Comparison of clinical outcomes and morphometric correlation by scanning electron (SEM) and atomic force microscopy (AFM) between low and high energy small incision lenticule extraction

Session Details

Session Title: SMILE: Small Intrastromal Lenticule Extraction I

Session Date/Time: Sunday 11/09/2016 | 08:00-10:00

Paper Time: 09:44

Venue: Hall H1

First Author: : D.Kang SOUTH KOREA

Co Author(s): :    D. Reinstein   T. Archer   B. Ha   Y. Ji   T. Kim        

Abstract Details

Purpose:

To Compare the clinical outcomes between Low (Less than 140nj) and High Energy small incision lenticule extraction and to correlate with SEM and atomic force morphometric parameters of the extracted human lenticule.

Setting:

Eyereum Eye Clinic, Seoul, Korea London Vision Clinic, UK. Department of Ophthalmology, Severance Hospital, Yonsei University School of Medicine.

Methods:

This prospective consecutive case series included 108 eyes of 54 patients who were randomly assigned to receive either Low energy (<140nj) or High Energy (>140nj) SMILE. Monocular UCVA, constrast sensitivity and corneal aberrations in the early postoperative period were compared. 3 extracted lenticules from each group; were anayzed for morphometric correlation by SEM and atomic force microscopy.

Results:

On POD 1, average snellen UCVA was higher in the LE group (1.0714±0.1436) than the HE group (0.8655±0.1696) (p<0.0001).This difference remained significant upto 1 month after surgery (LE:;1.1385±0.14, HE;1.0171±0.18, p=0.004). Corneal aberrations showed a trend for higher induction of total RMS in the HE group without reaching statistical significance (p=0.062).Surface roughness measured by AFM was significantly higher in each anterior and posterior side of HE than LE (HE, Ra= 0.891±0.171 µm, Rq= 1.024±0.585 µm, Rz= 3.067±0.149 µm; LE, Ra=0.123±0.085 µm, Rq= 0.153±0.102µm, Rz= 0.510±0.311µm; p<0.05). SEM showed that both sides of HE lenticules had more elevated reticular and scale-like surfaces than LE.

Conclusions:

Low energy SMILE showed faster visual recovery in the early postoperative period compared to High energy SMILE. There was a trend for higher total RMS corneal aberrations. This difference may be due to differences in surface roughness of the refractive corneal surfaces as observed by SEM and AFM.

Financial Disclosure:

NONE