AIM： To explore the effect of the posterior astigmatism on total corneal astigmatism and evaluate the error caused by substituting the corneal astigmatism of the simulated keratometriy （simulated K） for the total c...AIM： To explore the effect of the posterior astigmatism on total corneal astigmatism and evaluate the error caused by substituting the corneal astigmatism of the simulated keratometriy （simulated K） for the total corneal astigmatism in age-related cataract patients. METHODS： A total of 211 eyes with age-related cataract from 164 patients （mean age： 66.8±9.0y, range： 45-83y） were examined using a multi-colored spot reflection topographer, and the total corneal astigmatism was measured. The power vector components J0 and J45 were analyzed. Correlations between the magnitude difference of the simulated K and total cornea astigmatism （magnitude differenceSimK-Tca）, anterior J0, and absolute meridian difference （AMD） between the anterior and posterior astigmatisms were calculated. To compare the astigmatism of the simulated K and total cornea both in magnitude and axial orientation, we drew double-angle plots and calculated the vector difference between the two measures using vector analysis. A corrective regression formula was used to adjust the magnitude of the simulated K astigmatism to approach that of the total cornea. RESULTS： The magnitude differenceSimK-Tca was positively correlated with the anterior corneal J0 （Spearman’s rho= 0.539; P〈0.001） and negatively correlated with the AMDR （Spearman’s rho=-0.875, P〈0.001）. When the anterior J0 value was larger than 1.3 D or smaller than -0.8 D, the errors caused by determining the total corneal astigmatism with the karatometric calculation tended to be greater than 0.25 D. An underestimation by 16% was observed for against the rule （ATR） astigmatism and an overestimation by 9% was observed for with the rule （WTR） astigmatism when ignoring the posterior measurements. CONCLUSION： Posterior corneal astigmatism should be valued for more precise corneal astigmatism management, especially for higher ATR astigmatism of the anterior corneal surface. We suggest a 9% reduction in the magnitude of the simulated K in eyes with WTR astigmatism, and a 16% addition of the magnitude of the simulated K in eyes with ATR astigmatism.展开更多
Background:In recent years posterior corneal astigmatism and its effect on total corneal astigmatism has been studied,with research showing that this can impact total astigmatism.This study aims to ascertain if there ...Background:In recent years posterior corneal astigmatism and its effect on total corneal astigmatism has been studied,with research showing that this can impact total astigmatism.This study aims to ascertain if there is significant change in the posterior corneal astigmatism after cataract surgery and its impact on the total astigmatism.Methods:Analysis of 76 eyes that underwent cataract surgery with monofocal intraocular lens implantation.Corneal topography was performed with Pentacam(OCULUS®)pre-and post-operatively.Total corneal astigmatism was calculated with the algorithm of vergence tracing.We compared preoperative and postoperative changes in the magnitude and axis differences of anterior corneal curvature astigmatism,posterior corneal curvature astigmatism and the calculated total corneal astigmatism.We calculated the correlation between the total preoperative astigmatism and the difference between total corneal astigmatism and anterior corneal astigmatism.Results:The mean preoperative and postoperative posterior astigmatism was 0.31±0.02 D,showing no significant differences before and after surgery(P=0.989).Statistically significant differences between the calculated total corneal astigmatism and anterior corneal astigmatism were registered preoperatively and postoperatively in the with-the-rule anterior(WTR)corneal astigmatism(P=0.004,P<0.0001);against-the-rule(ATR)anterior corneal astigmatism(P<0.0001,P<0.0001)and in the oblique(P=0.026,P=0.019)subgroups.The posterior corneal astigmatism