Posters

Effects of femtosecond lenticule edge ladder design on visual acuity outcome

Poster Details

First Author: J.Bai CHINA

Co Author(s):    T. Zhang   Q. Kan           

Abstract Details

Purpose:

To analyze the effect of 'no trimming' design in the optical ablation zone on postoperative visual quality in patients, who have underwent the femtosecond lenticule extraction surgery, especially in dilated pupils

Setting:

Department of Ophthalmology, Institute of Field Surgery, Daping Hospital, Third Military Medical University, Chongqing, China

Methods:

Prospective cohort study. In patients with a total of 104 cases (208 eyes)，including thin flap LASIK group 38 cases (76 eyes), femtosecond LASIK 28 cases (56 eyes) and Femtosecondsmall incision lenticule extraction （SMILE）surgery group 38 cases (76 eyes). Thin flap LASIK group applied excimer laser cutting equipment, optical zone is 6.0 mm, transition zone is 1.25 mm; femtosecond LASIK group used femtosecond laser for corneal flap, optical zoom is 6.0 mm, transition zone is 1.25 mm; SMILE group used femtosecond laser for refractive lenticule (6.0 mm)extraction . Post-operative assessments included uncorrected visual acuity, contrast sensitivity (CS), glare sensitivity (GS) and wavefront aberration test in normal（≤5mm） and dilated（≥7mm） pupils. Using SPSS 15.0 statistical software, quantitative data normality test, in line with the normal distribution using the ± s, using one-way ANOVA, after multiple group comparison, there were differences between the groups were using LSD (t test) continue pairwise comparison. All test results were considered statistically significant while P<0.05

Results:

No serious intraoperative and postoperative complications were found in the three groups, and postoperative UCVA are reaching or higher than preoperative best corrected visual acuity of preoperative refractive status. In normal pupils (5 mm or less) state, visual contrast sensitivity with no glare stimulation or glare stimulation among the three groups was no significantly statistical difference. Also In dilated pupils (7 mm or higher), no significantly statistical difference was found between no glare stimulation and glare stimulation. No statistical difference of waveform aberration C12 spherical was found in normal pupils state among the three groups (F = 2.020, P>0.05).Whereas in dilated pupils, no statistically significant difference between thin femtosecond LASIK and flap LASIK group (t = 0.358P = 0.723). Compared with SMILE group there were significant differences in thin flap LASIK group, femtosecond LASIK group (t=2.942，P=0.009；t=3.264，P=0.003). And the C12 values of Smile group（0.422±0.123）is smaller than the thin flap LASIK group （0.577 ±0.147）and femtosecond LASIK group（0.606±0.158）under both pupil states.

Conclusions:

Compared with 'trim' thin flap LASIK and femtosecond LASIK that both set a transition zone, all femtosecond lenticule extraction surgery without optical ablation zone trimming design had no obvious effect on postoperative visual quality. FINANCIAL INTEREST: NONE