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With this next video we're gonna review how to measure the vessels for vascular

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access planning. In this case,

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we're gonna use a specific type of three D post-processing software.

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All software is a little bit different in terms of appearance,

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however they all use the same kind of core approaches.

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And what we've done with this particular piece of software is create a center

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line right here.

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And this is used to create what's called a curve planar reformatted image.

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That's this sort of stretched vessel image that extends from the mid aorta

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down to the proximal superficial femoral artery.

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This patient has very little disease as you can see,

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so when I'm assessing this patient,

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I would say that there's very mild calcification.

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You can see a few flexive calcium here and there and that.

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As far as the tortuosity goes,

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a lot of times I like to use a volume rendered image to assess that.

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So in this particular case,

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if I'm assessing the tortuosity from this volume rendered image,

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I would say it's very minimal, right?

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These commonly acts are are very straight and then the left and right external

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iliacs have just a mild curve to 'em, but that's to be expected, right?

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That's really normal as it's coursing along the um, pelvic sidewall there.

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So really no significant tortuosity and very, uh,

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mild calcification for this particular patient. Now,

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as far as the measurements go, we do measurements on a segmental basis.

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We do minimum diameters for the aorta,

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for the common iliacs,

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and then for the external iliacs and the common femorals,

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generally the axis is going to be at the common femorals,

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right at the level of the um, femoral head.

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This nice sort of angio view can show you there.

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Usually I think they want to get in somewhere around the bottom of the femoral

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head.

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That way they can apply pressure against the femoral head after taking out the

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catheters to make sure that the patient heels up the hole,

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that they've placed the heels up fine.

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So usually the target is somewhere around the common femoral artery depending

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on, you know, where the bifurcation of that vessel is. Alright,

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so as far as the vascular evaluation goes,

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usually what I do is I take a look on the short axis view first and I try

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to assess just sort of as a general kind of visual assessment of

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where is the smallest vessel diameter. And I'll just go visually.

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You can see there's little outlines from the automated segmentation.

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It's done with this software.

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But I have to say the automated segmentation often works great as you can see

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here. But for some more marginal cases or heavily diseased cases,

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it may not work perfectly.

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And so I usually go with my eyeball first and then use the automated

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segmentation to, you know,

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assist me after I've sort of made my own decision about where I think the

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minimal diameter is. So in this particular case, you know,

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I think the diameters are quite large for this aorta.

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I think it looks like there's a couple calcifications here that are gonna narrow

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the vessel a little bit.

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This automated measurement shows me it's about 11 millimeters up higher.

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I've got another couple of calcifications here,

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which are narrowing the lumen a bit.

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That's also measuring around 11 millimeters.

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So we're gonna call our minimal diameter for the aorta 11 millimeters.

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Now we're gonna move on to the common iliac here.

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And as I scroll through the common iliac,

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I'm just again gonna keep an eye on the actual vessel diameter,

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just eyeballing it. And I see very minimal disease, not a significant narrowing.

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And so it looks to me like the mine diameter,

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probably right around what that little bit of calcium is around seven

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millimeters. Then when I go through the external iliac artery,

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again doing a visual assessment,

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looking for what seems to be the most narrow aspect. It seems like there's,

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you know, pretty much a uniform size throughout,

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maybe just a slightly gentle increase in size as we get distally,

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which is pretty typical for this external iliac artery.

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Usually the minimal diameter is somewhere here around where it's curving.

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So in this case we've got a diameter around five,

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which is pretty typical for like a smaller older woman around five

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millimeters. Pretty typical number. Now,

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if the video before about vascular access,

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I mentioned that six is usually what we wanna see in this case is five,

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meaning that they're not gonna be able to use this patient's vessels.

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Actually probably not a five in a good looking vessel,

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meaning very little calcification,

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very little tortuosity is usually still gonna be okay for their purposes. It's,

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it's when you have a five millimeter vessel and a a lot of disease that you

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start to get concern may go with other approaches. And then finally,

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I'm gonna scroll through the external iliac artery to the bifurcation of the

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common femoral artery and then go upwards a little bit.

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So how do I know when I leave or I transition from the external iliac artery to

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the common femoral artery where I look or where the vessel leaves the abdominal

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wall and heads out into the groin area. So that's,

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you can see here on the long axis image,

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it's somewhere around this spot right here.

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And then I look at the common femoral artery and uh, again,

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I make an assessment in the upper left hand corner here looking at the degree of

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calcification and it looks like it's fairly mild. And again,

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the minimum diameter around six millimeter. When you're doing these,

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you'll see that you get,

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often get a lot of calcium and the common iliacs relative sparing of the

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external iliacs, and then a lot of calcium in the common femorals as well.

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And we just tend to measure inner diameter.

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You wanna measure from the inner luminal wall to the calcium or whatever disease

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you have and measure the minimum diameter.

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That's the most important thing that's gonna determine what vessel they can use.

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What other thing I like to point out,

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you may have access to pay on your software to a stretched view,

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which you have here. This particular software,

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it does a stretched vessel view and that's just a nice way also of assessing

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diameter. You can see it's pretty uniform throughout here,

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but if you saw any areas of significant narrowing or stenosis,

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you could right away kind of jump to those areas and do a measurement.

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These are sort of automated measurements that are popping up here,

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but certainly you can do your own manual measurements depending on, you know,

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what you have access to

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And, you know, you can do, uh, just a standard measurement, um, you know, if,

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if that's what you need to do with whatever software you're using. And again,

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we wanna measure from inner wall to inner wall to get the, uh,

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most accurate measurement.

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And so that summarizes the basic approach to doing these vascular access cases.

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I'm only gonna go through the right,

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we don't need to go through the left as well. It's the same process.