This single-centre, prospective, controlled, non-interventional observational clinical study aims to characterize early postoperative corneal thickness behaviour after routine phacoemulsification cataract surgery in eyes with Fuchs endothelial corneal dystrophy (FECD) compared with non-FECD controls, using exclusively standard-of-care perioperative assessments. To compare central corneal thickness (CCT) six weeks postoperatively between FECD and non-FECD eyes, adjusting for baseline (preoperative) CCT.

All participants undergo routine phacoemulsification cataract surgery and routine perioperative assessments. Data are collected from the standard-of-care documentation at the following time points:

1. Preoperative baseline visit (routine cataract work-up)
2. Study specific postoperative follow-up at approximately 6 weeks. Each participant will attend a study-specific follow-up visit at 6 weeks postoperatively and contributes study-specific follow-up data up to this time point.

The routine clinical parameters assessed (as available per standard practice) include:

1. Medical history / baseline characteristics and documentation of ocular/systemic comor-bidities and topical medication
2. Best-corrected visual acuity (BCVA) (logMAR).
3. Intraocular pressure (IOP) measured by Goldmann applanation tonometry (GAT).
4. Slit-lamp examination (including assessment of corneal clarity/edema and anterior seg-ment findings) with fundoscopy as routinely documented.
5. Central corneal thickness (CCT) measurement using routine clinical devices. All meas-urements will be performed at a consistent time of day for each patient.
6. Anterior segment OCT (CASIA2).
7. Anterior segment Scheimpflug tomography (Pentacam Oculus AXL)
8. Endothelial cell assessment (ECC, CV, AVG, HEX, SD) examined with NIDEK® CEM-530 Specular Microscope