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Over the past decade, global screening time has increased, a trend intensified by the COVID-19 pandemic, leading to the integration of screens into daily life. Studies have documented the adverse effects of prolonged screening on ocular health and binocular vision, such as dry eye syndrome, blurry vision, headaches, myopia, and visual fatigue. However, it remains unclear if prolonged screening affects the development of colour vision defects. Objectives: This study aimed to determine the relationship between (a) prolonged screening and acquired colour vision deficiencies and (b) COVID-19 infection and acquired colour vision deficiencies. Methods: A population of 50 individuals with normal trichromatic vision, aged 20 to 30 years, with an average daily screening time of 516.7 min, was evaluated. Participants were initially screened using the Ishihara 32-plate Test to exclude those with congenital colour vision deficiencies. The Farnsworth–Munsell 100 Hue Test (FM100H) and Square Root Total Error Score (√TES) were used to evaluate acquired colour vision deficiencies under standardized conditions. The dataset underwent dual analysis: (1) detailed statistical scrutiny and (2) comparison of √TES values with historical data from 1982, 1991, 2001, and 2002. Results: The global group had a √TES (Mean ± SD) of 5.40 ± 1.58, the COVID-19 subgroup 5.46 ± 1.62, and the non-COVID-19 subgroup 5.32 ± 1.51. No significant differences were found between the √TES values from this population and those reported in previous studies. Statistical analysis showed no significant correlation between gender and COVID-19 infection with √TES values. Conclusions: Neither screening time nor COVID-19 infection appears to significantly impact the occurrence of permanently acquired colour vision deficiencies in individuals aged 20 to 30 years.

In this study, three psychophysical approaches that quantify the color discrimination capability of white light sources were systematically compared. A total of 11 light sources, five of 5500 K and six of 3000 K, were tested in two groups using three typical psychophysical methods including the Farnsworth‐Munsell100 Hue Test, real objects observation and color blocks comparison. The experimental results show that the examined approaches led to consistent conclusions on the color discrimination performance of lighting but differences in the robustness, complexity, and comprehensiveness of the methods were observed. Interestingly, sex difference in color discrimination was found to be influenced by visual judgment protocols. Based on this validation, methodological suggestions for future research on the color discrimination of lighting are proposed. [ABSTRACT FROM AUTHOR]

Using comparative and iterative analyses of three-component spectral power distributions, this work demonstrates the advantage of locating radiation about the prime color wavelengths (near 450, 530, and 610 nm) over the anti-prime color wavelengths (near 490, 570, and 650 nm) for the purpose of maximizing color discrimination as measured by the Total Light Source Error Score, Rd. To maximize color discrimination (minimize Rd) most effectively in the design of a three-component spectrum, locate the primaries about the prime color wavelengths and increase their spectral width up to a full-width at half-maximum of 60 nm, at which Rd is minimized. This work also details the internal logical consistency of quantifying color discrimination of a light source using Rd, whereby the color discrimination ability of the daylight spectrum is set as ideal color discriminator meant to be replicated, not exceeded. Such internal logical consistency does not exist with quantifying color discrimination using gamut area, where is it demonstrably simple to exceed the performance of daylight (i.e., Rg ≥ 100). [ABSTRACT FROM AUTHOR]

Purpose: to develop a screening strategy for the early diagnosis of primary open-angle glaucoma.Patients and Methods: 1 group — 250 patients with suspected glaucoma (42–75 years), 2 — 250 with the 1st stage primary open-angle glaucoma (42–61), 3 — 3,000 healthy persons (35 to 50). Surveys: visometry, tonometry iCare, biomicroscopy, gonioscopy, pachymeria, ophthalmoscopy with a high dioptric lens of 60 D, standard automated perimetry of the SITA-Standard and SITA-SWAP program, assessing the color sensitivity according to the Famsworth-Munsell 100 HueTes method.Results: 1 group — SITA-SWAP: MD -2,55±0,7 dB, PSD 2,46±1,15 dB. Mansell test: TES = 58.6±18.7 (p

The Farnsworth-Munsell 100 Hue Test, a test that measures an individual's hue discrimination ability, operates with the fundamental assumption that it is administered using a fixed, standard illuminant. This assumption is violated when the testing illuminant is changed—as is common when testing color discrimination ability of an illuminant—which likely causes a reordering of the caps in the test. To ensure that a participant is not falsely penalized for correctly responding to a hue transposition caused by the new testing light source, an adjusted error score is proposed that reconciles light source–induced hue transpositions and participant performance on the test. [ABSTRACT FROM AUTHOR]

