Ocular aberrations and visual quality after aspheric toric intraocular lens implantation: comparative study

Session Details

Session Title: Interactive Free Paper Session: Pseudophakic IOLs/ Toric

Session Date/Time: Monday 15/09/2014 | 16:30-18:30

Paper Time: 17:40

Venue: Capital Hall B

First Author: : A.Assaf EGYPT

Co Author(s): :    A. Hashem   E. Samir   A. Abodarahim   A. Anbari     

Abstract Details

Purpose:

To assess the efficacy of astigmatic correction of Tecnis toric intra-ocular lens (IOL) during cataract surgery, and to evaluate the impact of aspheric-toric optics on ocular higher order aberration and visual quality.

Setting:

Ain Shams University and Al-Watany Eye Hospital

Methods:

Included in this comparative study eyes with senile cataract and regular corneal astigmatism from 1 to 3 diopters (D). Two groups were identified, one group included eyes of patients who were interested in astigmatism correction during cataract surgery, this group assigned for Tecnis toric IOL (Tecnis-T group). The other group included patients who did not mind to have postoperative spectacles for distance and received Tecnis ZCB00 IOL (Tecnis-1 group). Both lenses share the same platform, material and and manufacturer (Abbott Medical Optics). Study parameters included postoperative residual refractive astigmatism, ocular higher order aberration (spherical aberration (SA), coma, trefoil) and visual quality (modulation transfer function (MTF) and Strehl ratio). All measurements were performed objectively by optical path difference scanning system (OPD scan III, NIDEK Co Ltd). Examination was scheduled  at 1 and 3 months postoperatively. Exclusion criteria included eyes with irregular corneal astigmatism, corneal opacities  and intra operative complications.

Results:

All surgeries went uneventfully. Tecnis-T and Tecnis-1 groups comprised  46 and 60 eyes respectively. Residual refractive astigmatism was significantly lower in Tecnis-T group. Total spherical aberration was  -0.06±0.11μ in Tecnis-T group, and -0.09 ±0.2μ in Tecnis-1. Total ocular coma and trefoil were higher in Tecnis-T but without statistical significant difference compared to Tecnis-1 group. Average Strehl ratio was 0.113 and 0.059 in Tecnis-T and Tecnis-1 groups respectively (p<0.05). MTF was significantly better Tecnis-T group. Mean photopic and mesopic pupil diameters were similar in both groups.

Conclusions:

Toric IOL with an aspheric optic is effective for astigmatism correction during cataract surgery. Aspheric and toric components have no significant impact on postoperative coma and trefoil. Low postoperative higher order aberration of the eye result in a decent visual quality evidenced by MTF and Strehl ratio.

Financial Interest:

NONE