GOOD PREDICTABILITY

The precision afforded by the FEMTO LDV Z6 power plus femtosecond laser in the creation of clear corneal incisions for cataract surgery and astigmatism correction can translate into more predictable visual outcomes than is achieved with standard cataract surgery, said Bojan Pajic MD, PhD, FEBO, Reinach AG, Switzerland. “The FEMTO LDV Z6 results in a highly predictable quality resection for cataract surgery with a significantly smaller range of visual acuity and significantly less induction of higher-order aberrations compared with conventional phaco,” he told the 18th ESCRS Winter Meeting in Ljubljana.

In a study involving 48 eyes of 24 patients who underwent cataract surgery with the Femto LDV Z6 (Ziemer) femtosecond laser in one eye and conventional phacoemulsification in the other, the mean visual acuity at one month’s follow-up was around 0.85 in both groups (p=0.47), but the standard deviation was significantly wider in the conventional phaco group than in the femtosecond laser group.

In addition, while higher-order aberration RMS did not change significantly from baseline onward (p=0.10) in the femtosecond laser group, there was a significant difference in the higher-order RMS postoperatively than preoperatively among eyes that underwent the conventional procedure (p=0.014). Dr Pajic noted that compared with some other femtosecond laser platforms the Femto LDV Z6 is easily incorporated into standard cataract surgery suite. It therefore does not require the patient to be moved. The laser combines adjustable low nanojoule pulse energy delivered at a frequency above 5.0 MHz.

PRECISION PLANNING
As with all femtosecond laser systems, the planning of corneal incisions with the FemtoLDV 6 requires not only biometry and topography but also pachymetry, particularly in eyes where arcuate corneal incisions are indicated. The laser’s clear corneal incision module for cataract surgery is designed for the creation of one main and up to two side-port incisions. The cuts can be made along one, two or three planes, it is said three different shapes.

“These cuts take about 80 seconds at the moment but the new algorithm will decrease that to 40 seconds or less. What is good is that there are no tissue bridges, so even the side-port incisions are open,” Dr Pajic said. The laser also has an arcuate incision module with nomograms for up to three arc-shaped incisions. In two patients with 2.0 D of astigmatism preoperatively, the cylinder decreased to 0.66 D on day three and 0.4 D at day 10 and remains stable till one month postoperatively at 0.53 D after the creation of arcuate incisions with the laser.

“Our nomograms for arcuate incisions will be undergoing some fine-tuning over the next few months as we treat more patients, but the results we’ve achieved so far are quite good,” Dr Pajic said.