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Effect of astigmatism and spherical equivalent correction on contrast sensitivity
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作者 Maryam Saffarizadeh Saeed Rahmani +1 位作者 Alireza Akbarzadeh Baghban Mohammad Ghassemi-Broumand 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第12期2243-2247,共5页
AIM:To investigate the effect of astigmatism and spherical equivalent(SE)correction on contrast sensitivity(CS).METHODS:In this cross-sectional study,103 visually normal subjects aged 18 to 36y with bilateral regular ... AIM:To investigate the effect of astigmatism and spherical equivalent(SE)correction on contrast sensitivity(CS).METHODS:In this cross-sectional study,103 visually normal subjects aged 18 to 36y with bilateral regular astigmatism in range of 1.00 diopter cylinder(DC)to 4.00 DC and normal best-corrected visual acuity(20/20)were recruited.Binocular CS was assessed by linear sine-wave gratings at 1.5,3,6,12,and 18 cycles per degree(cpd),before correction of astigmatism,after full correction of astigmatism by cylindrical spectacle lenses,and after SE of refractive error.The repeated measures ANOVA and Bonferroni test were used to compare the effects of astigmatism correction on logCS.RESULTS:Totally 39 patients were male and 64 patients were female with the mean age of 28.25±5.38y.The average degree of astigmatism in right and left eye was 2.03±0.83 and 2.10±0.78,respectively.Increases in uncorrected astigmatic power correlated with decreases in the logCS,especially at high spatial frequencies.A statistically significant difference in logCS was found between these three cases:before correction of astigmatism,after SE of refractive error,and after full correction of astigmatism by cylindrical spectacle lenses at all frequencies(P<0.001),except at 18 cpd.At 18 cpd,there was no statistically significant difference between logCS before and after SE of refractive error(P=1.0).Also,there was no statistically significant difference in mean CS between with-the-rule(WTR)and against-the-rule(ATR)astigmatism,before correction of astigmatism,after correction of astigmatism with cylindrical lenses,and after SE of refractive error.CONCLUSION:Binocular astigmatism defocus decreases CS depending on the degree of astigmatism power;correction of this will improve patent’s quality of vision.Although high astigmatism refractive error(more than 2.00 DC)that is fully corrected by cylindrical spectacle lenses doesn’t increase the CS to the maximum value,especially at higher spatial frequencies(12 and 18).Also SE refractive error effects on improving CS in low astigmatism power(less than 2.00 DC),especially at lower spatial frequencies. 展开更多
关键词 ASTIGMATISM contrast sensitivity spherical equivalent
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Psychophysics in the ophthalmological practice—Ⅱ.Contrast sensitivity
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作者 Claudio Rosa Carlo Aleci 《Annals of Eye Science》 2022年第4期27-39,共13页
Contrast is the differential luminance between one object and another.Contrast sensitivity(CS)quantifies the ability to detect this difference:estimating contrast threshold provides information about the quality of vi... Contrast is the differential luminance between one object and another.Contrast sensitivity(CS)quantifies the ability to detect this difference:estimating contrast threshold provides information about the quality of vision and helps diagnose and monitor eye diseases.High contrast visual acuity assessment is traditionally performed in the eye care practice,whereas the estimate of the discrimination of low contrast targets,an important complementary task for the perception of details,is far less employed.An example is driving when the contrast between vehicles,obstacles,pedestrians,and the background is reduced by fog.Many conditions can selectively degrade CS,while visual acuity remains intact.In addition to spatial CS,“temporal”CS is defined as the ability to discriminate luminance differences in the temporal domain,i.e.,to discriminate information that reaches the visual cortex as a function of time.Likewise,temporal sensitivity of the visual system can be investigated in terms of critical fusion frequency(CFF),an indicator of the integrity of the magnocellular system that is responsible for the perception of transient stimulations.As a matter of fact,temporal resolution can be abnormal in neuro-ophthalmological clinical conditions.This paper aims at considering CS and its application to the clinical practice. 展开更多
关键词 contrast sensitivity(cs) MAGNOCELLULAR sine-wave grating temporal processing FLICKER
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Contrast Detection Learning Improves Visual Contrast Sensitivity of Cat 被引量:6
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作者 华田苗 王振华 +1 位作者 徐金旺 刁建刚 《Zoological Research》 CAS CSCD 北大核心 2010年第2期155-162,共8页
