1938
CONSULTATION SECTION
9. Kanellopoulos AJ. Long-term safety and efficacy follow-up of prophylactic higher fluence collagen cross-linking in high myopic laser-assisted in situ keratomileusis. Clin Ophthalmol 2012; 6:1125–1130. Available at: http://www.ncbi.nlm.nih.gov/pmc/ articles/PMC3413339/pdf/opth-6-1125.pdf. Accessed September 12, 2013 10. Kanellopoulos AJ, Khan J. Topography-guided hyperopic LASIK with and without high irradiance collagen cross-linking: initial comparative clinical findings in a contralateral eye study of 34 consecutive patients. J Refract Surg 2012; 28:S837–S840 11. Kanellopoulos AJ, Pamel GJ. Review of current indications for combined very high fluence collagen cross-linking and laser in situ keratomileusis surgery. Indian J Ophthalmol 2013; 61:430– 432. Available at: http://www.ncbi.nlm.nih.gov/pmc/articles/ PMC3775081/?reportZprintable. Accessed September 23, 2013
- This patient has an advanced case of ectasia after LASIK. I would perform CXL immediately and would not wait for progression. I would also combine the CXL with PRK. I would not lift the flap because it may stabilize the cornea a little. Rather, I would remove the epithelium; perform topography-guided PRK, undercorrecting by approximately 20%; soak the cornea with riboflavin for 10 minutes; and then irradiate with UV light for 30 minutes or 10 minutes, depending on the equipment used. I would limit the ablation depth to 60 mm, which means my optical zone would be approximately 5.0 mm. I would advise the patient that the chance of a good result, meaning good vision with spectacles only, is not very high but that alternatives, such as corneal transplantation, can be used later if the CXL fails. The reason I like to combine CXL and PRK is that the CXL alone will not improve vision in most cases. The downside of potentially poorer predictability of a combined versus a staged procedure is outweighed by the advantage that vision improves earlier. Michael C. Knorz, MD Mannheim, Germany
EDITOR’S COMMENT Corneal ectasia, or progressive steepening and thinning of the cornea after excimer laser ablation, is a rare but well-known cause of reduced CDVA (with spectacles). Abnormal corneal topography, young age, treatment of high myopia and the subsequent high amount of tissue ablated, low RSB thickness, and low preoperative CCT are thought to be risk factors for developing postLASIK ectasia, and surgeons often take these factors into account when evaluating refractive surgery candidates. It is a challenging situation when ectasia occurs after LASIK despite normal preoperative topography and/or a low preoperative risk. Fortunately, there is scientific evidence that we have an option to halt the progression and, in some cases, to regularize the cornea, subsequently improving visual acuity. The bulk of the respondents suggested that CXL should be performed as soon as possible as the best option to slow or halt the progression of the ectasia that is related to refractive surgery. Most respondents would also add a procedure to make the cornea more regular to improve CDVA. There is some divergence, however, in terms of which procedure to use to regularize the cornea; ICRS and topography-guided or Scheimpflug map–guided procedures are equally popular and advocated to be safe and effective if some limits are respected. Most respondents believe that the flap was thicker than expected, thus playing a significant role in the ectasia despite normal preoperative parameters.
Marcony R. Santhiago, MD, PhD Rio de Janeiro, Brazil
J CATARACT REFRACT SURG - VOL 39, DECEMBER 2013
CONSULTATION SECTION
9. Kanellopoulos AJ. Long-term safety and efficacy follow-up of prophylactic higher fluence collagen cross-linking in high myopic laser-assisted in situ keratomileusis. Clin Ophthalmol 2012; 6:1125–1130. Available at: http://www.ncbi.nlm.nih.gov/pmc/ articles/PMC3413339/pdf/opth-6-1125.pdf. Accessed September 12, 2013 10. Kanellopoulos AJ, Khan J. Topography-guided hyperopic LASIK with and without high irradiance collagen cross-linking: initial comparative clinical findings in a contralateral eye study of 34 consecutive patients. J Refract Surg 2012; 28:S837–S840 11. Kanellopoulos AJ, Pamel GJ. Review of current indications for combined very high fluence collagen cross-linking and laser in situ keratomileusis surgery. Indian J Ophthalmol 2013; 61:430– 432. Available at: http://www.ncbi.nlm.nih.gov/pmc/articles/ PMC3775081/?reportZprintable. Accessed September 23, 2013
- This patient has an advanced case of ectasia after LASIK. I would perform CXL immediately and would not wait for progression. I would also combine the CXL with PRK. I would not lift the flap because it may stabilize the cornea a little. Rather, I would remove the epithelium; perform topography-guided PRK, undercorrecting by approximately 20%; soak the cornea with riboflavin for 10 minutes; and then irradiate with UV light for 30 minutes or 10 minutes, depending on the equipment used. I would limit the ablation depth to 60 mm, which means my optical zone would be approximately 5.0 mm. I would advise the patient that the chance of a good result, meaning good vision with spectacles only, is not very high but that alternatives, such as corneal transplantation, can be used later if the CXL fails. The reason I like to combine CXL and PRK is that the CXL alone will not improve vision in most cases. The downside of potentially poorer predictability of a combined versus a staged procedure is outweighed by the advantage that vision improves earlier. Michael C. Knorz, MD Mannheim, Germany
EDITOR’S COMMENT Corneal ectasia, or progressive steepening and thinning of the cornea after excimer laser ablation, is a rare but well-known cause of reduced CDVA (with spectacles). Abnormal corneal topography, young age, treatment of high myopia and the subsequent high amount of tissue ablated, low RSB thickness, and low preoperative CCT are thought to be risk factors for developing postLASIK ectasia, and surgeons often take these factors into account when evaluating refractive surgery candidates. It is a challenging situation when ectasia occurs after LASIK despite normal preoperative topography and/or a low preoperative risk. Fortunately, there is scientific evidence that we have an option to halt the progression and, in some cases, to regularize the cornea, subsequently improving visual acuity. The bulk of the respondents suggested that CXL should be performed as soon as possible as the best option to slow or halt the progression of the ectasia that is related to refractive surgery. Most respondents would also add a procedure to make the cornea more regular to improve CDVA. There is some divergence, however, in terms of which procedure to use to regularize the cornea; ICRS and topography-guided or Scheimpflug map–guided procedures are equally popular and advocated to be safe and effective if some limits are respected. Most respondents believe that the flap was thicker than expected, thus playing a significant role in the ectasia despite normal preoperative parameters.
Marcony R. Santhiago, MD, PhD Rio de Janeiro, Brazil
J CATARACT REFRACT SURG - VOL 39, DECEMBER 2013
