·AIM:To study the relationship between corneal white-to- white (WTW) distance and mesopic pupil diameter. ·METHODS:This study is composed of 30 cases that underwent photorefractive keratotomy (PRK). Pupil si...·AIM:To study the relationship between corneal white-to- white (WTW) distance and mesopic pupil diameter. ·METHODS:This study is composed of 30 cases that underwent photorefractive keratotomy (PRK). Pupil size measurements were performed with Schwind ORK wavefront analyzer in mesopic conditions. WTW distance was measured with a measuring caliper. Also, A-scan ultrasound examination was performed in all patients. The relationship among the mesopic pupil diameter and age, sex, axial length, lens thickness, anterior chamber depth(ACD), horizontal WTW distance, vertical WTW distance, spherical equivalent, and average keratometry were analyzed with univariate and multivariate regression analysis. ·RESULTS:Mean pupil diameter was (6.39±0.80)mm (range:3.70mm to 7.73mm. Horizontal WTW distance measurements were between 11.00mm and 12.50mm and mean horizontal WTW distance was (11.79±0.43)mm. On the other hand, vertical WTW distances ranged between 10.00mm and 13.00mm, and their mean was(11.42±0.72)mm. Bivariate correlation between pupil diameter and other variables showed that the axial length, ACD, spherical equivalent, and horizontal WTW distance had a moderate correlation with mesopic pupil diameter. Multiple regression analysis revealed that spherical equivalent and horizontal WTW distances were significantly associated with mesopic pupil diameter (R =0.598, R 2=0.358 P =0.02). ·CONCLUSION:This study shows that mesopic pupil diameter is closely related to horizontal WTW distance. These two factors must be taken in consideration together in preoperative ablation zone planning.展开更多
AIM:To explore the photopic pupil size behavior in myopic children undergoing overnight orthokeratology(ortho-k)over 1-year period and its effects on the axial elongation.METHODS:A total of 202 Chinese myopic children...AIM:To explore the photopic pupil size behavior in myopic children undergoing overnight orthokeratology(ortho-k)over 1-year period and its effects on the axial elongation.METHODS:A total of 202 Chinese myopic children were enrolled in this prospective clinical trial.Ninetyfive subjects in ortho-k group and eighty-eight subjects in spectacle group completed the 1-year study.Axial length(AL)was measured before enrollment and every 6mo after the start of ortho-k.The photopic pupil diameter(PPD)was determined using the Pentacam AXL and measured in an examination room with lighting of 300-310 Lx.Stepwise multiple linear regression analysis was used to identify variables contribution to axial elongation.RESULTS:Compared with spectacle group,the average 1-year axial elongation was significantly slower in the ortho-k group(0.25±0.27 vs 0.44±0.23 mm,P<0.0001).In ortho-k group,PPDs significantly decreased from 4.21±0.62 mm to 3.94±0.53 mm after 1mo of lens wear(P=0.001,Bonferroni correction)and the change lasts for 3-month visit.No significantly change during the other follow-up visits was found(P>0.05,Bonferroni correction).The 4.81 mm PPD may be a possible cutoff point in the ortho-k group.Subjects with PPD below or equal to 4.81 mm tended to have smaller axial elongation compared to subjects with PPD above 4.81 mm after 1-year period(t=-3.09,P=0.003).In ortho-k group,univariate analyses indicated that those with older age,greater degree of myopia,longer AL,smaller baseline PPD(PPDbaseline)experienced a smaller change in AL.In multivariate analyses,older age,greater AL and smaller PPDbaseline were associated with smaller increases in AL.In spectacle group,PPD tended to be stable(P>0.05,Bonferroni correction)and did not affect axial growth.CONCLUSION:PPDs experience significantly decreases at 1-month and 3-month ortho-k treatment.Children with smaller PPD tend to experience slower axial elongation and may benefit more from ortho-k.展开更多
为研究不同道路监控补光灯对驾驶员眩光的影响程度,挑选10名视力正常受试者夜晚驾车经过城市、郊区、高速3种不同环境路段,使用照度计测量不同路段补光灯及补光灯环境照度,采用Tobii Pro Glasses 2眼动仪获取眼动特征数据,分析驾驶员瞳...为研究不同道路监控补光灯对驾驶员眩光的影响程度,挑选10名视力正常受试者夜晚驾车经过城市、郊区、高速3种不同环境路段,使用照度计测量不同路段补光灯及补光灯环境照度,采用Tobii Pro Glasses 2眼动仪获取眼动特征数据,分析驾驶员瞳孔直径变化程度及瞳孔中心位移变化。研究结果表明:驾驶员在不同道路监控补光灯照明刺激下,人眼运动会发生不同程度变化。郊区道路瞳孔直径变化最大可达32%左右,是城市道路及高速道路的3倍左右。郊区道路监控补光灯照度以及补光灯环境照度差距明显,增大驾驶员暗适应时间,在3 s内瞳孔直径未能恢复正常,造成视物不清。同时在郊区道路驾驶员瞳孔中心位置偏移至视角范围为5°~220°的边缘区域远离中央窝区,造成视野模糊。研究结果可为驾驶员夜间安全驾驶提供数据支撑及应对措施。展开更多
