Displaying publications 1 - 20 of 45 in total

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  1. Chen AH, Aziz A
    Malays J Med Sci, 2003 Jan;10(1):90-4.
    PMID: 23365507
    The purpose of this study was to investigate the relationship between heterophoria and refractive error. Thirty-six subjects (11 myopes, 25 emmetropes) participated in this study. Heterophoria was measured with the Free-Space Phoria Card at five different viewing distances (25cm, 33cm, 50cm, 100cm and 300cm). Regardless of the types of heterophoria, the amount of heterophoria reduced towards orthophoric position with increasing viewing distance. Emmetropes and myopes did not show any significant difference in the degree of heterophoria at different viewing distances (F = 0.30, p>0.05) or in the type of heterophoria (χ(2) = 2, p>0.05).
    Matched MeSH terms: Refractive Errors
  2. Chung KM
    Optom Vis Sci, 1999 Feb;76(2):121-6.
    PMID: 10082059
    The clinical significance of fundus magnification produced during direct ophthalmoscopy of the corrected eye has not been fully established. Based on paraxial ray tracing, fundus magnification (M) can be defined by a simple equation, M = (K'/4) x (Fs/K), where K' is the dioptric axial power of the eye, Fs is the correcting thin lens power and K is the ocular ametropia. Refractive myopes produce greater fundus magnification than axial myopes, whereas refractive hyperopes produce lower fundus magnification than axial hyperopes. If we assume 15 x fundus magnification as our standard magnification for an emmetropic reduced eye, then wearing glasses or putting the focusing lens at or close to the anterior focus of the eye is able to achieve the standard magnification for axial myope and axial hyperope, whereas wearing contact lenses is able to achieve the standard magnification for refractive myope and refractive hyperope. Vertex distance has greater influence on fundus magnification produced during direct ophthalmoscopy than other funduscopic techniques. In conclusion, the newly defined formula has clinical applications during direct ophthalmoscopy.
    Matched MeSH terms: Refractive Errors/pathology*; Refractive Errors/therapy*
  3. Allinjawi K, Sharanjeet-Kaur SK, Akhir SM, Mutalib HA
    F1000Res, 2016;5:2742.
    PMID: 28163898 DOI: 10.12688/f1000research.9971.1
    Aim: The purpose of this study was to compare the changes in relative peripheral refractive error produced by two different designs of progressive soft contact lenses in myopic schoolchildren. Methods: Twenty-seven myopic schoolchildren age between 13 to 15 years were included in this study. The measurements of central and peripheral refraction were made using a Grand-Seiko WR-5100K open-field autorefractometer without correction (baseline), and two different designs of progressive contact lenses (PCLs) (Multistage from SEED & Proclear from Cooper Vision) with an addition power of +1.50 D. Refractive power was measured at center and at eccentricities between 35º temporal to 35º nasal visual field (in 5º steps). Results: Both PCLs showed a reduction in hyperopic defocus at periphery. However, this reduction was only significant for the Multistage PCL (p= 0.015), (Proclear PCL p= 0.830).  Conclusion: Multistage PCLs showed greater reduction in peripheral retinal hyperopic defocus among myopic schoolchildren in comparison to Proclear PCLs.
    Matched MeSH terms: Refractive Errors
  4. Shah Farez Othman, Nizam Tamchek, Farah Diana Muhammad, Shah Farez Othman, Shah Farez Othman, Mohd Hafidz Ithnin
    MyJurnal
    Current trend shows that the eye modelling is based on the emmetropic eye taken its ocular optical components value from the population-based studies. However, no studies have been done to study the effect of aberration of myopic refractive error by modelling the eye using the parameters from ocular biometrics and ray tracing method. The objective of the present study was to determine the spot diagram (SPD) profile of myopic refractive error using eye modelling and ray tracing technique. Three eye models had been successfully modeled in Zemax software, namely, emmetropic Liou and Brennan, myopic Liou and Brennan, corrected myopic Liou and Brennan. The optical performance of the eye models were tested using the SPD profile. The ray distribution from the analysis of SPD of myopic Liou and Brennan eye was larger compared to the emmetropic model. In comparison with the emmetropic Liou and Brennan model, for the blue wavelength, the RMS spot radius for the corrected version was increased. However, the RMS values were decreased for green and red wavelengths. For the corrected myopic version of Liou and Brennan, in comparison with its emmetropic model, the Airy disc diameter increased with the increment of wavelengths. It was found that the Airy disc diameter accuracy were higher for the blue, green and red wavelengths. Although the accuracy values were in a positive sign, for Airy disc diameter, the smaller value indicates a diffraction-limited condition.
    Matched MeSH terms: Refractive Errors
  5. Sharanjeet-Kaur, Norlaila MD, Chung KM, Azrin EA, Boo NY, Ong LC
    Clin Ter, 2011;162(6):517-9.
    PMID: 22262320
    A cross-sectional study was undertaken to determine and compare the refractive status of premature children without retinopathy of prematurity (ROP) and full term children below the age of three years.
    Matched MeSH terms: Refractive Errors/epidemiology*
  6. Chandran S, Ooi Eu-sen V
    Med J Malaya, 1971 Mar;25(3):193-7.
    PMID: 4253246
    Matched MeSH terms: Refractive Errors/epidemiology*
  7. Hashim SE, Tan HK, Wan-Hazabbah WH, Ibrahim M
    Ann Acad Med Singap, 2008 Nov;37(11):940-6.
    PMID: 19082201
    INTRODUCTION: Refractive error remains one of the primary causes of visual impairment in children worldwide, and the prevalence of refractive error varies widely. The objective of this study was to determine the prevalence of refractive error and study the possible associated factors inducing refractive error among primary school children of Malay ethnicity in the suburban area of Kota Bharu, Kelantan, Malaysia.

