The relationship between macular pigment and visual performance

This study was designed to assess whether macular pigment optical density (MPOD) is associated with visual performance. One hundred and forty-two young healthy subjects were recruited. Macular pigment optical density and visual performance were assessed by psychophysical tests including best corrected visual acuity (BCVA), mesopic and photopic contrast sensitivity, glare sensitivity, photostress recovery time (PRT). Measures of central visual function, including BCVA and contrast sensitivity, were positively associated with MPOD (p < 0.05, for all). Photostress recovery and glare sensitivity were unrelated to MPOD (p > 0.05). A longitudinal, placebo-controlled and randomized supplementation trial will be required to ascertain whether augmentation of MPOD can influence visual performance.     

Contralateral comparison of visual outcome of AcrySof IQ and SA60AT intraocular lenses

Objective: To compare the visual performance of aspherical AcrySof IQ (SN60WF) and SA60AT spherical intraocular lenses after cataract surgery. Design: Prospective comparative study.Participants: Seventy eyes of 35 patients who underwent phacoemulsification for cataract surgery.Methods: The IQ lens was implanted in one eye and the SA60AT lens in the other eye of every patient. Refraction, uncorrected visual acuity (UCVA), and best spectacle-corrected visual acuity (BSCVA) were measured 1 and 3 months after surgery. At 3 months’ follow-up, the quality of vision, in terms of contrast sensitivity (CS) with and without glare and higher-order aberrations (HOA), was also determined.Results: At 3 months postoperative, the mean UCVA in the IQ and SA60AT groups was 0.25 (SD 0.26) and 0.30 (SD 0.27), respectively, and BSCVA was 0.10 (SD 0.16) in both groups. Spherical refractive error was -0.56 (SD 1.03) D and -0.47 (SD 0.64) D in the IQ and SA groups, respectively. In photopic conditions without glare, IQ eyes had statistically significant better CS at 12 cycles per degree (cpd) and better function at 3 and 18 cpd, and in mesopic conditions without glare, IQ eyes also had better results at 3, 12, and 18 cpd. In mesopic conditions with glare, IQ eyes also had better CS in 6 and 18 cpd. In terms of aberrations, the IQ group had significantly (p < 0.05) lower spherical aberrations, root mean-square, and coma X and Y values with 6 mm pupil size than the SA group.Conclusions: In terms of refraction, no significant difference was found between these 2 types, but there was a difference in the quality of vision in photopic and mesopic conditions and also HOA. Those with reactive and dilated pupils, such as younger patients and night drivers, may be more satisfied with IQ aspherical lenses.     

非球面人工晶状体植入术后对比敏感度观察

目的:评价白内障超声乳化吸除联合非球面人工晶状体(intraocularlens,IOL)植入术后对比敏感度(contrast sensitivity,CS)的变化。方法:对45例(48眼)老年性白内障患者实施超声乳化吸除联合IOL植入术,24例(25眼)植入Z9001非球面IOL(AIOL);21例(23眼)植入AR40e单焦球面IOL(SI-OL)。术后3mo应用美国Stereo Optical公司产的OPTEC 6500P视功能测试系统的对比敏感度测试包分别在空间频率为1.5,3,6,12,18cpd的昼及夜照明条件下对手术眼进行有眩光和无眩光的对比敏感度检查。所得数据进行t检验。结果:术后3mo,AIOL组在大部分空间频率下CS普遍优于SIOL组,差异有统计学意义(P<0.05),在1.5cpd有眩光昼及夜照明条件,AIOL组的CS与SIOL组无统计学差异。结论:植入Z9001非球面IOL后,提高了患者的对比敏感度,明显改善患者的视觉质量.     

