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  1. Fulltext The effects of induced optical blur on visual search performance and training
    Musa A, Lane AR, Ellison A
    Q J Exp Psychol (Hove), 2022 Feb;75(2):277-288.
    PMID: 34609221 DOI: 10.1177/17470218211050280
    Visual search is a task often used in the rehabilitation of patients with cortical and non-cortical visual pathologies such as visual field loss. Reduced visual acuity is often comorbid with these disorders, and it remains poorly defined how low visual acuity may affect a patient's ability to recover visual function through visual search training. The two experiments reported here investigated whether induced blurring of vision (from 6/15 to 6/60) in a neurotypical population differentially affected various types of feature search tasks, whether there is a minimal acceptable level of visual acuity required for normal search performance, and whether these factors affected the degree to which participants could improve with training. From the results, it can be seen that reducing visual acuity did reduce search speed, but only for tasks where the target was defined by shape or size (not colour), and only when acuity was worse than 6/15. Furthermore, searching behaviour was seen to improve with training in all three feature search tasks, irrespective of the degree of blurring that was induced. The improvement also generalised to a non-trained search task, indicating that an enhanced search strategy had been developed. These findings have important implications for the use of visual search as a rehabilitation aid for partial visual loss, indicating that individuals with even severe comorbid blurring should still be able to benefit from such training.
    Matched MeSH terms: Vision, Ocular*
  2. Abstracts of the 20th Asia Pacific Academy of Ophthalmology Congress, Kuala Lumpur, Malaysia, 27-31 March 2005
    Am J Ophthalmol, 2005 Apr;139(4 Suppl):S1-71.
    PMID: 16729358
    Matched MeSH terms: Vision, Ocular*
  3. Fulltext A parallel spatiotemporal saliency and discriminative online learning method for visual target tracking in aerial videos
    Aghamohammadi A, Ang MC, A Sundararajan E, Weng Ng K, Mogharrebi M, Banihashem SY
    PLoS One, 2018;13(2):e0192246.
    PMID: 29438421 DOI: 10.1371/journal.pone.0192246
    Visual tracking in aerial videos is a challenging task in computer vision and remote sensing technologies due to appearance variation difficulties. Appearance variations are caused by camera and target motion, low resolution noisy images, scale changes, and pose variations. Various approaches have been proposed to deal with appearance variation difficulties in aerial videos, and amongst these methods, the spatiotemporal saliency detection approach reported promising results in the context of moving target detection. However, it is not accurate for moving target detection when visual tracking is performed under appearance variations. In this study, a visual tracking method is proposed based on spatiotemporal saliency and discriminative online learning methods to deal with appearance variations difficulties. Temporal saliency is used to represent moving target regions, and it was extracted based on the frame difference with Sauvola local adaptive thresholding algorithms. The spatial saliency is used to represent the target appearance details in candidate moving regions. SLIC superpixel segmentation, color, and moment features can be used to compute feature uniqueness and spatial compactness of saliency measurements to detect spatial saliency. It is a time consuming process, which prompted the development of a parallel algorithm to optimize and distribute the saliency detection processes that are loaded into the multi-processors. Spatiotemporal saliency is then obtained by combining the temporal and spatial saliencies to represent moving targets. Finally, a discriminative online learning algorithm was applied to generate a sample model based on spatiotemporal saliency. This sample model is then incrementally updated to detect the target in appearance variation conditions. Experiments conducted on the VIVID dataset demonstrated that the proposed visual tracking method is effective and is computationally efficient compared to state-of-the-art methods.
    Matched MeSH terms: Vision, Ocular*
  4. The diabetic: his ocular complications and his visual prognosis
    SINGH P
    Med J Malaya, 1955 Sep;10(1):83-6.
    PMID: 13287497
    Matched MeSH terms: Vision, Ocular*
  5. Pixel-based skin colour detection techniques evaluation
    Alnned M. Mharib, Mohammad Hamiruce Marhaban, Abdul Rahman Ramli
    Pertanika Journal of Science & Technology, 2007;15(2):131-137.
