Astigmatism-Correction And Visual Outcomes With The Liberty 677Mty Trifocal Toric Intraocular Lens – A One-Year Follow-Up

to evaluate the efficiency of the trifocal Liberty 677MTY intraocular lens (IOL; Medicontur Medical Engineering Ltd) in correcting preoperative corneal astigmatism in cataract patients demanding for spectacle independence. Visual and refractive performance of the lens, as well as visual quality and visual functions were assessed during the first postoperative year.

Department of Ophthalmology, Institute of Aviation Medicine Prague, Czech Republic

The retrospective evaluation included 26 eyes of 14 patients with a preoperative corneal astigmatism of at least 1.0 Diopters (D). All patients were followed up for one year after the mono- or binocular implantation of the investigated IOL. Residual refractive errors (spherical equivalent refraction: SEQ; astigmatism: Cyl) and uncorrected and corrected visual acuities at multiple distances were measured. Binocular visual acuity and contrast sensitivity defocus curves were plotted. Visual functions and patient satisfaction were assessed using a questionnaire completed by each patient. The efficiency of astigmatism-correction was determined by using the vector analysis method.

The mean SEQ improved from 2.72 ± 1.62 D to 0.10 ± 0.48 D, while the cylindric refraction decreased from 1.18 ± 0.45 D to 0.16 ± 0.31 D. Vector analysis proved efficient astigmatism correction with a centroid of 0.10 ± 0.34 D at 161°. Ninety-two % of eyes resulted within 0.5 D from the target refraction, emmetropia. All eyes were within 1.0 D. An uncorrected distance visual acuity of at least 20/20 was achieved by 85% of eyes, and 69.2% had an unaided near vision of at least 20/25. Defocus curves were stable during the one-year follow-up. Visual acuities were 0.1 logMAR or better from +1.0 to -3.5 D defocus values. Visual tasks could be performed without, or only with minor difficulties. Our patients were highly satisfied with the outcomes.

The toric model of the investigated presbyopia-correcting IOL was found to be efficient in vision correction of cataract patients with corneal astigmatism. Refractive and visual outcomes are predictable and provide excellent vision correction. Visual acuity and contrast sensitivity defocus curves confirm favorable visual quality across the entire defocus range. The objective measurements are supported by the visual function assessment and high satisfaction rate of our patients. According to our results, we believe that the Liberty Toric IOL is an efficient product to correct astigmatism and presbyopia in cataract patients. Visual outcomes are maintained during the first postoperative year; visual comfort can be provided in the long-term.