Comparison of Measurements and Clinical Outcomes After Wavefront-Guided LASEK Between iDesign and WaveScan

Comparison of the 1st Generation and 3rd Generation Wavefront-Guided LASIK for the Treatment of Myopia and Myopic Astigmatism

Purpose

To compare refractive, visual, and patient-reported outcomes associated with a 1st generation wavefront-guided (WFG) treatment with those associated with a 3rd generation WFG treatment.

Patients and Methods

This retrospective study included patients who underwent femtosecond laser-assisted in situ keratomileusis (LASIK) for myopia/myopic astigmatism. Two random stratified samples of patients who underwent either 1stgeneration (WaveScan, Johnson & Johnson Vision, Santa Ana, CA) or 3rd generation (iDesign 2.0, Johnson & Johnson Vision, Santa Ana, CA) treatment matched on preoperative refraction were compared (4290 eyes of 2145 patients in each group). One-month postoperative visual, refractive, and patient-reported outcomes were analyzed. Refractive and monocular visual acuity analyses were performed using one random eye of each patient.

Results

The percentage of eyes achieving 20/20 or better uncorrected vision was 91.3% (1958/2145) in the 1st generation group and 95.9% (2056/2145) in the 3rd generation group (p<0.01). Binocularly, the percentage of patients with 20/20 or better UDVA was 97.0% (2080/2145) and 99.2% (2127/2145) in the 1st and 3rd generation groups, respectively (p<0.01). The mean postoperative MSE was -0.01 ± 0.33 D in the 1st generation group and +0.19 ± 0.33 D in the 3rd generation group (p<0.01). Postoperative refractive astigmatism had a mean value of -0.20 ± 0.26 D and -0.18 ± 0.24 D in the 1st and 3rd generation groups, respectively (p<0.01). The mean correction index of refractive astigmatism was 1.09 ± 0.53 in the 1st generation group and 1.02 ± 0.38 in the 3rd generation group, p<0.01. The overall percentage of patients satisfied with vision was 92.8% (1991/2145 patients) in the 1st generation group and 97.3% (2087/2145 patients) in the 3rd generation group (p<0.01).

Conclusion

For the majority of postoperative variables, there were significant differences between 1st and 3rd generation treatments. The 3rd generation treatments had better visual acuity outcomes and higher patient satisfaction.

Recent advances in wavefront-guided LASIK

PURPOSE OF REVIEW

Laser vision correction remains an active area of research, and there have been many recent advances in the field. The purpose of this review is to provide an update on the recent advances for one of the most common methods of laser vision correction, wavefront-guided laser in-situ keratomileusis (LASIK).

RECENT FINDINGS

Recent technological advancements in wavefront aberrometry are largely responsible for the improved visual outcomes that have been recently reported. In addition, improvements in femtosecond and excimer laser technology, used in flap creation and corneal ablation, have been shown to provide superior results when compared to microkeratomes and earlier lasers. Wavefront-guided LASIK appears to have advantages over some other keratorefractive modalities in terms of visual acuity, predictability, astigmatism correction, and subjective visual symptoms. Nonetheless, there may be some limitations in highly aberrated corneas, and also in biomechanical stability relative to other available platforms.

SUMMARY

Improvements in wavefront aberrometry, and also femtosecond and excimer lasers, have continued to improve our ability to correct refractive errors. Wavefront-guided LASIK remains a well tolerated and effective keratorefractive procedure, with a trend toward superiority. Nonetheless, further studies comparing this modality to others are needed to define the role each can serve.

Visual, aberrometric, photic phenomena, and patient satisfaction after myopic wavefront-guided LASIK using a high-resolution aberrometer

Purpose

The purpose of this study was to evaluate the visual, refractive, and aberrometric outcomes as well as the level of patient satisfaction and photic phenomena after myopic laser in situ keratomileusis (LASIK) surgery using wavefront-guided (WFG) ablations based on measurements obtained with a high-resolution aberrometer.

Patients and methods

This study was a prospective analysis including 253 eyes of 127 patients (aged between 19 years and 54 years) undergoing WFG LASIK using the STAR S4 IR Excimer Laser System combined with the iDesign System and iFS Femtosecond Laser. Visual, refractive, and aberrometric outcomes during a 2-month follow-up as well as patient satisfaction and photic phenomena were evaluated by means of a questionnaire.

Results

A total of 85% (215/253) and 99% (251/253) of eyes achieved a postoperative (Postop) uncorrected distance visual acuity of 20/16 and 20/20, respectively, and all eyes achieved an uncorrected distance visual acuity of 20/25. Postop spherical equivalent values were within ±0.25 D and ±0.50 D in 97% and 100% of eyes, respectively. Likewise, manifest cylinder was <0.25 D in 97% (245/253) of eyes. A statistically significant reduction was found in the total root mean square (P<0.001) and in the level of primary spherical aberration (P=0.001). Postop difficulties related to vision were graded as minimal, with low levels of photic phenomena and high levels of patient satisfaction. The level of difficulty to perform daily activities and the level of glare perceived by patients while driving car were significantly decreased (P<0.001).

Conclusion

WFG LASIK surgery using the technology evaluated is predictable and effective for the correction of myopia and leads to high levels of patient satisfaction.

Comparison of Visual Outcomes After Femtosecond LASIK, Wave Front-Guided Femtosecond LASIK, and Femtosecond Lenticule Extraction

PURPOSE

To compare the mesopic contrast sensitivity (CS) and higher order aberrations (HOAs) at 3 months after femtosecond-laser in situ keratomileusis (LASIK) (FS-LASIK), wave front-guided femtosecond LASIK (WF-LASIK), and femtosecond lenticule extraction (FLEx) for the correction of myopia and myopic astigmatism.

METHODS

In this prospective nonrandomized study, 332 right eyes of 332 patients were treated with FS-LASIK, WF-LASIK, or FLEx. The HOAs and mesopic CS were evaluated preoperatively and at 3 months postoperatively.

RESULTS

At 3 months of follow-up, 98 eyes (96.1%) of the FS-LASIK group, 92 eyes (98.9%) of the WF-LASIK group, and 133 eyes (96.4%) of the FLEx group had an uncorrected distance visual acuity of 20/20 or better. The HOAs improved from 0.34 μm during preoperative examination to 0.56 μm of the end of the follow-up in the FS-LASIK group, from 0.31 to 0.41 μm in the WF-LASIK group, and from 0.32 to 0.54 μm in the FLEx group (all P < 0.01). At a spatial frequency of 12 cycles per degree, a better mesopic CS was observed in the WF-LASIK group (1.47) than in the FS-LASIK (1.36) and FLEx (1.33) groups (P < 0.01); a better mesopic CS with glare was also noted in the WF-LASIK group (1.37) than in the FS-LASIK (1.25) and FLEx (1.29) groups (P < 0.01).

CONCLUSIONS

The FS-LASIK, WF-LASIK, and FLEx procedures result in comparable refractive results at 3 months postoperatively. However, there is improvement in the mesopic CS and HOAs after WF-LASIK.