Assessment of dysphotopsia in pseudophakic subjects with multifocal intraocular lenses

Abstract

AimTo better understand the phenomenon of dysphotopsia in patients implanted with multifocal intraocular lenses (IOLs).MethodsForty-five patients (aged 61.8±8.9 years) implanted bilaterally with Tecnis ZM900 (diffractive multifocal), Lentis Mplus MF30 (segmented refractive multifocal) or Softec-1 (monofocal) IOLs (each n=15) 4–6 months previously and who had achieved a good surgical outcome were examined. Each reported their dysphotopsia symptoms subjectively, identified its form (EyeVisPod illustrations), quantified retinal straylight (C-Quant) and halo perception (Aston halometer). Retinal straylight and halometry was repeated by a second masked clinician to determine interobserver repeatability.ResultsSubjective dysphotopsia ratings were able to differentiate Tecnis ZM900 from Lentis Mplus MF30 (p<0.001), but not Lentis Mplus MF30 from groups implanted with Softec-1 (p=0.290). Straylight was similar between the monofocal and multifocal IOL designs (p=0.664). ZM900 IOLs demonstrated a uniform increase in dysphotopsia in comparison with the monofocal IOL (p<0.001) as measured with the halometer, whereas sectorial refractive multifocal IOLs demonstrated a localised increase in dysphotopsia over the inferior visual field. Intraobserver repeatability was good for the straylight (intraclass correlation coefficients (ICC)=0.77) and halometry (ICC=0.89). There was no significant correlation between the subjective dysphotopsia severity and the straylight (p=0.503) or halometry (p>0.10) quantification or between straylight and the halo area (p>0.30).ConclusionsMultifocal IOLs induce symptoms of dysphotopsia. Straylight did not differentiate between IOL designs, however halometry identified clear differences in light scatter due to the IOL optics. Whereas, subjective rating of overall dysphotopsia are not strongly associated with straylight or halo perception, the halometry polar diagram reflected the subjective descriptions of dysphotopsia.

The effects of light scatter when using a photochromic vs. non-photochromic contact lens

“…Various forms of halometric testing have been published 16 , 17 , 18 , 19 and the method has been shown to be highly reliable. 20 Prior to testing, subjects were given a visual guide that provided examples of what halos and starbursts commonly look like to normal viewers in natural scenes (e.g., car headlights, streetlights, against a blue sky or created through stadium lights, e.g., see Fig. 1 ).…”

Presbyopia: Effectiveness of correction strategies

“…have been to be repeatable and discriminatory between different optical designs to correct presbyopia (Buckhurst et al, 2017).…”

Randomized Crossover Trial of Silicone Hydrogel Presbyopic Contact Lenses

“…Halometry was used to quantify the radial glare in eight meridians around a light source. 30 Finally, slitlamp biomicroscopy was performed after lens removal to evaluate bulbar, limbal, and palpebral hyperemia (with lid eversion) and the corneal staining (with fluorescein observed with blue light through a yellow filter), graded using the Efron grading scale in 0.5 steps.…”