5-year Outcomes of Converted Mushroom Keratoplasty from Intended DALK Mandate 9mm Diameter DALK as the Optimal Approach to Keratoconus.

Abstract Purpose To compare the 5-year outcomes of 9mm deep anterior lamellar keratoplasty (DALK) for keratoconus against those converted to mushroom keratoplasty (MK). Design Retrospective cohort study Methods . Setting Ospedali Privati “Villa Igea”, Department of Ophthalmology, Forli, Italy Patient or Study Population The medical records of all attempted DALKs (416 eyes) for the indication of keratoconus performed between January 2012 and January 2018 were evaluated, 68 (16.4%) of which were converted to MK and analysed as a separate cohort. The mean follow-up time was 33.8±15.1 months. Intervention or Observation Procedure(s) 9 mm DALK and MK (9 mm anterior lamella with 6 mm posterior lamella) Main Outcome Measures: Best corrected visual acuity (BCVA), refractive astigmatism, endothelial cell loss (ECL) at 5 years. Results Average BCVA at 5 years was 0.06±0.07 in DALK group and 0.09±0.15 in the MK group (p=0.88). Refractive astigmatism following suture removal (all visits later than 12 months) was slightly less in the DALK cohort (5-year DALK=2.16D±1.40, MK 3.02D±0.89, p=0.04, mean difference 0.86D (95%CI 0.71-1.01)). ECL was significantly higher in the MK group than in the DALK group at all follow up intervals (5-year DALK = 19.36%±21.47, MK 56.61%± 15.82, p Conclusions Excellent 5-year visual and clinical outcomes associated with a two-piece mushroom keratoplasty in cases converted from intended DALK mandate large diameter DALK (9mm) as the optimal surgical approach to keratoconus.