EyeWorld Asia-Pacific June 2021 Issue

REFRACTIVE EWAP JUNE 2021 37 and colleagues developed an automated machine-based classifier of epithelial profiles for detecting keratoconus well before specific topography or tomographic changes. 9 “The Insight 100 incorporates our machine-based algorithm that classifies the epithelial profile as keratoconic with 95% sensitivity and 99% specificity, levels much higher than can currently be achieved by topography or tomography,” he said. “The epithelium can then be used to exclude keratoconus in cases of suspect topography, such as inferior steepening, or to confirm keratoconus in cases of equivocal topography or tomography,” 10 Dr. Reinstein continued. “Our studies on screening with epithelial profiles in the presence of inferior steepening showed that 85% of the time the inferior steepening was due to the epithelium being thicker inferiorly, and not keratoconus, allowing us to rule in cases that we would have previously rejected for corneal surgery.” Dr. Carones reiterated that he finds epithelial mapping helpful in detecting keratoconus-like patterns that are not in fact keratoconus. “Sometimes we see some sort of steepening on corneal curvature maps, and you always have to question whether this is keratoconus or something else. The epithelial map helps discriminate because if we find some sort of corneal steepening and if steepening is related to epithelial thickness, we know this is not keratoconus,” he said. Dry eye disease can also cause variability in epithelial maps, Dr. Cummings noted. “Subclinical anterior basement disorder where there are no signs of map, dot, or fingerprints can also cause variability in the epithelial profile that can be misinterpreted as keratoconus,” Dr. Reinstein said. A post-refractive surgery tool After corneal surgery, Dr. Carones said epithelial maps can provide information prior to enhancements. If, for example, there was a myopic shift post- refractive surgery, epithelial maps can help distinguish between true progression vs. thicker epithelium acting as a positive contact lens. “Sometimes it is just because the epithelium became thicker in the center compared to the mid-periphery, and removing the epithelium and doing the PRK enhancement may lead to a reepithelialization where the epithelium is not even in the center so the amount of correction used by the laser would lead to an overcorrection,” Dr. Carones said. Dr. Carones said he includes epithelial mapping assessments in all of his post-refractive surgery visits. During the early postop period, epithelial maps help him assess the healing process. If the epithelium is uneven or irregular, he said he knows healing is still taking place. Once it regularizes, the healing process is over. After several years, epithelial mapping The Next Generation NEW Pentacam ® AXL Wave The first device to combine Scheimpflug Tomography with Axial Length + Total Wavefront + Refraction + Retroillumination The new Pentacam ® AXL Wave is a reliable partner for your refractive and cataract practice, creating the best prerequisites for surgery, based on pre-op metrics, and providing post-op measurements for reliable monitoring, in just one device ! With high-end hardware and software for optimum treatment and satisfied patients, the new Pentacam ® AXL Wave makes no compromises on quality. OCULUS Asia Ltd. Hong Kong pentacam.com/axl-wave • info@oculus.hk ASCRS Eyeworld Pentacam AXL Wave 254x107.95 e 04.21.indd 1 26.04.2021 18:13:19