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331.
Does a two-year period of orthokeratology lead to changes in the endothelial morphology of children?
Purpose
To compare changes in endothelial morphology in the central and superior cornea in subjects wearing single-vision spectacles and orthokeratology lenses over two years.Methods
Endothelial images of the two locations of 99 subjects (6–12 years) from completed myopia control studies were analysed. Endothelial cell density (ECD), coefficient of variation in cell size (CV), and hexagonality (HEX) before and two years after treatment were compared between the two groups of subjects.Results
Baseline ECD and CV in the central cornea were slightly lower than those in the superior cornea, but no significant difference in HEX was found in the two corneal locations. After two years, reduction in ECD and increase in CV were only significant in the central cornea, but not in the superior cornea. Reduction in HEX was significant in both corneal locations. Subjects receiving orthokeratology had smaller reduction in ECD in the central cornea compared to the controls (orthokeratology: 56 ± 94 cells/mm2; control: 98 ± 91 cells/mm2, p = 0.024), otherwise, there were no significant differences in the changes in endothelial morphology in the two corneal locations between the two groups of subjects.Conclusions
The current study confirmed that there were differences in endothelial morphology of central and superior cornea of Chinese children aged 6–12 years. The morphological response to normal ageing differed between the two corneal locations as reduction in cell density and polymegathism were found only in the central cornea whilst pleomorphism was found in both locations. Orthokeratology lens wear had minimal effect on the developmental changes in endothelial morphology. 相似文献332.
Hannah Charlotte Byron Claudia Swain Pyry Paturi Pauline Colinet Raphaël Rullan Vesa Halava Tangui Le Bahers Mika Lastusaari 《Advanced functional materials》2023,33(42):2303398
Photochromic sodalites are considered for a plethora of possible applications, such as UV indexing and X-ray imaging, but for many of these the materials are yet to be optimized. UV indexing can be improved through incremental adjustment of the activation energy of coloration from 300 to 410 nm through replacement of sulfur with selenium. By combining this and other methods of tuning presented in the literature, the excitation threshold and photochromism color can be tuned independently of one another. The range of possible absorption maxima is expanded to 420–680 nm, or almost the entire visible spectrum. Mixing low-cost and easy-to-synthesize sodalites further broadens the possible range of colors and facilitates development of a unique sodalite mix capable of quantifying the doses of two types of UV radiation simultaneously. Finally, the response to X-rays of these highly tuned sodalites is investigated, and it is found that they can be sensitized to produce clear, high-contrast X-ray images at significantly lower doses of radiation than those required by classic photochromic sodalite, Na8(AlSiO4)6(Cl,S)2. 相似文献