going to be your

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splinter in the short-axis projection.

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And here it is, right there.

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I'm going to draw over it right now.

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There's your splinter.

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And of course, here's all the edema and swelling

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around it that directs you to the proper location.

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The T2-weighted image

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is not quite as easy to ascertain the splinter.

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So once again, we illustrate that pulsing

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sequence, projection are the important factors

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in helping you tease out these small lesions and

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especially not shown the gradient echo 3D, one

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of which is the additive gradient echo sequence.

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Let's move on.

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Shall we?

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Dr. P out.