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donor tissue. I would advise creating a deep lamellar cut using a big-bubble technique or a femtosecond laser. The diameter must be at least the size of the flap (approximately 9.0 mm overall). The goal must be to restore the curvature of the cornea and create a translucent cornea without a scar. The depth of removal of the anterior stroma must be more than 70% of the central thickness. Among the things that have to be discussed with the patient are the visual and refractive outcomes, interface-related problems, and refractive correction after the surgery. Once the sutures are removed, the final refractive outcome can be managed by performing a refractive lens exchange. The last suggested option, a (penetrating) mushroom-shaped keratoplasty, is not yet necessary because the endothelial cell count remains the same after excimer laser surgery. The visual outcomes of a penetrating procedure are potentially better than those of a lamellar procedure; however, the wound architecture, graft rejection period, and long period of topical medication use make this treatment less preferable than lamellar grafting. Annette J.M. Geerards, MD Rotterdam, the Netherlands

rejection and early cataract formation, and the patient must be informed about this. As an alternative, the corneal flap can be relifted where there is epithelial ingrowth and removed. Removing the epithelial ingrowth will allow the corneal flap to heal. Then, pachymetry-assisted laser keratoplasty can be performed using an excimer laser; however, this will entail 2 separate operations. The reason for epithelial removal is because the trapped epithelium undergoes degeneration, which forms foamy cells. These foamy cells will be soft and liquefied and will not ablate uniformly with an excimer laser. Without the epithelial ingrowth, pachymetry-assisted laser keratoplasty would be easy to perform because the excimer laser is guided by pachymetry and not topography. The residual bed can be set to a minimum of 80 mm using an Amaris laser (Schwind). However, in this case, I would not advise this because of the presence of epithelial ingrowth of at least 60 mm estimated from the corneal OCT. Because of the thinness of the cornea, lamellar keratoplasty is required and for the best optical quality, DALK is still the top option. Jerry Tan, MD Singapore

- This case has many interesting clinical dilemmas and many learning points. Relift enhancements increase the risk for epithelial ingrowth, especially in microkeratome cuts with their sloping edges. In my experience, a higher number of relift enhancements increases the risk for epithelial ingrowth. Hyperopic relift enhancements also increase the risk for epithelial ingrowth due to excimer laser ablation damage to the edge of the stromal bed exposed by relifting the microkeratome flap. Mixed astigmatism is one of the hardest types of corrections to perform because excimer laser algorithms in many laser machines are not perfected for mixed astigmatism. There is no real possibility of treatment in this patient because he has a refraction of +8.00 6.00  150. Recurrent epithelial ingrowths are exceedingly difficult to treat and cause irregular astigmatism with refractive problems. There is also an increased risk for infection with recurrent epithelial ingrowths. In this case, I believe the simplest method to resolve the problem is to perform DALK; exposing Descemet layer using a big-bubble technique will give the best interface and quality of vision. However, there is always a risk for Descemet perforation, particularly in younger patients. In such cases, a full corneal transplantation would be required. There is also a risk for

- I would spend some time and discuss with the patient all possible options. This is a complicated case, and medicolegal action is possible. Thus, attention to adequate chair time and thorough documentation is warranted. In my mind, there are 5 possible options. The first is to relift the flap, or part of it, to remove the large area of ingrowth around 3 o'clock on the stromal side and the underside of the flap. Then, suture the flap with 7 interrupted sutures to avoid regrowth. (The corneal epithelium usually needs a feeder fistula to grow under the flap. It usually regresses if it has no direct relation to the tear film). If this were successful, I would remove the sutures in approximately 1 month (removing those that loosen before that time) and follow the refractions, Placido-disk topography changes or color light-emitting diode reflection topography, and epithelial remodeling on AS-OCT for signs of stabilization.1 I would not trust Scheimpflug-based imaging because it might be biased by the corneal opacity. In my experience, the cornea will be quite stable in approximately 3 to 4 months. If that occurs, I would consider combined topography-guided photorefractive keratectomy (PRK) followed by a 50 mm phototherapeutic keratectomy to use the epithelium as a masking agent.2–4 (Almost invariably it will be quite abnormal over the scar, which usually flattens the cornea.) This would normalize the anterior corneal curvature with the use

