Aberrations play a significant role in the visual process and can be divided in lower-order and higher-order aberrations. The former can be measured using the commercially available IOL Master (Carl Zeiss Meditec AG, Germany) and have profound influence on visual acuity. Higher-order aberrations do not significantly influence visual acuity but affect the quality of vision and can cause halos, double vision, and night vision disturbances.

Background Cataract surgery has become a routine procedure in the developed countries. During this surgery, a foldable intraocular lens is usually inserted into the capsular bag. However, these lenses do not account for individual optical biometry data or aberrations. Therefore, it is important to provide data for ametropic and emmetropic eyes as this information might improve future intraocular lens design and lead to individually adapted lenses for yielding optimal visual acuity and quality results.

The aim of the present study is to clarify the correlation between refractive errors/axial eye length and spherical aberrations of the cornea.

Inclusion Criteria:

• men and women aged between 40 and 60 years
• normal findings in the medical history unless the investigator considers an abnormality to be clinically irrelevant
• normal ophthalmic findings unless the investigator considers an abnormality to be clinically irrelevant

Exclusion Criteria:

• presence of any corneal or retinal disease
• Dry eye syndrome
• high astigmatism (>1 diopter)
• history of refractive surgery
• abuse of alcoholic beverages
• participation in a clinical trial in the 3 weeks preceding the study
• symptoms of a clinically relevant illness in the 3 weeks before the study day
• pregnancy

The participants will be selected by the Department of Clinical Pharmacology