    MyJurnal
    Skin detection has gained popularity and importance in the computer vision community. It is an essential step for important vision tasks such as the detection, tracking and recognition of face, segmentation of hand for gesture analysis, person identification, as well as video surveillance and filtering of objectionable web images. All these applications are based on the assumption that the regions of the human skin are already located. In the recent past, numerous techniques for skin colour modeling and recognition have been proposed. The aims of this paper are to compile the published pixel-based skin colour detection techniques to describe their key concepts and try to find out and summarize their advantages, disadvantages and characteristic features.
    Matched MeSH terms: Vision, Ocular
  6. Fulltext Visual acuity measured with luminance-modulated and contrast-modulated noise letter stimuli in young adults and adults above 50 years old
    Woi PJ, Kaur S, Waugh SJ, Hairol MI
    F1000Res, 2016;5:1961.
    PMID: 28184281 DOI: 10.12688/f1000research.9410.1
    The human visual system is sensitive in detecting objects that have different luminance level from their background, known as first-order or luminance-modulated (LM) stimuli. We are also able to detect objects that have the same mean luminance as their background, only differing in contrast (or other attributes). Such objects are known as second-order or contrast-modulated (CM), stimuli. CM stimuli are thought to be processed in higher visual areas compared to LM stimuli, and may be more susceptible to ageing. We compared visual acuities (VA) of five healthy older adults (54.0±1.83 years old) and five healthy younger adults (25.4±1.29 years old) with LM and CM letters under monocular and binocular viewing. For monocular viewing, age had no effect on VA [F(1, 8)= 2.50, p> 0.05]. However, there was a significant main effect of age on VA under binocular viewing [F(1, 8)= 5.67, p< 0.05].  Binocular VA with CM letters in younger adults was approximately two lines better than that in older adults. For LM, binocular summation ratios were similar for older (1.16±0.21) and younger (1.15±0.06) adults. For CM, younger adults had higher binocular summation ratio (1.39±0.08) compared to older adults (1.12±0.09). Binocular viewing improved VA with LM letters for both groups similarly. However, in older adults, binocular viewing did not improve VA with CM letters as much as in younger adults. This could reflect a decline of higher visual areas due to ageing process, most likely higher than V1, which may be missed if measured with luminance-based stimuli alone.
    Matched MeSH terms: Vision, Ocular
  7. Fulltext The impact of luminance contrast on attention and memory
    Yap SL, Tan XB, Tan CS
    Jurnal Psikologi Malaysia, 2017;31:90-98.
    Previous studies have found that luminance contrast may enhance attention and attention is positively correlated with memory. However, little attention has been given to understand the impact of luminance contrast on memory. The present study attempts to address this gap by examining the effect of luminance contrast on attention and memory. A total of 159 undergraduates were randomly assigned to three luminance contrast conditions (high vs. moderate vs. low) and were administered a modified d2 test and modified words memory test. Multivariate analysis of variance showed significant effect of luminance contrast on memory performance. Participants in the high and moderate luminance contrast groups recalled more words than counterparts in the low contrast group. However, the effect of luminance contrast on attention was not significant, though planned comparison found that high contrast group scored higher than low contrast group. The findings not only shed light on improvement of memory but also have implication for design and marketing and consumer behaviours study.
    Matched MeSH terms: Vision, Ocular
  8. Effects of short-term VDT usage on visual functions
    Yeow PT, Taylor SP
    Optom Vis Sci, 1989 Jul;66(7):459-66.
    PMID: 2771333
    An on-site comparative study was carried out on the effects of video display terminal (VDT) and non-VDT work on visual functions in two working populations in the same office environment. Both continuous VDT usage in a training situation over a few days and intermittent VDT usage in a normal working situation were assessed and particular attention paid to their effects on the refractive error of different refractive groups and for different age populations. Other visual functions measured were visual acuity (VA), accommodation, and convergence. Results show that VDT work does not have a significantly greater effect on visual function than non-VDT work.
