Stability of visual outcomes and vector analysis after femtosecond laser-assisted cataract surgery (FLACS) with aspheric toric intraocular lens (IOL)

Session Details

Session Title: Rotational Stability & Outcomes

Session Date/Time: Monday 24/09/2018 | 14:30-16:00

Paper Time: 14:30

Venue: Room A4

First Author: : S.Ti SINGAPORE

Co Author(s): :    S. Chee   Y. Yang                 

Abstract Details

Purpose:

To report the visual results and astigmatic changes by vector analysis following femtosecond laser-assisted cataract surgery (FLACS) with aspheric toric IOL.

Setting:

Singapore National Eye Centre, a tertiary referral public eye care centre.

Methods:

Two-year prospective analysis of FLACS and aspheric toric IOL (cylinder groups 1:<1.0D, 2: 1.0-1.5D, 3: >=1.5D; SN6AT2-T9, Alcon; target plano). IOLs chosen based on Zeiss IOL Master® 700 and Barrett toric calculator. Incisions: ≤2.2mm keratome; Victus™ laser system for capsulotomy and fragmentation. Reference axes were marked manually, intraoperative IOL alignment by degree gauge. Outcome measures (follow-up FU≤ 42days, > 42 days): unaided visual acuity(UVA), mean absolute error (MAE), mean residual refractive cylinder (MRCyl), manifest refraction spherical equivalent (MRSE), astigmatic changes (Alpins iASSORT software; target-induced astigmatism (TIA), surgically-induced astigmatism (SIA), SIA/TIA = correction index(CI), difference vector (DV)/TIA= index of success (IOS)).

Results:

Study involved 170 eyes (mean preoperative cylinder=1.25±0.66D), 67.6% achieved UVA ≤ 20/25. MRCyl = 0.47 ± 0.36D, MAE=0.27±0.19D, MRSE= -0.08±0.3D. MAE was similar in FU ≤42 (0.28±0.23D) & >42 days (0.27±0.21D; p=0.90, independent t-test). SIA =1.28 at 93°; TIA=1.19 at 88°; DV=0.46 at 73°. IOS = 0.45 (0.51, 0.39 & 0.26 in groups 1, 2 & 3 respectively. Mean CI = 1.06; CI analysis, excluding 6 cases ≤ 0.5D (CI 1.67), was no different between FU groups (p>0.05, two-way ANOVA);FU ≤ 42 days: 0.96, 1.14, 1.00 & >42 days:1.08, 1.00, 1.04 for groups 1, 2 & 3 respectively.

Conclusions:

FLACS for astigmatism correction provided effective unaided visual outcomes with stability achieved by 42 days, and no additional benefit for longer FU (p=0.90). Astigmatic vector outcomes were best for patients with > 1.5D astigmatism (IOS=0.26). For extremely low astigmatism (≤0.5D), CI was poor (1.67) possibly due to measurement factors, making toric IOL benefit equivocal, even if indicated with the Barrett toric calculator.

Financial Disclosure:

... receives consulting fees, retainer, or contract payments from a company producing, developing or supplying the product or procedure presented, ... travel has been funded, fully or partially, by a competing company, ... research is funded, fully or partially, by a competing company, ... receives consulting fees, retainer, or contract payments from a competing company