AIM：To assess the effects of upper lid blepharoplasty on visual quality.METHODS：Seventy-three eyelids of 39 patients were subjected to upper lid blepharoplasty.Pre- and postoperative contrast sensitivity,visual acui...AIM：To assess the effects of upper lid blepharoplasty on visual quality.METHODS：Seventy-three eyelids of 39 patients were subjected to upper lid blepharoplasty.Pre- and postoperative contrast sensitivity,visual acuity,vertical palpebral aperture and the degree of lash ptosis were measured.RESULTS：The mean log contrast sensitivities under photopic（P =0.017） and scotopic conditions（P =0.009）were improved after surgery,and these differences were significant.The degree of lash ptosis was also decreased after blepharoplasty（P〈0.001）.CONCLUSION：In our study,a significant increase in contrast sensitivity was found after surgery.These results suggest that upper lid blepharoplasty can be helpful for improving visual quality.展开更多
Most of Image Quality Assessment (IQA) metrics consist of two processes. In the first process, quality map of image is measured locally. In the second process, the last quality score is converted from the quality map ...Most of Image Quality Assessment (IQA) metrics consist of two processes. In the first process, quality map of image is measured locally. In the second process, the last quality score is converted from the quality map by using the pooling strategy. The first process had been made effective and significant progresses, while the second process was always done in simple ways. In the second process of the pooling strategy, the optimal perceptual pooling weights should be determined and computed according to Human Visual System (HVS). Thus, a reliable spatial pooling mathematical model based on HVS is an important issue worthy of study. In this paper, a new Visual Perceptual Pooling Strategy (VPPS) for IQA is presented based on contrast sensitivity and luminance sensitivity of HVS. Experimental results with the LIVE database show that the visual perceptual weights, obtained by the proposed pooling strategy, can effectively and significantly improve the performances of the IQA metrics with Mean Structural SIMilarity (MSSIM) or Phase Quantization Code (PQC). It is confirmed that the proposed VPPS demonstrates promising results for improving the performances of existing IQA metrics.展开更多
·AIM:To compare visual quality after unilateral cataract surgery with implantation of trifocal intraocular lens(IOL)and asymmetric refractive multifocal IOL.·METHODS:The prospective nonrandom,comparative stu...·AIM:To compare visual quality after unilateral cataract surgery with implantation of trifocal intraocular lens(IOL)and asymmetric refractive multifocal IOL.·METHODS:The prospective nonrandom,comparative study consisted of 60 eyes of 60 patients suffering unilateral cataract surgery with implantation of two different IOLs:AT LISA tri 839 MP(30 eyes;Carl Zeiss Meditec,Germany)and LS-313 MF30(30 eyes;Oculentis GmbH,Germany).Visual acuity,refractive outcome,contrast sensitivity,defocus curves,quality of vision,and optical phenomena were evaluated at3 mo postoperatively.·RESULTS:There were no statistical differences between groups in uncorrected distance visual acuity(P=0.13)and uncorrected near visual acuity(P=0.54).In contrast,uncorrected intermediate visual acuity was better in trifocal group compared to the refractive multifocal group(P=0.02).No significant statistical between-group difference was detected in cylinder(P=0.43).Compared to trifocal group,spherical refraction and spherical equivalent in refractive multi focal group were more myopic(P<0.01).Under photopic conditions,no significant statistical differences were found between groups in contrast sensitivity at 3 and 6 cycles per degree(cpd).The refractive multifocal group performed better at 12 and 18 cpd than the trifocal group(P=0.01,P=0.034,respectively).The questionnaires of quality of vision and optical phenomena showed no differences between groups.