EyeWorld Asia-Pacific December 2017 Issue

Seeing clearer – from page 31 December 2017 EWAP SECONDARY FEATURE 33 Views from Asia-Paci c Colin CHAN, MD Vision Eye Institute L3 270 Victoria Avenue, Chatswood, NSW, Australia Tel. no. +61-2-94249999 colchan@gmail.com I t is great to see crosslinking approved by the FDA in the U.S. In Australia, crosslinking has been performed routinely since 2006 and the reported experience has been overall positive. There is no age restriction in Australia and like Dr. Raizman I find the age restriction by the FDA on crosslinking to patients 14 and older somewhat perplexing. As he stated there is reasonable safety data on pediatric crosslinking 1-3 and I have regularly crosslinked patients under the age of 14. I am so impressed at how brave some of these children are as very few need a general anesthetic. Typically, I find the haze response is more pronounced in the younger age group and so I will usually do a more prolonged taper of topical steroids. I have also had to crosslink a few patients again after 10 years if they were very young to begin with. The key point Dr. Raizman states is that it is the patients below the age of 14 who need crosslinking more as it is these patients who progress more rapidly. I completely agree. This leads to the need for corneal transplantation at a younger age. I will explain this to parents who are understandably anxious about having their beloved child have a procedure at such a young age. When the prospect of a transplant in the near future is raised, I find parents very quickly choose to do the crosslinking. I have a slightly different approach to Dr. Berdahl’s with young patients. He stated that he would be inclined to crosslink young patients straight away without documenting topographic progression of the keratoconus. I have had at least 20 young patients over the past 10 years who did not progress especially if they were active eye rubbers with significant allergic disease. In these patients, I encourage avoiding eye rubbing and prescribe mast cell stabilizers such as Zaditen (ketotifen fumarate eye drops, Novartis, Basel, Switzerland) or Patanol (olopatadine HCl eye drops, Alcon, Fort Worth, Texas) to be taken routinely for 1–2 months to help break the habit. If their allergy is more severe I will refer these children to an allergist for consideration of desensitization/immunotherapy. I then watch these patients very carefully, doing topography every 3 months as I do agree that these patients can very rapidly progress, even as much as 1–2 D of cylinder every 3 months. Currently in Australia, fewcorneal specialists performcrosslinking and topographic ablation. My concern is that even with a crosslinked cornea, there would be a risk of keratoconic progression in years to come if the cornea was ablated. I look forward to seeing 5-year data on topographic ablations and crosslinking but for the moment, I am not comfortable with the concept. I note Prof. Randleman’s comments regarding accelerated crosslinking and I look forward to more data. I have been performing epi-off accelerated crosslinking with the Avedro system now for more than 2 years and have been pleased with the results. I have not had to repeat any treatments as yet. I have definitely observed a lesser degree of haze formation with the accelerated protocol compared to the standard 30-minute irradiance with the original UVX. This may mean that there is a lesser degree of crosslinking achieved but this may still be adequate given we do not know the exact amount of crosslinking necessary to stop progression of keratoconus for any given patient. Indeed, my hope is that in the future we will be able to titrate the amount of crosslinking required according to the biomechanics and age of the patient, thereby avoiding extra unnecessary crosslinking. References 1. Panos GD, Kozeis N, Balidis M, Moschos MM, Hafezi F. Collagen Cross-Linking for Paediatric Keratoconus. Open Ophthalmol J. 2017 Jul 31;11:211–216. doi: 10.2174/1874364101711010211. eCollection 2017. 2. Viswanathan D, Kumar NL, Males JJ. Outcome of corneal collagen crosslinking for progressive keratoconus in paediatric patients. Biomed Res Int. 2014;2014:140461. doi: 10.1155/2014/140461. Epub 2014 Jun 11. 3. Vinciguerra P, Albé E, Frueh BE, Trazza S, Epstein D. Two-year corneal cross- linking results in patients younger than 18 years with documented progressive keratoconus. Am J Ophthalmol. 2012 Sep;154(3):520–6. doi: 10.1016/j. ajo.2012.03.020. Epub 2012 May 24. Editors’ note: Dr. Chan declared no relevant financial interests. The treatment of myopia with CXL is for about 1 to 1.5 D, or below what is typically treated with PRK or LASIK. The use of CXL for low myopia would treat in the center of the cornea, while for presbyopia it would treat the periphery. Research presented by Europe- an ophthalmologists at European Society of Cataract & Refractive Surgeons (ESCRS) meetings last year reported positive results in small studies of PiXL for low myopia, according to reports from Avedro. Outside the U.S., there have been studies of LASIK Xtra (Ave- dro), where CXL is used in con- junction with LASIK or PRK. “There’s some evidence that it allows the treatment to be more predictable and perhaps reduce the risk of ectasia,” Dr. Rajpal said. Within Avedro’s trials, results may come soonest from the PiXL trial for low myopia followed by PiXL for presbyopia, Dr. Rajpal said. CXL and infectious keratitis There’s some buzz, mostly abroad, about the use of CXL for the treatment of bacterial, fungal, and Acanthamoeba infections. The results appear mixed so far. “Shal- lower, earlier bacterial infections appear to respond best, while fun- gal infections also appear effica- cious. There’s an uncertain impact on Acanthamoeba infections,” Dr. Randleman said. “I think the results are some- what equivocal,” Dr. Hersh said. “There are some reports that show it’s efficacious, and other reports show no difference compared to traditional therapy.” Still, he sees a lot of interest and promise in this potential use. Obtaining coverage One challenging area since the in- troduction of CXL in the U.S. has been insurance reimbursement. As Dr. Hersh pointed out, there are high costs involved with getting a procedure like CXL approved, and there’s a relatively small subset of patients who require treatment. “Unlike a drug approval that treats millions, the number of keratoco- nus and ectasia patients is sub- stantially smaller in the U.S.,” he said. He also mentioned the long 8-year period that was needed to reach FDA approval. “It’s frustrating to us as oph- thalmologists because this is very valuable to patients, and we want them to have good access,” he said. This quandary has led to the development of the Avedro Reim- bursement Customer Hub (ARCH) program. The program helps with submission to insurance and ap- peals, and it helps patients who may not be able to afford treat- ment with cost issues, Dr. Rajpal said. EWAP Editors’ note: The physicians have financial interests with Avedro. Contact information Hersh: phersh@vision-institute.com Rajpal: rrajpal@seeclearly.com Randleman: JamesBradley.Randleman@ med.usc.edu Crosslinking treatment Source (all): J. Bradley Randleman, MD