Liquefaction device is good alternative for cataract surgery

August 15, 2005

Miami—Cataract surgeons performing standard ultrasound phacoemulsification will find the AquaLase liquefaction device (Alcon Laboratories) is an easy technique to transition to and is one that offers multiple advantages for enhancing the safety of lens removal, said Sonia H. Yoo, MD.

The AquaLase device, a feature of the Infiniti Vision system (Alcon Laboratories), uses heated fluid pulses propelled from the tip at a rate of up to 50 pulses per second to strain and emulsify the cataract rapidly.

Because the AquaLase device involves no mechanical motion at the tip, there is no heat build-up from friction. Therefore, the risk for thermal incision burns is potentially eliminated, she said.

Technique adjustment

Based on the angle and configuration of the fluid propelled from the AquaLase tip, surgeons who switch from conventional ultrasound to this technology may need to adjust their technique by steepening their angle of attack and creating a larger bowl versus a groove in initial sculpting. Dr. Yoo noted that some surgeons use a prechop ("Aqua-chop") technique with the AquaLase device. However, she favors an approach in which she creates an initial sculpt-groove, then cracks the lens, and removes the nucleus. She then proceeds with cortical clean-up using the AquaLase tip.

"The cortical material can be cleaned up using the familiar I/A technique, but I usually find it can be done without having to switch over to an I/A handpiece," Dr. Yoo said.

To demonstrate the efficacy and safety of the AquaLase device, Dr. Yoo and colleagues at Bascom Palmer undertook a retrospective review of outcomes for 22 consecutive eyes of 20 patients with 3-month follow-up data. Almost all cataracts were 2+. Denser nuclei (3+) were not included, but otherwise there were no inclusion or exclusion criteria.

Data collected on OR time indicated the AquaLase device had no adverse effect on efficiency.

"We were understandably concerned that it might take the nurses a little longer to set up when changing to a new technique, but the transition did not cause a significant delay," Dr. Yoo said.

The visual acuity results were very favorable. At 30 days, best-corrected visual acuity (BCVA) was 20/20 or better in 83% of eyes and 20/25 or better in 100%. Uncorrected visual acuity (UCVA) was 20/30 or better in 70% of eyes and all achieved 20/40 or better UCVA.

No significant adverse events were encountered. Most eyes had only 1+ or trace flare and cells on day 1. At month 1, a single patient had rebound iritis that was attributed to rapid steroid tapering. The iritis responded to an increase in the steroid dose and remained controlled after a slow taper. At 3 months, four patients showed evidence of trace or 1+ posterior capsular opacification (PCO).

"The AquaLase device seems to offer the potential to reduce PCO significantly because it can be used safely to polish the capsule and enhance removal of equatorial lens epithelial cells," Dr. Yoo said. "Therefore, as we look forward to the availability of injectable lens materials where PCO could not be treated with the Nd:YAG laser, we would like to see if we can modify the technique such that PCO would be eliminated."

Endothelial cell counts were also measured and showed average changes from baseline of –122 and –227 cells/mm2 after 30 and 90 days, respectively.