Comparing an Intraoperative vs. a Standard Wavefront Device

To Collect and Compare Data With an Intraoperative Wavefront Device (HeLeNa) to a Standard Wavefront Device: an Explorative Pilot Study

Different technologies are in use for measuring wavefront aberrations, such as Hartmann-Shack wavefront aberrometry, Tscherning aberrometry, Laser Raytracing and automatic retinoscopy. While Hartmann-Shack wavefront aberrometry, the most widespread of these techniques, uses a lenslet array to record distortions of light bundles coming from a single source form the retina, Tscherning aberrometry uses a matrix of pinholes. Laser Ray Tracing in contrast measures the aberration of a laser beam at different locations. All three systems compare distorsions of the measured light beams with a perfect optical system to calculate the wavefront errors. Repeatability of wavefront devices was studied in young healthy subjects and different devices have been compared to each other. These results do not represent the typical cataract patient. Several factors, such as tear film instability and pupil size, have an influence on the measurements and these factors may change significantly with age. Intraoperative measured data could help to get a better information about wavefront aberrations.

Measurements of wavefront aberrations using an Hartmann-Shack device will be compared at different time points (pre-, intra-, postoperative).

Inclusion Criteria: Cataract Age 21 and older Able to understand the patient information Willing to follow the instructions and attend all follow-up visits Willing to sign informed consent prior to surgery Exclusion Criteria: Relevant other ophthalmic diseases that are likely to reduce the refractive outcome, such as pseudoexfoliation syndrome, traumatic cataract, severe corneal scars Previous ocular surgeries on the study eye Patients who are not able to cooperate, with eccentric fixation or insufficient ability to fixate (tremor, nystagmus) Pregnant or lactating women (pregnancy testing will be performed preoperatively on women of reproductive age)