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of a topographic neutralization technique to treat most of the refractive error. I would combine this with highfluence corneal collagen crosslinking as an additional means of reducing scarring by keratocyte manipulation, as previously reported.5 I think this is a viable option because the scar does not cover the whole central cornea, although at best it will leave some photophobia and morbidity due to the remaining scar. A second PRK may be required and would probably much simpler if the refractive target is not met. I believe this would carry the great advantage of avoiding a graft. The second option would be to amputate the flap and try a rigid gas-permeable (RGP) contact lens after reepithelialization of the bare stromal surface. This may be combined with MMC use to avoid significant scarring. The third option is a lamellar corneal allograft. If my assessment and the patient's choice pointed toward a graft solution, I would suggest DALK because in my experience, it provides better visual rehabilitation results and because the scar seems to run quite deep past the middle and into the posterior stroma The fourth option is a penetrating graft. If PKP were an option, it would be mushroom shaped and achieved with the aid of a femtosecond laser on the host and graft and would be my choice of technique. Last, doing the minimum is always a choice to discuss with the patient. This would entail waiting to see what happens with the scar and ingrowth while possibly using an RGP lens for temporary visual rehabilitation. John A. Kanellopoulos, MD Athens, Greece REFERENCES 1. Kanellopoulos AJ, Asimellis G. In vivo three-dimensional corneal epithelium imaging in normal eyes by anterior-segment optical coherence tomography: a clinical reference study. Cornea 2013; 32:1493–1498 2. Kanellopoulos AJ. Topography-guided custom retreatments in 27 symptomatic eyes. J Refract Surg 2005; 21:S513–S518 3. Kanellopoulos AJ, Pe LH. Wavefront-guided enhancements using the WaveLight excimer laser in symptomatic eyes previously treated with LASIK. J Refract Surg 2006; 22:345–349 4. Kanellopoulos AJ. The management of cornea blindness from severe corneal scarring, with the Athens Protocol (transepithelial topography-guided PRK therapeutic remodeling, combined with same-day, collagen cross-linking). Clin Ophthalmol 2012; 6:87–90. Available at: http://www.ncbi.nlm.nih.gov/pmc/articles/ PMC3280100/pdf/opth-6-087.pdf. Accessed July 21, 2014 5. Kanellopoulos AJ. Novel myopic refractive correction with transepithelial very high-fluence collagen cross-linking applied in a customized pattern: early clinical results of a feasibility study. Clin Ophthalmol 2014; 8:697–702. Available at: http://www.ncbi. nlm.nih.gov/pmc/articles/PMC3984063/pdf/opth-8-697.pdf. Accessed July 21, 2014

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EDITOR’S COMMENTS This case demonstrates that (multiple) retreatments after corneal laser surgery may lead to epithelial ingrowth with significant irregular astigmatism, melting of the corneal flap and bed, and a decreased overall quality of vision. Fitting a contact lens was for some years an acceptable solution and should, in my view, be recommended as an initial treatment in these cases. However, the occurrence of a bacterial ulcer increased the irregular astigmatism, probably due to further melting of the corneal flap and stroma. Relifting the flap with potential removal of epithelial ingrowth appears not to be a viable option to restore the quality of vision. A topography-guided excimer laser technique to remove the scar, although attractive from a conceptual viewpoint, has not been proven yet to provide predictable visual outcomes in irregular corneas with variations in corneal thicknesses. As proposed by the discussants, a lamellar keratoplasty procedure appears to be a valuable option. A deep lamellar procedure (DALK) is the preferred technique over an anterior lamellar procedure because the corneal endothelium is saved, which eliminates the risk for endothelial rejection; it increases long-term graft survival; and it leads to better vision compared with anterior lamellar procedures. The use of a femtosecond laser appears questionable because the original flap diameter (with peripheral epithelial ingrowth) is 9.5 mm and it would be difficult to obtain a mushroom-shaped deep lamellar configuration with this large diameter and perfect centration on the previous flap. Therefore, I would recommend manual DALK using a big-bubble technique. Finally, the patient must be informed that after DALK, contact lens wear or additional procedures for correction of refractive ametropia or astigmatism may be needed.1

Rudy Nuijts, MD Maastricht, Netherlands REFERENCE 1. Cheng YYY, Visser N, Schouten JS, Wijdh R-J, Pels E, van Cleynenbreugel H, Eggink CA, Zaal MJW, Rijneveld WJ, Nuijts RMMA. Endothelial cell loss and visual outcome of deep anterior lamellar keratoplasty versus penetrating keratoplasty: a randomized multicenter clinical trial. Ophthalmology 2011; 118:302–309

J CATARACT REFRACT SURG - VOL 40, SEPTEMBER 2014

September consultation #7.

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