Rotational stability of a single-piece toric acrylic intraocular lens

To assess the rotational stability of a single-piece toric hydrophobic acrylic intraocular lens (IOL) during the first 6 postoperative months.

Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom.

Prospective case series.

Eyes with age-related cataract and corneal astigmatism (1.00 to 3.00 D diopter [D]) were measured by partial coherence interferometry (IOLMaster). Preoperatively, the horizontal axis was marked. Surgical technique included a standardized temporal clear corneal incision, phacoemulsification, and in-the-bag implantation of a toric IOL (AcrySof SN60TT). Rotational stability of the IOL was assessed using retroillumination photographs postoperatively at 1 hour and at 1 and 6 months. Uncorrected (UDVA) and corrected distance visual acuities, residual refractive error, and keratometric and refractive cylinders were measured.

The study enrolled 30 eyes (30 patients). The mean absolute IOL rotation was 2.44 degrees ± 1.84 (SD) at 1 month and 2.66 ± 1.99 degrees at 6 months. The photographic technique had high reproducibility of axis measurement, with consecutive measurements varying by less than 2.0 degrees. The mean UDVA was 0.16 logMAR (range 0.42 to -0.18 logMAR) at 1 month and 0.20 logMAR (range 0.60 to -0.20 logMAR) at 6 months. The residual refractive cylinder by autorefraction was -0.84 D (range -2.00 to 0.00 D) and -0.80 D (range -1.75 to 0.00 D), respectively.

The acrylic toric IOL was rotationally stable within the first 6 months postoperatively. The photographic and axis analysis method to evaluate stability had high reproducibility and detected small changes in rotation.