Zhen Xu: From a noise complaint to histotripsy

2:42let's start with a noise complaint that helped set a remarkable discovery in motion. Our first story is from noise complaint to cancer treatment recognizing Dr. Jun Shu the Lee Kashing Endowed Professor of Biomedical Engineering at the University of Michigan. Umish uh in the early 2000s Shu was a graduate student in the late professor Charles Ka's lab uh unfortunately he passed away in 2020. They were investigating ways to remove heart tissue using ultrasound and the

3:24idea was to help children who had congenital heart disease without open surgery which would obviously be incredible. Uh but the experimental setup was so loud that her labmates started to make some complaints. So she tried changing the pulse sequence to quiet it down. And when she tested those pulses on pig hearts, she saw something remarkable which was that the tissue was breaking apart. That observation helped launch more than two decades of work by Shu and her colleagues to develop hystotripsy. one of my favorite names for an area of

4:05study with funding support from the National Institutes of Health and the Department of Defense. Now, this is a great visual labeled bubble cloud uh of what we're talking about here. So, historic uses short intense pulses of focused ultrasound to create a cloud of tiny bubbles in targeted tissue. As those bubbles expand and collapse, they physically break the tissue apart. All without an incision. And that's what we're looking at here, which is just an incredible visual. >> Absolutely incredible >> to understand. And the the complexity of this just blows my mind. >> Yeah. >> So, Shu and her colleagues co-founded Histoics in 2009 to help bring this

4:47technology to patients. Again, starting from a place of just trying to make the labmates happy because there's a little bit of loudness happening. Um, its Edison system received FDA authorization in 2023 for non-invasive destruction of liver tumors specifically. But the question is, how do you control something uh as violent as the collapsing of bubbles precisely enough to use it inside the human body? Yeah, I mean it's it's an incredible question that first you have to like control the collapsing bubbles and then you have to move it around. If you go back to that video that you just showed, right? There's a bubble that you've somehow

5:28engineered using sound inside of the human body which has tissue so it's not like water where the speed of sound is the same everywhere, right? You've got to control where the bubble is. It can't be too big otherwise it messes up all the other tissue that's nearby. you've got to control where it is and you have to control the duration otherwise it's going to kill or cause heat and things like that. Um, fundamentally it's kind of a physics question. >> Mhm. >> Right. Um, how do you actually do that?