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EW CORNEA 38 August 2015 In 15–20% of cases, a corneal transplant may be required. "Remember, it never sleeps," Dr. McGhee commented about kerato- conus. "In New Zealand, we found the highest indication for any kera- toplasty is keratoconus (46%)." "Internationally, the clinical trend now is very much to pre- vent progression of the disease and largely avoid transplantation," he said. However, one of the problems with analyzing the evidence base in respect to newer treatments for keratoconus is that much of the data remain retrospective with few randomized control studies. Dr. McGhee discussed deep an- terior lamellar keratoplasty (DALK) and penetrating keratoplasty (PK) as key options for the treatment of advanced keratoconus. He also high- lighted some possible future options for the treatment of keratoconus, including the injection of cultured, healthy keratocytes into keratoconic tissue as undertaken by his laborato- ry group. In his conclusion, Dr. McGhee offered a paradigm that included conservative, intermediate, and advanced options for dealing with keratoconus. For those with sta- ble or minimal progression with a good BSCVA, spectacles or contact lenses could prove effective, with the possibility of adding crosslink- ing. The intermediate treatment options for confirmed progression of keratoconus include crosslinking with spectacles or contact lenses or possibly intrastromal segments or keratorefractive surgery. For patients with advanced keratoconus with poor BSCVA, a treatment like DALK, PK, or phaco or toric IOL may be necessary. He highlighted that a straightforward, stepladder approach should be adopted in the manage- ment of this still somewhat enigmat- ic disease. EW Editors' note: Dr. McGhee has no finan- cial interests related to his presentation. Contact information McGhee: c.mcghee@auckland.ac.nz by Ellen Stodola EyeWorld Staff Writer members of those with diagnosed keratoconus may be useful and could potentially help in halting disease progression in individuals. Studies suggest that there is a highly variable inheritance in families; the exact percentage of those who inherit the predisposition to the dis- ease remains unknown, although as many as 50% of first degree relatives may exhibit suspicious topographic features. In relation to the prognosis of keratoconus, Dr. McGhee noted that the disease usually commences in late puberty. This is often followed by gradual, rapid, or intermittent progression over 10–40 years. raphy, higher order aberrometry, biomechanical assessment, in vivo confocal microscopy, and anterior segment OCT. He said topography is a key tool that has been increasingly used for diagnosis, assessment, and follow-up of keratoconus since 1990, and a large number of topographic and tomographic diagnostic indices have evolved for early detection of keratoconus. Dr. McGhee discussed the use- fulness of screening for keratoconus. He concluded that screening of a general population is not yet fiscally viable. "It's a relatively low preva- lence disease," he said. However, targeted screening of family D uring the World Cornea Congress VII session focusing on keratoconus, ectasias, DALK, and other lamellar grafts, Charles McGhee, MD, PhD, University of Auckland, New Zealand, gave the keynote talk, titled "Treatment Par- adigms in Keratoconus." He high- lighted evidence in keratoconus that helps to guide management, current treatment paradigms, future options, and conclusions on the treatment management paradigm. Physicians have been talking about it for 250 years, but it went by many different names, he said. It was in 1844 that Pickford provided a detailed cautionary note about this poorly understood disease, howev- er it was not until 1854 that it was first fully described by Nottingham. More than 150 years later, some of the major aspects now known about keratoconus include: it is a variable, progressive corneal ectasia, it is associated with increasing irregular astigmatism, there may be scarring and hydrops, there are genetic and environmental causes, and currently there is no curative treatment. However, the exact cause of keratoconus remains unknown. The etiology is probably multifactorial. "It may be a final common pathway for a variety of different patholog- ical processes," Dr. McGhee said. Most people adhere to the concept of a 2-hit hypothesis, he said, that one underlying factor is genetic and there is a second environmental element. The estimation of the prev- alence of keratoconus varies in reported studies but is thought to be between 8.8 and 54.4 per 100,000. This variation is due to different diagnostic criteria, differing genetic predisposition, and differing expo- sure to cofactors. Physicians are increasingly aware of the many techniques available for diagnosis, Dr. McGhee said. There are long-established options for diagnosis like slit lamp keratometry, refraction, and Placido disc. However, contemporary op- tions include topography or tomog- Keratoconus prevalence, diagnosis, prognosis, and treatments Dr. McGhee speaks at World Cornea Congress VII in San Diego. Source: ASCRS

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