Psychological studies on human subjects show that contrast detection learning promote learner's sensitivity to visual stimulus contrast. The underlying neural mechanisms remain unknown. In this study, three cats (Fe... Psychological studies on human subjects show that contrast detection learning promote learner's sensitivity to visual stimulus contrast. The underlying neural mechanisms remain unknown. In this study, three cats (Felis catus) were trained to perform monocularly a contrast detection task by two-altemative forced choice method. The perceptual ability of each cat improved remarkably with learning as indicated by a significantly increased contrast sensitivity to visual stimuli. The learning effect displayed an evident specificity to the eye employed for learning but could partially transfer to the naive eye, prompting the possibility that contrast detection learning might cause neural plasticity before and after the information from both eyes are merged in the visual pathway. Further, the contrast sensitivity improvement was evident basically around the spatial frequency (SF) used for learning, which suggested that contrast detection learning effect showed, to some extent, a SF specificity. This study indicates that cat exhibits a property of contrast detection learning similar to human subjects and can be used as an animal model for subsequent investigations on the neural correlates that mediate learning-induced contrast sensitivity improvement in humans. 展开更多
关键词 VISUAL contrast detection LEARNING contrast sensitivity CAT
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Decreased contrast sensitivity of visual cortical cells to visual stimuli accompanies a reduction of intracortical inhibition in old cats 被引量:2
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作者 周俊 施夏明 +2 位作者 彭青松 化国鹏 华田苗 《Zoological Research》 CAS CSCD 北大核心 2011年第5期533-539,共7页
Psychophysical experiments on human and animal subjects have proven that aged individuals show significantly reduced visual contrast sensitivity compared with young adults.To uncover the possible neural mechanisms,we ... Psychophysical experiments on human and animal subjects have proven that aged individuals show significantly reduced visual contrast sensitivity compared with young adults.To uncover the possible neural mechanisms,we used extracellular single-unit recording techniques to examine the response of V1(primary visual cortex) neurons as a function of visual stimulus contrast in both old and young adult cats(Felis catus).The mean contrast sensitivity of V1 neurons to visual stimuli in old cats decreased significantly relative to young adult cats,consistent with findings reported in old primates.These results indicate that aging can affect contrast sensitivity of visual cortical cells in both primate and non-primate mammalian animals,and might contribute to the reduction of perceptual visual contrast sensitivity in aged individuals.Further,V1 cells of old cats exhibited increased responsiveness,decreased signal-to-noise ratio,and enlarged receptive field(RF) size compared with that of young adult cats,which indicated that decreased contrast sensitivity of V1 neurons accompanied a reduction of intracortical inhibition during senescence. 展开更多
关键词 contrast sensitivity V1 neurons Old cats Young adult cats
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Effects of higher-order aberrations on contrast sensitivity in normal eyes of a large myopic population 被引量:11
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作者 Peng-Fei Zhao Shi-Ming Li +4 位作者 Jing Lu Hong-Min Song Jing Zhang Yue-Hua Zhou Ning-Li Wang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第9期1407-1411,共5页
AIM:To study the relation between higher-order aberrations(HOAs)and contrast sensitivity(CS)in normal eyes among a population of laser in situ keratomileusis(LASIK)candidates.METHODS:In 6629 eyes of 3315 LASIK... AIM:To study the relation between higher-order aberrations(HOAs)and contrast sensitivity(CS)in normal eyes among a population of laser in situ keratomileusis(LASIK)candidates.METHODS:In 6629 eyes of 3315 LASIK candidates,CS were measured under dark environment at the spatial frequencies of 1.5,3,6,12 and 18 cycles per degree(c/d),respectively,using an Optec 6500 visual function tester.Meanwhile,ocular HOAs were measured for a 6.0 mm pupil with a Hartmann-Shack wavefront analyzer.RESULTS:In the study,the subjects with an average spherical equivalent of-4.86±2.07 D were included.HOAs decreased from the third to the sixth order aberrations with predominant aberrations of third-order coma,trefoil and fourth-order spherical aberration.At low and moderate spatial frequencies,CS was negatively correlated with the third-order coma and trefoil aberrations,and decreased with increasing Z31,but increased with increasing Z3-3and Z5-1.At high spatial frequencies,CS decreased with increasing Z3-3and increased with increasing Z5-1.CONCLUSION:At a large pupil size of 6.0 mm,the thirdorder aberrations,but not the total aberrations,are the main factors affecting CS.Vertical coma is negatively correlated with CS. 展开更多
