CONSULTATION SECTION

1053

3. Settas G, Settas C, Minos E, Yeung IYL. Photorefractive keratectomy (PRK) versus laser assisted in situ keratomileusis (LASIK) for hyperopia correction. Cochrane Database Syst Rev(2):CD007112 4. Shammas HJ, Shammas MC, Hill WE. Intraocular lens power calculation in eyes with previous hyperopic laser in situ keratomileusis. J Cataract Refract Surg 2013; 39:739–744 5. Reinstein DZ, Archer TJ, Gobbe M. Refractive and topographic errors in topography-guided ablation produced by epithelial compensation predicted by 3D Artemis VHF digital ultrasound stromal and epithelial thickness mapping. J Refract Surg 2012; 28:657–663

contact lenses to give the patient better optical quality. A surgical treatment would be topography guided. A topography-guided treatment would probably be the best way to reestablish the corneal curvature and restore visual quality if it is possible to proceed with this treatment while respecting safety limits. Newton Kara-Junior, MD, PhD S~ao Paulo, Brazil

- I would have first approached this case with flap relifting. Laser in situ keratomileusis flaps created with a mechanical microkeratome are usually easy to lift, even years after the original surgery. For this patient, this would have been the best option with the best outcomes. I would not consider a new side cut with a femtosecond laser. First, it is difficult to determine an adequate diameter for the new side cut in a hyperopic retreatment. Second, this approach is not free of complications because slivers of tissue can be created and the same complication might occur. If it were a myopic case in which a smaller diameter side cut were possible, this would have been my first option. If flap lift were not possible, I would have treated with surface ablation and MMC 0.02% for 40 seconds. Refractive lens exchange would have been another reasonable option in terms of visual acuity results. In this case I would have chosen a standard spherical monofocal IOL or spherical aberration–neutral IOL to counterbalance the spherical aberration of the cornea after the hyperopic treatment. After the unsuccessful enhancement, I would recommend patience because the epithelium will heal and help make the corneal surface more regular. Before considering surgery, I would prescribe RGP

- This shows the need for case-by-case decisions regarding the type of refractive procedure to use. Because the patient was a 47 year old with presbyopic hyperopia at presentation, our option would have been RLE. We would implant a monofocal IOL to avoid further issues with contrast sensitivity, glare, and haloes in this already complicated eye. A spherical aberration– neutral or spherical IOL would be preferred. We would try to convince the patient to have RLE; if she adamantly declined, the next safer option would be advanced surface ablation, despite the higher incidence of regression. A larger treatment zone with a transition zone extending up to 9.5 mm often prevents regression that may otherwise occur secondary to sudden transitions between ablated and unablated corneas. Newer machines and algorithms with topography- and wavefront-guided treatments offer good outcomes for low to moderate hyperopia (!+5.00 D). With hyperopic LASIK and advanced surface ablation, care must be taken to avoid small optical zones and decentration, which cause loss of CDVA. With enhancements, it is necessary to avoid issues that make the situation worse. A decentered primary ablation can further worsen the situation. Larger flaps, even up to 10.0 mm, are recommended for hyperopic LASIK, although these may be difficult to create in small eyes. The smaller 8.5 mm flap used in this case

Figure 4. A: Similar case in which a thinner femtosecond laser–created flap was cut in a 7-year-old microkeratome flap. This shows the femtosecond flap being dissected. B: The posterior part of the old flap was accidentally dissected while trying to lift the flap from the opposite side. C: The posterior portion of the old flap was carefully and gently laid back and excimer laser ablation performed. The final UDVA was 20/20 3. J CATARACT REFRACT SURG - VOL 40, JUNE 2014

June consultation #7.

June consultation #7. - PDF Download Free
394KB Sizes 2 Downloads 3 Views