    Matched MeSH terms: Vision, Ocular/physiology*; Vision, Ocular/radiation effects
  9. Fulltext The causes of low vision and pattern of prescribing at UKM low vision clinic
    Rokiah Omar, Knight, Victor Feizal, Zainora Mohammed
    Jurnal Sains Kesihatan Malaysia, 2008;6(2):55-64.
    MyJurnal
    When medical and surgical intervention cannot alleviate all of the impairments resulting from diseases of the eye, visual rehabilitation can help reduce the disability and increase the quality of life. Data from 169 patients seen at the UKM Low Vision Clinic (UKM LVC) over the past 2 years were examined and analysed. The age ranged from 6 to 87 years of age. The main cause of ocular pathological categories was conduction (63.9%), media (24.9%) and congenital (11.2%) related problems. The main causes of low vision at UKM LVC were congenital cataract, retinitis pigmentosa, glaucoma, cataract and diabetic retinopathy. 84% of these patients received low vision devices to improve their near or/and distance vision. The most common optical devices dispensed at UKM LVC were near high addition spectacle, hand magnifiers and stand magnifiers. Medical, vision care and rehabilitation professionals working together can offer a comprehensive treatment plan for the visually impaired, offering these patients the very best services to increase their quality of life.
    Matched MeSH terms: Vision, Ocular
  10. Fulltext Posterior Vitreous Detachment Precipitated by Yoga
    Chong SY, Fhun LC, Tai E, Chong MF, Sonny Teo KS
    Cureus, 2018 Jan 24;10(1):e2109.
    PMID: 29581921 DOI: 10.7759/cureus.2109
    Yoga has recently been touted as a means to improve physical and mental well-being. However, no form of exercise is without its risks. A 32-year-old Chinese female with moderate myopia complained of right eye sudden onset of floaters and mild blurring of vision after the head-down posture. The visual acuity was 6/12 in the right eye and 6/9 in the left eye. A right eye fundus examination showed posterior vitreous detachment, with a small blood clot located at the inferior margin of the optic disc. The patient was diagnosed with right eye vitreous hemorrhage secondary to acute posterior vitreous detachment and was managed conservatively. Acute changes in posture, especially between an upright and a head-down position, may cause acute posterior vitreous detachment. As yoga practitioners may be required to assume this head-down position, myopic patients should be warned of the possible ocular complications of this exercise.
    Matched MeSH terms: Vision, Ocular
  11. Fulltext Exposure to foods' non-taste sensory properties. A nursery intervention to increase children's willingness to try fruit and vegetables
    Dazeley P, Houston-Price C
    Appetite, 2015 Jan;84:1-6.
    PMID: 25218879 DOI: 10.1016/j.appet.2014.08.040
    Activities that engage young children with the sensory properties of foods are popular with nursery schools, despite the lack of evidence for their efficacy in increasing children's consumption of healthy foods. This study provides the first empirical exploration of the effectiveness of a non-taste sensory activity program in a nursery school setting. Ninety-two children aged between 12 and 36 months were allocated either to an intervention group, who took part in looking, listening, feeling and smelling activities with unusual fruits and vegetables every day for 4 weeks, or to a non-intervention control group. In a subsequent mealtime taste test, children touched and tasted more of the vegetables to which they had been familiarized in their playtime activities than of a matched set of non-exposed foods. The results demonstrate that hands-on activities with unfamiliar fruits and vegetables can enhance children's willingness to taste these foods, and confirm the potential for such activities to support healthy eating initiatives.
    Matched MeSH terms: Vision, Ocular*
  12. Relating vision status to academic achievement among year-2 school children in Malaysia
    Chen AH, Bleything W, Lim YY
    Optometry, 2011 May;82(5):267-73.
    PMID: 21524597 DOI: 10.1016/j.optm.2011.02.004
    Vision affects daily activities, but of particular importance is the impact upon the learning process. Many studies have been conducted to establish the relationship between vision problems and academic performance. The results are varied, however, and suggest additional research is needed with particular care given to study design.
