Comparison of Reading Speed after Bilateral Bifocal and Trifocal Intraocular Lens Implantation

Abstract

PurposeTo evaluate and compare visual acuity and reading speed for Korean language between a diffractive bifocal and trifocal intraocular lens (IOL) of the same material and haptic design.MethodsWe reviewed the medical records of the patients who had undergone bilateral cataract surgery with bifocal IOLs (AT LISA 801) on the both eyes (bifocal group) and trifocal IOLs (AT LISA tri 839 MP, trifocal group). The main outcome measures were the uncorrected distance, intermediate, and near visual acuity (uncorrected distance visual acuity [UCDVA], uncorrected intermediate visual acuity [UCIVA], and uncorrected near visual acuity [UCNVA]) and corrected distance, near, and distance-corrected intermediate visual acuity (corrected distance visual acuity [CDVA], corrected near visual acuity [CNVA], and distance-corrected intermediate visual acuity [DCIVA]) at last postoperative follow-up month. Reading speeds for Korean language were measured to check near visual function.ResultsFourteen eyes (7 patients) were included in the bifocal group and 32 eyes of 16 patients in the trifocal group. There were no statistical differences between the two groups with respect to UCDVA, UCNVA, CDVA, and CNVA. However, UCIVA (0.35 vs. 0.22 logarithm of the minimum angle of resolution [logMAR], p < 0.01) and DCIVA (0.34 vs. 0.20 logMAR, p < 0.01) were significantly better in the trifocal group than in the bifocal group. The mean reading speed for logMAR 0.5 optotype (point 10) was 86.50 words per minute (wpm) in the bifocal group and 81.48 wpm in the trifocal group without a significant difference (p = 0.70).ConclusionsTrifocal IOLs provided the same level of distance and near visual acuity and reading speed as that of bifocal IOLs with better intermediate visual acuity.

Comparing the visual outcome, visual quality, and satisfaction among three types of multi-focal intraocular lenses

“…Good near visual acuity does not always indicate good functional near vision, which is necessary for reading books or newspapers. Therefore, recent studies have used a reading speed test, which reflects functional near vision, to determine the clinical outcome of multifocal IOLs 13,14 .…”

“…One study that compared the reading speeds of patients with a bifocal IOL (AT Lisa,) to those of patients with Trifocal IOL(AT Lisa Tri)found no significant difference between the two groups 14 . Another study reported no difference in reading speed between patients with a bifocal IOL (ReSTOR) and those with the Symfony IOL 13 .…”

“…However, for very small font sizes, the Mix-and-Match group had faster reading speeds than did the other groups. It is possible that differences in the testing method and language characteristics contribute to variation in the results 14,15 .…”

“…The reading speed was measured 3 months after surgery at a distance of 50 cm using an iPad application (iPad Retina Display; Apple Inc., Cupertino, CA) 14 . The print size used on the reading chart ranged from 1.0 to 0 logarithm of the minimal angle of resolution (log MAR).…”

Comparison of Postoperative Visual Performance Between Bifocal and Trifocal Intraocular Lens Based on Randomized Controlled Trails: A Meta-Analysis

“…For the AT LISA subgroup, UIVA and DCIVA were significantly better in the trifocal IOLs (AT LISA tri 839M). Many researches have confirmed better intermediate visual performance of AT LISA tri 839M trifocal IOLs than the AT LISA bifocal IOLS in both clinical study and the optical bench[22][23][24][25], which prove that the AT LISA tri 839M can provide a third effective focus. Additionally, no difference was found for the UIVA and DCIVA between the bifocal (Re STOR bifocal IOLs) and the trifocal IOLs(Fine Vision trifocal IOLs) in another subgroup.…”