 All right, so next up, we have Abed Faroukhi. He is from here at the University of Utah. Originally, he grew up in Orange County, California, went to school at UC Berkeley. He worked the last couple weeks, the first two weeks, he worked with Dr. Jacobian, and is now working with Dr. Moshfar. And we'll be presenting on whether FAKOTIP diameter impacts efficiency in chat. Thank you, Russell. Good morning. My name is Abed Faroukhi. Today, I'm going to be presenting on a research project that I worked on under the supervision of Dr. Olsen as a third-year medical student. And the topic of my conversation today is going to be does FAKOTIP diameter impact efficiency and chatter? So as an overview, I'm going to just discuss the problem that we noted and address the question that we had pertaining to this problem, go over the study design that we employed in our experiment, and then discuss the results that we obtained from our experiment, and then just kind of discuss what we learned from the results. So there's been significant advances in the field of cataract surgery since it began in the 1960s, primarily targeting the components of cataract surgery from the FAKO systems to the settings of the FAKO systems, either the aspiration rates, the vacuum levels, bottle heights, to try to optimize efficiency and minimize complications of cataract surgery. There's also been significant advances in FAKO tips, either whether they're bent or radius, as Dr. Olsen had mentioned in his grand rounds talk a few weeks back. And a lot of these components have been studied extensively through peer-reviewed literature to determine which settings for FAKO emulsification is most effective, as well as which tips are best used in certain patient populations. But in my readings and research, I had not come across any peer-reviewed literature that evaluated the impact of FAKO tip diameters on efficiency of cataract extraction. FAKO tips have been evolving since the beginning of cataract surgeries, mainly to allow for smaller incisions to prevent complications during surgery or after surgery, as well as aiming to increase the recovery time from the surgery. Some of the more commonly used FAKO tips that I've encountered in cataract surgery are the 19 gauge or the 1.1 millimeter. The 20 gauge or the 0.9 millimeters or the 21 gauge or the 0.7 millimeter FAKO tip. Given that there were no peer-reviewed literatures documenting the impact that FAKO tip diameter has on efficiency of cataract, I thought that this project would be a great beginning step to shed some light on the relationship. So my question was, does FAKO tip diameter impact efficiency or chatter during cataract extraction? Efficiency here was defined as the inverse amount of time that is required in seconds to remove the nuclear lens fragment. And it would follow that a low efficiency FAKO tip would require more time for cataract removal and the opposite, a high efficiency tip would require less time for removal. Chatter was defined as a particle bounce of the fragment bounce away from the tip during ultrasound work. So a chatter would cause either increased risk of complications from it hitting the capsule or it could lead to decreased efficiency because of the longer length of surgery time required to remove the nuclear lens fragment. So in my study, we obtained porcine lenses and prepared them according to a previously validated method to resemble human cataract lenses as in regards to its density and behavior during FAKO. The FAKO, we employed three different FAKO systems, a torsional, a transversal and a micro pulse system to study three different FAKO tips. The settings of the FAKO systems were also the same as had been previously studied to maximize efficiency of the extraction. All the FAKO tips that we used were all from microsurgical technology. As I mentioned earlier, we used three different tip diameters, the 1.1 millimeter, the 0.9 millimeter and the 0.7 millimeters FAKO tips. And all tips had a 30 degree tip angle. Unfortunately, there was no 1.1 millimeter tip for the torsional study arm, so we only compared the 0.7 to the 0.9 in that arm of our study. So in my readings, it became evident that there was three main components that were important to cataract extraction, specifically the efficiency of cataract extraction, aspiration flow rate, vacuum levels and FAKO tip movement were the three factors that were very important. So given this, we hypothesized that the largest bore size would be the most efficient, given its advantages with increased vacuum hold, increased fluid flow and a greater ultrasound work per tip cycle movement. Our hypothesis is based on a well-known law, Poise's law, which states that the flow rate is proportional to the radius of the tube to the fourth power. So it follows that a small change in the tip diameter would result in a large change in the flow given that the flow is related to the radius to the fourth power. So a large bore needle would create a larger flow and would theoretically increase the speed of extraction. Also, as I mentioned that vacuum levels plays an important role in the extraction process. So the total hold for any given level of vacuum would be highest for a large bore tip compared to a small bore tip, given that the total hold is directly related to the square of the bore size opening. So we ran the experiment, we ran 24 runs of extraction with each FAKO tip and took the best 20 results. And we came up, these were our results. So you could see that the torsional, which only had the 0.9 comparing to the 0.7, micro pulse and the transversal were the three arms of our studies. We found that in all three arms we had, there was an consistent increase in time required for extraction of the 0.7 to the 0.9 in all three study arms. Only the micro pulse and the transversal showed a statistically significant difference in extraction times and efficiency, but all three had the same trend across the board. We also noted that according to our hypothesis, we thought the 1.1 would be the most efficient however as you can see in the micro pulse and transversal this is not the case, the 0.9 millimeter tips required less time for removal compared to the 1.1 millimeter tips. So these results suggested that the 0.7 millimeter tips were inefficient in removing the cataract in a timely