Occurs when the donor cornea doesn't retain the transparency sufficient for adequate vision. The most common cause is endothelial cells dysfunction.
Other causes include sub-optimal condition of donor tissue, intraocular inflammation, hypotony due to ciliary body dysfunction in a traumatized eye, endothelial trauma during surgery, vitreous or iris tissue adherence to endothelium and preexisting glaucoma.
Clinical Features
Symptoms: hazy or blurred vision
Uncommon complication of penetrating keratoplasty.
Hazy and graft thickening associated with microcystic edema and multiple stromal or Descemet's folds.
Management
Intensive instillation of topical steroids around the clock to diminish inflammation.
Regrafting in cases with persistent corneal edema.
Donor button should be sent for pathologic evaluation.