Effect of MV-CL correcting presbyopia on contrast sensitivity
HOU Ying1,MAI Zhibin2,TANG Xiuxia2,JIANG Hongling2,WANG Xiaoying1, WANG Yang2
1.The Outpatient Department of General Hospital of Chinese People’s Armed Police Forces,Beijing 100089,China; 2.Department of Ophthalmology, Henan Provincial Corps Hospital, Chinese People’s Armed Police Forces, Zhengzhou, 450052,China
Abstract:Objective To investigate the change of distance/near vision, contrast sensitivity (CS) and the effect of glare on CS after MV-CL under mesopic and photopic conditions. Methods One eye of 35 patients weared contact lenses to improve near vision, the other eye of 12 patients with hyperopia weared contact lenses to improve distant vision. Besides, CS under the photopic and mesopic conditions was tested and the influence of glare on CS was assessed before and a month after wearing lenses; eventually these data were analyzed statistically. Results There were 89% of the patients whose naked vision was 0.8/0.33(J4) after MV-CL, and only 6% of the patients whose measured naked vision was 0.8/0.33(J4). In the photopic conditions of MV-CL, the average value of CS had a descending tendency, and especially there were statistical significance in 3.0, 12 and 18 cpd(P<0.05), so were in the mesopic conditions of MV-CL and there were statistical significance in 1.5,12 and 18 cpd(P<0.05). In the photopic conditions of MV-LV,the effect of glare on CS was obvious in 3.0,12 and 18 cpd and there were statistical significances between the two groups(P<0.05); so were in the mesopic conditions of MV-LV and there were statistical significances in 6.0 and 18 cpd(P<0.05). Conclusions Near vision can be obviously increased and presbytism can be relieved by MV-CL. The value of CS by MV-LV decreases obviously in high frequency transduction, and is effected in the mesopic conditions.Glare stimulates and decreases CS obviously in middle and high frequency.