    Matched MeSH terms: Vision, Ocular*
  13. Gait disorder rehabilitation using vision and non-vision based sensors: a systematic review
    Ali A, Sundaraj K, Ahmad B, Ahamed N, Islam A
    Bosn J Basic Med Sci, 2012 Aug;12(3):193-202.
    PMID: 22938548
    Even though the amount of rehabilitation guidelines has never been greater, uncertainty continues to arise regarding the efficiency and effectiveness of the rehabilitation of gait disorders. This question has been hindered by the lack of information on accurate measurements of gait disorders. Thus, this article reviews the rehabilitation systems for gait disorder using vision and non-vision sensor technologies, as well as the combination of these. All papers published in the English language between 1990 and June, 2012 that had the phrases "gait disorder", "rehabilitation", "vision sensor", or "non vision sensor" in the title, abstract, or keywords were identified from the SpringerLink, ELSEVIER, PubMed, and IEEE databases. Some synonyms of these phrases and the logical words "and", "or", and "not" were also used in the article searching procedure. Out of the 91 published articles found, this review identified 84 articles that described the rehabilitation of gait disorders using different types of sensor technologies. This literature set presented strong evidence for the development of rehabilitation systems using a markerless vision-based sensor technology. We therefore believe that the information contained in this review paper will assist the progress of the development of rehabilitation systems for human gait disorders.
    Matched MeSH terms: Vision, Ocular
  14. Ergonomics improvements of the visual inspection process in a printed circuit assembly factory
    Yeow PH, Sen RN
    Int J Occup Saf Ergon, 2004;10(4):369-85.
    PMID: 15598361
    An ergonomics improvement study was conducted on the visual inspection process of a printed circuit assembly (PCA) factory. The process was studied through subjective assessment and direct observation. Three problems were identified: operators' eye problems, insufficient time for inspection and ineffective visual inspection. These problems caused a huge yearly rejection cost of US 298,240 dollars, poor quality, customer dissatisfaction and poor occupational health and safety. Ergonomics interventions were made to rectify the problems: reduced usage of a magnifying glass, the use of less glaring inspection templates, inspection of only electrically non-tested components and introduction of a visual inspection sequence. The interventions produced savings in rejection cost, reduced operators' eye strain, headaches and watery eyes, lowered the defect percentage at customers' sites and increased the factory's productivity and customer satisfaction.
    Matched MeSH terms: Vision, Ocular
  15. Fulltext Double Eyelid Tape Wear Affects Anterior Ocular Health among Young Adult Women with Single Eyelids
    Yong PT, Arif N, Sharanjeet-Kaur S, Hairol MI
    Int J Environ Res Public Health, 2020 10 22;17(21).
    PMID: 33105550 DOI: 10.3390/ijerph17217701
    Many East Asians apply double eyelid tape to create the double eyelid effect temporarily as a means of increasing their beauty. This study evaluated the effects of four-week wear of double eyelid tape on anterior ocular health in young adult women with single eyelids. Twenty-nine participants who met the inclusion criteria were recruited. The participants' anterior ocular health was examined including blinking characteristics (blink pattern and blink rate), ocular surface health (presence of corneal abrasion, corneal staining, conjunctival staining, corneal curvatures, meibomian gland dysfunction), tear break up time, intraocular pressure, and subjective comfort level. Participants were required to apply the double eyelid tape for at least eight hours a day and five days a week for four weeks. The parameters were re-measured at the end of each week. There was a significant increase in conjunctival staining, corneal staining, and meibomian gland dysfunction, with a significant reduction in tear break-up time and intraocular pressure. By week 3, all participants had incomplete blinks. There was no significant change in symptoms and subjective comfort level reported. Therefore, patients and eye care practitioners should be aware of the potential implications of double eyelid tape wear on ocular health, with no significant change in subjective comfort.
    Matched MeSH terms: Vision, Ocular
  16. Fulltext Sequelae of neglected senile cataract
    Azhany Y, Hemalatha C, Nani D, Rosediani M, Liza-Sharmini A
    Malays Fam Physician, 2013;8(1):33-7.
