Bilateral versus unilateral penetrating graft in keratoconus.

A series of 105 penetrating grafts in keratoconus is analyzed. In 45 unilateral grafts, 15% developed allograft rejection (AR); in 30 bilateral grafts, there was AR in 13% of first eyes and in 17% of second eyes. The incidence of rejection in second eyes was three times greater within the first year after surgery than it was in first eyes. The interval between grafts performed on the first and second eyes demonstrates that with a mean interval of eight months, the incidence was 22%, and with a mean interval of 35 months, it was only 5%. None of the cases of AR caused definitive graft failure because of adequate warnings to the patient and prompt therapy. Visual acuity was 20/50 or better in the whole series in 91% of cases and 87% in the AR cases, it was the same in 87% of grafts.