A novel standardized test system to evaluate dynamic visual acuity post trifocal or monofocal intraocular lens implantation: a multicenter study

ObjectivesTo compare the dynamic visual acuity (DVA) following implantation of trifocal with monofocal intraocular lenses (IOL) and using a novel test system.MethodsThe present research was a retrospective, multicenter clinical study. Two hundred and ten eyes of 149 patients that underwent cataract phacoemulsification and IOL implantation were enrolled. One hundred and ten eyes of patients received trifocal (AT LISA tri839MP, Carl Zeiss Meditec, Germany) and 100 eyes received monofocal (Tecnis ZCB00, Abbott, United States) lenses and were evaluated 3 months after implantation. Outcome measures included monocular uncorrected distance (UDVA), intermediate (UIVA) and near (UNVA) visual acuity and best corrected distance visual acuity (BCDVA; logMAR units); contrast sensitivity under photopic, mesopic, with glare conditions; and dynamic visual acuity using a self-developed system.ResultsThere was no statistically significant difference in baseline characteristics between groups. Monocular UDVA, UIVA, and UNVA were significantly better (all p < 0.001) in the trifocal IOL group, but not BCDVA. The trifocal IOL group showed better contrast sensitivity under photopic, mesopic, with or without glare conditions (p < 0.05) and statistically significantly better dynamic vision at 15, 30, 60, and 90 degrees per second (dps) compared with the monofocal group (all p < 0.001). The strength of positive association only between UIVA and dynamic visual acuity increased as the velocity increased, but not UDVA or UNVA.ConclusionsDiffractive trifocal IOL provides better postoperative full range vision acuity, contrast sensitivity, and dynamic vision compared with monofocal IOLs. And intermediate visual acuity is increasingly associated with DVA as the velocity increasing.Subject terms: Quality of life, Outcomes research     

The association between macular pigment optical density and visual function outcomes: a systematic review and meta-analysis

ObjectivesTo conduct a systematic review and meta-analysis on data related to macular pigment optical density (MPOD) and visual function in adults with healthy eyes.MethodsMEDLINE®, Cochrane, and Commonwealth of Agriculture Bureau abstracts databases were searched for English-language publications between 1946 and August 2018. Included studies examined correlation of MPOD and visual function in adults with healthy eyes at all timepoints and all designs, except for case–control, case reports, and reviews. Visual function outcomes of interest included photostress recovery, contrast sensitivity, visual acuity, glare sensitivity/disability, and dark adaptation. Random effects model meta-analyses combined study-level correlation (r).ResultsTwenty-two publications were included. In meta-analysis MPOD was found to be significantly correlated with contrast sensitivity at 30′ (two studies, summary r: 0.37; 95% CI 0.15, 0.56), and at 1° eccentricity with a spatial frequency of 7, 11, and 21 cpd (three studies, summary r: 0.31; 95% CI 0.06, 0.52), with photostress recovery at a 1° eccentricity with a moderate background, 10 cpd, and 16% contrast (two studies, summary r: −0.17; 95% CI −0.31, −0.02), and at 30′ (four studies, summary r: −0.57; 95% CI −0.78, −0.24), and with glare disability at 30′ eccentricity with a log scale at 460 nm (three studies, summary r = 0.47; 95% CI 0.32; 0.59). There were insufficient data for meta-analysis for other visual functions.ConclusionsOur review identifies a link between MPOD and visual function with significant correlations with photostress recovery, glare disability, and contrast sensitivity.Subject terms: Outcomes research, Epidemiology     

Photophobia measurement in intermittent exotropia using the contrast sensitivity test

Background

To assess the presence and extent of photophobia in children with intermittent exotropia (X[T]) using the contrast sensitivity test.

Methods

Fifty-eight children with X(T) and 34 normal controls were studied with the functional acuity contrast test. Each participant viewed the stimuli of contrast monocularly and binocularly under photopic and mesopic conditions, performed with and without glare. Photophobia was defined as a reduction of contrast sensitivity caused by glare light. We compared the photophobia of children with X(T) to that of normal controls, and to the photophobia 3 months after muscle surgery.

Results

With stimuli of glare, the contrast sensitivity of children with X(T) was suppressed at intermediate spatial frequencies under mesopic condition (p?=?0.006 for 6 cycles per degree [cpd], p?=?0.027 for 12 cpd), whereas that of normal controls showed no difference. It occurred when X(T) patients viewed targets binocularly, and significantly improved after strabismus surgery (p?=?0.003 at 6 cpd). The measured photophobia of X(T) was strongly correlated to the photophobia symptoms reported by parents (p?=?0.002).