Purpose: To develop and validate a new iPad-based color vision test (Optopad).Methods: A total of 341 student eyes were enrolled in a first comparative study between Optopad and the Isihara tests. In a second comparative study, Optopad vs. the Farnworth-Munsell test (FM 100H), a total of 66 adult eyes were included. Besides the agreement between tests, the correlation between FM 100H and Optopad outcomes were investigated. Multiple regression analysis was used to predict the total error score (TES) from contrast thresholds measured with the Optopad test.Results: The Ishihara and Optopad tests detected the same anomalous patients. Concerning FM 100H vs. Optopad, 10 subjects were diagnosed as anomalous with both tests, 3 mild anomalous cases based on TES were classified as normal with Optopad, and 2 anomalous subjects based on Optopad test showed normal TES values. Statistically significant correlations of TES and partial error red-green (PTESRG) with thresholds measured with the red-green Optopad stimuli were found. A multiple quadratic regression model was obtained relating TES and chromatic contrast values from Optopad (R2 = 0.855), with only 13 cases showing residuals of ≥ 25 units.Conclusions: The design and implementation of a chromatic contrast discrimination test has been carried out, with promising clinical results. This test seems to provide comparable outcomes to those obtained with Ishihara and FM 100H tests. [ABSTRACT FROM AUTHOR]

Background and objective: To determine the association between age-related macular degeneration (AMD) and color perception established by the Farnsworth–Munsell 100 hue (F–M 100) and maximum color contrast sensitivity (MCCS) tests. Materials and methods: We performed a case–control study, which comprised of 100 patients with AMD and 100 healthy controls. To test visual acuity (VA), a typical Snellen chart was used. The computerized F–M 100 and MCCS programs were used for color discrimination. Results: The results of VA, and the F–M 100 and MCCS tests in the healthy controls were statistically significantly better than in the patients with AMD (1.0 vs. 0.82 ± 0.16, P = 0.005; 87.39 ± 24.11 vs. 185.39 ± 74.43, P = 0.005; 1.33 ± 1.17 vs. 1.96 ± 0.46, P = 0.005, respectively). When VA was 1.0 in patients with AMD, the total error scores of the F–M 100 test and MCCS test compared with healthy persons were even worse (166.09 ± 66.57 vs. 87.39 ± 24.11, P = 0.002; 1.67 ± 0.92 vs. 1.33 ± 1.17, P = 0.001, respectively). Analysis of the results of patients with AMD compared to healthy controls showed the highest error score in the blue color range. Conclusions: The results of the color contrast sensitivity test decreased by half in patients with AMD compared with ophthalmologically healthy patients when they performed the F–M 100 test and by one and half when they performed a MCCS test in the blue color range.

AIM: To evaluate the performance of dominant eye (DE) for color vision discrimination ability among the medical students with normal color vision.CONCLUSION: The color vision discrimination performance ability was found prominent for DE. This superiority was attributed to higher sensitivityof the r/g local color spectral region. We conclude that DE has priority in r/g color spectral region, probably including inhibition of NDE.

We report the first case of vertical fixation by fibrin glue-assisted secondary posterior chamber intraocular lens implantation in a case of surgical aphakia. Advantages of vertical fixation are discussed.

Purpose: This study was designed to analyze the risk factors resulting in high intraocular pressure (IOP), which was accepted as IOP higher than 22 mmHg, following uncomplicated phacoemulsification. Materials and Methods: The records of 812 eyes of 584 patients who underwent uncomplicated phacoemulsification were evaluated. There were 330 men and 254 women ranging between the age of 26 and 89 years (65.4 ± 9.8 years). The preoperative, postoperative first day (day 1), first week (day 7), and first month (day 30) IOP values were analyzed. Data on history of diabetes, glaucoma, pseudoexfoliation (PXF), incision site, capsular staining with trypan blue, and surgeon were recorded. A multinomial regression analysis was performed to analyse the relationship of the factors with postoperative high IOP. Results: The mean IOP was 15.6 ± 4.3 mmHg preoperatively. Postoperatively that were changed to 19.7 ± 9.0 mmHg at day 1, 12.7 ± 4.5 mmHg at day 7, and 12.8 ± 3.7 mmHg at day 30. The factors such as surgeon, presence of PXF, diabetes, surgical incision site, and trypan blue were not related to the postoperative high IOP (P > 0.05, in all). The only factor that related to high IOP at all visits was glaucoma (P < 0.005). Conclusion: According to our results, preoperative diagnosis of glaucoma seems to be the only factor to affect the postoperative IOP higher than 22 mmHg.

