Nashville, TN | Ultrasound-Free All-Laser Cataract Surgery | Wang Vision Institute
This is Dr. Ming Wang from Nashville, Tennessee, describing a case of ultrasound-free all-laser cataract surgery. As you see, this is a lens nucleus has been pre-laser chopped by a LenSx femtosecond laser and I'm using a cannula filled with Viscoat to push the anterior capsule towards the center. The pearl here is to start proximal towards the center and then push to distal. The reason for that is that if you start this tall, then you will stir up the cortex and proximal is most difficult to plot. Now I'm going with a, you try the forceps and making sure that everything is all freed and pull it out.
This ultrasound-free all-laser cataract surgery technique is basically taking advantage of the fact that LenSx femtosecond laser can actually fragment the lens in vivo, inside the capsular bag. Here is the hydrodissection, and so we basically, you see the whole lens nucleus has flowed into the anterior chamber. So as I said, this technique is taking advantage of the fact that a femtosecond laser can fragment the lens in vivo, inside the capsular bag. And so then, however, it is still enveloped in the epinucleus. The lens is still one piece. It's just been pre-chopped by the laser inside the capsular bag. Here, I'm using a cannula filled with Viscoat to basically elevate, making sure the whole piece in the anterior chamber push back the posterior capsule. You see that when I put a cannula behind it, you see the cylindrical and the crosshair laser chop pattern done with this LenSx femtosecond laser. And so I put some Viscoat also in front of it to protect the cornea endothelium.
This ultrasound-free all-laser cataract surgery technology is basically that is a technique to take advantage of the lens fragmentation capability laser. Here you see spatula and the big ball, what I call the sessile instrument my cracker. I basically anterior posterior apposition crack the lens nucleus into small pieces. What I found that the femtosecond laser does more than just simply make a cut in the nucleus substance. Because it is a shockwave as we know is a plasma generation, a generation of 10 to the 23rd or something like that, a number of electrons in a very small volume, and the shock wave push, plasma wave push the pieces of tissue aside. It actually softened the lens tissue adjacent to the laser cut. Now you see actually the center piece and this is a center. Typically, as you know, in most of the cataract, this is the hardest piece. So I'm kind of going to pause here just to show that this is a femtosecond laser pre-chopped piece of the nucleus.
As I said early, what we discovered through the development of this ultrasound-free all-laser cataract surgery technology, now I've chopped a piece into now, is that the laser does more than just simply make a cut in the nucleus tissue. It actually softened the lens tissue adjacent to the plane of the cut due to the shockwave, plasma wave tissue separation mechanism. Here, I'm just using the cracker to cracking and opposing and so all the pieces basically end up into very tiny little pieces. I think this is much more efficient than standard phaco chop in the sense that in a standard phaco chop, you have two instrument, the phaco tip and a chopper coming from the same direction. Since we're in the anterior chamber, we have the second instrument can go behind the material, so you can actually oppose each other 180 degrees. Here, we are left with basically anterior chamber full of smallest fragments of the lens. So as I said that this technique, as you know, works well because the ability to AP apposition to fragment those lens pieces since the lens is anterior chamber.
Now I put some Viscoat behind and in front to protect the cornea endothelium. And so I'm going to go in there in a moment with my phaco tip. The key, another pearl for this ultrasound-free all-laser cataract surgery technology is that the phaco tip needs to be bigger in its bore size. Standard phaco tip is 0.9 millimeter, but I use the biggest one that is available. That is 1.1 millimeter in diameter in phaco tips. Of course such a large bore phaco tip is not very safe to do, to use in the capsular back, but for the anterior chamber approach, of course, there's not a concern. Now I see very efficient appositional technique. The reason I need to shake the phaco tip is because to generate some turbulence swirl of the current so to help those pieces come into the port. Basically, you just repeat the same action that are far away from the posterior capsule.
Here is at the end of the case. For time's sake, I jumped to the end. You see that even, beautiful capsular eye is well-centered, 100% circular, and even overlap with optics, which obviously has going to really great to help us for the effective lens position and the final refractive power. Those are the unique capability of the femtosecond laser.
This is a case of ultrasound-free all-laser cataract surgery technology, taking advantage of the ability of laser to fragment the lens in vivo. This is Dr. Ming Wang from Nashville, Tennessee.