and the total corneal astigmatism correlated positively with the differences between the total corneal and anterior corneal astigmatism(R=0.378,P=0.001).Conclusions:There were statistically significant differences between the magnitude of the total astigmatism and anterior corneal astigmatism,underlining the impact of posterior corneal astigmatism.A positive correlation between the preoperative posterior astigmatism and the difference between the total corneal and the anterior corneal astigmatism suggests a specially relevant role of posterior corneal astigmatism when evaluating patients with higher degrees of astigmatism.展开更多
目的:比较MyoRing植入前后圆锥角膜(KCN)患者角膜前后表面散光和全屈光散光。方法:历史队列研究。比较植入360度全环植入物(MyoRing)的KCN患者的术前和术后全屈光、角膜前后表面散光,术后3、6、9、12 mo连续随访四次。结果:共纳入KCN患...目的:比较MyoRing植入前后圆锥角膜(KCN)患者角膜前后表面散光和全屈光散光。方法:历史队列研究。比较植入360度全环植入物(MyoRing)的KCN患者的术前和术后全屈光、角膜前后表面散光,术后3、6、9、12 mo连续随访四次。结果:共纳入KCN患者79例85眼,其中男43例,女36例,平均年龄29±7.41(17-48)岁。随访期间,全屈光散光、角膜前后表面散光呈减少趋势。MyoRing植入后12 mo,总屈光散光测量值显著下降2.09 D (4.27±3.15 vs2.18±1.63 D,P<0.001)。此外,术后测量显示,角膜前表面和后表面散光分别改善约3.20 D和0.59 D[6.40±1.90 vs 3.20±1.75 D(P<0.001)和1.30±0.55 vs 0.71±0.35(P<0.001)]结论:MyoRing植入可显著改善散光参数,包括全屈光散光以及角膜前后表面散光。展开更多
目的:评价先天性上睑下垂严重程度与眼总散光、角膜散光和眼内散光的关系及其对眼轴长的影响,并探究与弱视发生之间的关系。方法:先天性上睑下垂患者50例100眼,按正常、轻、中、重度下垂分列Ⅰ,Ⅱ,Ⅲ,Ⅳ组,Ⅰ:33眼;Ⅱ:20眼;Ⅲ:17眼;Ⅳ:3...目的:评价先天性上睑下垂严重程度与眼总散光、角膜散光和眼内散光的关系及其对眼轴长的影响,并探究与弱视发生之间的关系。方法:先天性上睑下垂患者50例100眼,按正常、轻、中、重度下垂分列Ⅰ,Ⅱ,Ⅲ,Ⅳ组,Ⅰ:33眼;Ⅱ:20眼;Ⅲ:17眼;Ⅳ:30眼;首先进行规范的医学验光,以其散光绝对值为眼球总散光值;接着角膜地形图仪测量双眼角膜地形至少3次,取结果最好者记录角膜散光值;按公式:眼内散光=总散光-角膜散光,记录眼内散光。最后A超测量双眼轴长各5次,取其平均值。结果:总散光,角膜散光总体比较有显著差异(P=0.000,0.002<0.05),且与上睑下垂严重呈一定正相关(Spearman r s=0.514,0.721,P均<0.05);但角膜散光轴向、眼轴长度、眼内散光总体比较统计学无显著性差异(P均>0.05),其中散光轴向、眼内散光与上睑下垂严重程度亦无明显相关性。结论:先天性上睑下垂对眼散光的影响主要是通过角膜散光发生,其散光的严重程度与上睑下垂严重程度相关,但是对眼轴长不产生明显影响。弱视在重度上睑下垂眼更加常见,高的角膜散光与其有关,且多为中度的顺规散光。展开更多
基金Supported by the National Natural Science Foundation of China(No.81670837)the Scientific and Technological Project of Tianjin Health Bureau(No.2015KY38)
文摘AIM： To explore the effect of the posterior astigmatism on total corneal astigmatism and evaluate the error caused by substituting the corneal astigmatism of the simulated keratometriy （simulated K） for the total corneal astigmatism in age-related cataract patients. METHODS： A total of 211 eyes with age-related cataract from 164 patients （mean age： 66.8±9.0y, range： 45-83y） were examined using a multi-colored spot reflection topographer, and the total corneal astigmatism was measured. The power vector components J0 and J45 were analyzed. Correlations between the magnitude difference of the simulated K and total cornea astigmatism （magnitude differenceSimK-Tca）, anterior J0, and absolute meridian difference （AMD） between the anterior and posterior astigmatisms were calculated. To compare the astigmatism of the simulated K and total cornea both in magnitude and axial orientation, we drew double-angle plots and calculated the vector difference between the two measures using vector analysis. A corrective regression formula was used to adjust the magnitude of the simulated K astigmatism to approach that of the total cornea. RESULTS： The magnitude differenceSimK-Tca was positively correlated with the anterior corneal J0 （Spearman’s rho= 0.539; P〈0.001） and negatively correlated with the AMDR （Spearman’s rho=-0.875, P〈0.001）. When the anterior J0 value was larger than 1.3 D or smaller than -0.8 D, the errors caused by determining the total corneal astigmatism with the karatometric calculation tended to be greater than 0.25 D. An underestimation by 16% was observed for against the rule （ATR） astigmatism and an overestimation by 9% was observed for with the rule （WTR） astigmatism when ignoring the posterior measurements. CONCLUSION： Posterior corneal astigmatism should be valued for more precise corneal astigmatism management, especially for higher ATR astigmatism of the anterior corneal surface. We suggest a 9% reduction in the magnitude of the simulated K in eyes with WTR astigmatism, and a 16% addition of the magnitude of the simulated K in eyes with ATR astigmatism.
