低度散光的矫正。

Correction of low levels of astigmatism.

作者信息

Bullimore Mark A, Spooner Greg, Sluyterman Georg, Dishler Jon G

机构信息

From the College of Optometry (Bullimore), University of Houston, Houston, Texas, Gain Consulting Services (Spooner), San Francisco, California, and the Dishler Laser Institute (Dishler), Greenwood Village, Colorado, USA; Carl Zeiss Meditec AG (Sluyterman), Jena, Germany.

出版信息

J Cataract Refract Surg. 2015 Aug;41(8):1641-9. doi: 10.1016/j.jcrs.2014.12.060.

DOI:10.1016/j.jcrs.2014.12.060

PMID:26432121

Abstract

PURPOSE

To reevaluate the analysis of the correction of astigmatism.

SETTING

Academia, industry, and private practice.

DESIGN

Evaluation of diagnostic test or technology.

METHODS

Astigmatic refractive surgery outcomes are based on vector methods, including the correction index (also known as the correction ratio), which is the ratio of the surgically induced astigmatism to the target induced astigmatism (TIA). Mean correction indices substantially greater than 1 have been reported for astigmatic corrections less than 1.00 diopter (D) and as representing systematic overcorrection. We hypothesize that this reflects a limitation of the correction index rather than systematic flaws in treatments. The theoretical mathematic behavior of the correction index was analyzed, accounting for variability in astigmatism measurement. Then, the impact of cylinder measurement variability on the mean correction index was modeled. A Monte Carlo simulation was performed and calculated 10 000 values of correction index for various values of TIA. Finally, correction indices from published and unpublished studies of refractive lasers were compared with the simulations.

RESULTS

The mean correction index is always greater than 1 for the case of a perfect refractive correction; however, for astigmatic corrections less than 1.00 D, the mean correction index increases sharply because the measurement variability is similar in magnitude to TIA. Almost all previous studies show the predicted increase in the correction index for low astigmatic corrections.

CONCLUSION

The correction index is a useful vector-based metric for the evaluation of refractive procedures, but mean values greater than 1 should be anticipated for lower astigmatic treatments and do not necessarily represent systematic overcorrection.

FINANCIAL DISCLOSURE

Dr. Bullimore is a consultant to Alcon Surgical, Inc., Carl Zeiss Meditec AG, Digital Vision Systems, Essilor, Innovega, Inc., and Paragon Vision Sciences, Inc. Dr. Spooner is a consultant to Alcon Surgical, Inc., Carl Zeiss Meditec AG, Digital Vision Systems, Thru-Focus Optics LLC, and i2eyediagnostics, Ltd. Dr. Dishler is a consultant to Carl Zeiss Meditec AG and Revision Optics, Inc. Dr. Sluyterman is an employee of Carl Zeiss Meditec AG.

摘要

目的

重新评估散光矫正的分析。

机构

学术界、行业和私人诊所。

设计

诊断测试或技术评估。

方法

散光屈光手术结果基于矢量方法，包括矫正指数（也称为矫正率），即手术诱导散光与目标诱导散光（TIA）的比值。对于小于1.00屈光度（D）的散光矫正，已报道平均矫正指数显著大于1，这被视为系统性过矫正。我们假设这反映的是矫正指数的局限性，而非治疗中的系统性缺陷。分析了矫正指数的理论数学行为，并考虑了散光测量的变异性。然后，模拟了柱镜测量变异性对平均矫正指数的影响。进行了蒙特卡洛模拟，针对不同的TIA值计算了10000个矫正指数值。最后，将已发表和未发表的屈光激光研究中的矫正指数与模拟结果进行了比较。

结果

在完美屈光矫正的情况下，平均矫正指数始终大于1；然而，对于小于1.00 D的散光矫正，平均矫正指数会急剧增加，因为测量变异性在大小上与TIA相似。几乎所有先前的研究都显示了低散光矫正时矫正指数的预期增加。

结论

矫正指数是一种用于评估屈光手术的有用的基于矢量的指标，但对于较低散光治疗，应预期其平均值大于1，这不一定代表系统性过矫正。

财务披露

Bullimore博士是爱尔康手术公司、卡尔蔡司医疗技术股份公司、数字视觉系统公司、依视路公司、Innovega公司和帕拉贡视觉科学公司的顾问。Spooner博士是爱尔康手术公司、卡尔蔡司医疗技术股份公司、数字视觉系统公司、Thru-Focus Optics有限责任公司和i2eyediagnostics有限公司的顾问。Dishler博士是卡尔蔡司医疗技术股份公司和Revision Optics公司的顾问。Sluyterman博士是卡尔蔡司医疗技术股份公司的员工。