The goal of this retrospective study is to quantify the physiological lens tilt of the phakic eye.

The main question it aims to answer is:

-What influence does misalignment or tilting of IOLs have on visual quality?

Preoperative biometry data are compared with anterior segement OCT data.

Measurements were obtained using high-resolution swept-source optical coherence tomography. The influence of biometric measurements on tilt is analyzed.

The human (crystalline or phakic) lens is located in the capsular bag which is attached to zonules. Zonules are fibres, that hold the lens in place. In the course of life, an opacification on the lens occurs, which is called cataract. To replace the cloudy lens, cataract surgery is being performed and an artificial intraocular lens (IOL) is implanted in the eye, after the phakic lens is removed. Misalignment or tilting of IOLs can result in reduction of visual quality, therefore prediction of the position may be beneficial. Modern optical coherence tomography (OCT) devices already provide profound information about phakic lens tilt. Still there is little data on the values that influence the tilt of the crystalline lens. Before each cataract surgery, each eye is measured using biometry (IOL Master 700). However, a statement about the tilt cannot be made on the basis of the results of IOL Master 700. For this purpose, an anterior segment OCT is required (CASIA 2). In this study, preoperative biometry data are compared with anterior segment OCT data. A statistical analysis will then be performed to identify the biometric parameters that can predict phakic lens tilt.

Inclusion Criteria:

• Planned cataract surgery in one or both eyes
• Minimum age of 21 years

Exclusion Criteria:

• Opacities of the refracting media
• Measurement error in the context of preliminary investigation
• pseudophakia

Patients between 21 and 100 years who received preliminary examinations as part of cataract surgery