To develop a laboratory model to study intracorneal keratoprosthesisimplantation.
A combination microkeratome and artificial anterior chamber system wasused to create a hinged lamellar keratectomy on 13 human corneas. After reflectingthe flap, the posterior stroma was trephined at either 2.5 or 3.0 mm. A modelkeratoprosthesis was positioned in the bed. The flap was sutured closed. Intrachamberpressure was increased, and wound leak pressure was recorded. The anteriorcorneal lamella was trephined at either 3.0 or 3.5 mm to expose the keratoprosthesis.Leak pressure was again determined.
After keratoprosthesis placement and prior to anterior trephination,all 13 corneas were watertight at maximum attainable intrachamber pressures.With posterior/anterior trephination combinations of 2.5/3.0 mm, 2.5/3.5 mm,or 3.0/3.5 mm, mean ± SD wound leak pressure occurred at95 ± 12 mm Hg, 32 ± 7 mm Hg, or 59 ± 12mm Hg, respectively (P<.01).
With a posterior trephination of 2.5 mm, there is significant keratoprosthesis-corneainterface destabilization between a 3.0- and 3.5-mm anterior trephination.For an anterior trephination of 3.5 mm, interface destabilization improvesby increasing the posterior trephination to 3.0 mm.
An intracorneal keratoprosthesis may be implanted using microkeratomeassistance. Our laboratory model provides a useful method for examining arange of posterior and anterior trephination diameters and their effects onthe mechanical stability of intracorneal keratoprosthesis placement.