Wavefront aberrations, depth of focus, and contrast sensitivity with aspheric and spherical intraocular lenses: fellow-eye study.

PURPOSE

To compare wavefront aberration, depth of focus, contrast sensitivity, and in vivo modulation transfer function (MTF) after fellow-eye implantation of aspheric and spherical intraocular lenses (IOLs).

SETTINGS

Department of Ophthalmology, St. Thomas' Hospital, London, United Kingdom.

METHODS

This prospective randomized controlled study comprised patients with bilateral cataract who received an aspheric AcrySof SN60WF IOL or a spherical AcrySof SN60AT IOL in the first eye and the other IOL in the second eye. Assessments at 3 and 6 months included 100% and 9% logMAR best corrected visual acuity (BCVA) and photopic and mesopic functional acuity contrast testing. Total internal and corneal aberrations and depth of focus were computed. Distance-corrected near logMAR acuity was available at 12 months.

RESULTS

At 3 and 6 months, there was no significant difference in 100% and 9% BCVA or photopic contrast sensitivity. Mesopic contrast sensitivity was better and total and internal spherical aberrations were significantly less with the aspheric IOL. Total and internal eye vertical coma was reduced with aspheric IOL. Total MTF was not significantly different between groups. The aspheric IOL group had 0.46 diopter less depth of focus than the spherical IOL group at 6 months (P<.05). Distance-corrected near acuity was significantly better with the spherical IOL.

CONCLUSIONS

Aspheric IOLs significantly reduced spherical aberration, improving mesopic contrast sensitivity. Vertical coma was reduced with aspheric IOLs. Reduction of aberrations may be responsible for reduced depth of focus with aspheric IOLs. This may be disadvantageous for near vision and reading ability.