Comparison of Penetrating Keratoplasty and Deep Anterior Lamellar Keratoplasty Post-Operative Results among Keratoconus Patients

To compare post-operative results among keratoconus patients undergoing penetrating keratoplasty (PKP) in comparison with deep anterior lamellar keratoplasty (DALK) and to study the risk factors for transplant rejection.

In this retrospective cross-sectional study, the records of all keratoconus patients referred to Labbafinezhad Eye Hospital, Tehran, Iran, who underwent penetrating keratoplasty (PKP) or deep anterior lamellar keratoplasty (DALK) from 2006 to 2016, were investigated. For all patients entering the study information related to surgical corneal transplantation techniques, post-operative follow-up and post-operative results were recorded.

In total the records of 216 patients (106 in the PKP and 110 in the DALK group) were included. The rate of graft rejection was 13 % and 34.3 % in DALK and PKP groups respectively (P <0.001). The graft failure rate was 7.8 % in DALK and 2.4 % in PKP group (P = 0.12). No statistically significant difference in post- operation BCVA or the number of patients with astigmatism of more than 4 diopters was observed when comparing the study groups. The higher age of patients at the time of transplant, the presence of post-surgical vascularization, and interface complications were correlated with a higher chance of transplant rejection.

The rate of graft rejection is significantly higher after PKP than DALK among keratoconus patients undergoing corneal transplant. The higher age of patients at the time of transplant, the presence of post-surgical corneal vascularization and interface complications were the observed risk factors for graft failure in both groups.