Purpose To evaluate the effect of the optical zone diameter (OZ) in orthokeratology contact lenses regarding the topographical profile in patients with high myopia (−4.00 D to −7.00 D) and to study its effect over the visual quality. Materials and Methods Twelve patients (18 eyes) were fitted with overnight orthokeratology (OrthoK) with a randomized 6 mm or 5 mm OZ lens worn for 2 weeks, followed by a 2-week washout period, between both designs. Keratometry (K) readings, optical zone treatment diameter (OZT), peripheral ring width (PRW), higher-order aberrations (HOA), high (HC) and low contrast (LC) visual acuity, and subjective vision and comfort were measured at baseline and after 2 weeks of OrthoK lens wear of each contact lens. Results No significant differences were found between any measurements for the same subject at both baselines (p value > 0.05). There was no difference between OZ lens designs found in refraction, subjective vision or comfort, and HC and LC visual acuity. Contrast sensitivity was decreased in the 5 mm OZ lens design compared with 6 mm OZ design (p-value < 0.05). 5 mm OZ design provoked a greater flattening, more powerful midperipheral ring and 4th-order corneal and total spherical aberration than the 6 mm OZ design, being statistically significant after 7 days, for corneal aberration, and 15 days, for corneal and total, of wearing the lens (p-value < 0.05). The OZT obtained were 2.8 ± 0.2 mm and 3.1 ± 0.1 mm for 5 mm and 6 mm OZ design, respectively (p-value < 0.05). Regarding PRW, the 5 mm OZ design had a wider ring width in both the nasal and temporal zones (p-value < 0.05). Conclusions A smaller diameter optical zone (5 mm) in orthokeratology lenses produces a smaller treatment area and a larger and more powerful midperipheral ring, increasing the 4th-order spherical aberration that affects only the contrast sensitivity but without differences in visual acuity and subjective vision compared with a larger OZ diameter (6 mm).

Purpose: To analyse long-term efficacy, safety, visual and refractive stability and physiological changes of Artiflex Myopia and Toric phakic intraocular lenses (pIOL) separately throughout an 8-year follow-up. Design: Retrospective cohort study. Methods: A total of 67 eyes of 37 patients underwent Artiflex Myopia (47 eyes) or Artiflex Toric (20 eyes) implantation for correcting myopia and/or astigmatism. Follow-up evaluations were performed 1, 3, 5 and 8 years after surgery. Preoperative and postoperative data included corrected (CDVA) and uncorrected distance visual acuity (UDVA), manifest refraction, endothelial cell density (ECD) and intraocular pressure (IOP) assessments. Efficacy and safety indexes were analysed. The vectorial analysis was performed using the Thibos method. Results: Mean CDVA and UDVA of both pIOLs significantly improved from preoperative to 1 year after implantation, and then it remained stable over the 8-year follow-up. The efficacy and safety indexes after 8 years were 0.94 ± 0.16 and 1.07 ± 0.18 for Artiflex Myopia and 1.00 ± 0.11 and 1.10 ± 0.15 for Artiflex Toric, respectively. The spherical equivalent (SE) significantly improved after surgery. J0, J45 and SE refractive components showed no changes between postoperative visits. A total ECD loss of 4.8% ( p < 0.001) and 10.4% ( p = 0.005) was found after 8 years for Artiflex Myopia and Toric, respectively. Conclusions: Artiflex Myopia and Toric pIOLs are a safe, efficient and predictable option for the correction of myopia and/or astigmatism. The vectorial analysis showed excellent rotation stability for the toric version.

46Objective: to assess the intra-rater repeatability of the measurements of tear meniscus 47 height (TMH), noninvasive Keratograph tear breakup time (NIKBUTs) and ocular redness 48 measurements obtained with the Keratograph 5M (K5M) in a sample of soft silicone 49 hydrogel CL wearers over 15 days. 50 Methods: prospective study over two consecutive weeks. Three measurements of TMH, 51 NIKBUTs (NIKBUT-first and NIKBUT-average) and ocular redness were obtained in different 52 sessions; the first day (baseline, at 8 hours of wear, and after lens removal) and the last day 53 of wear -15th day (at 8 hours of wear and after lens removal). The repeatability of 54 measurements were assessed by two intraclass correlation coefficient (ICC) forms; single 55 measurement [ICC (2,1)] and multiple measurements (k=3) [ICC (2, k)]. 56 Results: The repeatability of baseline TMH [ICC (2,1) >0.90 ; CR=0.06 mm] and after and 57 during CL wear [ICC (2,k) >0.90 ; CR≤0.07 mm] were excellent. The repeatability of baseline 58 NIKBUT-average [ICC (2,k) =0.89 (0.82 to 0.93) ; CR=6.07 sc] was maintained after CL 59 removal, but was poorer during CL wear. The repeatability of baseline NIKBUT-first [ICC (2,k) 60 =0.80 (0.69 to 0.87) ; CR=8.74 sc] was maintained after CL removal and during CL wear at 61 moderate-good level. 62 Conclusions: Intra-rater repeatability of TMH, NIKBUTs and ocular redness performed by 63 K5M after CL wear remain stable when three measurements are performed. However, intra-64 rater repeatability during CL wear decreased only for NIKBUT average and was not affected 65 by time of use (15 days).66 67