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46 EWInternational May 2012 International outlook Dispatch from Riyadh: Remarkable keratoconus insights are here by Matt Young EyeWorld Contributing Editor nderstanding the spectrum of keratoconus and keratectasia, the causes, risk factors, and treatment remain one of the principal challenges we face in ophthalmology. Population differ- ences in the incidence of keratoconus have long been observed. Genetic and en- vironmental factors have been suspected, however we lack the means of identifica- tion and measurement of markers for sus- ceptibility. This search continues. In the meantime, treatment options continue to evolve. The collaborative work of Wilmer Eye Institute and King Khaled Eye Special- ist Hospital in Riyadh, Saudi Arabia, is yielding new insights to serve a regional population in need as well as provide guidance for the rest of the world. U John Vukich, M.D., international editor You may be up to date on all the literature about keratoconus, but there's much more to be learned in Saudi Arabia A little more than 2 years ago, the Wilmer Eye Institute (WEI) at Johns Hopkins, Baltimore, and the King Khaled Eye Specialist Hospital (KKESH), Riyadh, Saudi Arabia, teamed up to combat eye diseases more quickly than either could working alone. Under the partnership, com- pelling research and treatment is under way that is leading to superior outcomes for patients with kerato- conus. KKESH is a promising center to work on eradicating keratoconus issues. For starters, KKESH is the largest eye hospital in the Kingdom of Saudi Arabia and one of the top- ranked medical facilities in the Mid- dle East. The hospital serves about 1,500 patients per day. Referrals come in from across Saudi Arabia, treated by a team of about 50 oph- thalmologists. But beyond KKESH's unique ability, ophthalmologists there are finding it is the perfect place to concentrate on keratoconus studies and solutions. "I have worked in different countries in the past," said Ashley Behrens, M.D., KKESH/WEI profes- sor of international ophthalmology, and executive medical director, KKESH. "I'm originally from Venezuela, and I did most of my training in that country, the U.S., and Germany. I have seen hundreds of patients from these three very dif- ferent populations, and I have never seen such a high incidence of kera- toconus in my clinic." Keratoconus, an inflammatory, progressive, and ectatic disease of the cornea, is common in Saudi Arabia and is on the rise, said Samar Al Swailem, M.D., senior consult- ant, anterior segment division, KKESH. "It is more common than what used to be the case 10 years ago," Dr. Swailem said. "The number one leading cause of corneal transplanta- tion in our population used to be corneal scarring. In the last 10 years, keratoconus has become the number Corneal topography assessment at King Khaled Eye Specialist Hospital Source: Ashley Behrens, M.D. one cause, leading to more than 70% of transplant cases." Dr. Swailem said patients as young as 12 years old are seen to have advanced keratoconus. Research is currently ongoing into this phenomenon, but Dr. Swailem believes genetic and envi- ronmental factors are at play. "We believe in our population that more than 10% of keratoconus cases are related to genes," Dr. Swailem said. There is a high rate of consanguinity in Saudi Arabia, which means genetic diseases are common. The high and increasing rate of keratoconus is probably linked to allergy as well, Dr. Swailem said. "We live in a dry and dusty environment with a high risk of allergic conjunctivitis," Dr. Swailem said. "This is an important risk factor for keratoconus." She explained that patients with allergy tend to rub their eyes chroni- cally, and rubbing the cornea is con- sidered one reason for developing ectatic disease. "It makes the cornea softer and reduces the strength of the cornea, causing it to become ectatic instead of preserving its shape," she said. Meanwhile, KKESH is looking into modalities of treatment that would arrest or reduce the progres- sion of keratoconus in the region. Conventional treatments have in- cluded contact lenses and kerato- plasty. But KKESH is doing research into corneal collagen crosslinking (CXL), which was introduced 3 years ago, and intrastromal corneal rings. In the process, important les- sons have been learned about these new treatment options. "CXL cannot be used in ad- vanced cases," Dr. Swailem said. For safety reasons and so as not to dam- age the corneal endothelium, pa- tients should have more than 400 microns of corneal thickness— which advanced cases do not have— for CXL to be performed, she said. Nonetheless, it is an important treatment option for other patients. Patient selection, therefore, is critical in treating keratoconus effectively. For patients with advanced kera- toconus, KKESH is using intrastro- mal corneal rings with good success. This modality has been found to be safer in thin corneas. It has been especially useful in Saudi Arabia, where patients have thinner corneas in general, Dr. Swailem said. Cur- rently, the center has more than 7 years of follow-up data on such cases, analyzing results on Intacs (Addition Technology, Des Plaines, Ill.) and the Keraring (Mediphacos Ltda., Brazil). KKESH ophthalmologists have found outcomes to be better with femtosecond implantation of Intacs. "There has been more improve- ment of uncorrected visual acuity and in best spectacle-corrected visual acuity," Dr. Swailem said. "There also is a higher satisfaction rate among patients, and the infection rate is much less. We believe that the use of femtosecond-assisted implan- tation of corneal rings in the popu- lation over the last 4 years has improved outcomes." Patients implanted as such had less progression of keratoconus and