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Enhancement with surface ablation is not advantageous; because the cornea was previously deformed, subsequent excimer laser treatment would induce further spherical aberration. In addition, high hyperopic ablations are prone to regression and irregularity and have limited predictability. In cases of recurrent hyperopia after LASIK, RLE may be the best option. I would prefer a monofocal IOL for both eyes. Requirements for a multifocal IOL were not met in this case. There was no chance of excellent biometry, and a normal prolate cornea and good binocular function were not present. Standard monofocal IOLs have positive spherical aberration and can therefore partially compensate for the negative spherical aberration induced by the previous hyperopic ablation. Intraoperative autorefraction is useful after excimer laser surgery. I would consider lamellar graft surgery in this case of unsuccessful enhancement. Aylin Kılıc¸, MD Istanbul, Turkey

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approach is always successful. If creation of a new flap were required, I would have used a mechanical microkeratome to create a wider, deeper flap. It takes some force to lift a femtosecond laser–created flap, and the force might tear the corneal tissue. A microkeratome-created flap can be easily lifted without force. Because making a second cut, even with a microkeratome, does not completely prevent the formation of a thin sliver of tissue, I always try to lift the previous flap unless it is incomplete, too small, or dislocated. Photorefractive keratectomy (PRK) might be an option; however, hyperopic PRK in eyes with previous LASIK would have a high risk for subepithelial haze and regression. I would rather perform RLE if the patient does not want to risk flap complications. If this were a case of myopic regression, I would also try to lift the original flap. Alternatively, if I could determine the flap margin and approximate depth, I would create only a side cut inside the original flap margin using a femtosecond laser to prevent epithelial ingrowth. Ikuko Toda, MD, PhD Tokyo, Japan

REFERENCES lu G, Ertan A. Epithelial ingrowth after femtosecond 1. Kamburog laser-assisted in situ keratomileusis. Cornea 2008; 27:1122– 1125 2. Tran DB, Binder PS, Brame CL. LASIK flap revision using the IntraLase femtosecond laser. Int Ophthalmol Clin 2008; 48(1):51– 63 3. Vaddavalli PK, Yoo SH, Diakonis VF, Canto AP, Shah NV, Haddock LJ, Feuer WJ, Culbertson WW. Femtosecond laser-assisted retreatment for residual refractive errors after laser in situ keratomileusis. J Cataract Refractive Surg 2013; 39:1241–1247

- I would not have performed hyperopic LASIK in this patient who required more than +3.00 D of correction because of the possibility of regression and decreased quality of vision. Hyperopic correction by LASIK induces higher-order aberrations and sometimes results in loss of CDVA (with spectacles) and symptoms such as halo and glare. I would have suggested implantation of phakic IOLs (pIOLs) to this patient. However, patients with hyperopia often have a shallow anterior chamber and are thus not candidates for pIOLs. In that case, I would suggest multifocal contact lenses and wait to perform cataract surgery with implantation of multifocal IOLs. If this patient presented to me after initial hyperopic LASIK, I would try to lift the original flap. In my experience, flap lifting is always possible, even when the flap margin cannot be seen on slitlamp examination. I use fluorescein staining and/or light pressure at the peripheral cornea to find the flap margin. This

- I believe the risk related to creation of a new flap became too high from the moment the surgeon was not able to properly identify the edges of the flap. Often, preoperative high-resolution corneal optical coherence tomography (OCT) is helpful in this identification. Therefore, my primary approach for this patient would have been to perform personalized PRK with MMC 0.02% applied for 30 seconds, although the risk for regression and decentration might be relatively significant based on the excimer laser used. However, creating a new flap without properly identifying the limits of the old one can lead to more severe complications, such as deterioration in visual quality due to double interface syndrome. Furthermore, the new flap can be cut inside the old one, which is likely to create a buttonhole. Irregular astigmatism can also appear if the old flap slips or the new one is not positioned properly. Finally, attempting to relift an old flap created with a mechanical microkeratome creates a major risk for epithelial ingrowth. Refractive lens exchange might be a reasonable approach considering the high chance of regression and induced postoperative dryness. However, monovision with a monofocal IOL after a contact lens trial to test the patient's satisfaction and tolerance to monofocality is preferred over a multifocal IOL approach. The implantation of a multifocal IOL behind a