    MATERIALS AND METHODS: A school-based cross-sectional study was performed from January to July 2006 by random selection on Standard 1 to Standard 6 students of 10 primary schools in the Kota Bharu district. Visual acuity assessment was measured using logMAR ETDRS chart. Positive predictive value of uncorrected visual acuity equal or worse than 20/40, was used as a cut-off point for further evaluation by automated refraction and retinoscopic refraction.

    RESULTS: A total of 840 students were enumerated but only 705 were examined. The prevalence of uncorrected visual impairment was seen in 54 (7.7%) children. The main cause of the uncorrected visual impairment was refractive error which contributed to 90.7% of the total, and with 7.0% prevalence for the studied population. Myopia is the most common type of refractive error among children aged 6 to 12 years with prevalence of 5.4%, followed by hyperopia at 1.0% and astigmatism at 0.6%. A significant positive correlation was noted between myopia development with increasing age (P <0.005), more hours spent on reading books (P <0.005) and background history of siblings with glasses (P <0.005) and whose parents are of higher educational level (P <0.005). Malays in suburban Kelantan (5.4%) have the lowest prevalence of myopia compared with Malays in the metropolitan cities of Kuala Lumpur (9.2%) and Singapore (22.1%).

    CONCLUSION: The ethnicity-specific prevalence rate of myopia was the lowest among Malays in Kota Bharu, followed by Kuala Lumpur, and is the highest among Singaporean Malays. Better socio-economic factors could have contributed to higher myopia rates in the cities, since the genetic background of these ethnic Malays are similar.