manner, likely because the small tip size resulted in less vacuum level, less vacuum, it generated less vacuum hold and suggests that maybe the lens fragment cannot engage at the tip edge appropriately for removal. Similarly, for the 1.1 millimeter tips, the efficiency was not the greatest because the tip size may have been too large for the nuclear fragment that did not create a maximum vacuum hold level. And so there wasn't enough of us, there wasn't enough of vacuum created to remove the tip, the fragment. This was supported by our results on the number of chatter events. So there is either one, two or three chatter events for each study arm torsional micro pulse and transversal. We only saw a statistically significant difference in chatter events with the transversal arm of our study. However, we looked at these results further and saw that the standard of deviation in each of these results was higher for the 1.1 millimeter and the 0.7 millimeter compared to the 0.9 millimeter tips. The standard of deviation can be thought of as an increase in variability in our results. And this suggests that the increase in variability comes from the poor engagement of the lens at the tip edge. So we refer to this as a micro chatter event at the tip edge and it would result in increased decreased efficiency and longer length of removal time for the lens fragment. For the 1.1 millimeter tip, this micro chatter was due to the poor occlusion of the tip of the fragment at the tip edge. And for the 0.7 millimeter tip, we thought that this micro chatter was due to inefficient net volume hold. So the weak seal at the tip lens interface would create a small five micron micro chatter that reduced efficiency and prolonged extraction time. Combining all of our results, we found that the 0.7 millimeter tip compared to the 0.9 millimeter tip was highly less significantly less efficient compared to any of the other tip sizes. And also we did not see a difference in the statistically significant difference in the lens removal time of the 1.1 millimeter tip to the 0.9 or the 1.1 to the 0.7. However, the efficiency was clearly less for both the 0.7 or the 1.1 millimeters compared to the 0.9 millimeters. So in conclusion, in all three systems that we tested, the 0.7 millimeter diameter tip required the most time for lens removal. That was statistically significant for the micro pulse and the transversal FACO study arms, but the trend was the same in all three study arms tested. And we also noted that the 0.9 millimeter tip was the most efficient and more efficient than the 0.7 and the 1.1 millimeter tips. And so it became evident that in order for effective FACO multiplication, the tip diameter needs to be large enough in order to maintain an appropriate aspiration and suction in order to achieve a maximum vacuum hold. But also it needs to be small enough that the tip edge can be completely occluded with the lens fragment. Some limitations of our studies that it's in vitro in nature and we can't completely replicate what we would see in surgery. And also we used one single size for the lens fragments, maybe using a different size as we would encounter in surgery would yield us different results. But in the future, we can either try to use different size lenses to see how these would respond to different tip sizes. And also all of our FACO systems employed a peristaltic vacuum setting, whereas if we tested this in the Venturi system, the Venturi system has a constant vacuum, it creates a constant vacuum level and that may yield us different results. So here are my references and I'd like to thank the medical students and the residents that helped me with this project as well as Dr. Petty, Dr. Barlow and Dr. Olson for their help and guidance throughout the process. Thank you all for listening and for being here today and do y'all have any questions? Yes. So very nice, a nice piece of work. This all started with a medical student a few years ago, Griffin Jarvee. I told Griffin, I said, you know, there's all of these claims made about cataract surgery and nobody really has objective information relationship with the major companies all going out of A is better to be in LB is better to be in C and wouldn't it be nice to have something more objective? This has been a series of papers that have been ongoing looking at this and two things to point out is they are fairly consistent size which consistent size is part of the reason why we can get good, hard, objective data for two millimeters on the side. That's a pretty good size cube to have that particular size. The other ones is that when we say that they're human, they're human heart and they're on the equivalent of lenses that were taken out from extra cataract surgery so these are three plus plus four plus this is on the limit of what's harder which is we're most, I'm getting the system to soften I mean, a lot of lenses that are used today are vacuum and so strong, you don't need to do so. I think that as you watch it and you see as you can see that particle a clear shadow of balance is off which I think is a danger but you've got to get that in a place it sits in place and it's got the full vacuum now it's got its hold on as long as you don't have enough repulsive force in the tip, it'll stay there and it'll rapidly disappear and it was obvious to me that 1.1 just doesn't have a part of time it needs to occlude that whole area in the 0.9 and there's some objective not this objective information that a lot of surgery group assume that 0.9 would be less efficient I think my times are actually on the fall of people going to 0.7 we've got it stepping back dying to find out when the insuring we've got a little grant and came and got a look at that if insuring has the same results as that because you don't have that need to occlude you to get the full vacuum that possibly then it'll follow what you expect and that is, I know that they asked for a few revisions but we've got our final it's all been taken care of we've got it, is it fully accepted by have not heard back after we submit to the second set of revisions so anyway, we expect that this will be accepted by the factory surgery because the issues they want to change will be very minor so a nice piece of work and the reviews of it were yeah, thank you any other questions thank you all for listening