Abstract
Purpose: :
Decentration of multifocal contact lenses has been shown to induce significant optical aberrations. Intraocular lenses (IOLs) exhibit prism and coma when decentered or tilted. Since the center of the capsular bag is along the optical axis of the eye and the pupil is usually nasal by about 3 to 5 degrees (angle Kappa), an IOL centered in-the-bag is usually temporal to the pupil. The anatomical pupillary axis of the eye, visual axis, and optical axis are not aligned. When the rings of a multifocal IOL are not concentric with the patient’s pupil, the refractive or diffractive pattern becomes asymmetric and patients may complain of reduced quality of vision of daytime images and asymmetric halos around lights at night. The purpose of this study was to investigate the improvement in objective and subjective quality of vision following argon laser iridoplasty to center the pupil over a multifocal IOL in symptomatic patients.
Methods: :
A retrospective chart review was undertaken of fourteen eyes of 11 patients who had undergone argon laser iridoplasty to center the pupil over a multifocal IOL. All eyes had previously undergone uncomplicated cataract surgery at least 3 months prior to argon laser iridoplasty. Argon laser iridoplasty was performed after all contributing factors for glare and halo were treated (e.g. residual refractive error, ocular surface disease, posterior capsule opacities, and cystoid macular edema). UCVA, BCVA, contrast sensitivity, and patient satisfaction were measured prior to argon laser iridoplasty and one month following argon laser iridoplasty. Argon laser iridoplasty spots were placed in the iris mid-periphery with the following parameters: 500 milliwatt energy, 500 micron diameter, 500 millisecond diameter.
Results: :
Mean BCVA improved from 20/32 to 20/24(p<.05) and mean UCVA improved from 20/40 to 20/31 (p<.05). Subjective quality of vision improved from 3.0-7.9 (p<0.005) on a scale of 1-10. There was a statistically significant (p<.05) improvement in photopic and scotopic contrast sensitivity and patient satisfaction.
Keywords: intraocular lens • optical properties • cataract