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

Cannula DALK Versus Needle DALK for Keratoconus

PURPOSE:: To evaluate outcomes and possible advantages of 2 different techniques of deep anterior lamellar keratoplasty (DALK) in patients with keratoconus: cannula big-bubble DALK and needle big-bubble DALK (Anwar technique). METHODS:: This is a retrospective, nonconsecutive, comparative study of 507 eyes affected by keratoconus that underwent DALK between 2002 and 2012. Needle DALK and cannula DALK techniques were performed in 266 eyes and 241 eyes, respectively. When big bubble (BB) failed, air viscobubble (AVB) was used as a rescue bubble technique. When AVB failed, manual dissection was performed. Main outcomes analyzed were the frequency of descemetic deep anterior lamellar keratoplasty (dDALK) and predescemetic deep anterior lamellar keratoplasty (pdDALK), BB and AVB formation, Descemet membrane rupture, and penetrating keratoplasty conversion. RESULTS:: The rate of dDALK achieved was higher (P < 0.01) in the cannula DALK group (94%; 198 BB and 28 AVB) than in the needle group (78%; 161 BB and 46 AVB). The remainder of cases involved pdDALK: 59 cases (22%) and 15 cases (6%) of the needle DALK group and cannula DALK group, respectively. Microperforation occurred in 18 cases spread between both groups. Macroperforation occurred in 5 cases in the needle DALK group. A double chamber occurred in seven cases, between both groups. No penetrating keratoplasty conversion was needed. CONCLUSIONS:: The use of a smooth cannula during the DALK procedure yields a statistically higher percentage of dDALK and makes the maneuver more manageable compared with air injection with a needle. When BB fails, AVB seems to be a good rescue technique to achieve dDALK

Early Deep Anterior Lamellar Keratoplasty (DALK) for Acanthamoeba Keratitis-How to Define Early? Reply

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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