PURPOSE:To compare disk halo size in response to a glare source in eyes implanted with an aspheric apodized diffractive multifocal intraocular lens (IOL) or aspheric monofocal IOL.SETTING: Rementeria Ophthalmological Clinic, Madrid, Spain.DESIGN: Prospective randomized masked study. METHOD:Halo radius was measured using a vision monitor (MonCv3) with low-luminance optotypes in 39 eyes that had cataract surgery and the bilateral implant of an Acrysof Restor SN6AD1 multifocal IOL or Acrysof IQ monofocal IOL 6 to 9 months previously. The visual angle subtended by the disk halo radius was calculated in minutes of arc (arcmin). Patient complaints of halo disturbances were recorded. Monocular uncorrected distance visual acutity (UDVA) and corrected distance visual acuity (CDVA) were measured using high-contrast (96%) and lowcontrast (10%) logMAR letter charts. RESULTS:The study comprised 39 eyes of 39 subjects (aged 70 to 80 years); 21 eyes had a multifocal IOL and 18 eyes a monofocal IOL. Mean halo radius was 35 arcmin larger in the multifocal IOL group than the monofocal group (P < .05). Greater halo effects (P < .05) were reported in the multifocal IOL group. Mean monocular high-contrast UDVA and low-contrast UDVA did not vary significantly between groups, whereas mean monocular high-contrast CDVA and low-contrast CDVA were significantly worse at 0.12 and 0.13 logMAR (P < .01) in the multifocal than in the monofocal IOL group, respectively. A significant positive correlation (r Z 0.72, P < .001) was detected by multiple linear regression between the halo radius and low-contrast UDVA in the multifocal IOL group. CONCLUSIONS:The diffractive multifocal IOL gave rise to a larger disk halo size, which was correlated with a worse low-contrast UDVA. The authors have no commercial or proprietary interests in the devices used in this study or manufacturing companies. J Cataract Refract Surg 2015; -:---Q 2015 ASCRS and ESCRSCurrent diffractive multifocal intraocular lenses (IOLs) provide satisfactory distance, intermediate, and near visual acuity, reducing spectacle dependency.1 However, adverse subjective visual phenomena, such as glare and halos, are often reported by patients with multifocal IOLs, especially when driving at night. 1Theoretical optical design predictions suggest that multifocal IOLs will induce more light scatter than monofocal IOLs.2 In a refractive-diffraction IOL designed to simultaneously yield focused images of near and far objects, 3 forward scattered light from a glare source forms a veil of luminance over the retina.Disk halos form because the out-of-focus image has a larger diameter than the sharp image on the retina. 4 The unwanted effect of the light in the out-of-focus image may be visually disturbing, depending on 2 factors: the distance along the optical axis between these 2 images (the greater the distance between the 2 separate focal points along the optical axis, the greater will be the diffusion or blur circle surrounding the primary focus), and their relative energy distribution (the ene...

Purpose To determine the size of a halo in the visual field induced by bright light after cataract surgery and implantation of an aspheric apodized diffractive multifocal intraocular lens (IOL) or aspheric monofocal IOL. Methods This prospective observational study comprised 54 healthy eyes (mean age 72.6 ± 10.4) of 54 subjects having cataract surgery with bilateral implantation of an AcrySof ReSTOR SN6AD1 IOL (32 eyes, multifocal group) or AcrySof SN60WF IOL (22 eyes, monofocal group). Six months postoperatively, halo size was measured using the Vision monitor. Optotypes of low luminance (5cd/m2) were presented at a distance of 2.5 m. The visual angle subtended by the radius of the halo was calculated in minutes of arc (arc min). Best‐corrected distance logMAR visual acuity (VA) was evaluated with high‐contrast (HC‐96%) and low‐contrast (LC‐10%) logMAR Bailey‐Lovie letter charts. Results The mean radius of the halo was 219.3 ± 42.1 and 194.0 ± 55.3 arc min (p > 0.05) in the multifocal and the monofocal groups respectively. The HC and LC VA means showed significant differences between the two groups, being worse in the multifocal group. Also, the HC and LC‐VA exhibited a significant correlation with halo size (r= 0.52 y r= 0.57 respectively). Conclusion Mean halo size was not significantly different between the multifocal ReSTOR SN6AD1 and the monofocal AcrySof SN60WF IOLs. Worse HC and LC‐VA values were related to higher halo size measurements in the IOLs groups.