    PMID: 25606266 MyJurnal
    Cataract is the most common cause of blindness in the world. An attack of phacolytic and phacomorphic glaucoma as a result of neglected cataract constitutes a medical emergency that must be addressed immediately. Ocular emergencies such as these is challenging for the surgeon with guarded or poor prognosis. We describe the presentation, management and prognosis of three cases of phacomorphic and phacolytic glaucoma. All three patients underwent aggressive management of intraocular pressure. Despite successful cataract operation with implantation of intraocular lens, there was only mild improvement of the vision. Optic nerve and pupil functions were permanently affected following the insult. Phacomorphic and phacolytic glaucoma present a very challenging problem to the surgeon with poor visual outcome. Public health education and awareness are important and health workers should encourage patients with cataract to seek early treatment for better prognosis.
    Matched MeSH terms: Vision, Ocular
  17. Fulltext Philanthotoxin-343 attenuates retinal and optic nerve injury, and protects visual function in rats with N-methyl-D-aspartate-induced excitotoxicity
    Fazel MF, Abu IF, Mohamad MHN, Agarwal R, Iezhitsa I, Bakar NS, et al.
    PLoS One, 2020;15(7):e0236450.
    PMID: 32706792 DOI: 10.1371/journal.pone.0236450
    Retinal ganglion cell (RGC) loss and optic neuropathy, both hallmarks of glaucoma, have been shown to involve N-methyl-D-aspartate receptor (NMDAR)-mediated excitotoxicity. This study investigated the neuroprotective effects of Philanthotoxin (PhTX)-343 in NMDA-induced retinal injury to alleviate ensuing visual impairments. Sprague-Dawley rats were divided into three; Group I was intravitreally injected with phosphate buffer saline as the control, Group II was injected with NMDA (160 nM) to induce retinal excitotoxic injury, while Group III was injected with PhTX-343 (160 nM) 24 h prior to excitotoxicity induction with NMDA. Rats were subjected to visual behaviour tests seven days post-treatment and subsequently euthanized. Rat retinas and optic nerves were subjected to H&E and toluidine blue staining, respectively. Histological assessments showed that NMDA exposure resulted in significant loss of retinal cell nuclei and thinning of ganglion cell layer (GCL). PhTX-343 pre-treatment prevented NMDA-induced changes where the RGC layer morphology is similar to the control. The numbers of nuclei in the NMDA group were markedly lower compared to the control (p<0.05). PhTX-343 group had significantly higher numbers of nuclei within 100 μm length and 100 μm2 area of GCL (2.9- and 1.7-fold, respectively) compared to NMDA group (p<0.05). PhTX-343 group also displayed lesser optic nerve fibres degeneration compared to NMDA group which showed vacuolation in all sections. In the visual behaviour test, the NMDA group recorded higher total distance travelled, and lower total immobile time and episodes compared to the control and PhTX-343 groups (p<0.05). Object recognition tests showed that the rats in PhTX-343 group could recognize objects better, whereas the same objects were identified as novel by NMDA rats despite multiple exposures (p<0.05). Visual performances in the PhTX-343 group were all comparable with the control (p>0.05). These findings suggested that PhTX-343 inhibit retinal cell loss, optic nerve damage, and visual impairments in NMDA-induced rats.
    Matched MeSH terms: Vision, Ocular/drug effects
  18. Fulltext Catquest-9SF questionnaire: validation of Malay and Chinese-language versions using Rasch analysis
    Adnan TH, Mohamed Apandi M, Kamaruddin H, Salowi MA, Law KB, Haniff J, et al.
    Health Qual Life Outcomes, 2018 Jan 05;16(1):5.
    PMID: 29304817 DOI: 10.1186/s12955-017-0833-3
    BACKGROUND: Catquest questionnaire was originally developed in Swedish to measure patients' self-assessed visual function to evaluate the benefit of cataract surgery. The result of the Rasch analysis leading to the creation of the nine-item short form of Catquest, (Catquest-9SF), and it had been translated and validated in English. The aim is therefore to evaluate the translated Catquest-9SF questionnaire in Malay and Chinese (Mandarin) language version for measuring patient-reported visual function among cataract population in Malaysia.