·CONCLUSION:Trifocal IOL is superior to refractive multifocal IOL in intermediate visual acuity.Rotationally asymmetric refractive multifocal IOL is more myopic in automated refraction and significantly better for the photopic contrast sensitivity at high frequency.展开更多
AIMTo analyze the relationship between two visual functions and refractive, topographic, pachymetric and aberrometric indicators in eyes with keratoconus.METHODSCorrected distance visual acuity (CDVA), and letter cont...AIMTo analyze the relationship between two visual functions and refractive, topographic, pachymetric and aberrometric indicators in eyes with keratoconus.METHODSCorrected distance visual acuity (CDVA), and letter contrast sensitivity (CS) were correlated with refraction, corneal topography, pachymetry, and total corneal wavefront data prospectively in 71 eyes with keratoconus. The topographic indices assessed were simulated keratometry for the flattest and steepest meridians (SimK1 and SimK2), posterior steeper K (Ks), elevation value in best-fit sphere (BFS) maps, squared eccentricity (Є<sup>2</sup>), aspheric asymmetric index (AAI), pachymetry, thickness progression index (TPI), the amount of pachymetric decentralization (APD), and GalileiTM-keratoconus indices.RESULTSThe mean CDVA (expressed as logMAR) were 0.25±0.21. The mean CS was 1.25±0.46. The spherical refraction correlated well with CDVA (r=-0.526, P<0.001). From topographic indices, SRI correlated with CS (r=-0.695), and IAI with CS (r=-0.672) (P<0.001 for all). Root mean square (RMS) was 4.3±1.81 µm, spherical aberration (SA) was -0.4±0.67 µm, vertical and horizontal coma were -2.1±1.47 and -0.4±0.72 µm. All wavefront data (except horizontal coma), AAI, Є<sup>2</sup> and maximum BFS correlated significantly with the visual function (P≤0.001 for all).CONCLUSIONIn this study, CS is more affected than CDVA as a visual function. The quantity and quality of vision is significantly correlated with well-known and new topographic indices. There is not a significant correlation between visual function and pachymetric parameters. The significantly correlated indices can be used in staging keratoconus and to follow the outcome of a treatment.展开更多
目的:观察并比较AT LISA tri 839MP三焦点人工晶体及CT SPHERIS 209M单焦点人工晶体植入术后高度近视患者的视力、对比敏感度和视觉质量。方法:行白内障超声乳化摘除联合人工晶体植入术的患者44例(44眼),其中三焦组22例(22眼),术中植入A...目的:观察并比较AT LISA tri 839MP三焦点人工晶体及CT SPHERIS 209M单焦点人工晶体植入术后高度近视患者的视力、对比敏感度和视觉质量。方法:行白内障超声乳化摘除联合人工晶体植入术的患者44例(44眼),其中三焦组22例(22眼),术中植入AT LISA tri 839MP三焦点人工晶体,单焦组22例(22眼),术中植入CT SPHERIS 209M单焦点人工晶体。术后3个月检查患者的裸眼远距离视力(uncorrected distance visual acuity,UCDVA)、裸眼中距离视力(uncorrected intermediate vi-sual acuity,UCIVA)、裸眼近距离视力(uncorrected near visualacuity,UCNVA)、最佳矫正远视力(best corrected distance visual acuity,BCDVA)、远视力矫正下的中距离视力(distance corrected intermediate visual acuity,DCIVA)、远视力矫正下的近距离视力(distance corrected near visual acuity,DCNVA),明、暗环境中不同空间频率(3、6、12、18 cpd)下的对比敏感度,并进行脱镜率、不良视觉症状和满意度等问卷调查。采用SPSS16.0统计软件对结果进行统计分析。结果:术后3个月三焦组UCIVA、UCN-VA、DCIVA和DCNVA、脱镜率及满意度优于单焦组(P均<0.05)。在明、暗环境中的18 cpd空间频率,单焦组的对比敏感度优于三焦组(P均<0.05)。两组均有轻度眩光和光晕不适主诉,组间差异无统计学意义(P=0.50)。结论:与CT SPHERIS 209M单焦点人工晶状体比较,AT LISA tri 839MP三焦点人工晶体为高度近视患者提供了更好的中、近视力,脱镜率和满意度均高于单焦点人工晶体。展开更多
