Three types of corneal transplants
The cornea, the transparent front “window of the eye”, is responsible for about two thirds of the focusing power of the eye.
Corneal tissue can become damaged through disease or trauma. This damage can cause scar tissue and opacities in the normally-clear cornea, resulting in a reduction in visual acuity.
If the cornea develops visually significant opacities or irregularities, a corneal transplant procedure can be performed. A corneal transplant involves replacing a diseased or scarred cornea with a new cornea or specific corneal layers tissue.
What are the differences between PK, DSAEK and DMEK?
(full thickness traditional cornea transplant)
(partial thickness posterior cornea transplant)
|DMEK (Single layer of cells and supporting membrane)|
|Typical time for visual improvement||6-12 months||4-6 weeks||2 weeks|
|Rejection rates at 2 years||17%||9%||.7%|
|Visits for suture adjustment||6-12 visits||2-3 visits||1|
|Time of surgery||45-60 mins.||45-60 mins.||15-20 min.|
|Wound size||7.5 mm diameter circle||3.2 mm linear||Less than 2.4 mm|
|Graft thickness||550 microns||60-100 microns||10 microns|
|Contact lens required||Rigid gas permeable (often)||Not required||None|
|Induced astigmatism||High regular and Irregular astigmatism possible||Minimal to no induced astigmatism||None|
|Indications for surgery||Cornea scar, keratoconus, pellucid marginal degeneration, corneal ulcer||Fuch’s endothelial dystrophy, cornea edema, pseudophakic bullous keratopathy||Fuch’s endothelial dystrophy, cornea edema, pseudophakic bullous keratopathy|
Layers of the cornea
3 types of corneal transplants