Early Deep Anterior Lamellar Keratoplasty (DALK) for Acanthamoeba Keratitis Poorly Responsive to Medical Treatment

PURPOSE: To evaluate the success (eradication of infection) or failure (recurrence of infection in the cornea or sclera, or endophthalmitis) of early therapeutic deep anterior lamellar keratoplasty (DALK) for active Acanthamoeba keratitis (AK) poorly responsive to medical treatment. METHODS: Retrospective, noncomparative case series of 11 patients (11 eyes) affected by active AK poorly responsive to medical treatment who underwent early therapeutic DALK. Surgery was performed in all cases within 30 to 60 days from the onset of symptoms. Corneal ulcer depth was less than 300 μm in all cases. A 3-drug combination (chlorhexidine gluconate, propamidine isethionate, and neomycin sulfate) was the antiamoebic protocol used preoperatively and postoperatively. Cannula big bubble and "layer-by-layer" manual dissection techniques were performed. Eradication of infection, episodes of rejection, postoperative endothelial cell density, and the best spectacle-corrected visual acuity were evaluated. Histologic examination of surgical margins was performed, and margin clearance was assessed. Mean follow-up was approximately 2 years. RESULTS: Four descemetic DALK and 7 predescemetic DALK were performed. One small Descemet membrane rupture occurred. Peripheral surgical margins were free of infection in all cases. Deep surgical margins not free from infection were found in 2 cases. However, no episode of infection recurrence was observed. The postoperative average best spectacle-corrected visual acuity was 0.8 (range, 0.6-1.0). No case of rejection was recorded. CONCLUSIONS: Early therapeutic DALK could be considered a new approach to eradicate active infection in AK cases poorly responsive to medical treatment, with significant ulcer in the optical zone. Further studies are needed to validate this new indication for DALK.