Conclusions

The mesopic contrast sensitivity with glare can represent the photophobia of children with X(T). Contrast sensitivity may be a useful measure for monitoring symptoms related to X(T).     

三种非球面单焦点丙烯酸酯IOL植入术后暗视下视觉质量的观察

目的: 研究三种非球面丙烯酸酯人工晶状体(intraocularlens,IOL)植入术后患者在最佳矫正视力及暗视下(3cd/m2)对比敏感度(contrast sensitivity,CS)的变化,评价白内障超声乳化联合单焦点非球面丙烯酸酯IOL植入术后患者的视觉质量。方法: 选取符合条件的年龄相关性白内障患者77例90眼,2011-12/2012-11于我院行白内障超声乳化吸除联合IOL植入术,术前将患者随机分成三组,1组(25例30眼)植入疏水性染黄色丙烯酸酯IOL(HOYA),2组(28例30眼)植入亲水性丙烯酸酯IOL(Rayner)及3组(24例30眼)植入亲水性丙烯酸酯表面肝素处理IOL(XO)。所有患者于术后1,3mo均行最佳矫正视力(标准对数视力表)检查及暗视无眩光状态下的CS检查,所得结果进行统计学分析。结果: 患者术后1,3mo时,各组之间最佳矫正视力无明显统计学差异(P>0.05);患者1,3mo暗视无眩光状态下CS结果(标准化后的CS值:lgCS),三组患者之间CS值并无统计学差异(各组之间P>0.05),但HOYA组患者CS结果略下降。结论: 三组患者之间,术后1,3mo时最佳矫正视力及对暗视无眩光状态下CS结果无明显差异(P>0.05)。由于蓝光滤过型IOL对视网膜的潜在保护作用,因此植入染黄色滤过蓝光的IOL是可取的,特别是对儿童及青年白内障患者是必要的。     

Improving quality of vision with an anterior surface modified prolate intraocular lens: A prospective clinical trial

AIM: To compare the optical performance of the anterior surface modified prolate Tecnis Z9000 IOL with the standard 911A IOL in terms of contrast sensitivity outcomes. · METHODS: The Tecnis Z9000 silicone IOL shares the same basic characteristics with the 911A IOL including a 12.0mm overall diameter, 3-piece equiconvex 6.0mm optic and angulated cap C polyvinylidene fluoride haptics. This is a randomized prospective study that involved ten consecutive patients (20 eyes) with bilateral cataracts. Each patient underwent phacoemulsification and received randomly the Tecnis Z9000 IOL in one eye and the control (911A IOL) in the fellow eye within 6 weeks period of one another. Contrast sensitivity was measured after six postoperative weeks. The collected data were analyzed through using Mann Whitney U test. · RESULTS: The mean pre-operative best spectacle corrected Snellen visual acuity in the eyes that were randomly selected to receive the Tecnis IOL was 6/8.5 (0.70) and in the eye selected to receive the 911A IOL was 6/9.4(0.64). Postoperatively all 20 eyes achieved best corrected Snellen visual acuity of 6/6 (1.0). Postoperative contrast sensitivity testing showed statistically significant differences (P <0.05) between the two IOLs at 12 and 18 cpd under photopic, at 1.5 and 3 cpd under mesopic, and at 1.5 and 3 cpd under mesopic with glare conditions. · CONCLUSION: The Tecnis Z9000 IOL proved to have statistically significant superior contrast sensitivity to the 911A IOL at high spatial frequencies under photopic conditions and at low spatial frequencies under mesopic and mesopic with glare conditions.     

