Visual outcomes and recurrence rate of macular corneal dystrophy following phototherapeutic keratectomy in Saudi Arabia

PURPOSE: The purpose of the study was to evaluate the visual outcomes and recurrence rate of patients with macular corneal dystrophy (MCD) who have undergone phototherapeutic keratectomy (PTK). METHODS: This retrospective, single-centered study enrolled patients from King Khaled Eye Specialist Hospital who had undergone PTK for MCD between 2000 and 2020. Pre-, intra-, and post-operative data were collected, and the primary outcome measures included uncorrected visual acuity, best-corrected visual acuity (BCVA), spherical equivalent, central keratometry, keratometric astigmatism, recurrence rate, and necessity of subsequent surgery. RESULTS: This study evaluated 42 eyes of 29 patients. BCVA improved from 0.41 (+/- 0.17) preoperatively to 0.30 (+/- 0.16) postoperatively. Sixteen out of 42 eyes (38%) had the recurrence of macular dystrophy deposits within the stroma; the average time from PTK to recurrence was 37 months (range: 5.5-115.4 months). The overall success rate of PTK at 2 years was 44.8%. Eleven eyes (26%) required subsequent surgery following PTK at an average of 43 months postoperatively. Deeper ablation and longer application of mitomycin C (MMC) were both found to be statistically significant factors associated with visual improvement and lower recurrence rate following PTK. CONCLUSION: PTK can be considered a treatment modality for younger patients to defer keratoplasty to a later stage. Deeper ablation is associated with improved postoperative visual acuity, and longer application of MMC is associated with lower recurrence rates of MCD.