Abstract
Purpose :
To investigate the effect of pupil size and contraction on near vision performance in eyes treated with monovision or a diffractive apodized multifocal intraocular lens (mfIOL).
Methods :
33 patients (66 eyes) with formal indication for cataract surgery were included and randomly assigned to bilateral implant of ReSTOR SN6AD1 apodized diffractive multifocal IOL (Alcon Laboratories, Inc.) (mfIOL, n = 32 eyes); or monovision with SN60WF for emetropia on dominant eye (WF-F; n = 17 eyes) and -1.25 D on the other eye (WF-N, n = 17 eyes). Comprehensive ophthalmological examination including far and near best-corrected, and without correction, visual acuity (VA) were performed at baseline and one year after surgery. Defocus curve was evaluated one year after surgery to determine the area-under-the-curve (d-AUC) as an index of near, intermediate and far visual recovery. Dynamic pupillary diameter was recorded using an automatic pupilometer (ISCAN - AA-ETL-100H; ISCAN, Inc. Woburn, MA) under dimer background (1 cd/m2 – ColorDome; Diagnosys LLC) and during a 200 ms flash of 30 cd/m2.
Results :
There was no significant difference between groups for far or near VA, 48 weeks after surgery. Mean ± SE near VA (logMAR) was mfIOL: 0.06±0.01 and WF-N: 0.10±0.02 (p>0.05); and far VA was mfIOL: 0.09 ± 0.03 and WF-F: 0.11 ± 0.03. As expected, defocus curves for mfIOL showed a 2-peek pattern, with d-AUC of 2.0 ± 1.3 logMAR.dpt, while for monovision, a single peek was found, with d-AUC of 4.67 ± 1.51 logMAR.dpt. No correlation was found between pupil size measured before the light stimulation or the amplitude of pupil contraction and near or far VA or d-AUC, but interestingly, pupil size during light exposure was significantly correlated with d-AUC (r=0.54; p=0.0117).
Conclusions :
Eyes implanted with the SN6AD1 mfIOL or monovision achieve similar near and far visual acuity. These data indicate that the calculated area under the defocus curve might be an objective index to report near, intermediate and far visual acuity recovery, and found that this index can be associated with photopic pupil size.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.