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