Posters

Refractive and visual outcomes after FS-SBK for myopia with thin corneas

Poster Details

First Author: I. Remesnikov KAZAKHSTAN

Co Author(s):    V. Kim              

Abstract Details

Purpose:

To analyze the refractive and visual outcomes after femtosecond sub-Bowman's Keratomileusis (FS-SBK) procedure for myopia with thin corneas.

Setting:

'ASTANA VISION', Astana, Kazakhstan.

Methods:

A retrospective noncomparative study of 118 consecutive cases of FS-SBK of 60 patients with myopia with central corneal thickness of 500 microns or less was performed. The group consisted of 24 males (40%) and 36 females (60%), the average age was 27 years (range 18 to 42 years). All patients received a standard ophthalmologic examination. Pachimetric measurements of central corneal thickness before surgery were made by Allegro Oculyzer (Pentacam II (Oculus) and mean value was 489.6 ± 9.06 µm (from 462 to 500 µm). Mean MRSE before surgery was -6.05 ± 2.00 D (from -0.75 D to -11.625 D) with astigmatism up to 8.0 D (mean -1.77 ± 1.65 D). Mean preoperative BSCDVA was 0.74 (0.132 logMAR), while only 72% of eyes had a BSCDVA 0.6 or better (≤ 0.2 logMAR) and in any case not fixed BSCDVA over 1.0 (<0.00 logMAR). Alcon's WaveLight Refractive Suite of excimer laser Allegretto Wave Eye-Q Blue Line 400 Hz and femtosecond laser FS-200 was used. Intended thickness of corneal flap was equal to 90 microns, the target Post Op refraction planned as emmetropia. Post Op follow-up for at least 6 months after surgery was performed.

Results:

At 1 day and 6 months Post Op NCDVA was 0.87 (0.065 logMAR) and 0.95 (0.02 logMAR), respectively. At 6 months Post Op follow-up the index of efficiency (BCDVA Pre Op vs. NCDVA Post Op) was 97% due by loss of 1 line of NCDVA in 3 cases and 2 lines in 1 case. In 87% (74 eyes) after the FS-SBK procedure a NCDVA reached 0.6 or better (≤ 0.2 logMAR) and 12% (12 eyes) achieved NCDVA 1.2 (-0.1 logMAR). Safety index (BCDVA Pre Op vs. BCDVA Post Op) was 98%, due 2 cases of lost of 1 line BCDVA. Achieved predictability index equal to 97%, as there were 4 cases of postoperative refraction deviation from the target by more than ± 0.5 D and only one case of deviations of more than ± 1.0 D with no overcorrected cases.

Conclusions:

Received high refractive and visual results of FS-SBK procedure in the correction of myopia with thin corneas. FINANCIAL INTEREST: NONE