关键词 MYOPIA contrast sensitivity higher-orderaberrations COMA spherical aberration
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Contrast sensitivity in 14 MeV fast neutron radiography 被引量:5
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作者 Chang-Bing Lu Jie Bao +4 位作者 Ying Huang Peng Xu Xiong-Jun Chen Qi-Wei Zhang Xi-Chao Ruan 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第6期115-122,共8页
Fast neutron radiography(FNR) is an effective non-destructive testing technique.Due to the scattering effect and low detection efficiency,the detection limit of FNR under certain conditions cannot be determined.In ord... Fast neutron radiography(FNR) is an effective non-destructive testing technique.Due to the scattering effect and low detection efficiency,the detection limit of FNR under certain conditions cannot be determined.In order to obtain the minimum detectable thickness by FNR,we studied the contrast sensitivity of FNR lead samples,both theoretically and experimentally.We then clarified the relationship between pixel value and irradiation time,and sample materials and thickness.Our experiment,using a4-cm-thick lead sample,verified our theoretical expression of FNR contrast sensitivity. 展开更多
关键词 FAST NEUTRON RADIOGRAPHY contrast sensitivity EXPERIMENTAL research
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Relationship between contrast sensitivity and corneal shape following overnight orthokeratology 被引量:5
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作者 Li-Li Liu Li-Ping Gong +3 位作者 Yue-Yuan Xu Xuan Zhu Kaddie Kwok Chen Wei-Feng Liu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第2期275-279,共5页
AIM: To evaluate the relationship between contrast sensitivity(CS) and corneal shape following overnight orthokeratology(OK). METHODS: We conducted a retrospective clinical study of 80 lens-wearing myopia patients, al... AIM: To evaluate the relationship between contrast sensitivity(CS) and corneal shape following overnight orthokeratology(OK). METHODS: We conducted a retrospective clinical study of 80 lens-wearing myopia patients, all of whom had undergone OK and had been evaluated by Orbscan II topography. We measured the surface irregularity index(SIRI) of corneal topography at 3 and 5 mm, the size of the flattened central corneal curvature of OK lens(zone A), the size of the cornea altered by OK lens(zone B), the size of the pupillary area at the corneal level(zone C), the area of crossover between zones A and C(zone AC), the area of crossover between zones B and C(BC), the ratio of BC to B(BC/B), and the ratio of AC to C(AC/C). CS was evaluated using the CSV-1000 with spatial frequencies of 3, 6, 12, and 18 cycles/degree(CPD). RESULTS: Multiple correlation analyses indicated significant negative correlations between CS, zone C, BC/B, and 3-mm SIRI(all P<0.01). There were no significant differences between CS, zone B, AC/A, or 5-mm SIRI(P=0.60, 0.94 and 0.11, respectively). Zone C was negatively correlated with 3, 6, 12, and 18 CPD. 5-mm SIRI were negatively correlated with 6, 12, and 18 CPD. BC/C was negatively correlated with 6 and 18 CPD. AC/C was positively correlated with 3 CPD. CONCLUSION: Zone C, 3-mm SIRI and BC/B affect the CS following overnight OK. 展开更多
关键词 ORTHOKERATOLOGY contrast sensitivity PUPIL size area shaped CORNEA MYOPIA
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Comparison of contrast sensitivity and visual acuity between deep anterior lamellar keratoplasty and penetrating keratoplasty in patients with keratoconus 被引量:3
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作者 Mehmet Orcun Akdemir Baran Kandemir +2 位作者 Isil Bahar Sayman Cem Selvi OmerKamil Dogan 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2012年第6期737-741,共5页
AIM: To evaluate postoperative visual acuity and contrast sensitivity results following deep anterior lamellar keratoplasty (DALK) and penetrating keratoplasty (PK) in patients with keratoconus (KC). METHODS: All the ... AIM: To evaluate postoperative visual acuity and contrast sensitivity results following deep anterior lamellar keratoplasty (DALK) and penetrating keratoplasty (PK) in patients with keratoconus (KC). METHODS: All the patients’ records with KC who had PK or DALK surgery between May 2010 and May 2011 were retrospectively reviewed. Sixty patients who underwent successful corneal transplantation for KC: 30 eyes underwent DALK and 30 eyes underwent PK were included in this study. Preoperative and postoperative mean logarithm of the minimum angle of resolution (logMAR) uncorrected visual acuity (UCVA), logMAR best spectacle-corrected visual acuity (BSCVA) and intraocular pressure (IOP) were evaluated. Contrast sensitivity tests (CS) were done preoperative and 2 months after all sutures had removed. All surgeries were performed under regional anesthesia (retrobulbar anesthesia) by 1 surgeon (B.K.) who was experienced in penetrating and lamellar keratoplasty techniques. RESULTS: The mean age