文摘Background:In recent years posterior corneal astigmatism and its effect on total corneal astigmatism has been studied,with research showing that this can impact total astigmatism.This study aims to ascertain if there is significant change in the posterior corneal astigmatism after cataract surgery and its impact on the total astigmatism.Methods:Analysis of 76 eyes that underwent cataract surgery with monofocal intraocular lens implantation.Corneal topography was performed with Pentacam(OCULUS®)pre-and post-operatively.Total corneal astigmatism was calculated with the algorithm of vergence tracing.We compared preoperative and postoperative changes in the magnitude and axis differences of anterior corneal curvature astigmatism,posterior corneal curvature astigmatism and the calculated total corneal astigmatism.We calculated the correlation between the total preoperative astigmatism and the difference between total corneal astigmatism and anterior corneal astigmatism.Results:The mean preoperative and postoperative posterior astigmatism was 0.31±0.02 D,showing no significant differences before and after surgery(P=0.989).Statistically significant differences between the calculated total corneal astigmatism and anterior corneal astigmatism were registered preoperatively and postoperatively in the with-the-rule anterior(WTR)corneal astigmatism(P=0.004,P<0.0001);against-the-rule(ATR)anterior corneal astigmatism(P<0.0001,P<0.0001)and in the oblique(P=0.026,P=0.019)subgroups.The posterior corneal astigmatism and the total corneal astigmatism correlated positively with the differences between the total corneal and anterior corneal astigmatism(R=0.378,P=0.001).Conclusions:There were statistically significant differences between the magnitude of the total astigmatism and anterior corneal astigmatism,underlining the impact of posterior corneal astigmatism.A positive correlation between the preoperative posterior astigmatism and the difference between the total corneal and the anterior corneal astigmatism suggests a specially relevant role of posterior corneal astigmatism when evaluating patients with higher degrees of astigmatism.
文摘目的:比较MyoRing植入前后圆锥角膜(KCN)患者角膜前后表面散光和全屈光散光。方法:历史队列研究。比较植入360度全环植入物(MyoRing)的KCN患者的术前和术后全屈光、角膜前后表面散光,术后3、6、9、12 mo连续随访四次。结果:共纳入KCN患者79例85眼,其中男43例,女36例,平均年龄29±7.41(17-48)岁。随访期间,全屈光散光、角膜前后表面散光呈减少趋势。MyoRing植入后12 mo,总屈光散光测量值显著下降2.09 D (4.27±3.15 vs2.18±1.63 D,P<0.001)。此外,术后测量显示,角膜前表面和后表面散光分别改善约3.20 D和0.59 D[6.40±1.90 vs 3.20±1.75 D(P<0.001)和1.30±0.55 vs 0.71±0.35(P<0.001)]结论:MyoRing植入可显著改善散光参数,包括全屈光散光以及角膜前后表面散光。
文摘目的:评价先天性上睑下垂严重程度与眼总散光、角膜散光和眼内散光的关系及其对眼轴长的影响,并探究与弱视发生之间的关系。方法:先天性上睑下垂患者50例100眼,按正常、轻、中、重度下垂分列Ⅰ,Ⅱ,Ⅲ,Ⅳ组,Ⅰ:33眼;Ⅱ:20眼;Ⅲ:17眼;Ⅳ:30眼;首先进行规范的医学验光,以其散光绝对值为眼球总散光值;接着角膜地形图仪测量双眼角膜地形至少3次,取结果最好者记录角膜散光值;按公式:眼内散光=总散光-角膜散光,记录眼内散光。最后A超测量双眼轴长各5次,取其平均值。结果:总散光,角膜散光总体比较有显著差异(P=0.000,0.002<0.05),且与上睑下垂严重呈一定正相关(Spearman r s=0.514,0.721,P均<0.05);但角膜散光轴向、眼轴长度、眼内散光总体比较统计学无显著性差异(P均>0.05),其中散光轴向、眼内散光与上睑下垂严重程度亦无明显相关性。结论:先天性上睑下垂对眼散光的影响主要是通过角膜散光发生,其散光的严重程度与上睑下垂严重程度相关,但是对眼轴长不产生明显影响。弱视在重度上睑下垂眼更加常见,高的角膜散光与其有关,且多为中度的顺规散光。
