Visual outcomes after progressive apodized diffractive intraocular lens implantation

To assess photopic and mesopic vision in patients implanted with the Bi-Flex® M 677 MY bifocal intraocular lens (IOL).

In this prospective clinical study, 25 patients with cataract in both eyes were subjected to cataract surgery and bilateral implantation of the Bi-Flex® M 677MY (Medicontur, Hungary) IOL. Three months after surgery, high-contrast photopic uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA) were determined. Intermediate at 65 cm (DCIVA) and near at 40 cm (DCNVA) visual acuity were also measured, both with best distance correction. The CSV-1000 test chart was used to assess contrast sensitivity (CS). Defocus curves were constructed under photopic and mesopic conditions, determining binocular best-corrected visual acuity over the range +1.50 D to -4.00 D in 0.50-D steps. A KR-1W Wavefront Analyzer was used to measure pupil size and aberrometric outcomes. Presence and type of dysphotopsia were evaluated with the Likert scale.

Mesopic mean pupil diameter was 4.58 ± 0.73 mm. The mean values at 3 months were UDVA 0.03 ± 0.09, CDVA -0.05 ± 0.06, DCIVA 0.20 ± 0.07, and DCNVA 0.11 ± 0.08. Mean CS for the 4 frequencies examined were 1.66 ± 0.16, 1.75 ± 0.14, 1.39 ± 0.22, and 0.96 ± 0.19. Significant differences were observed in defocus curves for photopic and mesopic conditions. A significant correlation between pupil diameter and the dysphotopic photopic was found (r = 0.62; p = 0.02).

The evaluated progressive apodized diffractive design IOL provides effective restoration of visual function in far and near vision distance with an adequate intermediate visual quality between -1.00 and -1.50 focus.