Eyeworld

EW CORNEA 122 October 2015 by Ellen Stodola EyeWorld Staff Writer The term "forme fruste" is used to describe an incomplete form of the disease, which may or may not progress to a clinical disease status. Although Dr. Ambrósio recognizes the value of this term, he said that it's often confusing, as it is some- times used to describe "suspicious findings" on corneal topography. The suspicious findings on corneal topography may represent a vari- ation of normality, and some of these cases may be good candidates for LASIK, as there are many cases reported with long-term follow-up, he said. "The advent of refractive corneal surgery determined the need to evolve on our diagnostic capabilities," Dr. Ambrósio said. When evaluating a candidate for laser vision correction, the pres- ence of mild (subclinical) disease is known to be the main risk factor for progressive iatrogenic keratectasia. "However, the confusion, also found in the literature, is that mild (sub- clinical) disease refers to the same as mild topographic irregularity." This, he said, is not correct because there are cases with mild disease with normal front surface curvature. "The best example is the group of eyes with normal topography from patients with clinical keratoconus in the fellow eye," Dr. Ambrósio said. "Interestingly, Amsler described such cases as forme fruste, but he used photokeratoscopy imaging without computerized analysis." When staging the disease, Dr. Ambrósio sees 2 different problems. The first is in the characterization of ectasia progression and the second is in determining the severity of the disease to determine the proper therapeutic strategy. New terms Dr. Ambrósio shared terms that he thinks will improve the vocabulary and ability to discuss keratoconus and other ectasias. First, he said he likes the concept of "ectasia suscep- tibility." "It refers to the character- istics of the cornea that will deter- mine its resiliency to trauma and other factors, such as laser surgery," he said. "In fact, every cornea may F ollowing the World Cornea Congress VII in San Diego, Renato Ambrósio Jr., MD, PhD, associate professor, Pontifical Catholic Uni- versity, Rio de Janeiro, and Federal University of São Paulo, spoke about his presentation at the meeting, commenting on the diagnosis of keratoconus and ectasia and some of the terms that need to be discussed when dealing with the disease. Problems in the current description and staging of keratoconus Keratoconus is the most common ectatic disease of the cornea, Dr. Ambrósio said. "As any disease, there is a 'pre-clinical' phase in which there are no symptoms or signs," he said. "Typically, in such mild cases, biomicroscopy is with- in normal limits and the corrected visual acuity is 20/20 or better." Keratoconus terminology and differential diagnosis Example of a susceptible cornea that developed ectasia after LASIK. Note the normal curvature map, with 0.6 D of inferior steepening, but with abnormal tomographic parameters. Source: Renato Ambrósio Jr., MD, PhD Las Vegas FUN FACT A 1910 law made it illegal to gamble in Las Vegas. The Nevada Legislature later approved a legalized gambling bill in 1931. Source: Las Vegas Convention and Visitors Authority

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