Comparison of visual and corneal aberrometric outcomes and depth of focus between transepithelial photorefractive keratectomy (TPRK), laser-assisted in situ keratomileusis (LASIK) and small incision lenticule extraction (SMILE)

Session Details

Session Title: Corneal Refractive Surgery

Session Date/Time: Tuesday 17/09/2019 | 14:00-16:00

Paper Time: 14:30

Venue: Free Paper Forum: Podium 3

First Author: : A.Koshy INDIA

Co Author(s): :    R. Shetty   A. Sinha Roy   Z. Dadachanji   G. Kundu                    

Abstract Details

Purpose:

Corneal laser refractive surgeries have become the preferred choice for many who restrain from the use of spectacles or contact lenses. Depth-of-focus of the eye is the range of distances over which visual acuity performance is maintained. One potential topic that remains to be fully addressed is the effect of such refractive surgeries on depth-of-focus. This study thus aims to quantitatively evaluate visual outcomes, anterior corneal aberrations and accommodative response by analyzing the dynamic changes in refractive powers and wavefront aberrations post refractive surgeries.

Setting:

This was a prospective interventional study conducted at Narayana Nethralaya: a tertiary level Superspeciality Eye Hospital, Bangalore, India.

Methods:

75 eyes each, who underwent LASIK, SMILE and PRK surgery were included in this study. Visual acuity assessment was done preoperatively and at 6 months postoperatively. Corneal topography and aberrations were evaluated with Scheimpflug imaging using Pentacam HR preoperatively (pre-op) and at 6 months post operatively(post-op). Using the iTrace Ray tracing aberrometer/topographer, pre-op and post-op refractive errors and wavefront aberrations at target distances of distant, 60cm and 40cm were measured. Post-operative visual acuity (VA) and aberrations was assessed for each accommodation in each group.

Results:

64.5% patients showed Gain of 1 line in TransPRK as compared to 44.8% in LASIK and 54.2% in SMILE. From distant to near accommodation, spherical power decreased significantly (P<0.0001) from -0.25±0.05 (mean ± standard error) to -1.62±0.04D in LASIK, from -0.29±0.07 to -1.41±0.05D & from 0.04±0.18 to -1.38±0.12D respectively in SMILE and PRK. Defocus increased significantly (P<0.0001) by 0.61µm, 0.58µm and 0.5µm in LASIK, SMILE and PRK from distant to near accommodation. Results when compared with age-matched emmetropes showed similar trends.

Conclusions:

Although TransPRK, SMILE and LASIK use different algorithms, all 3 procedures were comparable in terms of safety and efficacy in our study. The surgeries also had similar aberrometric outcomes. With respect to VA post refractive surgeries, PRK performed better in distant while LASIK performed better in intermediate and near accommodation. Across the 3 groups from distant, intermediate to near accommodation, Defocus increased significantly with accommodation. When compared with age-matched emmetropes, LASIK seemed to closely mimic the Normal group.

Financial Disclosure:

None