Comparison of pseudophakic visual quality in spherical and aspherical intraocular lenses

Objective: This study compares the visual performance of spherical and aspherical intraocular lenses (lOLs) by measuring higher-order aberration and contrast sensitivity (CS) values.Design: Prospective controlled study.Participants: Fifty-seven patients with age-related cataract (61 eyes).Methods: Patients were randomly allocated to 1 of 3 groups and implanted with either aspherical IOLs, Acrysof IQ (SN60WF) or Tecnis Z9001, or a spherical IOL, Acrysof Natural. Patients underwent routine examinations, including visual acuity, slit-lamp checks, and best-corrected visual acuity (BCVA), as well as measurement of higher-order aberrations and CS values, preoperatively and at 1 week, 1 month, and 2 months postoperatively.Results: All the patients had a BCVA better than 20/30 postoperatively. The spherical aberrations of the IQ group and Tecnis group were both lower than in the Natural (control) group (IQ: p <Tecnis: p < 0.05); there was no significant difference in coma and higher-order aberration. No statistically significant difference was found in spherical aberration, coma, or higher-order aberration between the IQ and Tecnis groups. Under glare conditions, the CS values of the 2 aspherical IOLs were obviously better (IQ: p < 0.05; Tecnis: p < 0.05) than the CS value of the spherical IOL group at low frequency (IQ: 6.3°, Tecnis: 4.0°); under non-glare conditions there was a significant difference in CS values between the aspherical IOL groups and the control group (IQ: p <Tecnis: p < 0.01) at low frequency (both 6.3°). There was no statistical difference between the IQ and the Tecnis groups with or without glare.Conclusions: An aspherical IOL can effectively reduce spherical aberration after cataract surgery, enhance CS values, and improve visual quality compared with traditional spherical IOLs for age-related cataract. However, there was no statistically significant difference in postoperative aberration and CS values between the Acrysof IQ and Tecnis Z9001 aspherical IOLs.     

Reduced visual function causes higher risks of traffic accidents

Background: This study was carried out to investigate the relationship between the frequency of traffic accidents and impaired vision. Materials and methods: Seven hundred and fifty-four drivers involved in accidents were recruited, in addition to 250 accident-free drivers similar in age and driving experience as an control group. The age distribution of the persons involved in traffic accidents (mean 56.3 years) was similar to that of the control group (mean 57.7 years), the difference was not statistically significant. Both groups underwent a complete ophthalmological examination. Results: All three types of accidents (night-time accidents, violations of right of way, accidents during an overtaking manoeuvre) had a statistically significantly higher incidence of reduced photopic visual acuity, mesopic vision and an increased sensitivity to glare. Some other visual functions were also abnormal, with differences according to the type of accident. In particular, there were noticeable differences between the control group and those who were involved in night-time accidents regarding mesopic vision and sensitivity to glare. Concerning mesopic vision, 15 % of the 261 persons involved in night-time accidents did not reach the contrast limit of 1 : 5; with glare, 20.7 % failed. In comparison 4 % of the control group reached this critical limit without glare and 7.6 % with glare. These differences are highly statistically significant. In contrast to these findings, many of the drivers involved in accidents assessed their own visual capability as “excellent”. Conclusions: The results of this study show that reduced mesopic vision and increased sensitivity to glare are accompanied by an increased risk of night-time accidents (for example, collisions with a non-illuminated obstacle). This emphasizes the importance of regular ophthalmological check-ups including visual functions such as mesopic vision and sensitivity to glare, which currently are not required by the traffic laws in Germany.      

Measuring contrast sensitivity under different lighting conditions: comparison of three tests.

PURPOSE: The purpose of this study was to evaluate three psychophysical tests for the measurement of contrast sensitivity (CS) and disability glare (DG) at different luminance levels. METHODS: In 60 eyes of 60 individuals (group 1: 20 healthy eyes of young individuals; group 2: 20 healthy eyes of elderly subjects; group 3: 20 eyes with nuclear cataract), CS with best correction was measured twice with the Frankfurt-Freiburg Contrast and Acuity Test System (FF-CATS) and the Functional Acuity Contrast Test (FACT, 1.5 cycles per degree [cpd]) at 167 cd/m2 and 0.167 cd/m2, and with the Pelli-Robson Chart (PRC) at 100 cd/m2 with and without glare. Repeatability of test and retest, and discriminative ability between the different subgroups, were assessed for CS values. RESULTS: Maximum CS values varied across tests. In all groups, highest CS values were obtained with the photopic FF-CATS. For FACT scores at 1.5 cpd, there was a ceiling effect for young subjects. CS scores obtained with the PRC were the lowest. The PRC had the best test-retest repeatability of all tests. Under mesopic conditions with glare, reliability was generally lower; the FF-CATS had the highest repeatability of the mesopic tests. The FF-CATS discriminated best between the different groups for all conditions. CONCLUSIONS: There are large discrepancies in the test results between CS testing methods, especially under different lighting conditions. Results from different CS tests are not interchangeable.     

