title: Aberration and contrast sensitivity comparison of aspherical and monofocal and multifocal intraocular lens eyes.
abstract: BACKGROUND
  Higher-order aberrations and contrast sensitivity were evaluated in patients who underwent phacoemulsification cataract extraction followed by implantation of aspherical, monofocal or multifocal intraocular lens (IOL) replacements.
  
  
  METHODS
  In this comparative trial, 124 patients with an average age of 66.8+/-5.2 years and their 124 eyes were randomly divided into three surgical implantation groups to receive one of three types of IOLs in replacement of cataract lenses. The patients of group 1 were given an aspherical IOL Z9001 (AMO, Santa Ana, CA, USA) replacement, and group 2 was implanted a monofocal IOL SA60AT (Alcon, Fort Worth, TX, USA) and group 3 the multifocal IOL SA40N (AMO). Post-surgical best-corrected visual acuity, corneal aberrations, total ocular aberrations, pupil diameters, capsulorhexsis sizes and contrast sensitivity were measured and compared.
  
  
  RESULTS
  There was no statistical difference for mean best-corrected visual acuity, pupil diameter, curvilinear capsulorhexis size and corneal aberration among the three groups. For the spherical aberration, fourth-order higher-order aberration and total ocular higher-order aberration, the SA40N group was higher than the SA60AT group and the SA60AT group was higher than the Z9001 group, and the differences between the three groups were statistically significant for these measurements. Contrast sensitivity was higher for the Z9001 group than the SA60AT group and the SA60AT group was higher than the SA40N group, and the difference was statistically significant in all the spatial frequencies of 3, 6, 12 and 18.
  
  
  CONCLUSIONS
  Although the multifocal IOL can provide near vision, it can increase higher-order aberration and negatively influence contrast sensitivity. However, the aspherical IOL can reduce aberration and improve contrast sensitivity as compared with the monofocal IOL.
authors.affiliation: Zhongshan Ophthalmic Center, Sun-Yat-Sen University, State Key Laboratory of Opthalmology, and The Second Affiliated Hospital, Guanzhou Medical College, Guangzhou, China.
authors.forename: Mingbing
authors.initials: M
authors.lastname: Zeng
authors.forename: Yizhi
authors.initials: Y
authors.lastname: Liu
authors.forename: Xialin
authors.initials: X
authors.lastname: Liu
authors.forename: Zhaohui
authors.initials: Z
authors.lastname: Yuan
authors.forename: Lixia
authors.initials: L
authors.lastname: Luo
authors.forename: Yuanlin
authors.initials: Y
authors.lastname: Xia
authors.forename: Yangfa
authors.initials: Y
authors.lastname: Zeng
mesh_terms: D000368:Aged; D015350:Contrast Sensitivity / Q000502:physiology*; D003315:Cornea / Q000503:physiopathology*; D019466:Glare; D006801:Humans; D019654:Lens Implantation, Intraocular; D007910:Lenses, Intraocular; D008875:Middle Aged; D018918:Phacoemulsification; D019591:Pseudophakia / Q000503:physiopathology*; D012030:Refractive Errors / Q000503:physiopathology*; D014792:Visual Acuity