環境亮度及瞳孔直徑對人眼神經對比敏感度的影響

趙冠華，曹瑞丹，張 磊，嚴偉明，陳 濤，王 斌，丁一峰，王美艷，張作明

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·臨床研究·

環境亮度及瞳孔直徑對人眼神經對比敏感度的影響

趙冠華1，曹瑞丹1，張 磊1，嚴偉明1，陳 濤1，王 斌1，丁一峰2，王美艷1，張作明1

Foundation items:The Military Logistics of Major Scientific Research Projects (No.AKJ11J002); the Military Logistics of Scientific Research Projects (No.BKJ14C008)

1Department of Clinical Aerospace Medicine, the Fourth Military Medical University, Xi’an 710032, Shaanxi Province, China;2Cadet Brigade, the Fourth Military Medical University, Xi’an 710032, Shaanxi Province, China

?METHODS: Ten healthy male volunteers (10 eyes) were recruited in this study, and the right eye was tested in this experiment. Different surround luminance levels and glare were set by Vision Monitor System to measure CSF curves of normal pupil, 3.0mm pupil and 5.0mm pupil. Modulation transfer function (MTF) curves of 3.0mm pupil and 5.0mm pupil were measured by Optical Quality Analysis System. NCSF was the ratio of CSF and MTF.

?RESULTS:NCSF and CSF curves went downward considerably and the curve waves shifted towards low spatial frequency as the surround luminance decreases. Compared with NCSF, the curve waves of CSF shifted towards lower spatial frequency. The change of CSF was affected by NCSF and MTF. When pupil diameter increases, MTF curve went downward. While the NCSF and CSF curves mounted up at low spatial frequency in the mesopic and photopic visual environment and showed downward trend at high spatial frequency in excessive bright environment or with glare. In the scotopic visual environment, the slight pupil diameter change cannot considerably affect CSF and NCSF curves.

?CONCLUSION:CSF is influenced by MTF and NCSF which reflects the function of the retina-brain neural system. The curve shape of CSF is similar to NCSF, but the curve wave is at lower spatial frequency. NCSF and CSF curves go downward as the surround luminance decreases. As the pupil diameter increases, NCSF and CSF curves mount up at low spatial frequency but show downward trend at high spatial frequency in excessive bright environment or with glare.

目的：研究環境亮度及瞳孔直徑對神經對比敏感度函數(NCSF)的影響，并與對比敏感度函數(CSF)相比較。

方法：招募健康男性志愿者10名10眼作為受試者，以右眼為測試眼，利用視覺監視系統設置不同環境亮度并附加眩光，測量自然、3.0mm和5.0mm瞳孔時的CSF；利用視覺質量分析儀測量3.0mm和5.0mm瞳孔時的調制傳遞函數(MTF)，根據CSF與MTF的比值求得NCSF。

結果：NCSF和CSF隨環境亮度降低曲線整體下移，波峰向低頻區移動，CSF更偏向低頻區。CSF變化受NCSF和MTF共同作用，瞳孔開大，MTF下降，在明視覺環境和中間視覺環境中，NCSF和CSF上升，主要上升區為中低頻區；當亮度較高或存在眩光源時，NCSF和CSF在中低頻區上升不明顯，在高頻區有下降的趨勢；在暗視覺環境中，小范圍的瞳孔波動對NCSF和CSF沒有顯著影響。

結論:NCSF能夠反映視覺神經系統的功能，與MTF共同決定CSF。CSF曲線形狀與NCSF相近，波峰更偏向低頻區。環境亮度降低會使NCSF下降，CSF隨之下降；瞳孔開大會使NCSF在中低頻區上升，CSF隨之上升，而環境較亮或存在眩光源時，NCSF和CSF在高頻區都有下降的趨勢。

對比敏感度；神經對比敏感度；亮度；瞳孔

引用：趙冠華，曹瑞丹，張磊，等.環境亮度及瞳孔直徑對人眼神經對比敏感度的影響.國際眼科雜志2016;16(12):2279-2284

0引言

對比敏感度函數(contrast sensitivity function，CSF)是檢查視覺功能的常用方法，反映了人眼在不同空間頻率上的對比敏感特征，與視敏度相比，能夠更好地反映視覺質量[1]。……