Purpose: To describe a new surgical technique for deep, anterior lamellar keratoplasty using a viscoelastic for dissection of Descemet's membrane (DM) from the posterior stroma.
Methods: Through a paracentesis, aqueous was exchanged by air to visualize the posterior corneal surface-i.e., the air-to-endothelium interface. Using the interface as a reference plane, a 30 gauge needle was inserted into the cornea to just anterior to DM. Viscoelastic was injected to separate DM from the posterior stroma, and a recipient, anterior lamella was excised. A full-thickness donor button was sutured into the recipient bed, after stripping its DM.
Results: In 25 eye bank eyes, the procedure could be completed in 20 eyes; in 5 eyes, DM ruptured during visco-dissection. With light microscopy, dissection depth was located at the level of DM. In two patient eyes the procedure could be completed. In a third patient eye DM ruptured during visco-dissection, and the procedure was converted into a penetrating keratoplasty.
Conclusion: Using visco-dissection, a lamellar keratoplasty can be performed quickly, with the donor-to-recipient interface just above the recipient DM, i.e., with a nearly perfect anatomical replacement of all corneal stroma. There is substantial risk of rupture or microperforation of DM during surgery.