Bioptic To Treat High Refractive Errors

Published 2022 - 40th Congress of the ESCRS

Reference: PO504 | Type: ESCRS 2022 - Posters | DOI: 10.82333/319f-kp47

Authors: Sami mahmoud Alrabiah* ¹

¹Rabiah Medical Center,kuwait,Kuwait

Purpose

To evaluate the refractive surgery outcome for patients who had relative corneal thickness insufficiency to correct a relative high refractive error, using the Bioptic technique

To treat patients with either relative thinner cornea than needed or higher refrctive error than given stromal thickness, we either

A-Full correction with reducing Treatment and Transitional zones, with subsquent increase incidence of Spherical Aberration

B-Full correction with reducing residual cornal thickness, with subsquent increase incidence of Ectasia C- Consider Phakic IOL if AC depth and white to white allows D- Bioptic treatment

Setting

At Rabiah Medical Center, Ophthalmolgy Department,

NIDEK, Quest, EC-5000, ablation zone 5mm, transition zone 9mm, 17-21micron tissue ablation per diopter myopic correction

Ziemer Femtosecond LDV laser, 110 microns flap thickness

all cases had wavefront guided treatment

flap thickness + treatment ablation depth = < 40% of original corneal thickness

Methods

Bioptic treatment

this study includes 22 patients 14 female, 8 male had refractive error ranging from -7.50 -9.50 diopters, corneal thickness ranging from 505- 542 microns,

1- first step is femtolasik treatment to correct as mush as possible without jebrodising safty and quality 2- Second step after 6 months , Transepithelial PRK

All tests such as topography, tomography, spherical aberration, Qvalue, pachymetry, refraction, were within normal readings and were repeated after the first and second treatment as well as wave front study for induced errors,

Results

Average refractive error was -8.18 diopters, average Q value was -0.1, average SA 0.35

First post operative values were

Average refractive error was -1.50 diopters, average Q value was 0.49 , average SA 0.66

Second post operative values were

Average refractive error was -0.03 diopters, average Q value was 0.06 , average SA 0.23

Compared to lower refractive error correction ( one stage femtolasik)

Average refractive error was -0.1 diopters, average Q value was 0.06 , average SA 0.35

Conclusions

Bioptic technique, is not only a method to correct the total refractive power on two stages ,but safety is kept in mind as second stage is on the flap which has no influence over corneal stability and power so no harmful effect regarding the stromal thickness but also it reduces all wave front errors induced by Lasik, and give us much better quality of vision that is better than single treatment for lower degrees