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With this next case,

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we're gonna review how to obtain annular measurements using a manual method.

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And by a manual method,

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I mean we're not gonna use the software assistance to define the annular plane.

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Rather we're gonna take standard NPRs to find the annular plane and make our

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measurements. We're gonna start,

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I'm just using my standard PACS system here and we're gonna open up the patient

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in N P R mode that allows us to make double O bleak measurements for this

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particular, uh, video. Please ignore the, the red line that's, um,

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not relevant to these three windows that we're gonna use.

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The red line defines this window in the upper left-hand image,

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which we're actually not gonna use for our measurements.

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So what I recommend starting with is starting with the nice short axis view of

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the valve. And so what I tend to do,

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and actually let me zoom this up just a little bit.

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I tend to start with a coronal view here,

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so I'm gonna scroll on the coronal view until I see the valve in profile.

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So here you go. You see the valve leaflet's coming together,

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you'll notice that there's a little bit of blurring with this image and that's

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because these are the 20% phase. Remember I mentioned, um,

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if you watch the videos that we should be generally selecting from the 20%

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phase, these tend to be a little bit more motioning. Um,

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as far as the phases of the cardiac cycle, if you find that there's so motion,

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you can't use them and certainly you can use another systolic phase which has

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less motion artifact. That's fine. Okay,

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so I start with this coronal view and then I drag my cross hairs. So my,

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my three points to the center of where the valves come together.

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And now the next step is I wanna make a oblique and I wanna oblique this axial

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plane counterclockwise such that it's parallel to the

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aortic valve. So you see just like that,

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the counterclockwise motion makes this axial plane now parallel to the

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aortic valve.

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Now what I'm gonna do is I'm gonna take a look at my other long axis view.

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So this is the coronal long axis view.

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This is now the sagittal long access view here and do the same thing.

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I'm gonna repeat this by putting my cross hairs in the middle of the aortic

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valve and adjusting my planes to make sure that I am parallel to the aortic

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valve. And that seems to be about right there.

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Now if we look in the upper right hand corner here,

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we've got the short axis view. So you've got long axis, long axis, short axis,

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and from the short axis view you can see the three different valve leaflets.

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And you can actually really nicely see here the restricted valve opening.

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So this is in systole and you can see there's not very much valve area that

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leaflets are really kind of stuck in the almost closed position for this

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particular patient. Now what do you do next? Well,

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next you want to make sure that your valves are relatively symmetric,

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which they are in this particular case.

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And then what I do is I scroll down towards the annulus.

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Now remember the annulus is right where the valve leaflets insert on the left

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ventricle. And as I scroll,

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I wanna make sure that the valve leaflets maintain their symmetry.

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And so if they're not, then you can make some adjustments.

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So for instance, in this case,

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I noticed that the right and left cusps here are a little bit smaller than the

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non coronary cusp.

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And what you can do is if you place your cross hairs in the middle and

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create a plane that's bisecting right through that cusp that you think is a

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little bit off center,

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you can then go to one of your long axis planes and adjust so that the cusp

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comes a little smaller. So in this case,

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what I typically do honestly is just kind of do a, a manual kind of movement,

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a little bit of a tweaking here and there and see what happens.

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So I'm gonna adjust this a little bit and see what that does.

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Moving that plane changes the size of my right leaflet and my left leaflet.

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So actually that's not what I wanna do. That's not quite the right thing.

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So instead I'm gonna go to this other plane,

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the coronal view and make some adjustments there.

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And I see as I move this plane and I tilt it clockwise and counterclockwise,

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I'm actually in effect making the non coronary cusp bigger and smaller.

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So again, I wanted to make it more symmetric, so I'm gonna stop right there.

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I think that's pretty symmetric with those right and left cusps.

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And so when I find that symmetry,

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then I'm gonna march down again towards the insertion of these cusps on the L V

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O T and they still look symmetric, still look nice and symmetric.

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I'll keep marching, keep marching.

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Now it looks like this right cusp is maybe just a little bit smaller than the

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others.

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So I'm gonna see if there's any adjustments I can make that can fix that.

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So here I adjusted this bottom right image,

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a little bit counterclockwise and that improved the symmetry of my cusps.

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Now I'm gonna adjust a little bit more and things look pretty good,

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a little bit more. And then boom, you're out of the cusps, right?

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They all disappear and if you're in the right spot,

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they should all disappear at exactly the same time from your view.

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And once they do, then you know you're in the annulus.

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Now what are the checks that you can do?

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A check you can do is you can just sort of rotate around in this long

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axis plane and make sure that your annular plane is actually touching the bottom

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of the leaflets.

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And the way you could do that is if you grab any of these planes from the

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short axis plane here and start doing a clockwise rotation,

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then just keep your eye on the prize down here in the bottom right and look at

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where your plane is relative to the bottom of those

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leaflets. That's also called the nadir of the leaflets.

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And usually make sure your plane is touching the bottom as you rotate all the

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way around the clock there. And I think we did a pretty good job.

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I'm very happy with that. Here I am, for instance,

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at the bottom of this leaflet here and it looks like we're right at the bottom.

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As I rotate a little bit more,

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I see that we're at the bottom of this leaflet right here.

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We seem to be well positioned there.

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And then here we're at the bottom of that guy as well.

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So I think we're in a really good spot.

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I'm gonna blow this up and then I'm gonna make my measurements with this

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Particular pacs. Um,

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you've got different choices for the ways you can make measurements.

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So I'm going to choose to um,

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actually do a freehand measurement as best I can.

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The other way you can do it is with a sort of like placing multiple points kind

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of approach. Um,

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that's another way this freehand measurement's a little bit sloppy sometimes,

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depending on how sort of steady your hands are.

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And I probably didn't give you the best job this time. The other approach,

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like I said,

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is you could do an approach where you place multiple points and it does kind of

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a curved measurement along the points

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and there you go.

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That gives you the perimeter and then you usually wanna get an area

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as well. And also you wanna do measurements.

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So I do a long axis measurement and then I take the perpendicular to that long

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axis measurement. So I go with those two measurements.

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And then you would also want to do whatever tool it is that you need to do the

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area measurement as well.

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So that's how you arrive at a manual measurement of the aortic valve annulus.