The Deeper - The Better? Truth Or Myth? Clinical, Molecular And Imaging Perspectives In Outcomes Of Smile Surgery

Published 2022 - 40th Congress of the ESCRS

Reference: PP21.04 | Type: ESCRS 2022 - Posters | DOI: 10.82333/bt34-9p26

Authors: Savitri Deval* ¹ , Rohit Shetty ² , Pooja Khamar ¹ , Sharon D'souza ³ , Bhavya Gorimanipalli ²

¹CATARACT AND REFRACTIVE SURGERY,NARAYANA NETHRALAYA EYE HOSPITAL, BENGALURU, INDIA,BENGALURU,India, ²CATARACT, CORNEA AND REFRACTIVE SERVICES,NARAYANA NETHRALAYA EYE HOSPITAL, BENGALURU, INDIA,BENGALURU,India, ³CORNEA AND REFRACTIVE SERVICES,NARAYANA NETHRALAYA EYE HOSPITAL, BENGALURU, INDIA,BENGALURU,India

Purpose

To evaluate the effect of different SMILE cap depths on postoperative visual outcomes, optical quality, corneal nerves, healing and dry eye parameters.

Setting

Patients visiting Narayana Nethralaya, Bengaluru on a out-patient basis, who had refractive error and were seeking refractive surgery opinion for the same, were shortlisted based on their scans and recruited in the study after obtaining well informed consent.

Methods

A randomized, prospective and comparative study was undertaken, wherein contralateral eye of 40 subjects (80 eyes) undergoing small incision lenticule extraction (SMILE) surgery on Visumax (Carl Zeiss) laser platform were included. The cap depth was chosen to be at 100 microns in one eye and 150 microns in the contralateral eye respectively. The outcomes assessed were postoperative vision, optical quality (OQAS, Visiometrics), epithelial thickness (CSO OCT MS-39), sub-basal nerve plexus changes (In-vivo Confocal Microscopy), tear fluid molecular factors and dry eye parameters. The subjects were followed-up and examined at post-operative 1 week, 1 month, 3 months and 6 months.

Results

Both groups showed comparative visual recovery over the follow up period. Eyes with 150 microns cap depth showed earlier sub-basal nerve regeneration than those with 100 microns depth, but the overall nerve density was similar at the end of 6 months. No difference was noted in epithelial healing and optical quality outcomes. Transient dry eye was noted in both the groups. Tear molecular factors showed slightly elevated inflammatory factors in eyes with 100 microns cap depth in the early postoperative period.

Conclusions

Different cap depths in SMILE could influence early and late post-surgical outcomes by its impact on corneal nerve regeneration, inflammation and wound healing.