Evaluation Of Fixation Stability And Retinal Sensitivity Assessment By Microperimetry In Patients With Multifocal And Monofocal Intraocular Lenses Implanted

While there is evidence suggesting that microperimetry may aid in intraocular lens (IOL) selection, studies comparing fixation stability and retinal sensitivity between patients with multifocal IOLs and monofocal IOLs remain limited. Understanding the relationship between microperimetric findings and IOL type may contribute to better patient selection and improved postoperative outcomes.

In this study, we aimed to evaluate fixation stability and retinal sensitivity using microperimetry in patients who underwent cataract surgery with either trifocal or monofocal IOL implantation. 

This study was conducted at Bezmialem Vakif University, Department of Ophthalmology, Istanbul, Turkey.

Patients who underwent uneventful cataract surgery with either monofocal or trifocal IOL implantation were included. Preoperative and postoperative evaluations included BCVA, intraocular pressure, corneal topography, macular OCT, and microperimetry using the MP-1 microperimeter (Nidek, Japan). Retinal sensitivity was measured at 2°, 6°, and 10°, while fixation stability was assessed using the Bivariate Contour Ellipse Area (BCEA) method. Fixation points within 2° and 4° were recorded. Contrast sensitivity was evaluated with the Pelli-Robson chart. All measurements were performed six months postoperatively under mesopic conditions to minimize external light interference.

The study included 38 patients with trifocal IOLs and 44 with monofocal IOLs. BCVA was significantly better in the monofocal group (0.01 ± 0.02 vs. 0.02 ± 0.03, p = 0.008). Contrast sensitivity was higher in monofocal IOLs (1.80 ± 0.10 vs. 1.70 ± 0.11, p < 0.01). Retinal sensitivity was significantly higher in monofocal IOLs at 10° (p = 0.039). Fixation stability (BCEA) was superior in monofocal IOLs (p = 0.025). Fixation location and FN-4° values were similar between groups (p > 0.05), but FN-2° was significantly higher in monofocal IOLs (p = 0.012).

Trifocal IOLs resulted in decreased BCVA, contrast sensitivity, and retinal sensitivity compared to monofocal IOLs. Fixation stability was also lower in the trifocal group, suggesting a potential impact on visual function. These findings indicate that patients should be informed about possible visual function differences before surgery. Larger, multicenter studies are needed to confirm these results and further investigate the long-term implications of trifocal IOL implantation.