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Purpose: To evaluate the effective optical zone (the part of the ablation that receives full correction) among eyes that underwent laser epithelial keratomileusis (LASEK)/epi-LASEK treatments for myopic astigmatism.
Methods: Twenty LASEK/epi-LASEK treatments with a mean spherical equivalent refraction (SE) of -5.49±2.35 diopters (D) performed using the SCHWIND AMARIS system were retrospectively evaluated at 6-month follow-up. In all cases, pre- and postoperative corneal wavefront analyses were performed with the Keratron Scout (OPTIKON 2000). Effective optical zone values were evaluated from the changes of root-mean-square (RMS) of higher order wavefront aberration (ΔRMSho), spherical aberration (ΔSphAb), and RMS of the change of higher order wavefront aberration (RMS[ΔHOAb]). Correlations of effective optical zone with planned optical zone and SE correction were analyzed using a bilinear function as well as calculations of the isometric lines for which effective optical zone equals planned optical zone and of the nomogram planned optical zone to achieve an intended effective optical zone.
Results: At 6 months, SE was -0.05±0.43 D, with 90% of eyes within ±0.50 D. Mean higher order wavefront aberration RMS increased 0.12 μm, spherical aberration 0.09 μm, and coma 0.04 μm after treatment (6-mm diameter). Mean planned optical zone was 6.76±0.25 mm, whereas mean EOZ(ΔRMSho) was 6.74±0.66 mm (bilinear correlation P<.005), EOZ(ΔSphAb) was 6.83±0.58 mm (bilinear correlation P<.0001), and EOZ(RMS(ΔHOAb)) was 6.42±0.58 mm (significantly smaller, P<.05; bilinear correlation P<.0005).
Conclusions: The EOZ(ΔRMSho) and EOZ(ΔSphAb) were similar to the planned optical zone, whereas EOZ(RMS(ΔHOAb)) was significantly smaller. Differences between effective optical zone and planned optical zone were larger for smaller planned optical zone or larger SE corrections. Planned optical zones >6.75 mm result in effective optical zones at least as large as planned optical zones. For optical zones <6.75 mm, a nomogram should be applied.
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http://dx.doi.org/10.3928/1081597X-20100428-03 | DOI Listing |
Retina
September 2025
Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.
Purpose: To evaluate the long-term functional and anatomical outcomes in patients with tractional lamellar macular holes who were managed without surgical intervention.
Methods: 63 eyes previously diagnosed with tractional lamellar macular hole between July 1, 2009 and January 30, 2024 without any surgical interventions were enrolled. The change in best-corrected visual acuity (BCVA), lamellar hole diameter, central retinal thickness (CRT) on Optical coherence tomography (OCT), foveal avascular zone (FAZ) areas on OCT angiography, and M-chart scores between initial and final visit were assessed.
Invest Ophthalmol Vis Sci
September 2025
Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.
Purpose: The purpose of this study was to investigate the focal relationship between choroidal thickness and retinal sensitivity in myopic eyes.
Methods: Participants underwent swept-source optical coherence tomography (SS-OCT) imaging and microperimetry testing. Choroidal thicknesses were obtained by segmenting the SS-OCT scans using a deep-learning approach.
J Refract Surg
September 2025
Department of Refractive Surgery, Aier Eye Hospital, Jinan University, Guangzhou, Guangdong, China.
Purpose: To report the refractive outcome of femtosecond laser-assisted lenticule intrastromal keratoplasty (LIKE) in correcting moderate to high hyperopia. Intraoperative effective optical zone (EOZ), centration offset, and postoperative higher order aberrations (HOAs) were analyzed to better understand factors affecting postoperative outcomes.
Methods: This was a prospective, consecutive case series study of LIKE for correcting hyperopia in one department from 2018 to 2023.
J Refract Surg
September 2025
From National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, China.
Purpose: To use parametric numerical simulation to characterize and compare the differences in corneal biomechanical responses to laser in situ keratomileusis (LASIK) and keratorefractive lenticule extraction (KLEx) under various surgical settings.
Methods: The Finite Element Model was used in a parametric study to evaluate corneal biomechanical responses to LASIK and KLEx, considering variations in preoperative corneal thickness, corneal flap/cap thickness and diameter, refractive correction, and optical zone diameter. Surgery-induced stress, displacement, and interface contact pressure were compared between LASIK and KLEx using the Wilcoxon signed-rank test.
Analyst
September 2025
Ulm University, Institute of Analytical and Bioanalytical Chemistry, Albert-Einstein-Allee 11, D-89081 Ulm, Germany.
This study aims at the establishment of a universally applicable etching methodology to unveil the nanoscale crystalline structure of the matrix resin in fiber reinforced thermoplastic (FRTP) composites scanning electron microscopy (SEM). The crystalline structure hierarchically consists of crystalline texture, spherulite and lamella. The details of these structures are key parameters to understand the relationship with the mechanical properties of the material for the advancement.
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