of the DALK group was 29.67±4.95 (range 18-40) years and the PK group was 28.7±3.53 (range 18-39) years. Preoperatively there was no significant difference in the logMAR UCVA, logMAR BSCVA and IOP between the DALK (1.281±0.56; 0.97±0.85; 12.07±2.12mmHg) and PK (1.34±0.21; 0.98±0.21; 13±2.12mmHg) groups. One-year after surgery there was no significant difference in the mean logMAR UCVA and IOP between the DALK (0.46±0.37; 11.73±2.1mmHg) and PK (0.38±0.21; 12±2.12mmHg) groups. The mean contrast sensitivity was evaluated by CC-100 Topcon LCD at 1.5, 2.52, 4.23, 7.10 and 11.91 cycles per degree (cs/deg) spatial frequencies before and 2 months after the all sutures had removed. CONCLUSION: All patients with keratoconus in both DALK and PK groups performed good visual function postoperatively. The mean contrast sensitivity increased considerably at all spatial frequencies compared with preoperative levels in the DALK and PK groups. The mean post-operative evaluation of contrast sensitivity measurements was not significantly different between the two groups. 展开更多
关键词 contrast sensitivity KERATOCONUS corneal transplantation
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Assessment of contrast sensitivity loss after intrastromal femtosecond laser and LASIK procedure 被引量:2
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作者 Elsa L.C.Mai Ie-Bin Lian David C.K.Chang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第12期1798-1801,共4页
AIM: To assess the loss of contrast sensitivity (CS) function for INTRACOR or intrastromal femtosecond laser presbyopia procedure to conventional LASIK procedures.METHODS: Patients were recruited from a refractive... AIM: To assess the loss of contrast sensitivity (CS) function for INTRACOR or intrastromal femtosecond laser presbyopia procedure to conventional LASIK procedures.METHODS: Patients were recruited from a refractive surgery center for either INTRACOR or conventional LASIK. INTRACOR was performed on 8 eyes and LASIK was performed for 40 eyes in an overlapping period. Pre-operative evaluation and post-operative follow up for up to three months was done. Drops of CS in 4 spatial frequency (3 cpd, 6 cpd, 12 cpd and 18 cpd) right before and 3mo after the surgery were compared by Wilcoxon signed ranks test.RESULTS: For INTRACOR, CS threshold showed significant drop at both glare and non-glare condition, the drop was seen in all 4 spatial frequency. The averaged loss over the 4 spatial frequencies 3mo after surgery was 1.18 for non-glare and 0.71 for glare. For LASIK the CS threshold drop was most significant in 12 cpd for glare.CONCLUSION: INTRACOR procedure produces a gain of near vision for presbyopia patients but also introduces a high lost of contrast sensitivity plus worsen of vision quality. Pre-surgical patient selection and advise should be given with specific regards to night driving and glare conditions. 展开更多
关键词 INTRACOR LASIK contrast sensitivity intrastromal femtosecond laser
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Comparison of contrast sensitivity based on the surgical results for intermittent exotropia
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作者 Hae Rang Kim Soo Jung Lee 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第11期1725-1730,共6页
AIM: To compare contrast sensitivity(CS) based on the surgical results for intermittent exotropia(IXT) and to examine the relationship between CS and photophobia.METHODS: Medical records of the patients who underwent ... AIM: To compare contrast sensitivity(CS) based on the surgical results for intermittent exotropia(IXT) and to examine the relationship between CS and photophobia.METHODS: Medical records of the patients who underwent bilateral lateral rectus muscle recession for IXT between 4 and 12 years old were reviewed retrospectively. They were categorized based on the surgical results;successful correction group(n=36) and overcorrection group(esotropia ≥10 PD at 3 mo postoperatively, n=18). Using CGT-2000 test for CS was performed binocularly, and subjective reports of photophobia was investigated preoperatively and at 3 mo postoperatively. Objective photophobia was defined as a significant decrease in CS in the presence of glare.RESULTS: Preoperatively, there was no difference in CS between the groups. Postoperatively, under mesopic conditions, significant improvement of CS was observed at 6.3°, 4°, and 2.5° in the successful correction group and at 6.3° and 4° in the overcorrection group, regardless of glare. Under photopic conditions, at all visual angles except 0.64°, improvement in CS was noted in both groups while CS worsened significantly at 0.64° in the overcorrection group postoperatively. At all visual angles under photopic conditions postoperatively, regardless of glare, CS in the overcorrected group was significantly worse than that in the successful correction group, and CS was significantly decreased by addition of glare in both groups. All patients except one(96.4%) in the successful correction group and 8 patients(61.5%) in overcorrection group showed improvement of photophobia postoperatively, which correlated with CS under photopic conditions(P=0.001, 0.03).CONCLUSION: After surgery for IXT, CS under photopic conditions improve at all visual angles except 0.64°, while CS is significantly worse in the overcorrection group postoperatively at 0.64°. Subjective photophobia havesignificant correlation with CS under photopic conditions, and may be used as an objective indicator of photophobia. 展开更多
