Comparison of clinical outcomes, complications and patient satisfaction following deep anterior lamellar keratoplasty and penetrating keratoplasty.

Background: Keratoplasty is a surgical procedure in which a damaged or diseased cornea is replaced with healthy donor tissue, thereby restoring vision. Recent advancements have led to the replacement of penetrating keratoplasty (PKP) with the more selective deep anterior lamellar keratoplasty (DALK) procedure, especially for treating keratoconus. Although DALK typically has a shorter recovery time, less pain and a lower risk of rejection, PKP is still being performed for more severe corneal diseases. A comparative study of clinical profiles, treatment outcomes and patient-reported satisfaction will provide valuable insights into the cost-effectiveness, impact on quality of life and ability of each procedure to treat different pathologies of the cornea. Here, we aimed to compare the clinical and subjective outcomes of DALK with those of the PKP at a single center in the Kingdom of Saudi Arabia.

Methods: This retrospective cohort study included eyes that underwent either PKP or DALK from January 2017 to January 2021. The demographic features, indications, best corrected visual acuity (BCVA) and complications of the patients were recorded for both groups, analyzed and compared. A subgroup of eyes with keratoconus was analyzed separately and compared to the larger group. A 6-item survey was conducted via telephone to assess patient satisfaction and expectation, and the results were compared between the two procedures. The chi-square test or Fisher's exact test for categorical variables or the t test or Kruskal‒Wallis test for continuous variables were used as appropriate for all comparisons, and the level of significance was set at α = 0.05.

Results: A total of 97 patients were included. PKP and DALK were performed on 63 and 39 eyes, respectively. Patients who underwent DALK were younger (mean ± standard deviation 31 ± 10.82 years versus 43 ± 26.89 years for patients who underwent PKP). The most frequent indication for PKP was keratoconus (35.5%); however, in 97.4% of the eyes undergoing DALK, the indication was keratoconus. In both groups, visual acuity and refractive error improved, but the postoperative corrected distance visual acuity in the DALK group (0.3 log MAR) was noticeably greater than that in the PKP group (0.6 log MAR). Compared with PKP, DALK may carry a lower risk of early graft edema and rejection. Overall, the reported postoperative patient satisfaction was similar for both procedures.

Conclusion: The findings highlight the effectiveness of PKP and DALK in improving visual acuity and emphasize the importance of considering patient-reported outcomes in evaluating success. DALK has been demonstrated to be beneficial for protecting the corneal endothelium and lowering the risk of complications and graft rejection.