Background: Optic pathway involvement in multiple sclerosis is frequently the initial sign in the disease process. In most clinical applications, pattern visual evoked potential (PVEP) is used in the assessment of optic pathway involvement. Objective: To question the value of PVEP against color vision assessment in the diagnosis of subclinical optic pathway involvement. Materials and Methods: This prospective, cross-sectional study included 20 multiple sclerosis patients without a history of optic neuritis, and 20 healthy control subjects. Farnsworth-Munsell (FM) 100-Hue testing and PVEPs to 60-min arc and 15-min arc checks by using Roland-Consult RetiScan® system were performed. P 100 amplitude, P 100 latency in PVEP and total error scores (TES) in FM 100-Hue test were assessed. Results: Expanded Disability Status Scale score and the time from diagnosis were 2.21 ± 2.53 (ranging from 0 to 7) and 4.1 ± 4.4 years. MS group showed significantly delayed P 100 latency for both checks (P < 0.001). Similarly, MS patients had significantly increased total error scores (TES) in FM-100 Hue (P < 0.001). The correlations between TESs and PVEP amplitudes / latencies were insignificant for both checks (P > 0.05 for all). 14 MS patients (70%) had an increased TESs in FM-100 Hue, 11 (55%) MS patients had delayed P 100 latency and 9 (45%) had reduced P 100 amplitude. The areas under the ROC curves were 0.944 for FM-100 Hue test, 0.753 for P 100 latency, and 0.173 for P 100 amplitude. Conclusions: Color vision testing seems to be more sensitive than PVEP in detecting subclinical visual pathway involvement in MS.

Aims: To investigate the effect of surgery type on the postoperative astigmatism in pterygium surgery. Settings and Design: Retrospective comparative clinical trial. Materials and Methods: Data of 240 eyes that underwent pterygium excision were investigated. Following removal of the pterygium, patients underwent 5 different types of surgeries: Conjunctival autograft with sutures (CAG-s) or fibrin glue (CAG-g), conjunctival rotational flap (CRF), or amniotic membrane transplantation with either suture (AMT-s) or with glue (AMT-g). The preoperative and postoperative keratometric measurements, evaluated using an automated keratorefractometer, were noted. Statistical Analysis: The overall changes in BCVA and astigmatic degree were evaluated using Wilcoxon signed rank test. The difference in astigmatic values between groups was calculated using one way analysis of variance (ANOVA). Results: The most commonly performed procedure was CAG-s (N = 115), followed by CAG-g (N = 53), CRF (N = 47), AMT-s (N = 15), and AMT-g (N = 10). Following surgery, astigmatic values decreased from 3.47 ± 2.50 D to 1.29 ± 1.07 D (P < 0.001, paired t test). The changes in astigmatism was significantly related to the preoperative size of the pterygium (ρ = 3.464, P = 0.005). The postoperative astigmatism correlated with preoperative astigmatism (ρ = 0.351, P < 0.001, Spearman correlation analysis). The changes in astigmatic values was not related to the method of surgery (P = 0.055, ANOVA). Conclusion: Pterygium results in high corneal astigmatism, which decreases to an acceptable level following excision. According to our study, the type of grafting as CAG, CRF or AMT or the use of suture or glue to fixate the graft does not have a significant effect on the change in astigmatism degree.

