Rotational stability and visual outcome after implantation of a new toric intraocular lens for the correction of corneal astigmatism during cataract surgery

Abstract

To evaluate rotational stability and the refractive and visual outcomes of a new aspheric toric intraocular lens (IOL) for correction of preexisting corneal astigmatism during routine cataract surgery. Department of Ophthalmology, Paracelsus Medical University Salzburg, Salzburg, Austria. Case series. Aspheric Bi-Flex T toric IOLs were monolaterally or bilaterally implanted after phacoemulsification in patients with topographic corneal astigmatism between 1.5 diopters (D) and 4.0 D. Preoperative IOL calculations were performed by laser interference biometry (Haigis formula). Appropriate IOL-torus alignment was facilitated by combined imaging and eye-tracking technology. Refraction and uncorrected distance (UDVA) and corrected distance visual acuities were measured 1 day, 1 week, and 1 and 3 months postoperatively. At each visit, photodocumentation in retroillumination was performed to evaluate torus position and potential toric IOL rotation. The mean refractive astigmatism decreased from 1.93 D ± 0.90 (SD) (range 0.5 to 4.0 D) to 0.30 ± 0.54 D (range 0.0 to 1.5 D) at 3 months. Patients achieved a mean UDVA of 0.05 ± 0.12 logMAR (range -0.18 to 0.30 logMAR [∼20/20]). Intraoperative to 3-month postoperative comparison of IOL axis alignment showed low levels of rotation (mean 2.12 ± 3.45 degrees; range -2 to +5 degrees). Implantation of the new aspheric toric IOL was effective, safe, and stable in correcting preexisting regular corneal astigmatism during cataract surgery. Combined imaging and eye tracking seems to be a promising technology to evaluate the correct axis for IOL torus alignment.