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Clinical Analysis of Scleral Lenses on Regular Corneas Stephanie Ramdass, OD, MS; Chad Rosen OD, FAAO; Craig Norman, FCLSA; Robert Buckingham, OD, PhD, FAAO Introduction The use of scleral lenses is becoming a mainstay for many practitioners when dealing with irregular corneas (Figure 1). Refractive error management in patients suffering from primary and secondary corneal ectasia is often most successful when the entire irregularity is vaulted over with the contact lens. In ocular surface diseases such as severe dry eye and Steven’s Johnsons Syndrome, the constant bath of liquid against the compromised corneal surface can provide significant relief of associated discomfort and painful symptoms. As this use continues to expand, we are also seeing a trend of practitioners questioning whether or not scleral lenses can/should be used on normal corneas. In subjects with normal keratometric measurements and corneal surfaces devoid of any observed pathology (Figure 2), could scleral lens wear be successfully implemented? The purpose of this study was to assess the results of vision, comfort, and fit on regular corneas in a clinical setting among a cohort of young adults. Figure 2 Figure 1 Methods Thirty-Five (35) subjects who met the Ferris State University’s Institutional Review Board approved study protocol criteria were enrolled. A minimum of four office visits were required (Figure 3). During the initial fitting visit, a diagnostic fit of both the right and left eye was carried out according to manufacturer recommended guidelines using the Valley Contax Custom Stable design. Lenses were ordered and dispensed to each subject with all instructions, solutions, and tools provided (Figure 4). Figure 3 If successful scleral lens wear remained after 1-week of daily wear up to 10 hours a day, subjects were instructed to continue with lens wear for an additional 3 weeks. Satisfaction surveys were completed by each subject at each follow-up visit. At the 1-month follow-up, scleral lenses were removed in office, and the cornea and conjunctival tissues were stained using fluorescein and lissamine green ocular stain, respectively. Figure 4 Results Seventy-seven (77) percent of subjects (age range 19 – 37 years old) achieved a logMAR visual acuity of 0.2 or better and successfully wore their scleral lenses for up to 16 hours a day. Eight (8) subjects discontinued for various reasons unrelated to adverse productrelated events. Compression of fine conjunctival vessels observed during the original fitting process (Figure 6) was a good clinical indicator that a modification of diagnostic parameters of the scleral landing zone was necessary (Chart 3). Only mild compression was observed for the majority of subjects at the end of the study period. Clinically Present Toricity On average, only one refit per eye was required before contact lens parameters were finalized. In order to obtain a successful fit, with respect to vision, fit, and comfort, modifications were effectively incorporated as recommended by consultation (Table 1). Chart 1 Figure 5 Scleral Lens Centration Figure 6 Figure 5 Chart 2 Table 1 Scleral Landing Zone To optimize visual acuity, front toric powered scleral lenses were available for order and remained stable on eye to allow for clear vision throughout wear (Figure 5). A clinically significant shift towards against-the-rule final contact lens powers was observed (Chart 1). Whether the known decentration of scleral lenses on eye due to the scleral anatomy plays a role for this observation remains under investigation by the authors. (Chart 2). Figure 7 While there was no corneal staining observed during the one month follow-up visit, mild conjunctival tissue staining was seen, greatest in the horizontal rather than vertical meridian (Figure 7). Chart 3 Discussion & Conclusion The subject demographic for the study consisted of young adults who had high visual demands at distance, intermediate, and near. All of these subjects were accustomed to excellent visual acuity. This particular scleral lens design was easily customizable to result in an over 77% success rate with respect to vision, fit and comfort of the bilaterally fit contact lenses. The majority of subjects were satisfied overall with the use scleral lens use, most Overall Subject Satisfaction Survey Chart 4 citing extra time for care and handling the modality as the main reason for any dissatisfaction (Chart 4). From this 1 month study, the authors conclude that while irregular corneas are the main platform for scleral lens use, regular eyes can benefit from the comfort and vision that these lenses provide as well. Further investigation is warranted. The authors would like to thank Valley Contax for providing an unrestricted educational grant for the completion of this study.