Clinical Evaluation of Reproducibility of Keratometric Measurements and Influencing Factors in Cataract Patients

Clinical Evaluation of Reproducibility of Keratometric Measurements and Influencing Factors in Cataract Patients

The investigational device is an approved biometry device to perform biometric measurements preoperatively to calculate the needed IOL power.

First, two native measurements at the IOL Master will be performed. Thereafter randomly assigned artificial tears are instilled in the eye and biometry will be repeated within 30 seconds, as well as after 2 and 5 minutes.

At least 24hours after those measurements, two native measurements at the IOL Master will be performed. Thereafter, the not yet used artificial tears are instilled in the eye and biometry will be repeated within 30 seconds, as well as after 2 and 5 minutes.

Examinations will be implemented in accordance with the approved investigational plan on subjects and includes: repeated biometry without and with artificial tear drops.

Inclusion Criteria:

• diagnosed uni- or bilateral age-related cataract
• Age 40 to 95
• Normal findings in the medical history and physical examination unless the investigator considers an abnormality to be clinically irrelevant

Exclusion Criteria:

• Corneal abnormality (Corneal scaring)
• usage of artificial tears/eyedrops 24h before the examination
• necessity of any topical therapy of the eye (i.e. glaucoma)
• active ocular or nasal allergies or corneal or conjunctival infection
• abnormality of the nasolacrimal drainage apparatus
• dry eye severity level 4 (severe and/or disabling constant discomfort and visual symptoms, marked conjunctival injection, filamentary keratitis, mucus clumping, tear debris, ulceration, trichiasis, keratinization, symblepharon)
• lid deformities
• Preceding ocular surgery or trauma
• Pregnancy
• Lactation
• Uncontrolled systemic or ocular disease