    Matched MeSH terms: Refractive Errors/complications; Refractive Errors/epidemiology*; Refractive Errors/physiopathology
  8. Hopkins S, Narayanasamy S, Vincent SJ, Sampson GP, Wood JM
    Clin Exp Optom, 2020 05;103(3):278-289.
    PMID: 31441091 DOI: 10.1111/cxo.12953
    The role of visual acuity and refractive errors in the academic performance of children is controversial due to the variable quality of the research in this area and the mixed findings reported. This review aims to provide clarity by reviewing and critiquing relevant peer-reviewed publications and also summarises what is known regarding the visual demands of modern classroom environments. The outcomes of this review suggest that while a number of studies have investigated the role of vision in relation to children's academic performances, the veracity of the evidence obtained from the majority of these studies is undermined by methodological limitations. Comparisons between studies are constrained by differences in experimental designs, instrumentation and sample characteristics. Despite these limitations, the weight of evidence suggests there is an association between academic performance and both visual acuity and refractive error in children. However, well-designed experimental studies are necessary to further understand the relationship between these parameters.
    Matched MeSH terms: Refractive Errors
  9. Mohd-Ali B, Mohammed Z, Norlaila M, Mohd-Fadzil N, Rohani CC, Mohidin N
    Clin Exp Optom, 2006 May;89(3):150-4.
    PMID: 16637969 DOI: 10.1111/j.1444-0938.2006.00033.x
    Down syndrome is a common chromosomal anomaly. Few reported studies make reference to the ocular status in Asian children with Down syndrome. The purpose of this study was to determine the visual and binocular status of a sample of Down syndrome children in Malaysia.
    Matched MeSH terms: Refractive Errors/complications; Refractive Errors/epidemiology; Refractive Errors/physiopathology
  10. Norhani Mohidin, Saadah Mohd Akhir, Bariah Mohd Ali, Zainora Mohammed, Sharanjeet, K., Chung, K.M.
    MyJurnal
    A vision screening study was carried out among Indian schoolchildren around Kuala Lumpur to determine whether the prevalence of myopia was higher in boys or girls. Altogether 749 students (49.7% boys and 50.3% girls) aged 7-18 years were screened and their refractive error examined using retinoscopy without cycloplegia. For the right eye 15.1% of the girls' eyes were found to be myopic as compared to 16.9% of the boys, of which chi-square showed no significant difference (p = 0.44). For the left eye 18.8% of the girls' eyes were myopic as compared to 16.4% of the boys. Chi square also showed no significant difference (p = 0.26). When high myopia (> -6.00D) was considered, there was no difference found between boys and girls. The number of students with high myopia greater than -6.00D was also very small (0.3%-0.5%). In conclusion, it was found that there was no significant difference in myopia between girls and boys among Indian schoolchildren.
    Matched MeSH terms: Refractive Errors
  11. Bariah Mohd-Ali, Ho, Oi Ching, NorAzizah Abd Latif
    MyJurnal
    The purpose of this study is to determine the standard value of corneal thickness (CCT) and its relationship with the degree of myopia amongst one sample of myopic students in Malaysia. Eighty-four myopic subjects (168 eyes) were examined in this study. Ocular examination included subjective refraction, keratometry (Shin-Nippon, Japan) and optical pachometry (Sonogage INC). Corneal thickness was measured at five different locations i.e. central, superior, inferior, nasal and temporal of the cornea. However, only association of CCT with myopia is reported in this article. Mean age of subjects was 21.42 ± 1.47 years old (20.34 ± 1.15; 22.46 ± 0.88). Mean refractive error in spherical equivalent for the whole sample was –3.50 ± 2.10 DS. Mean corneal curvature for the all subjects was 7.74 ± 0.52 mm and mean value of CCT was 594.62 ± 66.51 mm. Significant differences (p < 0.05) were found between mean CCT of low myopes (-4.00DS and below) and higher ones (-4.25DS and above), but not with mean of keratometer readings. Poor correlations were obtained between refractive error and CCT (r = 0.125, p > 0.05) and between refractive error and corneal curvature (r = 0.24, p > 0.05). It was concluded from this study that high myopic subjects has significantly thinner CCT than lower ones. Measurement of CCT should be considered when undertaking procedures such as LASIK and orthokeratology.
    Matched MeSH terms: Refractive Errors
  12. Kaur S, Waheeda Azwa, Norliza Mohd Fadzil, Azrin E. Ariffin
    Sains Malaysiana, 2011;40:1325-1329.
    This study was conducted to compare the treatment outcome using patching in patients with strabismic amblyopia and refractive amblyopia. The treatment outcome was measured by visual acuity and refractive error. A total of 28 patients participated in this study. One group comprised of strabismic amblyopes who had either congenital esotropia or intermittent exotropia and spherical equivalent refractive error of less than -3.00 DS. Another group of patients were purely refractive amblyopes. Patients were first corrected with the best correction for a month. When the VA in the amblyopic eye did not improve over the month, then patching treatment was started. Patching was done daily for 2 h together with near activity. The treatment was carried out for 4 months, with the patients reviewed once every month. The results of the study revealed that VA improved by 17 alphabets or 3 lines after patching treatment for patients with strabismic amblyopia. In the refractive amblyopia group, the VA only improved by 8 alphabets or 1 line 3 alphabets. The mean spherical equivalent refractive error changed by less than -0.50DS and therefore was clinically not significant in both groups. This present study showed that patching treatment was better at improving the VA of patients with strabismic amblyopia.
    Matched MeSH terms: Refractive Errors
  13. Elango S, Reddy TN, Shriwas SR
    Ann Trop Paediatr, 1994;14(2):149-52.
    PMID: 7521631
    The prevalence of ocular abnormalities was studied in 165 children from a Malaysian school for the deaf. Ninety-five children (57.6%) had one or more ocular abnormalities. Rubella retinopathy was the commonest form of ocular abnormality (35.2%). Refractive errors were found in 23 children (13.9%). Refractive errors in the rubella group were significantly more common than in the non-rubella group of deaf children (p < 0.001) (chi 2 test). Thirteen children had congenital anomalies causing significantly impaired vision. Ophthalmological examination of deaf children helps in the detection of cases with rubella eye signs and thus helps to identify the cause of deafness. Since deaf children are at greater risk of visual and ocular abnormalities, periodical ophthalmological examination should be carried out in these children.
    Matched MeSH terms: Refractive Errors/complications*; Refractive Errors/epidemiology
  14. Garner LF, Meng CK, Grosvenor TP, Mohidin N
    Ophthalmic Physiol Opt, 1990 Jul;10(3):234-8.
    PMID: 2216470
    A cross-sectional study of 753 Melanesian children in Vanuatu and 904 Malay children in Malaysia included measurement of refractive error and ocular dimensions. All children were between the ages of 6 and 17 years. The prevalence of myopia in Malay children was 4.3% at 7-8 years and 25.6% at 15-16 years with corresponding figures of 0.8% and 4.3% for Melanesian children. The range of refractive error was greater for Malay children at all ages. Mean refractive error for Malay children showed greater hypermetropia, together with a shorter axial length at 6 years, than Melanesian children, but at 17 years the situation reversed and Malay children had more myopia and longer axial lengths than their Melanesian counterparts.
    Matched MeSH terms: Refractive Errors/ethnology*; Refractive Errors/pathology
  15. Chen AH, Ahmad A, Kearney S, Strang N
    Graefes Arch Clin Exp Ophthalmol, 2019 Sep;257(9):1997-2004.
    PMID: 31273509 DOI: 10.1007/s00417-019-04405-z
    PURPOSE: Near work, accommodative inaccuracy and ambient lighting conditions have all been implicated in the development of myopia. However, differences in accommodative responses with age and refractive error under different visual conditions remain unclear. This study explores differences in accommodative ability and refractive error with exposure to differing ambient illumination and visual demands in Malay schoolchildren and adults.