文摘·AIM:To study the relationship between corneal white-to- white (WTW) distance and mesopic pupil diameter. ·METHODS:This study is composed of 30 cases that underwent photorefractive keratotomy (PRK). Pupil size measurements were performed with Schwind ORK wavefront analyzer in mesopic conditions. WTW distance was measured with a measuring caliper. Also, A-scan ultrasound examination was performed in all patients. The relationship among the mesopic pupil diameter and age, sex, axial length, lens thickness, anterior chamber depth(ACD), horizontal WTW distance, vertical WTW distance, spherical equivalent, and average keratometry were analyzed with univariate and multivariate regression analysis. ·RESULTS:Mean pupil diameter was (6.39±0.80)mm (range:3.70mm to 7.73mm. Horizontal WTW distance measurements were between 11.00mm and 12.50mm and mean horizontal WTW distance was (11.79±0.43)mm. On the other hand, vertical WTW distances ranged between 10.00mm and 13.00mm, and their mean was(11.42±0.72)mm. Bivariate correlation between pupil diameter and other variables showed that the axial length, ACD, spherical equivalent, and horizontal WTW distance had a moderate correlation with mesopic pupil diameter. Multiple regression analysis revealed that spherical equivalent and horizontal WTW distances were significantly associated with mesopic pupil diameter (R =0.598, R 2=0.358 P =0.02). ·CONCLUSION:This study shows that mesopic pupil diameter is closely related to horizontal WTW distance. These two factors must be taken in consideration together in preoperative ablation zone planning.
基金Supported by the Natural Science Foundation of Shanghai(No.18ZR1435700)Clinical Research Project of Shanghai Health and Family Planning Committee(No.201840199)。
文摘AIM:To explore the photopic pupil size behavior in myopic children undergoing overnight orthokeratology(ortho-k)over 1-year period and its effects on the axial elongation.METHODS:A total of 202 Chinese myopic children were enrolled in this prospective clinical trial.Ninetyfive subjects in ortho-k group and eighty-eight subjects in spectacle group completed the 1-year study.Axial length(AL)was measured before enrollment and every 6mo after the start of ortho-k.The photopic pupil diameter(PPD)was determined using the Pentacam AXL and measured in an examination room with lighting of 300-310 Lx.Stepwise multiple linear regression analysis was used to identify variables contribution to axial elongation.RESULTS:Compared with spectacle group,the average 1-year axial elongation was significantly slower in the ortho-k group(0.25±0.27 vs 0.44±0.23 mm,P<0.0001).In ortho-k group,PPDs significantly decreased from 4.21±0.62 mm to 3.94±0.53 mm after 1mo of lens wear(P=0.001,Bonferroni correction)and the change lasts for 3-month visit.No significantly change during the other follow-up visits was found(P>0.05,Bonferroni correction).The 4.81 mm PPD may be a possible cutoff point in the ortho-k group.Subjects with PPD below or equal to 4.81 mm tended to have smaller axial elongation compared to subjects with PPD above 4.81 mm after 1-year period(t=-3.09,P=0.003).In ortho-k group,univariate analyses indicated that those with older age,greater degree of myopia,longer AL,smaller baseline PPD(PPDbaseline)experienced a smaller change in AL.In multivariate analyses,older age,greater AL and smaller PPDbaseline were associated with smaller increases in AL.In spectacle group,PPD tended to be stable(P>0.05,Bonferroni correction)and did not affect axial growth.CONCLUSION:PPDs experience significantly decreases at 1-month and 3-month ortho-k treatment.Children with smaller PPD tend to experience slower axial elongation and may benefit more from ortho-k.
文摘为研究不同道路监控补光灯对驾驶员眩光的影响程度,挑选10名视力正常受试者夜晚驾车经过城市、郊区、高速3种不同环境路段,使用照度计测量不同路段补光灯及补光灯环境照度,采用Tobii Pro Glasses 2眼动仪获取眼动特征数据,分析驾驶员瞳孔直径变化程度及瞳孔中心位移变化。研究结果表明:驾驶员在不同道路监控补光灯照明刺激下,人眼运动会发生不同程度变化。郊区道路瞳孔直径变化最大可达32%左右,是城市道路及高速道路的3倍左右。郊区道路监控补光灯照度以及补光灯环境照度差距明显,增大驾驶员暗适应时间,在3 s内瞳孔直径未能恢复正常,造成视物不清。同时在郊区道路驾驶员瞳孔中心位置偏移至视角范围为5°~220°的边缘区域远离中央窝区,造成视野模糊。研究结果可为驾驶员夜间安全驾驶提供数据支撑及应对措施。