Robert J. Cionni, MD
Robert J. Cionni, MD
Are we better surgeons than our predecessors? I don't think we are. However, we can say without a doubt that technology has improved tremendously. Thus, outcomes have improved-also tremendously-for the vast majority of our patients. But as with almost all advances in technology, there is a downside: Patients today have much higher expectations than they did in the past. Every time we take a step forward in technology, we create higher expectations and have to provide patients with better outcomes. Nowhere is that more important than with our cataract and refractive surgery patients. We have to provide them with a very safe, uncomplicated procedure and with excellent uncorrected vision postoperatively.
Consider first the issue of safety, beginning with the fluidics on the INFINITI® system, which in turn will lead us to the AquaLase® system. Compared with the older Legacy system, the new pump in the INFINITI® vision system has less compliance. Because there's less compliance, we can have a very predictable rise time. This can hasten the vacuum buildup, or slow it, so you can be aggressive or conservative and be equally happy with this machine. In addition, the INFINITI® system can provide true surge protection-anticipating occlusion break, slowing or stopping the pump-and thereby prevent the sudden surge that can lead to iris or capsular damage.
Let me outline my technique for the use of the AquaLase® system on cataracts between grades 1 and 3: I start with a good hydrodissection. I want this lens to be mobile. I typically divide the lens into 2 halves using sculpt settings. The fluid is directed into the center of the lens by pointing the tip toward the spot where I want to create the groove. The AquaLase® pulse fluid will move forward and delaminate the nucleus, eventually creating a groove in front of the tip. I keep the bottle at 80 cm for sculpting; aspiration rate is 30, and the rise time is 0-we don't need a fast rise time when we're not trying to gain occlusion. The vacuum is at 80 mm Hg, and I use linear control of magnitude, although most of the time I have my foot all the way down on the pedal so I'm usually at 100%. For sculpting, I use 45 to 50 pulses per second (pps) and set the burst somewhere between 80% and 100% as well. You can sculpt deeply with the AquaLase® handpiece, having confidence that even if you burst through the posterior nuclear plate, you're much less likely to break a capsule than you would be with ultrasound.
After I've divided the nucleus, I switch to my chop setting, which is a higher vacuum and higher flow setting. The bottle goes up to 90 cm, the aspiration rate remains at 30 cc/min, but now the rise time is 3. So for brief periods of time the aspiration rate will increase up to 60 until I get near maximum vacuum levels, then it drops back down to 30. The vacuum is at 400, and I have linear control of my magnitude, which I generally keep between 20 and 50. The pps is set at 45 to 50, and the burst is set between 40% and 50%.