Descemet Endothelial Thickness Comparison Trial

Inclusion Criteria:

* Damaged or diseased endothelium from Fuchs or Pseudophakic Bullous Keratopathy
* Good candidates for corneal transplantation for either DMEK or DSAEK
* Willingness and ability to undergo a cornea transplantation
* Willingness to participate in follow-up visits

Exclusion Criteria:

* Participants who are decisionally and/or cognitively impaired
* Participants who are not suitable for the DMEK or DSAEK surgeries
* Prior Endothelial Keratoplasty (EK) or any other ophthalmic surgery except uncomplicated cataract surgery
* Indication for surgery that is not suitable for EK (e.g. keratoconus, stromal dystrophies and scars)
* Presence of a condition that increases the probability for failure (e.g., heavily vascularized cornea, uncontrolled uveitis)
* Other primary endothelial dysfunction conditions including posterior polymorphous corneal dystrophy and congenital hereditary corneal dystrophy
* Aphakia, or anterior chamber intraocular lens (IOL) in study eye prior to or anticipated during EK
* Planned intraocular lens exchange of an anterior chamber IOL with a posterior chamber IOL in study at time of study EK
* Pre-operative central sub-epithelial or stromal scarring that the investigator believes is visually significant and could impact post-operative stromal clarity assessment
* Peripheral anterior synechiae (iris to angle) in the angle greater than a total of three clock hours
* Hypotony (Intraocular pressure \<10mmHg)
* Uncontrolled (defined as intraocular pressure \>25mmHg) glaucoma Visually significant optic nerve or macular pathology
* Visually significant optic nerve or macular pathology