关键词 contrast sensitivity INTERMITTENT EXOTROPIA OVERCORRECTION PHOTOPHOBIA SUCCESS
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Age norms for grating acuity and contrast sensitivity measured by Lea tests in the first three years of life
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作者 Amal A.Elgohary Manal H.Abuelela Adel Alei Eldin 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第7期1150-1153,共4页
AIM: To determine age norms in the first three years of life for grating visual acuity and contrast sensitivity obtained with Lea grating test and Hiding Heidi low contrast face test. METHODS: Lea grating test was u... AIM: To determine age norms in the first three years of life for grating visual acuity and contrast sensitivity obtained with Lea grating test and Hiding Heidi low contrast face test. METHODS: Lea grating test was used to estimate binocular grating acuity and Hiding Heidi low contrast face test was used to estimate contrast sensitivity in 600 healthy infants and children. Age ranged from 3 to 36 mo subdivided into 12 groups subjected for full ophthalmologic and pediatric examinations.RESULTS: The grating acuity developed along the first three years of life. It ranged from 1.88±0.32 c/d at 3mo to 30.95±0.77 c/d at 36 mo. The most rapid development was during the first 12 mo and the slowest development was from 30 to 36 mo. The contrast sensitivity showed rapid development in the first two years of life. Its mean value ranged from 4.23±1.17 at 3mo to 78.26±8.21 at 24 mo. It was constant at the highest score(80) thereafter.CONCLUSION: Age norms for grating acuity along with contrast sensitivity offer a more comprehensive measure of spatial vision and should be incorporated in clinical practice for better visual assessment in preverbal and nonverbal children. 展开更多
关键词 grating acuity contrast sensitivity age norms Lea tests preverbal children
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CONTRAST SENSITIVITY IN AMBLYOPIA
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作者 Shaomei Yang De-zheng Wu Ning Tian Lezheng Wu Zhongshan Ophthalmic Centre Sun Yat-sen University of Medical Sciences Guangzhou, China 《眼科学报》 1991年第1期25-28,共4页
Contrast sensitivity function(CSF) for sinusoid gratings of varying spatial frequencies was determined for each eye of 21 cases with unilateral amblyopia. The CSF of all amblyopic eyes, except one, showed reduced sens... Contrast sensitivity function(CSF) for sinusoid gratings of varying spatial frequencies was determined for each eye of 21 cases with unilateral amblyopia. The CSF of all amblyopic eyes, except one, showed reduced sensitivity when compared with the non-amblyopic eye of the same person. The curve showed reduction more significantly at middle and high spatial frequencies. The cut-off frequency was shifted toward lower spatial frequencies. The relationship between CSF and various degree of amblyopia was als... 展开更多
关键词 csF contrast sensitivity IN AMBLYOPIA
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AB037.Preliminary findings from the COMPASS-ND study:reading acuity and contrast sensitivity at different levels of cognitive impairment
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作者 Faisal Al-Yawer Natalie Phillips Walter Wittich 《Annals of Eye Science》 2019年第1期212-212,共1页
Background:Declines in visual function have been reported in individuals with Alzheimer’s disease(AD)and other neurological disorders,and have been associated with cognitive decline seen in those disorders.Here we re... Background:Declines in visual function have been reported in individuals with Alzheimer’s disease(AD)and other neurological disorders,and have been associated with cognitive decline seen in those disorders.Here we report preliminary visual findings from the COMPASS-ND study of the Canadian Consortium on Neurodegeneration in Aging(CCNA)in a diverse group of individuals at various stages of cognitive impairment,diagnosed via clinical consensus and stringent criteria.Methods:Participants were 109 older adults(age range,60-89,M=72.94,SD=7.01)that are part of the CCNA cohort at different stages of cognitive decline(subjective cognitive impairment,SCI,n=24;mild cognitive impairment,MCI,n=64;mild AD,n=21).Reading acuity(MNRead)and contrast sensitivity(Mars test)were tested with habitual correction.We additionally report scores on the Montreal Cognitive Assessment(MoCA)scale for the three groups.Results:Out of all the participants,25%had reduced reading acuity[>0.5 