Combination of Toric and multifocal intraocular lens implantation in bilateral cataract patients with unilateral astigmatism

AIM: To assess the binocular visual function in bilateral cataract patients with unilateral astigmatism after combined implantations of Toric with multifocal intraocular lens (IOL), and to compare with that of Toric and monofocal IOL implantation. METHODS: All the 30 patients with unilateral astigmatism suffered bilateral cataract were randomly divided into two groups: Toric plus multifocal IOL group and Toric plus monofocal IOL group. Uncorrected and corrected visual acuity at distance (5.0 m), intermediate distance (0.6 m), and near (0.33 m), contrast sensitivity, and stereopsis were assessed 6mo after surgery. Patients were also surveyed for visual disturbances and spectacle dependence. RESULTS: Binocular uncorrected visual acuity (LogMAR) of Toric/multifocal IOL eyes at distance, intermediate, near were 0.05±0.05, 0.24±0.10, and 0.14±0.06 respectively. The values of Toric plus monofocal IOL eyes were 0.06±0.07, 0.26±0.08, and 0.37±0.10 respectively. These values did not indicate significant differences between two groups with exception of near visual acuity. In the photopic condition (with or without glare), the contrast sensitivity of multifocal IOL eyes was significant lower than the monofocal IOL eyes in 18 cpd. In the mesopic condition, the contrast sensitivity of multifocal group was significant lower than monofocal group in 12 cpd, and in mesopic glare condition, this significant difference was found both in 6 cpd and 12 cpd. The stereopsis of Toric/multifocal IOL eyes decreased slightly (100±80 seconds of arc, t=2.222, P=0.136). Mean near vision for patient satisfaction was statistically significantly higher in Toric/multifocal IOL group patients versus than that in Toric/monofocal IOL group (80% vs 25.5%, P=0.000). Visual disturbance was not noticed in either group. CONCLUSION: Although the combination of Toric and multifocal IOL implantation results in compromising stereoacuity, it can still provide patients with high levels of spectacle freedom and good overall binocular visual acuity.     

非球面人工晶状体植入术后视觉质量对比分析

目的:评价3种非球面人工晶状体(AcrySof SN60WF、TecnisZ9001和KS-3Ai)植入术后的视觉质量。方法:采用前瞻性随机对照研究方法,收集我院老年性白内障手术患者88例126眼,平均年龄67.3±8.7岁,将入选患者按植入不同的人工晶状体(Intraocular lens,IOL)随机分为4组:AcrySofSN60WF(IQ)组(23例33眼)、TecnisZ9001组(23例33眼)、KS-3Ai组(20例29眼),SN60AT球面人工晶状体组为对照组(22例31眼)。术后随访3mo,观察指标:裸眼视力(uncorrected visual acuity,UCVA)及最佳矫正视力(best corrected visual acuity,BCVA),眼压,等效球镜度数,角膜Q值,瞳孔直径,6mm全眼球总高阶像差及四阶球差均方根值(root mean square,RMS),夜光、昼光及夜眩光3种视觉条件下的对比敏感度(contrast sensitivity,CS)。结果:术后各组的UCVA、BCVA、等效球镜度数和瞳孔直径均无统计学差异。总高阶像差和四阶球差RMS:非球面组低于球面组,差异具有统计学意义(P<0.05);非球面组间比较无统计学差异。术后角膜Q值与球差成正相关(r=0.183,P<0.05)。术后对比敏感度:与球面IOL相比,IQ,Tecnis可提高术后3种视觉条件下的CS,KS-3Ai可提高术后夜光、夜眩光两种视觉条件下的CS;非球面IOL组间比较,IQ组在昼光、夜眩光视觉条件下的CS好于Tecnis组和KS-3Ai组,TECNIS组和KS-3Ai组之间在3种视觉条件下均无统计学差异。结论:3种非球面IOL均可有效地减少术眼的总高阶像差和四阶球差。3种非球面IOL均可以提高术眼术后的CS,IQ组在昼光、夜眩光视觉条件下的CS与Tecnis组和KS-3Ai组相比较差异具有统计学意义,Tecnis组和KS-3Ai组之间在3种视觉条件下的CS均无统计学差异。     