    METHODS: The English version of Catquest-9SF questionnaire was translated and back translated into Malay and Chinese languages. The Malay and Chinese translated versions were self-administered by 236 and 202 pre-operative patients drawn from a cataract surgery waiting list, respectively. The translated Catquest-9SF data and its four response options were assessed for fit to the Rasch model.

    RESULTS: The Catquest-9SF performed well in the Malay and Chinese translated versions fulfilling all criteria for valid measurement, as demonstrated by Rasch analysis. Both versions of questionnaire had ordered response thresholds, with a good person separation (Malay 2.84; and Chinese 2.59) and patient separation reliability (Malay 0.89; Chinese 0.87). Targeting was 0.30 and -0.11 logits in Malay and Chinese versions respectively, indicating that the item difficulty was well suited to the visual abilities of the patients. All items fit a single overall construct (Malay infit range 0.85-1.26, outfit range 0.73-1.13; Chinese infit range 0.80-1.51, outfit range 0.71-1.36), unidimensional by principal components analysis, and was free of Differential Item Functioning (DIF).

    CONCLUSIONS: These results support the good overall functioning of the Catquest-9SF in patients with cataract. The translated questionnaire to Malay and Chinese-language versions are reliable and valid in measuring visual disability outcomes in the Malaysian cataract population.

    Matched MeSH terms: Vision, Ocular/physiology*
  19. Linked color imaging improves the visibility of various featured colorectal polyps in an endoscopist's visibility and color difference value
    Yoshida N, Naito Y, Yasuda R, Murakami T, Hirose R, Ogiso K, et al.
    Int J Colorectal Dis, 2017 Sep;32(9):1253-1260.
    PMID: 28725959 DOI: 10.1007/s00384-017-2855-z
    PURPOSE: Linked color imaging (LCI) by laser endoscopy is a novel narrow band light observation. In this study, we analyzed the efficacy of LCI for improving the various featured colorectal polyp's visibility utilizing a subjective endoscopist's visibility scoring and objective color difference (CD) value.

    METHODS: We retrospectively reviewed two pictures both with white light (WL) and LCI for 54 consecutive neoplastic polyps 2-20 mm in size. All pictures were evaluated by four endoscopists according to a published polyp visibility score from four (excellent visibility) to one (poor visibility). Additionally, we calculated CD value between each polyp and surrounding mucosa in LCI and WL using an original software.

    RESULTS: The mean polyp visibility scores of LCI (3.11 ± 1.05) were significantly higher than those of WL (2.50 ± 1.09, P 

    Matched MeSH terms: Vision, Ocular*
  20. An ergonomics study of a semiconductors factory in an IDC for improvement in occupational health and safety
    Bin WS, Richardson S, Yeow PH
    Int J Occup Saf Ergon, 2010;16(3):345-56.
    PMID: 20828490
    The study aimed to conduct an ergonomic intervention on a conventional line (CL) in a semiconductor factory in Malaysia, an industrially developing country (IDC), to improve workers' occupational health and safety (OHS). Low-cost and simple (LCS) ergonomics methods were used (suitable for IDCs), e.g., subjective assessment, direct observation, use of archival data and assessment of noise. It was found that workers were facing noise irritation, neck and back pains and headache in the various processes in the CL. LCS ergonomic interventions to rectify the problems included installing noise insulating covers, providing earplugs, installing elevated platforms, slanting visual display terminals and installing extra exhaust fans. The interventions cost less than 3 000 USD but they significantly improved workers' OHS, which directly correlated with an improvement in working conditions and job satisfaction. The findings are useful in solving OHS problems in electronics industries in IDCs as they share similar manufacturing processes, problems and limitations.
    Matched MeSH terms: Vision, Ocular
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