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Okay, in this video, we're going to review an approach

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to reading coronary CT and discuss

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the various case components in

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series you're going to see when you're looking at these studies in ombra.

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so first you'll probably when

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you pull up the study, it's probably going to default to the Scout which you

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know, we know we get

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an initial topogram and all these studies and then I just want to go through the

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different series that we have before we start looking at the images. So,

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you know what you're dealing with.

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Most these cases are going to have a stack of

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calcium scoring images that we've acquired before the exam.

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And then you'll see the second series is a series of

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three millimeter thick slices.

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after contrast

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things are actually not something that's particularly important for you

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to review that actually on our end used

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by our technologist to assess initial kind

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of quality check after the studies performed.

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Then you'll see that we have actually two different sets of these 0.75 millimeter

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thick slices. These are the diagnostic scans.

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One of them is going to be in

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a more kind of soft tissue kernel and that's

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the first one and then the second one is actually going to

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be in a sharp reconstruction algorithm. So you'll notice a lot more noise. And

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this is something we do by default and include in patients

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all of our patients for coronary CT. It really

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helps with evaluating patients with heavily calcified plaque and

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stents.

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Finally, then you're going to see this stack here of the

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one millimeter thick slices with a whole lot of images in

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this case 1200 images. This is our stack of

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multi-phase data.

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We use one millimeter slices just to reduce the amount of

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images that end up going to our archive. You'll notice

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as you put the patient's images in that you're

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going to be scrolling through multiple phases.

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In the cardiac Cycles. So as you learn more

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about if you attend the one of

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our other courses going over the technical aspects

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of cardiac CT one, we acquire create CT

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will often get images throughout a portion of the cardiac cycle

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and we can divide up those images into multiple different phases. So

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this data here is actually a stack of

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data from multiple different phases.

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In this case because the patient had a very low heart rate at

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the time of examination. You can actually see all the images here look pretty much Diagnostic in

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terms of quality, but in some cases with patients

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with higher heart rates, you'll start to see a little more artifacts within

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different phases. And so they'll

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be a couple cases where

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Later on in the course. I may actually refer to some of the

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other phases just to show you how they can be helpful with sort

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of complete evaluation the patient.

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But for the vast majority of these cases, you'll really only

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need to use these 0.75 millimeter slice thickness images

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for the evaluation.

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Then finally we've got three millimeter lung Windows three

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millimeter soft tissue Windows. These are all with the big

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field of view just to evaluate for any extra cardiac findings. This patient

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has a hiatal hernia for instance and then you'll see down there's

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a calcium scoring documents and biotechnologist which shows

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the calcium score and then finally some Recon

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some standard Recons. We always do curve planar images

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of all the vessels with a full spin. So we've got

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the right corner artery.

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LED and circumflex and

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then what's also very helpful for evaluation is our technologists

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will make some short access reconstruction images.

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And some long axis images as well.

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And so the goal here really is that

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from all the source data both the

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axial images as well as the cprs short

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axis and long access images.

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That you can get the majority of the information you need without having

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to do too many multiplayer reformats, which

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I showed you in the previous video.

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Those the different series that we have just real quick

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review of how I would approach a coronary CT. Basically, I

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because you know, I'm a radiologist. I'm used

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to Distributing things on axial. I always start with the axial images and I

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just go level by level into the different

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segments that coronary arteries and the corners themself. So I'll start

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with the elf mean review it for any plaque and

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then move on to the LED and the LED. I'm going

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to look at both the branches on in this case. Here's a diagonal Branch.

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This is a septal Branch here adding the other direction.

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I'm going to look at all the branches and then follow the LED all

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the way out to its termination.

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On this case. It's kind of a small LED gets really small towards the Apex.

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That's okay. That's pretty normal.

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And then repeat for all the other vessels once I've

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done my axial assessment. Usually then I'll go

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to another assessment. You always want to make sure that you

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look at all the vessels and at least two views if

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not more. So what I would usually

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do then is follow up by looking at the CPR images of

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the LED and carefully reviewing for

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any areas of plaque that I might have missed on the excellent images and then

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do this repeat the same for the circumflex and

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also for the RCA.

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And you'll notice that we're not capturing all the corners here

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where our cprs are following the main vessels,

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but we don't follow the diagonals or other branches. So

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that's where these short axis and long axis reconstructions

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come into play. I can look here on the

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short axis at the left main I get a really nice

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look at the circumflex here in the left AV

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group.

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I get a nice look at the RCA and the right AV Groove.

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I can see the branches of the RCA coming out of me. Here's

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the posterior descending artery. Excuse me right here. And then

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I also see the LED and the LED branches in this

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case a diagonal Branch here coming right out at me so I can look

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at those end on.

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And then finally if you go to Long axis views.

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You can then get a look at more of the branches.

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In this case, I find a long excess

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views really helpful for looking at the LED and profile. So

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here we see left knee into the LED and profile

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and in particularly wrapping on the Apex when it's

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a large enough.

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And then most useful of all I think for these

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long axis images is to look at the branches of the circumflex

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those obtuse marginal branches here here.

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And smaller branches over here. This patient actually has a

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kind of small left side of system. So we don't see the branches very

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large but these small circle obtuse marginal

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branches over the lateral wall.

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A lot of times this long axis image does a really good job of

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showing you those branches and then so if I find that all those things

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look normal that I'm happy, you know, I can report this study as a

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normal case.

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You know if I'm ever confronted by any stenosis that

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I want to work up any further than I may go back to the axial images

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and then start using the NPR analysis.

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Which I showed in the previous video how to

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do that NPR analysis on ombre. So for instance, you

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know, you can make some different NPR views just to

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really drill down on a certain aspect of the coronary

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artery that you're interested in.

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So that's a quick overview of how best to approach these

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coronary CT images.