Aims: This study aims to investigate the effects of intravitreal octreotide on the growth factors, which have significant roles in the pathogenesis of proliferative vitreoretinopathy (PVR). Settings and Design: An experimental trial. Materials and Methods: 21 guinea pigs were randomly assigned to form 3 groups each including 7 animals. In group 1 (the control group), 0.2 ml saline solution was applied intravitreally in a location of 1.5 mm behind the limbus. In group 2 (the sham group), 0.07 IU dispase in 0.1 ml and 0.1 ml saline solution were applied via the same route. The guinea pigs in group 3 (the treatment group) were applied 0.07 IU dispase in 0.1 ml and 1 mg octreotide in 0.1 ml via the same route. Octreotide injection was applied twice during the period of 10 weeks of the experiment. At the end of the 10 weeks, eyes were enucleated and retinal homogenates were prepared. The platelet derivated growth factor (PDGF), insulin-like growth factor (IGF 1) and transforming growth factor (TGF ß) levels in homogenized retina tissue were measured by Enzyme Linked-Immuno-Sorbent Assay (ELISA) method. Statistical Analysis Used: Kruskal-Wallis variance analysis and Mann-Whitney U test. Results: In the treatment group, a significant decrease was observed in retinal PDGF levels (P < 0.01) while decreases in TGF ß and IGF 1 levels were not found to be significant (P > 0.05). Conclusions: Intravitreally applied octreotide at a dose of 1 mg has a highly strong effect on PDGF. This study suggests that intravitreal octreotide may suppress PVR development and that octreotide may merit investigation for PVR prophylaxis.

Primary iridociliary cysts can induce plateau iris configuration and angle closure glaucoma. We report a patient with bilateral, primary, ring-shaped, solitary iridociliary cysts. The right eye displayed normal intraocular pressure, oppositional iridocorneal angle closure, and healthy optic nerve head. The left eye had advanced chronic angle closure glaucoma. The management strategy varied between eyes and is discussed. This, to the best of our knowledge, is the first report of transscleral Diode laser application in an eye with a large iridociliary cyst.

In this case report, we present occurrence of bilateral angle closure glaucoma in a 9-year-old girl with geleophysic dysplasia. Bilateral YAG laser iridotomy was applied, but intraocular pressure (IOP) remained at high levels, necessitating bilateral trabeculectomy with mitomycin C. On her follow-up examinations for 3 years, IOP remained in the mid-20s with no need for further intervention or antiglaucoma medication. There are few reports describing the ocular findings of geleophysic dysplasia in literature. To our knowledge, this is the first case report describing an application of glaucoma surgery and its results at geleophysic dysplasia.

Objective: Use Bayes′ theorem to estimate the intraocular pressure (IOP) lowering effect of medical treatment initiated for glaucoma and determine if IOP comparisons to the baseline IOP of the same eye is clinically useful. Materials and Methods: The probability that treatment with prostaglandin is responsible for an observed 20% decrease in IOP with prostaglandin treatment was calculated using Bayes′ theorem using the following available information: the probability of a 20% decrease in IOP given treatment with prostaglandin, the probability of a treatment effect using prostaglandin and the overall probability of a 20% decrease in IOP. The calculations were repeated to account for a possible 2 mmHg overestimation of effect caused by measurement error in performing applanation tonometry. Results: The probability that treatment is responsible for an observed 20% decrease in IOP following initiation of treatment with a prostaglandin was 99%. After adjusting for measurement error this probability was 98%. Obtaining two IOP measurements marginally increased the probability. Conclusion: Following initiation of treatment with prostaglandin, Bayes′ theorem allows us to infer that treatment effect is the most likely explanation for an observed 20% decrease in IOP from the baseline; this inference remains even after adjusting for known measurement error. The high probability of a treatment effect is due to the high prior odds of treatment effect and the high likelihood ratio for prostaglandin producing such an effect. If data is available, similar calculations can be used for other percentage decreases, other medications and for the monocular trial.

The study was conducted to evaluate the intra-session repeatability of Tonopen AVIA (TPA). 180 eyes of 180 patients (50 eyes with glaucoma, 130 eyes of controls) were recruited for this observational study. The mean age of patients enrolled in the study was 43.9 ± 16.7 yrs (84 males, 96 females). Mean IOP recorded with Tonopen AVIA was 19.5 ± 9.5 mmHg, 19.4 ± 9.6 mmHg and 19.3 ± 9.2 mmHg, respectively in the first, second and third instances (P = 0.656). The intraclass correlation coefficient (ICC) ranged from 0.996 (95% CI: 0.956 - 0.998) for glaucoma subjects to 0.958 (95% CI: 0.934 - 0.975) for controls. The coefficient of variation in the study population ranged from 3.47% (glaucoma patients) to 8.10% (healthy controls), being 6.07% overall. The coefficient of repeatability varied between 2.96 (glaucoma patients), 3.35 (healthy controls) to 3.24 (overall). Thus, the Tonopen Avia shows good intrasessional repeatability of IOP in both glaucomatous patients and healthy subjects.

