期刊文献+
共找到2篇文章
< 1 >
每页显示 20 50 100
The art of nomograms 被引量:2
1
作者 Samuel Arba Mosquera Diego de Ortueta Shwetabh Verma 《Eye and Vision》 SCIE 2018年第1期11-23,共13页
Background:To retrospectively analyse strategies for adjusting refractive surgery plans with reference to the preoperative manifest refraction.Methods:We constructed seven nomograms based on the refractive outcomes(sp... Background:To retrospectively analyse strategies for adjusting refractive surgery plans with reference to the preoperative manifest refraction.Methods:We constructed seven nomograms based on the refractive outcomes(sphere,cylinder,axis[SCA])of 150 consecutive eyes treated with laser in situ keratomileusis for myopic astigmatism.We limited the initial data to the SCA of the manifest refraction.All nomograms were based on the strategy:if for x diopters(D)of attempted metric,y D is achieved;we can reverse this sentence and state for achieving y D of change in the metric,x D will be planned.The effects of the use of plus or minus astigmatism notation,spherical equivalent,sphere,principal meridians notation,cardinal and oblique astigmatism,and astigmatic axis were incorporated.Results:All nomograms detected subtle differences in the spherical component(p<0.0001).Nomograms 5 and 7(using power vectors)and 6(considering axis shifts)detected significant astigmatic differences(nomogram 5,p<0.001;nomogram 6,p<0.05;nomogram 7,p<0.005 for cardinal astigmatism,p=0.1 for oblique astigmatism).We observed mild clinically relevant differences(~0.5 D)in sphere or astigmatism among the nomograms;differences of~0.25 D in the proposals for sphere or cylinder were not uncommon.All nomograms suggested minor improvements versus actual observed outcomes,with no clinically relevant differences among them.Conclusions:All nomograms anticipated minor improvements versus actual observed outcomes without clinically relevant differences among them.The minimal uncertainties in determining the manifest refraction(~0.6 D)are the major limitation to improving the accuracy of refractive surgery nomograms. 展开更多
关键词 REFRACTION NOMOGRAMS Refractive outcomes SPHERE CYLINDER
原文传递
Corneal functional optical zone under monocular and binocular assessment
2
作者 Samuel Arba Mosquera Diego de Ortueta Shwetabh Verma 《Eye and Vision》 SCIE 2018年第1期24-36,共13页
Background:In this retrospective randomized case series,we compared bilateral symmetry between OD and OS eyes,intercorneal differences and Functional Optical Zone(FOZ)of the corneal aberrations.Methods:Sixty-seven nor... Background:In this retrospective randomized case series,we compared bilateral symmetry between OD and OS eyes,intercorneal differences and Functional Optical Zone(FOZ)of the corneal aberrations.Methods:Sixty-seven normal subjects(with no ocular pathology)who never had any ocular surgery were bilaterally evaluated at Augenzentrum Recklinghausen(Germany).In all cases,standard examinations and corneal wavefront topography(OPTIKON Scout)were performed.The OD/OS bilateral symmetry was evaluated for corneal wavefront aberrations,and FOZ-values were evaluated from the Root-Mean-Square(RMS)of High-Order Wavefront-Aberration(HOWAb).Moreover,correlations of FOZ,spherical equivalent(SE),astigmatism power,and cardinal and oblique astigmatism for binocular vs.monocular,and binocular vs.intercorneal differences were analyzed.Results:Mean FOZ was 6.56±1.13 mm monocularly,6.97±1.34 mm binocularly,and 7.64±1.30 mm intercorneal difference,with all strongly positively correlated,showing that the diameter of glare-free vision is larger in binocular than monocular conditions.Mean SE was 0.78±1.30 D,and the mean astigmatism power(magnitude)was 0.46±0.52 D binocularly.The corresponding monocular values for these metrics were 0.78±1.30 D and 0.53±0.53 D respectively.SE,astigmatism magnitude,cardinal astigmatism component,and FOZ showed a strong correlation and even symmetry;and oblique astigmatism component showed odd symmetry indicating Enantiomorphism between the left and right eye.Conclusions:These results confirm OD-vs.-OS bilateral symmetry(which influences binocular summation)of HOWAb,FOZ,defocus,astigmatism power,and cardinal and oblique astigmatism.Binocular Functional Optical Zone calculated from corneal wavefront aberrations can be used to optimize refractive surgery design. 展开更多
关键词 Functional optical zone Bilateral symmetry ASTIGMATISM Cardinal and oblique astigmatism BINOCULAR MONOCULAR Intercorneal differences Correlation Enantiomorphism
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部