Examining visual outcomes of bilateral trifocal IOL

A new trifocal diffractive IOL (FineVision trifocal IOL, PhysIOL), implanted bilaterally, achieved a full range of adequate vision, satisfactory contrast sensitivity, and a lack of significant adverse photic phenomena, according to Spanish researchers reporting in BMC Ophthalmology.

In a prospective, nonrandomized, observational study, 44 eyes of 22 patients were assessed before and three months after cataract surgery and IOL implantation. A Topcon KR-1 W wavefront analyser was used to determine aberrations, and LogMAR visual acuity was measured at distance, intermediate, and near. Contrast sensitivity was estimated using the Pelli-Robson letter chart and the CSV-1000 test. Both photopic and mesopic defocus curve testing was performed, and the Halo v1.0 program was used to assess adverse photic phenomena.

The findings:

• Mesopic pupil diameter mean aberration values were: total HOA RMS 0.41 ± 0.30 μm; coma 0.32 ± 0.22 μm; spherical aberration 0.21 ± 0.20 μm. 

• Binocular logMAR measurements were −0.05 ± 0.05 for corrected distance visual acuity, 0.15 ± 0.10 for distance corrected intermediate visual acuity, and 0.06 ± 0.10 for distance corrected near visual acuity.

• Mean Pelli-Robson contrast sensitivity was 1.40 ± 0.14 log units.

• CSV-1000 contrast sensitivity was 1.64 ± 0.14 log units at 3 cycles per degree (cpd), 1.77 ± 0.18 log units at 6 cpd, 1.44 ± 0.24 log units at cpd, and 0.98 ± 0.24 log units at 18 cpd.

• Significant differences were observed in the photopic and mesopic defocus curves.

• The mean disturbance index was 0.28 ± 0.22.

“Distance visual outcomes of the trifocal IOL FineVision were similar to those of monofocal IOLs, while near visual outcomes resembled those of bifocal diffractive IOLs,” the researchers wrote. “In addition, a real improvement in intermediate vision was noted, which was not associated with impairment of far or near vision. Trifocality did not lead to increased subjective visual discomfort in comparison to bifocality. Moreover, the indications and limitations of the FineVision lens do not differ from those of other diffractive lenses.”