Incidence and factors for pseudoaccommodation after monofocal lens implantation: the Monofocal Extended Range of Vision study

Abstract

Purpose: To screen patients with a monofocal intraocular lens (IOL) for incidence of unaided 20/40 and 0.3 LogMAR for distance and near (pseudoaccommodation) and to find factors for pseudoaccommodation. Settings: University Hospitals Sussex NHS Foundation Trust, Brighton, United Kingdom. Design: Prospective study. Methods: This was a single-eye study (ClinicalTrials.gov: NCT04011696). At 3 to 9 months, refraction, uncorrected and corrected distance and uncorrected near visual acuity (logMAR), spherical equivalent (SEQ), mesopic pupil size (PS), total eye spherical (Z4 0), vertical coma (Z3 −1) aberrations, reading speed and smallest print size were assessed. Refractive astigmatism (RA) was classified as against-the-rule, with-the-rule, oblique and no astigmatism. Data on preoperative axial length (AL) and anterior chamber depth (ACD) were collected. Results: 29 patients (9.6%, 95% CI, 6.5-13.5) had pseudoaccommodation. In cases vs controls, median SEQ, PS, total Z4 0, Z3 −1, reading speed, smallest print size, preoperative ACD, preoperative AL were: −0.39 vs 0.0 diopters; 3.62 vs 4.10 mm; 0.01 vs 0.02 μm; 0.018 vs 0.022 μm; 106 vs 133 words per minute; 0.30 vs 0.50 logMAR; 2.94 vs 3.13 mm, 23.4 vs 23.7 mm, respectively. RA was not different between the groups. Univariate analysis revealed preoperative ACD (odds ratio [OR], 0.38, 95% CI, 0.16-0.94, P = .04), SEQ (OR, 0.61, 95% CI, 0.42-0.88, P = .01), total Z4 0 (OR, 0.0003, 95% CI, 0.00-0.39, P = .03) and PS (OR, 0.39, 95% CI, 0.22-0.69, P < .041) to be significant. Whereas multivariable logistic regression identified: preoperative AL (OR, 0.62, 95% CI, 0.42-0.91, P = .02), SEQ (OR, 0.49, 95% CI, 0.31-0.78, P = .01), Z4 0 (OR, 0.00, 95% CI, 0.0-0.01, P = .01) and PS (OR, 0.41, 95% CI, 0.23-0.75, P = .01) to be significant. Conclusions: A combination of low myopic SEQ, lower Z4 0, shorter preoperative AL, and smaller PS increases the chances of pseudoaccommodation.