Contrast sensitivity after implantation of a spherical versus an aspherical intraocular lens in biaxial microincision cataract surgery

PURPOSE: To determine whether implantation of a microincision intraocular lens (IOL) with a modified anterior surface, designed to compensate for the positive spherical aberration of the cornea in eyes of cataract patients, results in improved pseudophakic quality of vision in pseudophakic eyes after biaxial microincision phacoemulsification. SETTING: Department of Ophthalmology, Johannes Gutenberg-University, Mainz, Germany. METHODS: In a nonrandomized parallel cohort investigation, the visual performance of 52 eyes of 52 patients unilaterally implanted with the aspherical Acri.Smart 36 A IOL (Acri.Tec) were compared with those of 25 eyes of 25 age-matched patients unilaterally implanted with the spherical Acri.Smart 46 S IOL (Acri.Tec). Eight weeks after surgery, the following parameters were assessed: uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), pupil size under various illumination conditions, high-contrast and low-contrast visual acuities, photopic and mesopic contrast sensitivities, capsulorhexis size, and wavefront aberration of the cornea and eye. The primary clinical endpoint of the comparison was defined as the area under the cycles per degree (cpd) curve of the contrast sensitivity profile. RESULTS: The aspherical IOL group and the spherical IOL group did not differ in baseline characteristics. The median age was 71 years and 68% were women in the aspherical group versus 69 years and 62% women in the spherical group. The preoperative median UCVA was 20/80 in both groups. The UCVA, BCVA, pupil size, and capsulorhexis size were not statistically different between the 2 groups. Furthermore, no clinically relevant or statistically significant between-group differences were observed in the primary clinical endpoint. The median postoperative low mesopic contrast sensitivity without glare was 73 cpd in the aspherical group and 84 cpd in the spherical group (P = .624); a similar tendency was observed under high mesopic conditions (median 80 cpd and 83 cpd, respectively) (P = 1.000). Implantation of both IOL types resulted in a negative spherical aberration Z(4)(0), which was significantly different between the 2 groups (median -0.09 mum aspherical and -0.29 microm aspherical at a pupil size of 4.5 mm) (P<.001). CONCLUSIONS: No clinically relevant postoperative differences in contrast sensitivity were observed between the aspherical microincision IOL and the spherical equivalent model. The development of microincision IOLs, which fit through corneal incisions smaller than 2.0 mm and improve night-driving conditions (eg, reduction of glare), could optimize modern biaxial cataract surgery.     

人工晶状体前表面非球面化改良能够改善视觉质量

目的:根据对比敏感度结果比较前表面改良的非球面Tecnis Z9000 IOL和标准的911A IOL的光学性能.方法:Tecnis Z9000硅凝胶IOL和911A IOL具有共同的基本特征包括12mm总长度、三片直边双凸6mm的光学直径和成角的聚丙乙烯C襻.对连续10例双侧白内障患者(20眼)进行了随机前瞻研究,所有患者都接受了白内障超声乳化手术并随机于1眼植入Tecnis Z9000IOL,另1眼在术后6wk内植入911A IOL作为对照,术后6wk进行对比敏感度检查,所得数据采用秩和检验进行比较.结果:随机植入Tecnis IOL组的术前平均最佳Snellen矫正视力为6/8.5(0.70),植入911A I0L组为6/9.4(0.64),所有20眼术后最佳矫正视力都达到了6/6(1.0).术后对比敏感度分析发现两组在12和18 cpd(明视)、1.5和3 cpd(暮视)以及1.5和3 cpd(暮视伴眩光)均有统计学差异(P＜0.05)结论:Tecnis Z9000 I0L被证明其对比敏感度在明视高空间频率和暮视低空间频率方面均显著优于911A IOL.     

