Therapeutic penetrating keratoplasty: clinical outcome and evolution of endothelial cell density

To identify the influence of the underlying etiology on the outcome of therapeutic penetrating keratoplasty (PKP) in the management of corneal perforation, impending perforation or refractory corneal disease.

A retrospective observational case series with 28 patients (28 eyes) was performed. Patients were divided in two subgroups, based on the underlying ocular disease leading to the therapeutic PKP. Group I consisted of 15 patients (54%) with an infectious etiology, the other 13 patients (46%) with a noninfectious condition belonged to group II. Mean follow up was 23.2 months (median 21 months).

An enucleation could be avoided in all but two cases. In group I, 12 of 15 (80%) grafts remained clear, compared with only 3 of 13 (23%) in group II (p = 0.0004). Visual acuity (VA) amelioration was achieved in 20 of 28 patients (71%). In group I the postoperative VA was significantly better than preoperatively (p = 0.002); however, in group II the improvement was only borderline significant (p = 0.05). Overall five out of ten (50%) patients with a therapeutic PKP in group I had an endothelial cell density >or= 1900 cells/mm2 at the time of their last specular microscopy.

Our study demonstrates the importance of underlying etiology on the outcome of therapeutic PKP. Graft survival and postoperative visual acuity varied widely depending on the underlying ocular disease, and it was clear that therapeutic PKP has a much better prognosis in infectious conditions when compared with noninfectious conditions. We believe that these good results can justify the use of therapeutic PKP in selected cases of infectious keratitis.