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reshaped cornea that probably already has a significant amount of spherical aberration and coma, combined with the risk for a hyperopic surprise in IOL calculation after refractive surgery and an approximate alignment of the different diopters (new corneal apex after a hyperopic treatment and geometric center of the IOL), would risk poor quality of vision. After the unsuccessful enhancement in the left eye, I am convinced the cornea should not be operated on again. Actually, it has 2 interfacesdthe new flap and the old flap. The curvature maps do not necessarily match the stromal curvature, as can be seen by the evolution of the central pachymetry, which increased from 585 mm to 605 mm 1 month after the enhancement because of the folds on the 2 interfaces. Then, 6 months after the enhancement, the central pachymetry is identical to that before the enhancement (581 mm), even though stromal loss occurred during the enhancement. Central keratometry is improving as time elapses. Thus, it is likely the cornea will continue to improve in the upcoming months. Indeed, stromal healing can take as long as 1 year. Thus, I would recommend that the patient wear rigid contact lenses to smooth the corneal surface. This clinical case highlights that managing complications after LASIK is extremely difficult with demanding patients, who often ask for enhancements. The key seems to be providing comprehensive information and support. Primum non nocere. Viridiana Kocaba, MD Lyons, France

- Although trying to lift the original flap is recommended and OCT or high-resolution OCT might provide better evaluation of the initial flap conditions, relifting is not plausible in some cases. In such cases, noncorneal refractive surgery can be considered. There are reports of higher complications with flap recutting than with flap relifting using a microkeratome1 as well as complications with retreatments performed with a femtosecond laser.2 If recutting is planned, a new deeper flap with a larger diameter is preferred.1 Particularly in hyperopic cases, such as the one presented here, this would lead to better outcomes and fewer risks. Even though ectasia after hyperopic LASIK can occur, the incidence is rare. In the near future, it might be possible to perform hyperopic refractive lenticule extraction under the previous flap. Due to potential regression and haze formation in hyperopic cases, the use of surface ablation in retreatments should be carefully weighed or avoided. However, the actual difference in the efficacy of hyperopic

treatments between LASIK and PRK is still uncertain.3 If the original regression had been myopic in this case, post-LASIK ectasia would have to be ruled out first. Then, if it were a case of mild to moderate residual myopia, PRK with MMC application could be performed. For higher myopia, pIOL implantation or RLE could be explored. In this case, RLE would have been an excellent alternative to the initial retreatment. Although there are risks with RLE, it is well accepted that hyperopic patients older than 45 years, and preferably with posterior vitreous detachment, can obtain excellent outcomes. However, RLE must be avoided in younger patients. Also, posthyperopic LASIK IOL calculations are less complicated than those after myopic LASIK.4 A spherical (positive spherical aberration) monofocal IOL is preferred. If available, a light-adjustable IOL and intraoperative wavefront analysis could be considered. Regarding how to proceed in treating this patient, I would evaluate patient performance with monovision and fit rigid contact lenses. Assuming that these alternatives are not satisfactory, refractive surgical solutions can be considered. The main problem in this case is the irregular astigmatism, which rules out conventional refractive surgery procedures such as another LASIK procedure, PRK, refractive lenticule extraction, RLE, or pIOL implantation. It is likely that wavefront or topography-guided smoothing or refractive treatments would recover CDVA, and concomitant use of MMC is highly recommended. This alternative may also be less invasive. Ideally, very-high-frequency ultrasound scanning is able to separate epithelial and stromal measurements and could be used to improve outcomes.5 Another option would be intrastromal corneal ring segment implantation; however, because of the folds and tissue scarring in this case, it may not improve the CDVA. The last option is keratoplasty, preferably anterior lamellar (superficial lamellar or pachymetry-assisted laser keratoplasty). Superficial lamellar keratoplasty could be assisted by the use of a microkeratome or femtosecond laser to go deeper into the original flap. Deep anterior lamellar keratoplasty and penetrating keratoplasty should be the last options. Alejandro Navas, MD, MSc Mexico City, Mexico REFERENCES 1. Sharma N, Balasubramanya R, Sinha R, Titiyal JS, Vajpayee RB. Retreatment of LASIK. J Refract Surg 2006; 22:396–401 2. Vaddavalli PK, Diakonis VF, Canto AP, Culbertson WW, Wang J, Kankariya VP, Yoo SH. Complications of femtosecond laser-assisted re-treatment for residual refractive errors after LASIK. J Refract Surg 2013; 29:577–580

J CATARACT REFRACT SURG - VOL 40, JUNE 2014

June consultation #5.

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