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Comparison of corneal irregular astigmatism by the type of corneal regular astigmatism
Scientific Reports, 2021 We investigated the relation between corneal regular and irregular astigmatism in normal human eyes. In 951 eyes of 951 patients, corneal irregular astigmatism, such as asymmetry and higher-order irregularity components, was calculated using the Fourier ...
Yuta Ueno +5 more
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THE AXIS OF ASTIGMATISM. [PDF]
JAMA: The Journal of the American Medical Association, 1905 Twelve years ago 1 I presented some views on the axis of astigmatism. Those views consisted partly of propositions to be verified or denied by experience, partly of facts as developed in my practice. I set forth the initial proposition that the axis of astigmatism does not occur at haphazard, that there is a regularity in its occurrence in a given eye,
J. Herbert Claiborne
openalex +4 more sources
Postoperative Corneal and Surgically Induced Astigmatism following Superior Approach Manual Small Incision Cataract Surgery in Patients with Preoperative Against-the-Rule Astigmatism [PDF]
Journal of Ophthalmology, 2016 The aim of the study was to report postoperative corneal and surgically induced astigmatism (SIA) in patients with preoperative against-the-rule (ATR) astigmatism who underwent superior approach manual small incision cataract surgery (MSICS).
Edmund Arthur +6 more
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A Reciprocal Transformation for the Constant Astigmatism Equation [PDF]
SIGMA 10 (2014), 091, 20 pages, 2011 We introduce a nonlocal transformation to generate exact solutions of the constant astigmatism equation $z_{yy} + (1/z)_{xx} + 2 = 0$. The transformation is related to the special case of the famous B\"acklund transformation of the sine-Gordon equation with the B\"acklund parameter $\lambda = \pm1$. It is also a nonlocal symmetry.
Hlaváč, Adam, Marvan, Michal
arxiv +4 more sources
BMC Ophthalmology, 2020 Background China has been undergoing dramatic economic development, accompanied by increased education load on the young children. This study is to investigate the prevalence, type, severity, and associated risk factors of astigmatism in school students ...
Jianyong Wang +7 more
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Effect of congenital ptosis on astigmatism and axis length [PDF]
Guoji Yanke Zazhi, 2013 AIM: To investigate the effects of congenital ptosis degree on total astigmatism, corneal astigmatism, intraocular astigmatism and axis length, and to discuss the relation with amblyopia.
Guo-Gang Luan +6 more
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Nonlocal conservation laws of the constant astigmatism equation [PDF]
J. Geom. Phys. 113 (2017) 117-130, 2016 For the constant astigmatism equation, we construct a system of nonlocal conservation laws (an abelian covering) closed under the reciprocal transformations. We give functionally independent potentials modulo a Wronskian type relation.
Hlaváč, Adam, Marvan, Michal
arxiv +3 more sources
Scientific Reports, 2021 This study tried to compare the clinical outcomes of femtosecond laser-assisted astigmatic keratotomy (FSAK) and toric intraocular lens (IOL) implantation for astigmatism correction and identify factors affecting the efficacy of FSAK and toric IOL ...
Hoon Noh +4 more
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