角膜地形图的可重复性：“角膜区域”

Repeatability of corneal topography: the "corneal field".

作者信息

Zadnik K, Friedman N E, Mutti D O

机构信息

School of Optometry, University of California, Berkeley 94720, USA.

出版信息

J Refract Surg. 1995 Mar-Apr;11(2):119-25. doi: 10.3928/1081-597X-19950301-12.

DOI:10.3928/1081-597X-19950301-12

PMID:7634141

Abstract

BACKGROUND

The purpose of this study was to determine the interoccasion repeatability of keratometry, photokeratography, and videokeratography and to describe the "corneal field," a scheme for explaining videokeratography results.

METHODS

A single examiner obtained corneal curvature measurements with a keratometer, a photokeratoscope, and the TMS-1 in 29 adult patients on two occasions.

RESULTS

Estimates for the repeatability of keratometry were +/- 0.49 and +/- 0.65 diopters (D) for the horizontal and vertical meridians respectively. The repeatability of photokeratography was +/- 0.90 and +/- 1.21 D. We presented a rational method for presenting numeric videokeratographic data by temporally and spatially averaging corneal curvature values and grouping them into 24 regions. The repeatability of videokeratography with the TMS-1 was +/- 0.50 D centrally, +/- 0.65 D paracentrally, and +/- 0.80 to +/- 1.00 D in the midperiphery.

CONCLUSIONS

Repeatability of the photokeratoscope for central measurements is considerably worse than the keratometer. The repeatability of videokeratography is worse toward the periphery. Refractive surgeons and contact lens investigators need to be aware of these limitations so that true change can be distinguished from measurement error.

摘要

背景

本研究的目的是确定角膜曲率计、光角膜照相术和视频角膜照相术的测量结果在不同测量次数之间的可重复性，并描述一种用于解释视频角膜照相术结果的“角膜区域”方案。

方法

由一名检查者使用角膜曲率计、光角膜镜和TMS-1对29名成年患者进行两次角膜曲率测量。

结果

角膜曲率计测量结果的可重复性估计值为，水平子午线方向为±0.49屈光度（D），垂直子午线方向为±0.65 D。光角膜照相术的可重复性为±0.90 D和±1.21 D。我们提出了一种合理的方法，通过对角膜曲率值进行时间和空间平均并将其分组到24个区域来呈现数字视频角膜照相术数据。使用TMS-1进行视频角膜照相术测量的可重复性为，中央区域为±0.50 D，旁中央区域为±0.65 D，中周边区域为±0.80至±1.00 D。