图像质量的客观评价方法研究在实现图像质量评价仪器化的过程中起到决定性的作用。在分析最新全参考图像质量评价算法:特征相似法(feature similarity,FSIM)的基础上,利用对比敏感度函数(contrast sensitivity function,CSF)算子以及离...图像质量的客观评价方法研究在实现图像质量评价仪器化的过程中起到决定性的作用。在分析最新全参考图像质量评价算法:特征相似法(feature similarity,FSIM)的基础上,利用对比敏感度函数(contrast sensitivity function,CSF)算子以及离散余弦变换(discrete cosine transform,DCT)域的对比度掩盖效应,提出了一种改进的FSIM图像质量评价方法。该方法具有FSIM算法简单、高效等特性,同时又充分体现人眼视觉特性,更好地反映了人的主观感受。LIVE(laboratory for image and video engi-neering)测试数据集的实验结果证明,该方法在非线性回归后相关系数、斯皮尔曼相关系数、线外率等指标方面均优于传统的其他图像质量评价算法。展开更多
目的比较植入AcryS of ReS TOR及Tecnis ZMB00多焦点人工晶状体(multifocal intraocular lens,MIOL)术后患者的视觉质量。方法回顾性病例对照分析2012年1月至2013年6月期间在我院眼科行白内障超声乳化联合MIOL植入术的患者32例(43眼),...目的比较植入AcryS of ReS TOR及Tecnis ZMB00多焦点人工晶状体(multifocal intraocular lens,MIOL)术后患者的视觉质量。方法回顾性病例对照分析2012年1月至2013年6月期间在我院眼科行白内障超声乳化联合MIOL植入术的患者32例(43眼),根据植入的MIOL不同分为两组,分别为植入AcryS of ReS TOR+4 D MIOL的A组,17例(22眼);植入Tecnis ZMB00+4 D MIOL的T组,15例(21眼)。术后随访3个月,使用标准对数视力表测量裸眼远视力(5 m)及Colenbrander MixedContrast视力测试卡测量中距离视力(66 cm)及近视力(40 cm)。术后3个月时测量明视、暗视和眩光状态时不同空间频率下的对比敏感度,同时对患者视觉干扰、满意度及脱镜率进行问卷调查。结果术后3个月,两组间裸眼远视力、中距离视力及近视力差异均无统计学意义(均为P>0.05)。两组在明视及明视眩光状态时3 c·d-1、6 c·d-1、12 c·d-1、18 c·d-1空间频率下的对比敏感度差异均无统计学意义(均为P>0.05);暗视及暗视眩光状态下时,T组在6 c·d-1、12 c·d-1、18 c·d-1空间频率下对比敏感度要优于A组,差异均有统计学意义(均为P<0.05),在低空间频率(3 c·d-1)下两组间差异均无统计学意义(均为P>0.05)。问卷调查示两组患者术后均极少出现影响正常生活的视觉干扰现象,术后满意度差异不明显。结论 AcryS of ReS TOR+4 D阶梯渐进衍射型MIOL及Tecnis ZMB00+4 D全光学面衍射型MIOL均能为白内障患者提供满意的全程视力,尽管在暗视及暗视状态下眩光时的高空间频率下Tecnis ZMB00 MIOL对比敏感度要优于AcryS of ReS TOR MIOL,但对于绝大多数患者日常生活质量无明显影响。展开更多
文摘AIM：To assess the effects of upper lid blepharoplasty on visual quality.METHODS：Seventy-three eyelids of 39 patients were subjected to upper lid blepharoplasty.Pre- and postoperative contrast sensitivity,visual acuity,vertical palpebral aperture and the degree of lash ptosis were measured.RESULTS：The mean log contrast sensitivities under photopic（P =0.017） and scotopic conditions（P =0.009）were improved after surgery,and these differences were significant.The degree of lash ptosis was also decreased after blepharoplasty（P〈0.001）.CONCLUSION：In our study,a significant increase in contrast sensitivity was found after surgery.These results suggest that upper lid blepharoplasty can be helpful for improving visual quality.
基金Supported by the National Natural Science Foundation of China (No. 60832003, 60902096, 61171163, 61071120)the Scientific Research Foundation of Graduate School of Ningbo University
文摘Most of Image Quality Assessment (IQA) metrics consist of two processes. In the first process, quality map of image is measured locally. In the second process, the last quality score is converted from the quality map by using the pooling strategy. The first process had been made effective and significant progresses, while the second process was always done in simple ways. In the second process of the pooling strategy, the optimal perceptual pooling weights should be determined and computed according to Human Visual System (HVS). Thus, a reliable spatial pooling mathematical model based on HVS is an important issue worthy of study. In this paper, a new Visual Perceptual Pooling Strategy (VPPS) for IQA is presented based on contrast sensitivity and luminance sensitivity of HVS. Experimental results with the LIVE database show that the visual perceptual weights, obtained by the proposed pooling strategy, can effectively and significantly improve the performances of the IQA metrics with Mean Structural SIMilarity (MSSIM) or Phase Quantization Code (PQC). It is confirmed that the proposed VPPS demonstrates promising results for improving the performances of existing IQA metrics.