Ocular aberrations and contrast sensitivity after cataract surgery with AcrySof IQ intraocular lens implantation Clinical comparative study

PURPOSE: To determine whether implantation of an intraocular lens (IOL) with a modified posterior aspherical surface (AcrySof IQ, Alcon Surgical Laboratories) results in reduced ocular aberrations (spherical aberration) and improved contrast sensitivity after cataract surgery. SETTING: Brasilia Ophthalmologic Hospital, Brasilia, and Sao Geraldo Eye Hospital, Federal University of Minas Gerais, Belo Horizonte, Brazil. METHODS: In an intraindividual randomized prospective study of 25 patients with bilateral cataract, an IOL with a modified posterior surface (AcrySof IQ) was compared with a biconvex IOL with spherical surfaces (AcrySof Natural, Alcon). Ocular aberrations with a 5.0 mm and 6.0 mm pupil were measured with a Hartmann-Shack aberrometer. Quality of vision was measured by visual acuity and contrast sensitivity under mesopic and photopic conditions. All patients were followed for 3 months. RESULTS: There were no statistically significant differences between eyes in postoperative uncorrected and best corrected distance visual acuities after a follow-up of 1 month and 3 months. Postoperatively, there was a statistically significant between-group difference in contrast sensitivity under photopic conditions without glare at 18 cycles per degree (cpd) (P = .04) and under mesopic conditions without glare at all spatial frequencies (3 cpd, 6 cpd, 12 cpd, and 18 cpd; P = .03, P = .009, P = .003, and P = .003, respectively) and with glare at 3 cpd and 6 cpd (P = .001 and P = .02, respectively). The difference in higher-order aberration (HOA) values between groups was statistically significant with a 5.0 mm and 6.0 mm pupil, with the AcrySof IQ IOL inducing less HOA than the AcrySof Natural IOL. Eyes with an AcrySof IQ IOL also had statistically significant less spherical aberration than eyes with an AcrySof Natural IOL with both pupil diameters (P<.001). CONCLUSIONS: The AcrySof IQ IOL with a modified posterior surface induced significantly less HOA and spherical aberration than the AcrySof Natural IOL. Contrast sensitivity was better under mesopic conditions with the AcrySof IQ IOL.     

Supplementation with the carotenoids lutein or zeaxanthin improves human visual performance

BACKGROUND: Macular pigment (MP) is found in diurnal primate species when vision spans a range of ambient illumination and is mediated by cone and rod photoreceptors. The exact role of MP remains to be determined. In this study we investigate two new hypotheses for possible MP functions. OBJECTIVE: As MP absorption coincides partly with that of rhodopsin, MP may reduce rod signal effectiveness in the mesopic range, thus extend the usefulness of cone-mediated vision into the mesopic range. Forward light scatter in the eye can reduce retinal image contrast. If blue light contributes significantly to intraocular scatter, selective blue light absorption by MP could reduce the effects of scatter. DESIGN: We investigated 34 subjects from a carotenoid supplementation trial. The measurements included high mesopic contrast acuity thresholds (CATs), macular pigment optical density (MPOD), wavefront aberrations, and scattered light. The measurements were made after 6 months of daily supplementation with zeaxanthin (Z, OPTISHARP), lutein (L), a combination of the two (C), or placebo (P), and again after a further 6 months of doubled supplementation. RESULTS: The data reveal a trend toward lower CATs in all groups supplemented, with a statistically significant improvement in the lutein group (p = 0.001), although there was no correlation with MPOD. Light scattering in the eye and the root-mean-square wavefront aberrations show decreasing trends as a result of supplementation, but no correlation with MPOD. CONCLUSIONS: The results suggest that supplementation with L or Z increases MPOD at the fovea and at 2.5 degrees , and that supplementation can improve CATs at high mesopic levels and hence visual performance at low illumination.     

The macular pigment optical density spatial profile and increasing age

Purpose

To investigate the relationship between the central spatial profile of macular pigment optical density (MPOD) and increasing age in normal eyes.

