JCRS Volume 46 Issue 5
Trifocal comparison
Trifocal intraocular lenses (IOLs) are now being implanted in cataract patients as well as those with presbyopia. A new randomized, prospective study compared 2 diffractive trifocal toric IOLS. 60 patients were randomised to receive bilateral implantation of either the FineVision Pod FT toric IOL (PhysIOL) or the AcrySof IQ PanOptix toric IOL (Alcon). At three months the study found no significant differences in uncorrected and corrected distance and near visual outcomes between the groups. Contrast sensitivity, quality of vision scores, and the level of spectacle independence were similar in both groups. Levels of IOL axis misalignment and magnitude of error of astigmatic correction were also similar. The incidence of photic phenomena was low for both lens types. The study did find significantly better values of uncorrected intermediate visual acuity and distance corrected intermediate visual acuity in favour of the PanoOptix lens.
FJ Ribeiro et al., “Comparison of visual and refractive outcomes of 2 trifocal intraocular lenses”, 46(5):694-699.
Ange kappa and trifocal IOLs
Does a large angle κ contribute to decentration and poor outcomes in multifocal IOL patients? Researchers evaluated 63 eyes of 63 patients that had bilateral implantation of a diffractive trifocal IOL (POD F, PhysIOL). Pupil offset was used to estimate of angle κ using the Pentacam (Oculus) preoperatively and at 3 months postoperatively. There was a significant decrease in pupil offset values postoperatively. The study showed no statistically significant difference in any of the refractive and visual acuity outcomes between eyes with small pupil offsets and eyes with large pupil offsets. All but one IOL were perfectly centred. The majority of patients (14 of 16) complaining of significant halos had eyes with small pupil offsets. The researchers hypothesize that the tolerance to larger pupil offset might be due to the IOL optical design, with the first diffractive ring being larger than other commonly used multifocal IOLs.
N Garzón et al., “Influence of angle κ on visual and refractive outcomes after implantation of a diffractive trifocal intraocular lens”, 46(5):721-727.
Collamer lens sizing with SS OCT
Anterior segment swept source ocular coherence tomography appears to provide reliable sizing information for patients being considered for collamer lens implantation. Investigators obtained pre-operative OCT scans for 81 eyes of 41 patients and used NK-formula version 2 (NK-formula V2) data to calculate lens size. Three-month follow-up results indicated that optimization approach has an ‘excellent ability’ to select an appropriate ICL to be implanted regardless of the value of other ocular parameters and age, other than anterior chamber width. A majority, 91.2%, achieved a moderate degree of vaulting.
T Nakamura et al., “Optimization of implantable collamer lens sizing based on swept-source anterior segment optical coherence tomography”, 46(5):742-748.