Background: Optic pathway involvement in multiple sclerosis is frequently the initial sign in the disease process. In most clinical applications, pattern visual evoked potential (PVEP) is used in the assessment of optic pathway involvement. Objective: To question the value of PVEP against color vision assessment in the diagnosis of subclinical optic pathway involvement. Materials and Methods: This prospective, cross- sectional study included 20 multiple sclerosis patients without a history of optic neuritis, and 20 healthy control subjects. Farnsworth-Munsell (FM) 100-Hue testing and PVEPs to 60-min arc and 15-min arc checks by using Roland-Consult RetiScan® system were performed. P100 amplitude, P100 latency in PVEP and total error scores (TES) in FM 100-Hue test were assessed. Results: Expanded Disability Status Scale score and the time from diagnosis were 2.21 ± 2.53 (ranging from 0 to 7) and 4.1 ± 4.4 years. MS group showed significantly delayed P100 latency for both checks (P < 0.001). Similarly, MS patients had significantly increased total error scores (TES) in FM-100 Hue (P < 0.001). The correlations between TESs and PVEP amplitudes / latencies were insignificant for both checks (P > 0.05 for all). 14 MS patients (70%) had an increased TESs in FM-100 Hue, 11 (55%) MS patients had delayed P100 latency and 9 (45%) had reduced P100 amplitude. The areas under the ROC curves were 0.944 for FM-100 Hue test, 0.753 for P100 latency, and 0.173 for P100 amplitude. Conclusions: Color vision testing seems to be more sensitive than PVEP in detecting subclinical visual pathway involvement in MS. [ABSTRACT FROM AUTHOR]

Background and purpose: Patients with essential tremor (ET) and Parkinson's disease (PD) may exhibit overlapping clinical features. Also, a growing number of non-motor features are being documented in ET. Color vision abnormalities, although well known to occur in PD, have not been studied extensively in ET. We assessed color vision in ET cases and controls. We furthermore assessed subgroups of ET cases with clinical features that might link them to PD (i.e., ET cases with a family history of PD, and ET cases with rest tremor) to determine whether these cases had greater color vision abnormalities than ET cases without those features. Methods: Participants were enrolled in a case-control study at Columbia University Medical Center. Color discrimination testing was performed using the Farnsworth-Munsell 100 Hue test. The total error score (TES) for the hue test was determined. Results: The TES was similar in 55 ET cases and 55 controls (144.6 ± 91.8 vs. 145.6 ± 96.6, P = 0.96). ET cases with rest tremor ( n = 8) were similar to ET cases without rest tremor ( n = 47) with respect to the TES (117.0 ± 73.4 vs. 149.3 ± 94.4, P = 0.36), as were ET cases with a family history of PD ( n = 9) versus without ( n = 46) (144.4 ± 57.0 vs. 144.6 ± 97.6, P = 0.996). Conclusions: Although a number of links exist between ET and PD, and non-motor features have been described in both, a color vision abnormality does not seem to be a feature of ET. [ABSTRACT FROM AUTHOR]