logMAR(20/63)]and 23%presented with moderate to severe loss of contrast sensitivity[<1.48 log CS(3.3%contrast)].Only 6.5%of participants had combined reduced reading acuity and moderate to severe contrast sensitivity.Notably,only 8.3%of individuals with SCI presented with reduced reading acuity,compared to 32.3%and 23.8%of those with MCI and AD,respectively(χ2=5.28,P=0.071).Lower contrast sensitivity was observed in AD participants relative to those with MCI and SCI(P=0.04,ω2=0.04;Figure 1),after adjusting for age,sex and education.No differences in reading acuity were observed(P=0.46,ω2=0.004).Conclusions:Using the Mars test,a measure of the processing of low spatial frequencies,we were able to replicate previous reports of declines in contrast sensitivity in individuals with AD compared to those with MCI and SCI.We also observed higher rates of reduced reading acuity in the AD and MCI groups relative to those reported in the general population.These results set the groundwork for examining the relationship between vision status and cognitive function,brain integrity,quality of life,in these groups. 展开更多
关键词 Cognitive impairment COGNITION visual acuity contrast sensitivity
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Objective electrophysiological contrast sensitivity with monofocal and multifocal intraocular lenses:a prospective clinical study
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作者 Salvatore Cillino Giovanni Cillino +4 位作者 Simona Di Naro Aissa Iggui Viviana Firpo Girolamo Maniscalco Alessandra Casuccio 《Annals of Eye Science》 2018年第1期136-146,共11页
Background:To compare objective electrophysiological contrast sensitivity function(CSF)in patients implanted with either multifocal intraocular lenses(MIOLs)or monofocal intraocular lenses(IOLs)by pattern reversal vis... Background:To compare objective electrophysiological contrast sensitivity function(CSF)in patients implanted with either multifocal intraocular lenses(MIOLs)or monofocal intraocular lenses(IOLs)by pattern reversal visual evoked potentials(prVEP)measurements.Methods:Fourty-five cataract patients were randomly allocated to receive bilaterally:apodized diffractive-refractive Alcon Acrysof MIOL(A),full diffractive AMO Tecnis MIOL(B)or monofocal Alcon Acrysof IOL(C).Primary outcomes:1-year differences in objective binocular CSF measured by prVEP with sinusoid grating stimuli of 6 decreasing contrast levels at 6 spatial frequencies.Secondary outcomes:psychophysical CSF measured with VCTS-6500,photopic uncorrected distance(UDVA),and mesopic and photopic uncorrected near and intermediate visual acuities(UNVA and UIVA respectively).Results:Electrophysiological CSF curve had an inverted U-shaped morphology in all groups,with a biphasic pattern in Group B.Group A showed a lower CSF than group B at 4 and 8 cpd,and a lower value than group C at 8 cpd.Psychophysical CSF in group A exhibited a lower value at 12 cpd than group B.Mean photopic and mesopic UNVA and UIVA were worse in monofocal group compared to the multifocal groups.Mesopic UNVA and UIVA were better in group B.Conclusions:Electrophysiological CSF behaves differently depending on the types of multifocal or monofocal IOLs.This may be related to the visual acuity under certain conditions or to IOL characteristics.This objective method might be a potential new tool to investigate on MIOL differences and on subjective device-related quality of vision. 展开更多
关键词 Electrophysiological contrast sensitivity visual evoked potentials(VEPs) multifocal intraocular lens(MIOLs) prospective clinical study
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SENSITIVITY FACTORS FOR TYPHOON GENESIS OVER THE WESTERN NORTH PACIFIC DURING JULY-SEPTEMBER 被引量:1
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作者 吴胜安 李涛 孔海江 《Journal of Tropical Meteorology》 SCIE 2014年第2期112-120,共9页
The paper compares the correlations between individual factors of the cyclogenesis and the number of TCs formed in the western North Pacific in July to September(NTWNP). It also compares the characteristics of zonal a... The paper compares the correlations between individual factors of the cyclogenesis and the number of TCs formed in the western North Pacific in July to September(NTWNP). It also compares the characteristics of zonal anomaly distribution of the factors in the primary TC source areas of the Northern Hemisphere. Results show that the vorticity factor has the closest correlation with NTWNP. In TC genesis conditions, this feature is relatively rich but not enough, which determines that it is the sensitivity factor of NTWNP's annual variation. The paper also analyzes the source of annual variation of the vorticity factor in the key area of the western North Pacific as well as its advantage in showing NTWNP. Results show that the annual variation of the vorticity factor mentioned above is related to the annual variation of Southern Oscillation, Antarctica Oscillation and the geopotential height field of East Australia, which reflects the effect of two large-scale systems in the Southern Hemisphere and ENSO(El Ni?o–Southern Oscillation) on NTWNP. Since the area where the vorticity factor is significantly correlated with NTWNP is consistent with the area of dense TC genesis sources, the vorticity factor has an obvious advantage in showing annual variation of TCs. Those features are very significant for research on the influencing mechanism of NTWNP and simulation of climate models. 展开更多
