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Hi, everybody. Thank you so much for that intro, intro, uh, introduction.

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I'm Emily Ambinder. I'm a breast radiologist at Johns Hopkins.

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I'm really honored to have been invited to be here today.

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I wanna thank Modality and M r I online for, um,

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allowing me to give this lecture and for helping me put the, um,

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presentation together. I have, um,

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I've no disclosures. Um, this is just a, an outline for the talk. I know it's,

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it's a case-based lecture, but I am gonna start with, um,

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a little bit of a didactic section on tomosynthesis.

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Then we'll move to some screening and diagnostic cases. Um,

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I'll briefly talk about utilization of tomosynthesis and then move towards, uh,

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tomosynthesis guided biopsy and tomosynthesis guided biopsy cases.

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So digital breast tomosynthesis, or D B T was, um,

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approved by the F D A in 2011.

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So with D B T we acquire multiple images of the breast,

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which are then reconstructed into thin image lys that can be viewed

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individually.

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The resulting image is quasi three D allows us to see a lot more detail than our

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traditional three D mammograms. And, um,

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I wanna point out that this is quasi three D and often, we'll,

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we'll interchange the term three D mammogram with D B T,

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but it's not a true three D mammogram.

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We're not taking perpendicular slices of the breast like you would have in a CT

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scan. We're taking angled images across the breast, and this is a, um,

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an image kind of that, that's demonstrating that.

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So this is from the Hologic website, but the blue circle represents the breast.

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And you can see in a mammogram that that is compressed between the detector

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and the compression board, which are in green.

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The x-ray tube at the top in red will rotate around the patient

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and take these angled images, and the images are then reconstructed. Um,

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so you can scroll through the individual slices.

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Um, so what are the benefits of tomosynthesis? So it's really a win-win.

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So when we are doing screening mammography with digital breast tomosynthesis,

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we find that we have a lower recall rate by having fewer false positives.

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We have a higher cancer detection rate by finding more true positives.

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So it's higher sensitivity and higher specificity. There's,

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there's not that many, um, technologies that will improve both of these,

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uh, metrics. Um, I can't help myself but just show the,

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the calculations for sensitivity and specificity is just something I'm really

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important to, um, understand when talking about, um,

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especially screening exams. So sensitivity, uh,

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in order to improve that would be by making sure that we're really finding all

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of the true positives and minimizing our false negatives. Um,

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so that's gonna be an improved cancer detection rate with specificity.

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We really, um, want to limit our false positives.

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So that's what we're doing by decreasing our, our recall rate.

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Um, so how does the recall rate get, uh,

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decreased using tomosynthesis will as i'll,

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I'll show in several cases we're really able to mitigate our

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Uncertainties due to overlapping breast tissue when we're using tomosynthesis.

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Um, there are, you know, lots of different numbers kind of thrown up.

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I think generally we accept that the screening recall rate is decreased by about

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15% when we're using, uh, D B T for screening mammography.

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So what about increased cancer detection? Well, with, with D B T,

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we're also able to see more detail in the breast,

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and studies have shown that we have, um,

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an improved cancer detection of invasive cancer specifically by up to 40% when

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we're doing screening mammography using chemosynthesis. Um,

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it is actually been shown to be,

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be beneficial in all breast tissue density categories,

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but it's particularly helpful in dense breast tissue.