Early experience with ELITA femtosecond laser: New technology, smooth entry, precise cuts, swift visual recovery

ELITA, a new femtosecond laser system recently launched in Hong Kong, rates equal to or better than iFS laser in stromal bed quality and ease of flap lift, and offers easy and smooth lenticule removal, according to data shared by Professor Mahipal Sachdev of Centre For Sight group of hospitals in New Delhi, India, at a recent showcase symposium sponsored by Johnson & Johnson Vision.

ELITA is designed for both flap and flapless refractive correction procedures. “For creating a corneal flap in patients undergoing laser-assisted in situ keratomileusis [LASIK], ELITA produces fast and smooth cuts, and induces minimal tissue disruption in the stroma by utilizing the smallest, shortest, and lowest-energy femtosecond laser pulse currently available,” said Sachdev, who was a principal investigator for ELITA’s recent phase III trial.

ELITA’s accuracy of flap thickness for LASIK was evaluated against iFS’s in a prospective, single-site, open-label, randomized clinical study involving 50 patients, where study eyes were treated with ELITA and fellow eyes received iFS. [Sachdev M, ELITA Innovation Showcase, 24 May 2023, Hong Kong]

“This early feasibility study demonstrated excellent accuracy of ELITA compared with iFS in creating flaps for LASIK,” shared Sachdev. “Both systems produced consistent flap thickness, with standard deviations of ±5.6 µm for ELITA and ±6.5 µm for iFS at 3 months. However, ELITA flaps rated better in both stromal bed quality and ease of flap lift in the majority of cases.”

Another study evaluated ELITA-assisted smooth incision lenticular keratomileusis (SILK) intrastromal lenticule removal procedure, which generates a biconvex lenticule shape, for correction of myopia and astigmatism. The prospective, multicentre, phase III, open-label trial recruited 85 adults with uncorrected visual acuity (UCVA) of 20/40 or worse for bilateral lenticule removal. To be included in the trial, patients could have myopia with or without astigmatism up to -12 DS and -6 DC with sum of sphere and cylinder between -1.00 D and -12.00 D using minus cylinder convention. [ELITA Femtosecond Laser Device Manual 0155-3006] Intended correction was emmetropia for all eyes (n=158).

“UCVA was 20/20 or better in 85 percent of eyes at 1 week after the operation, increasing to 96 percent of eyes at 3 months. At 9 months postoperation, UCVA was 20/20 or better in 94 percent of eyes, increasing to 100 percent at 12 months,” reported Sachdev. “Best spectacle-corrected visual acuity was 20/20 in 100 percent of eyes at all postoperative timepoints.”

Mean manifest refraction spherical equivalent (MRSE) was -0.32 D at 3 months and -0.33 D at 6 months after the operation. The standard deviation of MRSE was <0.25 D at all time points, demonstrating very low variability. At 9 months postoperation, 90 percent of eyes had MRSE within ±0.50 D of intended value, which increased to 94 percent at 12 months.

“My personal impression is that SILK lives up to its name, as there were only minor or no tissue adhesions, and all cases [in our study] had complete lenticule removal, with no cold spots, uncut areas or bridges,” said Sachdev. “Furthermore, none of the cases had any difficulty with the entry cut, and plane identification was relatively easy. Corneal biomicroscopy was unremarkable for all day 1 and week 1 postoperative visits. The procedure achieved accurate refractive correction with tight outcomes and standard deviation for both sphere and cylinder. Observed fast visual recovery led to great patient satisfaction.”