Preliminary Results of Changes in Refraction and Corneal Curvature Caused By+Gz Acceleration in Patients after Orthokeratology

經角膜塑型術後之配戴者在經高G力之後屈光及角膜弧度的變化：初報

梁知本(Jy-Been Liang) ； 陳建同(Jiann-Torng Chen) ； 劉峻正(Chun-Cheng Liu)

《中華民國眼科醫學會雜誌》 49卷1期 (2010/03) Pp. 17-24

https://doi.org/10.30048/ACTASOS.201003.0003

摘要

目的：探討在施行角膜塑型術之後，在經高G力離心下之視力、屈光度及角膜弧度的改變。
方法：5位年齡平均為25.3歲之年輕男性在配戴夜戴型角膜塑型鏡片2週後接受人體離心機之訓練，分別記錄其在離0前與後1分鐘及10分鐘後之視力、屈光度及角膜弧度之改變，同時與對照組比較差異性。
結果：實驗組的視力，在經高G力後均維持穩定，屈光度在離心1分鐘有增加但10分鐘後復原；在離心後1分鐘、10分鐘均有角膜厚度變薄及前角膜屈度增加現象。在對照組方面，屈光度在離心1分鐘時有顯著減少但在離心後10分鐘恢復，角膜厚度在離心後1分鐘及10分鐘後均減少；同時在前角膜屈度方面在離心後1分鍾有增加，離已後10分鐘回復。
結論：視力在離心後角膜弧度及屈光方面有改變下仍維持穩定，屈光度與前角膜弧度在實驗及控制組的差別，可能與角膜塑型鏡片造成角膜中心變平有關。

並列摘要

Purpose: The aim of this study was to investigate the changes in visual acuity, refraction, and corneal curvature caused by sustained+Gz acceleration of patients in a human centrifuge after overnight orthokeratology.
Methods: Five healthy men training to be aviation doctors, aged 25-26 years (mean=25.3 years), received overnight orthokeratology for two weeks. The human centrifuge at the Aviation Physiology Research Laboratory in Tainan, Taiwan, was used to expose the subjects to various acceleration profiles. Each subject experienced three centrifuge runs. Visual acuity, refraction, and corneal topography were measured before, and 1 min and 10 min after acceleration. We compared the study group findings with those of a control group of 13 subjects who had not undergone orthokeratology but experienced the same acceleration procedure.
Results: In the orthokeratology group, nine eyes of five subjects completed the study. One eye was excluded because of keratitis. Visual acuity remained stable after human centrifugation. Refraction increased significantly at 1 min, but recovered at 10 min after centrifugation. There was a significant decrease in corneal thickness and a significant increase in anterior curvature at 1 min and 10 min after centrifugation. In the control group, best-corrected visual acuity was increased at 1 min and 10 min after centrifugation. Myopic shift was noted significantly at 1 min, but increased at 10 min after centrifugation. There was a significant decrease in corneal thickness and a significant increase in anterior curvature, at 1 min but this recovered 10 min after centrifugation.
Conclusion: Visual acuity is stable, although some corneal topographic and refractive parameters change after centrifugation. Differences in the changes in refraction and anterior curvature between the orthokeratology and control groups may be due to the oblate shape of the cornea produced by the orthokeratology lens.

並列關鍵字

corneal curvature ； corneal topography ； Gz acceleration ； human Centrifuge