利用立體顯示器探討視調節微顫動與眼壓對於視覺疲勞之研究

Abstract

日常生活中使用顯示器的機會很高，不僅在工作中盯著電腦螢幕、看電視、電影等生活娛樂，也伴隨著不同類型的顯示器，只要長期使用，眼睛會產生程度不一之疲勞，進而導致眼壓的變化。本研究主要探討觀看3D影片後視覺疲勞引起之視調節微動與眼壓變化之關係。 在本研究中，受試者依據近視度數分為輕度近視(<300度)、中度近視(300~600度)以及高度近視(≧600度)，於受試前進行辨色力測驗。實驗中，利用快門式3D顯示器與偏光式3D顯示器作為播放3D影片的工具，受試者於觀看3D影片前後，使用睫狀體視調節微動分析儀記錄受試者視調節微動情形並以眼壓筆或非接觸式眼壓計量測眼壓。資料依據常態性分別以有母數或無母數分析方法來分析與比較，並探討視調節微動與眼壓之關係。 以視調節微動之高頻成分(HFC)頻譜功率為客觀指標進行視覺疲勞分析。成對資料經由檢驗，HFC的遠視標在觀看3D影片後顯著上升，受試者有視覺疲勞情形。而眼壓經由成對t檢定檢驗觀看3D影片後平均眼壓下降並達到顯著水準。實驗結果顯示受試者視覺疲勞時眼壓下降。不過在探討不同近視程度與不同辨色力的影響中，這兩個因子對於視調節微動或眼壓皆無關。 本研究已初步探討視覺疲勞與眼壓變化關係，對於視覺疲勞時眼壓下降，可能的原因為當受試者視覺疲勞時，瞳孔大小改變，造成眼球內房水變少，導致眼壓下降，不過確切原因還需經過實驗驗證。

Long-term exposure to computer displays causes visual fatigue and may result in changes in intraocular pressure (IOP). This study investigates the relationship between IOP and visual fatigue using the aids of stereoscopic videos. Study subjects were classified into three groups, according to their refractive errors: mild myopia (>-3.0 D), moderate myopia (-3.0 D to -6.0 D) and high myopia (<-6.0 D). At first, the subjects’ color discrimination was examined using the hue test. Shutter and polarizing stereoscopic displays were used for 3-D videos. Before and after the subjects watched the videos, their accommodative microfluctuations were measured with an autorefractor keratometer, and the subjects’ IOP was measured with a Tono-Pen or a non-contact tonometer. Parametric and non-parametric methods were then used to analyze depending on data normality. The Spearman’s rank correlation coefficient was finally used to find the correlation. The spectral power of the high frequency component (HFC) of accommodative microfluctuations was the main tool for analyzing visual fatigue. The results showed that the far visual targets of HFC increased significantly after watching stereoscopic videos. Paired t-test results showed that IOP decreased and reached a significant level after the experiments. Subjects’ IOP decrease when suffered from visual fatigue. However, chromatic discrimination groups and myopia groups both showed low accordance with HFC and IOP. The study first identified the relationship between visual fatigue and IOP change. The cause of IOP reduction may be the pupil size changing when subjects suffer from visual fatigue. Changed pupil size causes the aqueous humor to decrease, leading to decreased IOP.