Decreased visual function is one of the non-motor dysfunctions of Parkinson's disease (PD). Recent evidences suggest that essential tremor (ET) is not 'pure' motor disorder and there is growing evidence that this disease is a multiple-system disorder. In some cases, it is difficult to differentiate ET from PD. In addition, there is considerable controversy regarding the relationship between PD and ET. The objective of this study was to compare color discrimination dysfunction amongst patients with PD and ET and to investigate the clinical relevance. Case-control comparisons of 54 patients with PD, 36 patients with ET, and 34 age-matched controls were performed. All cases underwent Farnsworth-Munsell 100 Hue test (FMT) and clinical assessments on medication. In addition, the association between color vision abnormalities and motor handicaps was investigated. There were significant differences in the total error scores (TES) of the FMT amongst the three groups; patients with the PD had higher TES than the patients with ET and the controls after adjustments for age. In addition, the motor symptom severity in PD correlated with the FMT abnormalities, especially with regard to the axial symptoms. The results of this study suggest that color vision abnormalities may be one of the non-motor clinical characteristics of PD-related dysfunction in contrast to ET. In addition, the severity of axial motor symptoms was closely related to visual dysfunction. Confirmation of these findings as well as the mechanisms underlying these results requires further study. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effects of smoking on colour vision with the Farnsworth-Munsell 100 Hue test. Materials and Methods: The Farnsworth-Munsell 100 Hue test (FHMT) was performed to evaluate colour vision in chronic smokers. This study included 80 subjects between 20 and 40 years of age who were routinely examined in our ophthalmology clinic and who agreed to participate in our study. All the subjects had a best corrected visual acuity of 10/10 with the Snellen visual acuity chart. The subjects were divided into two groups: group 1 included 50 smokers and group 2 included 30 nonsmokers. All participants underwent a complete ophthalmological examination including refraction with best-corrected visual acuity, tonometry, slit lamp biomicroscopy, dilated fundoscopy, and FMHT. Results: The FMHT score was 80±53.7 in group 1 versus 59.8±30.2 in group 2. The FMHT score in group 1 was significantly higher than that in group 2 (p<0.05). The mean number of cigarettes smoked per day was 14±8.7 and the mean duration of smoking was 8.6±5.3 years in group 1. A significant positive correlation was found between the FMHT score and the total number of cigarettes smoked per day (r=0.309, p<0.05); however, no significant correlation was observed between FMHT score and the duration of smoking (r=0.076, p>0.5). Conclusion: Total FMHT scores in smokers were significantly higher than those in nonsmokers and this score was positively correlated with the number of cigarettes smoked per day. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the effects of real and simulated age-related changes in crystalline lens yellowing on Farnsworth–Munsell (FM) 100 hue performance. Methods: FM 100 hue total and partial error scores (PES) were measured in a group of younger ( n = 10, mean age = 22.2 ± 2.65 years) and a group of older ( n = 10, mean age = 54.5 ± 2.64 years) normal observers along with psychophysical estimates of crystalline lens optical density and pupil size. Three younger observers underwent repeated FM 100 hue testing under a variety of simulated age-related lens yellowing conditions, using filters with well-defined transmittance properties which attempted to mimic the real age-related lens yellowing changes of the older group. Results: FM 100 hue total and PES were significantly higher in the older age group compared with the younger group ( p < 0.01). Lens density measures were significantly higher in the older age group compared with the young group ( p < 0.01), but showed less scatter than individual FM 100 hue error scores. Simulated lens yellowing in the three younger observers, equivalent to the level of that of the older observers, did not affect any of their FM 100 hue total or PES. Conclusions: Simulation of age-related lens yellowing in younger observers has little effect on FM 100 hue error score. A variety of other factors such as pupil size, background illuminaton level, iris colour and macular pigment density may contribute to the age-related increase in FM 100 hue scores. [ABSTRACT FROM AUTHOR]

Retinal detachment after ocular perforation related to local anesthesia is a common complication, which is usually associated with a poor prognosis despite complex vitreoretinal surgical procedures. We report a case of 62-year-old male with cataract surgery done 4 weeks back with nasal retinal detachment with a posterior break. Pneumatic retinopexy was performed and laser barrage of the breaks was done the next day when the retina got attached. A vision of 20/30 was achieved at the end of 2 months. To the best of our knowledge, this is a first case report in literature where pneumatic retinopexy was used to manage a retinal detachment caused by block-related perforation.

Our previous work revealed that, compared with other correlated colour temperatures (CCTs), a light source of 5500 K could arouse the strongest colour preference perception for blue jeans and provide the best colour discrimination capability for blue colours. In this study, we further investigated the impact of light sources on colour preference and colour discrimination using the same experimental objects (i.e. jeans and colour samples). Nine light sources of 5500 K were adopted and the illuminance level was set to 500 lx. Those lights were of different Duv values (-0.02 to 0.02, in 0.005 intervals) and similar colour rendering indices (CRIs, 87–92). Following a similar experimental protocol adopted in the earlier work, 30 subjects participated in the colour preference experiment while 24 observers joined the colour discrimination test (the Farnsworth-Munsell 100 Hue Test). The experimental results indicate that, once again, the colour preference and colour discrimination of lighting reached an optimum simultaneously, at a Duv value of -0.01. The hue shift and hue difference were proved to be closely associated with colour preference rating and colour discrimination scores, respectively. In addition, significant gender difference was again found, which had been reported in our latest work. [ABSTRACT FROM AUTHOR]