关键词 statistical characteristics contrastive analysis vorticity factor sensitivity
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Diagnostic sensitivity of imaging modalities for hepatocellular carcinoma smaller than 2 cm 被引量:7
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作者 Keiji Mita Soo Ryang Kim +7 位作者 Masatoshi Kudo Susumu Imoto Taisuke Nakajima Kenji Ando Katsumi Fukuda Toshiyuki Matsuoka Yoko Maekawa Yoshitake Hayashi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第33期4187-4192,共6页
AIM:To compare the imaging results with histology and to evaluate the diagnostic sensitivity of imaging modalities for hepatocellular carcinoma(HCC)smaller than 2 cm.METHODS:Nodules smaller than 2 cm(n=34)revealed by ... AIM:To compare the imaging results with histology and to evaluate the diagnostic sensitivity of imaging modalities for hepatocellular carcinoma(HCC)smaller than 2 cm.METHODS:Nodules smaller than 2 cm(n=34)revealed by ultrasonography(US)in 29 patients with liver cirrhosis were analyzed.Histological diagnosis of HCC was performed by ultrasonographic guidance:moderately-differentiated HCC(n=24);well-differentiated HCC(n=10).The patterns disclosed by the four imaging modalities defined the conclusive diagnosis of HCC:(1)contrast-enhanced computed tomography(CECT),hypervascularity in the arterial phase and washout in the equilibrium phase;(2)Sonazoid contrast-enhanced US(CEUS),hypervascularity in the early vascular phase and defect in the Kupffer phase;(3)gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid(Gd-EOBDTPA)-enhanced magnetic resonance imaging(MRI),hypervascularity in the arterial phase and/or defect in the hepatobiliary phase;and(4)CT arterioportal angiography:hypervascularity by CT during arteriography and/ or perfusion defect by CT during arterial portography.RESULTS:Overall,the sensitivity of diagnosing HCC smaller than 2 cm was 52.9%(18/34)(95%CI:35.170.2)by CECT;67.6%(23/34)(95%CI:49.5-82.6)by Sonazoid CEUS;76.5%(26/34)(95%CI:58.8-89.3) by Gd-EOB-DTPA MRI;and 88.2%(30/34)(95%CI: 72.5-96.7)by CT arterioportal angiography.The diagnostic sensitivity of detecting moderately-differentiated HCC by CECT,Sonazoid CEUS,Gd-EOB-DTPA MRI and CT arterioportal angiography was 62.5%(15/24)(95%CI: 40.6-81.2),79.2%(19/24)(95%CI:57.8-92.9),75.0% (18/24)(95%CI:53.3-90.2)and 95.8%(23/24)(95% CI:78.9-99.9),respectively.A significant difference(P< 0.05)was observed between CECT and CT arterioportal angiography in all nodules.There was no difference between Sonazoid CEUS,Gd-EOB-DTPA MRI,and CT arterioportal angiography.The combined sensitivity of Sonazoid CEUS and Gd-EOB-DTPA MRI was 94.1%(32/34).CONCLUSION:Changing the main diagnostic modality for HCC smaller than 2 cm from CT arterioportal angiography to Sonazoid CEUS and Gd-EOB-DTPA MRI is recommended. 展开更多
关键词 Computed tomography arterioportal angi- ography contrast-enhanced computed tomography Diagnostic sensitivity Gd-EOB-DTPA-enhanced magnetic resonance imaging Hepatocellular carcinoma smaller than 2 cm:Sonazoid contrast-enhanced ultrasonography
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Correlation of Enhancement Degree on Contrast-enhanced Ultrasound with Histopathology of Carotid Plaques and Serum High Sensitive C-Reactive Protein Levels in Patients Undergoing Carotid Endarterectomy 被引量:3
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作者 熊莉 孙伟军 +3 位作者 蔡华英 杨园 朱江 赵博文 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2017年第3期425-428,共4页
This study was undertaken to investigate the correlation of the enhancement degree on contrast-enhanced ultrasound(CEUS) with the histopathology of carotid plaques and the serum high sensitive C-reactive protein(hs-CR... This study was undertaken to investigate the correlation of the enhancement degree on contrast-enhanced ultrasound(CEUS) with the histopathology of carotid plaques and the serum high sensitive C-reactive protein(hs-CRP) levels in patients undergoing carotid endarterectomy(CEA). Carotid CEUS was performed preoperatively in 115 patients who would undergo CEA, and the enhancement degree of the carotid plaques was evaluated by both the visual semiquantitative analysis and the quantitative time-intensity curve analysis. Serum hs-CRP levels were detected using the particle-enhanced immunoturbidimetric assay also before the operation. Additionally, the carotid plaque samples were subjected to histopathological examination postoperatively. The density of neovessels and the number of macrophages in the plaques were assessed by immunohistochemistry. The results showed that among the 115 patients, grade 0 plaque contrast enhancement was noted in 35 patients, grade 1 in 48 patients and grade 2 in 32 patients. The degree of plaque enhancement, the density of neovessels, the number of macrophages, and the hs-CRP levels were highest in the grade 2 patients. Correlation analysis showed that the enhancement degree of the carotid plaques was closely related to the immunohistochemical parameters of the plaques and the serum hs-CRP levels. It was suggested that the carotid plaque enhancement on CEUS can be used to evaluate the vulnerability of carotid plaques. 展开更多
