Choose the transplant by the diseased corneal layer
A modern corneal-transplant opinion should begin with anatomy rather than a generic request for a donor cornea. Slit-lamp examination, corneal topography or tomography, pachymetry and—when endothelial disease is suspected—endothelial assessment help determine whether the problem is predominantly endothelial, stromal, full-thickness or part of a more complex ocular-surface disorder.
DMEK and DSAEK target endothelial disease
University Hospital Cologne, Freiburg and Charité describe posterior lamellar techniques that replace diseased inner corneal layers. In DMEK, the transplanted tissue is essentially Descemet membrane with donor endothelial cells; DSAEK includes a thin layer of posterior stroma as well. These approaches can avoid full-thickness replacement when the anterior cornea remains suitable.
DMEK uses an air or gas bubble and may require rebubbling
Cologne describes DMEK as a stitch-free procedure in which the thin graft is attached from inside the eye with an air or gas bubble. Patients may need supine positioning in the early postoperative period, frequent eye drops and pressure checks. If part of the graft detaches, an additional air injection ('rebubbling') may be needed. International patients should include this possibility in both travel and financial planning.
DALK preserves healthy endothelium in selected anterior disease
DALK replaces diseased anterior corneal stroma while retaining the recipient's Descemet membrane and endothelium when those deeper layers are healthy. It may be considered in selected keratoconus or stromal disease. Freiburg explicitly notes that the choice between DALK and penetrating keratoplasty must be assessed case by case rather than assumed from the diagnosis alone.
Penetrating keratoplasty replaces the full corneal thickness
When disease or scarring involves the cornea in a way that is not suitable for a layer-selective procedure, penetrating keratoplasty may still be necessary. Freiburg describes full-thickness transplantation with fine nylon sutures that can remain for many months during healing. This creates a different recovery and follow-up pathway from stitch-free endothelial transplantation.
Donor tissue and cornea-bank logistics are part of the plan
University Hospital Cologne operates its own cornea bank for donor-tissue preparation, quality assurance and waiting-list coordination. International patients should not assume that donor tissue is automatically available for a preferred travel date. Ask the treating center how tissue allocation, scheduling and prepayment interact before booking travel.
Send records that identify the affected layer and surgical complexity
A German cornea team can review the case more efficiently when the records show both the diagnosis and the structural reason transplantation is being considered.
- Recent slit-lamp ophthalmology report
- Corneal topography or tomography / Pentacam if available
- Pachymetry / corneal-thickness measurements
- Endothelial cell count or specular microscopy if performed
- Current refraction and best-corrected visual acuity
- Diagnosis and duration of corneal edema, dystrophy, keratoconus or scarring
- Prior cataract, glaucoma, refractive or corneal surgery reports
- History of herpes keratitis, corneal infection or ocular-surface disease
- Current eye drops, especially glaucoma or steroid treatment
- Lens status (natural lens, pseudophakia or aphakia) and IOL details if known
Plan postoperative follow-up before returning home
The first days and weeks after DMEK differ substantially from the long suture-management period after penetrating keratoplasty. Ask when the first checks are required, whether positioning is needed, who will monitor intraocular pressure, what would trigger urgent review, whether rebubbling is included in the planned pathway, and which long-term examinations can be transferred to an ophthalmologist at home.
Official sources
Sources last checked 2026-09-14. Ophthalmic treatment can be time-sensitive, so confirm current recommendations directly with the treating eye team.
- DMEK – minimally invasive endothelial corneal transplantation — University Hospital Cologne ↗
- DALK – deep anterior lamellar keratoplasty — University Hospital Cologne ↗
- Corneal transplantation and cornea-bank information — University Hospital Cologne ↗
- Keratoplasty – penetrating and lamellar transplantation — University Medical Center Freiburg ↗
- DSAEK / DMEK – posterior lamellar keratoplasty — University Medical Center Freiburg ↗
- Corneal transplantation – DSAEK, DMEK and DALK — Charité – Universitätsmedizin Berlin ↗