基金Supported by Key Research and Development Projects of Shaanxi Province(No.2017SF-246)Science and Technology Planning Project of Xi’an(No.2017116SF/YX010No.201805097YX5SF31)。
文摘·AIM:To compare visual quality after unilateral cataract surgery with implantation of trifocal intraocular lens(IOL)and asymmetric refractive multifocal IOL.·METHODS:The prospective nonrandom,comparative study consisted of 60 eyes of 60 patients suffering unilateral cataract surgery with implantation of two different IOLs:AT LISA tri 839 MP(30 eyes;Carl Zeiss Meditec,Germany)and LS-313 MF30(30 eyes;Oculentis GmbH,Germany).Visual acuity,refractive outcome,contrast sensitivity,defocus curves,quality of vision,and optical phenomena were evaluated at3 mo postoperatively.·RESULTS:There were no statistical differences between groups in uncorrected distance visual acuity(P=0.13)and uncorrected near visual acuity(P=0.54).In contrast,uncorrected intermediate visual acuity was better in trifocal group compared to the refractive multifocal group(P=0.02).No significant statistical between-group difference was detected in cylinder(P=0.43).Compared to trifocal group,spherical refraction and spherical equivalent in refractive multi focal group were more myopic(P<0.01).Under photopic conditions,no significant statistical differences were found between groups in contrast sensitivity at 3 and 6 cycles per degree(cpd).The refractive multifocal group performed better at 12 and 18 cpd than the trifocal group(P=0.01,P=0.034,respectively).The questionnaires of quality of vision and optical phenomena showed no differences between groups.·CONCLUSION:Trifocal IOL is superior to refractive multifocal IOL in intermediate visual acuity.Rotationally asymmetric refractive multifocal IOL is more myopic in automated refraction and significantly better for the photopic contrast sensitivity at high frequency.
文摘AIMTo analyze the relationship between two visual functions and refractive, topographic, pachymetric and aberrometric indicators in eyes with keratoconus.METHODSCorrected distance visual acuity (CDVA), and letter contrast sensitivity (CS) were correlated with refraction, corneal topography, pachymetry, and total corneal wavefront data prospectively in 71 eyes with keratoconus. The topographic indices assessed were simulated keratometry for the flattest and steepest meridians (SimK1 and SimK2), posterior steeper K (Ks), elevation value in best-fit sphere (BFS) maps, squared eccentricity (Є<sup>2</sup>), aspheric asymmetric index (AAI), pachymetry, thickness progression index (TPI), the amount of pachymetric decentralization (APD), and GalileiTM-keratoconus indices.RESULTSThe mean CDVA (expressed as logMAR) were 0.25±0.21. The mean CS was 1.25±0.46. The spherical refraction correlated well with CDVA (r=-0.526, P<0.001). From topographic indices, SRI correlated with CS (r=-0.695), and IAI with CS (r=-0.672) (P<0.001 for all). Root mean square (RMS) was 4.3±1.81 µm, spherical aberration (SA) was -0.4±0.67 µm, vertical and horizontal coma were -2.1±1.47 and -0.4±0.72 µm. All wavefront data (except horizontal coma), AAI, Є<sup>2</sup> and maximum BFS correlated significantly with the visual function (P≤0.001 for all).CONCLUSIONIn this study, CS is more affected than CDVA as a visual function. The quantity and quality of vision is significantly correlated with well-known and new topographic indices. There is not a significant correlation between visual function and pachymetric parameters. The significantly correlated indices can be used in staging keratoconus and to follow the outcome of a treatment.