关键词 carotid plaque NEOVASCULARIZATION contrast-enhanced ultrasound carotid endarterectomy high sensitive C-reactive protein
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白内障超声乳化联合IOL植入术后并发CCS的危险因素分析 被引量:1
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作者 王立肖 张剑锋 张恒 《海南医学》 CAS 2023年第3期368-371,共4页
目的分析白内障超声乳化联合人工晶体(IOL)植入术后并发囊袋收缩综合征(CCS)的危险因素。方法选择2020年1月至2020年12月在宝鸡市人民医院眼科接受白内障超声乳化联合IOL植入术的100例患者展开研究,根据患者术后3个月CCS的发生情况分为... 目的分析白内障超声乳化联合人工晶体(IOL)植入术后并发囊袋收缩综合征(CCS)的危险因素。方法选择2020年1月至2020年12月在宝鸡市人民医院眼科接受白内障超声乳化联合IOL植入术的100例患者展开研究,根据患者术后3个月CCS的发生情况分为CCS组7例,无CCS组93例。比较两组患者术前及术后3个月的最佳矫正视力(BCVA)、对比敏感度(CSF),并对影响白内障超声乳化联合IOL植入术后并发CCS的原因进行单因素分析和多因素Logistic回归分析。结果CCS组患者术前BCVA以及CSF 1.5c/d、6c/d、18c/d分别为(0.48±0.07)LogMAR、1.45±0.13、1.06±0.14、0.05±0.01,明显低于无CCS组的(0.57±0.11)LogMAR、1.59±0.16、1.22±0.16、0.07±0.02,CCS组患者术后3个月时,BCVA以及CSF 1.5c/d、6c/d、18c/d分别为(0.69±0.08)LogMAR、1.68±0.17、1.48±0.16、0.21±0.03,明显低于无CCS组的(0.83±0.07)LogMAR、1.87±0.15、1.76±0.18、0.35±0.05,差异均有统计学意义(P<0.05);经单因素分析结果显示,两组患者的年龄以及有无糖尿病、青光眼、葡萄膜炎、高度近视、视网膜色素变性、IOL植入材料比较差异均有统计学意义(P<0.05);经多因素Logistic回归分析结果显示,年龄、糖尿病、青光眼、葡萄膜炎、高度近视、视网膜色素变性、IOL植入材料均是导致白内障超声乳化联合IOL植入术后并发CCS的危险因素(P<0.05)。结论白内障超声乳化联合IOL植入术后并发CCS的危险因素包括年龄、糖尿病、青光眼、葡萄膜炎、高度近视、视网膜色素变性、IOL植入材料,临床上可根据上述危险因素早期干预,以期减少CCS的发生。 展开更多
关键词 白内障超声乳化术 人工晶体 囊袋收缩综合征 最佳矫正视力 对比敏感度 危险因素
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Impact of Lutein-Based Food Supplement on Macular Pigment, Glare and Contrast Vision
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作者 Peter Sutter 《Open Journal of Ophthalmology》 2023年第3期316-326,共11页
Purpose: To evaluate the impact of a specially formulated food supplement containing 20 mg free lutein and 2.8 mg zeaxanthin on macular pigment volume (MPV) and visual function. Methods: In this prospective non-compar... Purpose: To evaluate the impact of a specially formulated food supplement containing 20 mg free lutein and 2.8 mg zeaxanthin on macular pigment volume (MPV) and visual function. Methods: In this prospective non-comparative study healthy subjects were instructed to take one capsule of Eagle Eye Lutein 20 Vision Caps (Innomedis AG) per day with a meal for 6 months. MPV was measured with the MP-Eye system (AzulOptics) after 3 and 6 months of treatment. Mesopic vision (MV), glare sensitivity (GS) and contrast vision threshold (CVT) were measured with the Binoptometer 4P system (OCULUS Optikgeräte). Results: Twenty-three healthy subjects between 19 and 56 years were enrolled. A significant increase was observed in MPV (p Conclusions: The specially formulated food supplement containing lutein and zeaxanthin induced a significant increase in MPV, and consequently an improvement in the visual function after 3 and 6 months in healthy subjects. 展开更多
关键词 Macular Pigment Mesopic Vision Glare Disability contrast sensitivity LUTEIN ZEAXANTHIN
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Impact of Lutein-Based Food Supplement on Macular Pigment, Glare and Contrast Vision
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作者 Peter Sutter 《Open Journal of Biophysics》 2023年第3期316-326,共11页
Purpose: To evaluate the impact of a specially formulated food supplement containing 20 mg free lutein and 2.8 mg zeaxanthin on macular pigment volume (MPV) and visual function. Methods: In this prospective non-compar... Purpose: To evaluate the impact of a specially formulated food supplement containing 20 mg free lutein and 2.8 mg zeaxanthin on macular pigment volume (MPV) and visual function. Methods: In this prospective non-comparative study healthy subjects were instructed to take one capsule of Eagle Eye Lutein 20 Vision Caps (Innomedis AG) per day with a meal for 6 months. MPV was measured with the MP-Eye system (AzulOptics) after 3 and 6 months of treatment. Mesopic vision (MV), glare sensitivity (GS) and contrast vision threshold (CVT) were measured with the Binoptometer 4P system (OCULUS Optikgeräte). Results: Twenty-three healthy subjects between 19 and 56 years were enrolled. A significant increase was observed in MPV (p Conclusions: The specially formulated food supplement containing lutein and zeaxanthin induced a significant increase in MPV, and consequently an improvement in the visual function after 3 and 6 months in healthy subjects. 展开更多
关键词 Macular Pigment Mesopic Vision Glare Disability contrast sensitivity LUTEIN ZEAXANTHIN
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