Methods

Ninety-eight individuals (aged 19–71 years) with good visual acuity, free from ocular disease, and with clear ocular media participated. MPOD was measured at 0.25, 0.50, 1.00, and 1.75° eccentricity from the foveal centre using a heterochromatic flicker photometry based densitometer instrument.

Results

Linear regression analysis revealed that there was no statistically significant association between MPOD and increasing age for the group as a whole at 0.25, 0.50, and 1.00° eccentricity (p?>?0.05 for all eccentricities). There was a small but statistically significant positive association between increasing age and MPOD at 1.75° eccentricity (p?=?0.020), but age only accounted for 6 % of the variation in MPOD values. Fifteen percent of all participants had a non-exponential MPOD spatial profile.

Conclusion

There was no statistically significant relationship between MPOD and increasing age for three of the four locations measured. A significant proportion of individuals show an atypical MPOD spatial profile, indicating that studies on MPOD should ideally report information on the MPOD spatial profile rather than estimates from only one retinal location.     

Psychophysical impact and optical and morphological characteristics of symptomatic non-advanced cataract

Purpose

To investigate whether psychophysical, morphological, and/or optical characteristics of symptomatic non-advanced cataract are complementary to, or more appropriate than, visual acuity (VA) for the purposes of recording visual data that reflect subjective visual difficulty in patients with cataract that exhibit relative sparing of high contrast acuity (0.4 logarithm of minimal angle of resolution (logMAR) scale or better).

Methods

Eighty-two patients with symptomatic non-advanced cataract and no other ocular pathology were asked to complete a validated questionnaire, and to perform a series of visual function assessments including: corrected distance VA (CDVA); photopic and mesopic contrast sensitivity; photopic and mesopic glare disability (GD); reading acuity and reading speed; stereoacuity; and retinal sensitivity. Optical and morphological characteristics of the cataract were evaluated by lens optical density and by the Lens Opacities Classification System III, respectively. Correlations between questionnaire score and each of these measures were calculated.

Results

Statistically significant negative correlations were observed between the Rasch-scaled questionnaire score and mesopic GD (at 3 and 6 cycles per degree (cpd); r=−0.396 (P<0.01) and −0.451 (P<0.05), respectively) and between the Rasch-scaled questionnaire score and photopic GD (at 3 and 6 cpd; r=−0.328 (P<0.01) and −0.440 (P<0.01), respectively).

Conclusion

Symptomatic non-advanced cataract, in the presence of good CDVA, is associated with measurable subjective visual difficulty, best reflected in a decrease in mesopic and photopic GD (at medium spatial frequencies). CDVA does not reflect the patient''s visual dissatisfaction in such cases.     

The use of heterochromatic flicker photometry to determine macular pigment optical density in a healthy Australian population

Purpose

To establish the normal macular pigment density (MPOD) in a healthy adult Australian sample using heterochromatic flicker photometry (HFP).

Methods

Macular pigment density was measured using heterochromatic flicker photometry in a total of 201 subjects ranging in age from 21 to 84 years with healthy macula. Fifty-seven of the healthy subjects also completed a food-frequency dietary questionnaire. Best-corrected visual acuity (BCVA) was measured using logMAR, chart and macular morphological profiles were assessed using high-resolution integrated Fourier-domain optical coherence tomography (OCT).

Results

The average MPOD value was 0.41?±?0.20 (range 0.07–0.79). There was no statistically significant difference between values in the left and right eye, with good interocular agreement (0.41 vs 0.40, r?=?0.893, p?<?0.01). Age significantly predicted MPOD score (R ²?=?0.07, p?<?0.05). A subgroup analysis of patients who completed the dietary questionnaire revealed a close correlation between higher diet scores and higher MPOD (r?=?0.720 p?=?0.031). There was no effect of smoking, gender, or iris colour on MPOD values. There was no significant correlation between BCVA, macular OCT profiles, and MPOD.

Conclusion

Given that MPOD values are potentially affected by geographical variation, we have determined a mean MPOD value for healthy subjects in a population south of the equator, providing a reference point for future studies on Caucasian samples.