Optical quality comparison of six diffractive and one refractive multifocal intraocular lenses: role of lens add power and foci light distribution
Session Details
Session Title: Presented Poster Session: Multifocal IOLs
Venue: Poster Village: Pod 1
First Author: : J.Gil SPAIN
Co Author(s): : F. Vega C. Varon G. Cardona M. Millan J. Buil
Abstract Details
Purpose:
To compare the optical quality of seven different multifocal intraocular lens (MIOL) designs: six diffractive MIOLs (AcrySof ReSTOR SV25T0; AT LISA 809M; AT LISA TRI 839MP; Tecnis ZKB00; Tecnis ZLB00 and Tecnis Symfony ZXR00) and one refractive MIOL (Miniwell Ready) as a function of light energy distribution and lens addition.
Setting:
Research facilities of the Research Group of Applied Optics & Image Processing of the Department of Optics and Optometry, Technical University of Catalonia-BARCELONA TECH, Terrassa, Spain.
Methods:
A modified-ISO eye model was used for in-vitro testing of the lenses. The experiments included artificial pupil diameters of 3.0 mm (simulating photopic conditions) and 4.5 mm (mesopic conditions). Light distribution at the foci of the MIOLs was experimentally determined from image analysis. The optical quality of the MIOLs was derived from the value of the modulation transfer function (MTF) at the best focus planes and through-focus MTF curves at 50 cycles/mm.
Results:
Light distribution amongst foci was influenced by lens design and add power. For a 3.0 mm pupil, the best optical quality at distance was achieved by the ReSTOR SV25T0 (MTF score of 0.40). The other MIOLs obtained similar MTF scores (approximately 0.25). At intermediate distances (60-80 cm), the Symfony MIOL showed the best quality (almost 0.40), followed by the AT LISA TRI 839MP (score 0.10). The Miniwell Ready did not present a clearly defined intermediate focus. Intermediate MTF values with the other MIOLs were poor. The best optical quality at near corresponded to the ZLB00 and ZKB00 (scores of 0.3).
Conclusions:
In both diffractive and refractive MIOLs, lens design is determinant of light distribution at each lens foci. Apodized diffractive designs provide more light energy to the distant focus, while undermining light reaching the near focus. The extended focus design provided by the Symfony lens offered the best performance at intermediate distances, when compared with the other MIOLs under study, including the refractive Miniwell Ready, which presented similar optical quality at far and near distances. Particular care must be exercised when comparing optical quality at predetermined constant distances between lens designs with different add powers.
Financial Disclosure:
NONE