文摘目的:观察并比较AT LISA tri 839MP三焦点人工晶体及CT SPHERIS 209M单焦点人工晶体植入术后高度近视患者的视力、对比敏感度和视觉质量。方法:行白内障超声乳化摘除联合人工晶体植入术的患者44例(44眼),其中三焦组22例(22眼),术中植入AT LISA tri 839MP三焦点人工晶体,单焦组22例(22眼),术中植入CT SPHERIS 209M单焦点人工晶体。术后3个月检查患者的裸眼远距离视力(uncorrected distance visual acuity,UCDVA)、裸眼中距离视力(uncorrected intermediate vi-sual acuity,UCIVA)、裸眼近距离视力(uncorrected near visualacuity,UCNVA)、最佳矫正远视力(best corrected distance visual acuity,BCDVA)、远视力矫正下的中距离视力(distance corrected intermediate visual acuity,DCIVA)、远视力矫正下的近距离视力(distance corrected near visual acuity,DCNVA),明、暗环境中不同空间频率(3、6、12、18 cpd)下的对比敏感度,并进行脱镜率、不良视觉症状和满意度等问卷调查。采用SPSS16.0统计软件对结果进行统计分析。结果:术后3个月三焦组UCIVA、UCN-VA、DCIVA和DCNVA、脱镜率及满意度优于单焦组(P均<0.05)。在明、暗环境中的18 cpd空间频率,单焦组的对比敏感度优于三焦组(P均<0.05)。两组均有轻度眩光和光晕不适主诉,组间差异无统计学意义(P=0.50)。结论:与CT SPHERIS 209M单焦点人工晶状体比较,AT LISA tri 839MP三焦点人工晶体为高度近视患者提供了更好的中、近视力,脱镜率和满意度均高于单焦点人工晶体。
文摘图像质量的客观评价方法研究在实现图像质量评价仪器化的过程中起到决定性的作用。在分析最新全参考图像质量评价算法:特征相似法(feature similarity,FSIM)的基础上,利用对比敏感度函数(contrast sensitivity function,CSF)算子以及离散余弦变换(discrete cosine transform,DCT)域的对比度掩盖效应,提出了一种改进的FSIM图像质量评价方法。该方法具有FSIM算法简单、高效等特性,同时又充分体现人眼视觉特性,更好地反映了人的主观感受。LIVE(laboratory for image and video engi-neering)测试数据集的实验结果证明,该方法在非线性回归后相关系数、斯皮尔曼相关系数、线外率等指标方面均优于传统的其他图像质量评价算法。
文摘目的比较植入AcryS of ReS TOR及Tecnis ZMB00多焦点人工晶状体(multifocal intraocular lens,MIOL)术后患者的视觉质量。方法回顾性病例对照分析2012年1月至2013年6月期间在我院眼科行白内障超声乳化联合MIOL植入术的患者32例(43眼),根据植入的MIOL不同分为两组,分别为植入AcryS of ReS TOR+4 D MIOL的A组,17例(22眼);植入Tecnis ZMB00+4 D MIOL的T组,15例(21眼)。术后随访3个月,使用标准对数视力表测量裸眼远视力(5 m)及Colenbrander MixedContrast视力测试卡测量中距离视力(66 cm)及近视力(40 cm)。术后3个月时测量明视、暗视和眩光状态时不同空间频率下的对比敏感度,同时对患者视觉干扰、满意度及脱镜率进行问卷调查。结果术后3个月,两组间裸眼远视力、中距离视力及近视力差异均无统计学意义(均为P>0.05)。两组在明视及明视眩光状态时3 c·d-1、6 c·d-1、12 c·d-1、18 c·d-1空间频率下的对比敏感度差异均无统计学意义(均为P>0.05);暗视及暗视眩光状态下时,T组在6 c·d-1、12 c·d-1、18 c·d-1空间频率下对比敏感度要优于A组,差异均有统计学意义(均为P<0.05),在低空间频率(3 c·d-1)下两组间差异均无统计学意义(均为P>0.05)。问卷调查示两组患者术后均极少出现影响正常生活的视觉干扰现象,术后满意度差异不明显。结论 AcryS of ReS TOR+4 D阶梯渐进衍射型MIOL及Tecnis ZMB00+4 D全光学面衍射型MIOL均能为白内障患者提供满意的全程视力,尽管在暗视及暗视状态下眩光时的高空间频率下Tecnis ZMB00 MIOL对比敏感度要优于AcryS of ReS TOR MIOL,但对于绝大多数患者日常生活质量无明显影响。