    METHODS: Sixty young adults (21-25 years) and 60 schoolchildren (8-12 years) were recruited. Accommodative lag and accommodative fluctuations at far (6 m) and near (25 cm) were measured using the Grand Seiko WAM-5500 open-field autorefractor. The effects of mesopic room illumination on accommodation were also investigated.

    RESULTS: Repeated-measures ANOVA indicated that accommodative lag at far and near differed significantly between schoolchildren and young adults [F(1.219, 35.354) = 11.857, p  0.05). Accommodative lag and fluctuations were greater under mesopic room conditions for all ages [all p 

    Matched MeSH terms: Refractive Errors/epidemiology; Refractive Errors/physiopathology*
  16. Jusoh S, Shaharuddin B, Wan Hitam WH
    Clin Exp Ophthalmol, 2011 Jan;39(1):15-22.
    PMID: 20659136 DOI: 10.1111/j.1442-9071.2010.02385.x
    This study aims to assess the optic disc characteristics in healthy adult Malays and to correlate them with age, gender and refractive errors.
    Matched MeSH terms: Refractive Errors/diagnosis; Refractive Errors/ethnology
  17. Abolbashari F, Mohidin N, Ahmadi Hosseini SM, Mohd Ali B, Retnasabapathy S
    Cont Lens Anterior Eye, 2013 Aug;36(4):191-5.
    PMID: 23375190 DOI: 10.1016/j.clae.2013.01.005
    To assess changes in anterior segment parameters of keratoconus eyes at different stages of the disease in a sample of the Asian population.
    Matched MeSH terms: Refractive Errors/diagnosis*; Refractive Errors/epidemiology*
  18. Omar R, Wan Abdul WMH, Knight VF
    BMC Public Health, 2019 Jun 13;19(Suppl 4):543.
    PMID: 31196018 DOI: 10.1186/s12889-019-6865-3
    BACKGROUND: School children are considered a high-risk group for visual impairment because uncorrected refractive errors and problems such as amblyopia can seriously affect their learning abilities and their physical and mental development. There are many studies reporting the prevalence of refractive errors among school children of different ethnic groups in Malaysia, however, studies concerning the prevalence of refractive errors among indigenous or Orang Asli children are very limited. Therefore, the objective of this study was to determine the prevalence and causes of visual impairment among Orang Asli children.

    METHODS: One hundred ten Orang Asli children aged 7 to 12 years old in Negeri Sembilan, Malaysia were selected. 51% of these children were boys while the remainders were girls. They underwent visual acuity test, cover test, Hirschberg's test, ocular external assessment and ophthalmoscopy. Children who failed the vision screening were then referred for further eye examination.

    RESULTS: Of these 110 Orang Asli children, 46 failed the vision screening and subsequently 45 of them were confirmed to have visual problems (40.9% of the total subjects). The main cause of visual impairment in this study was refractive error (34.5% of the total subjects) where the main refractive error found was hyperopia (28.2%) followed by amblyopia (2.7%), strabismus (1.8%) and ocular abnormalities (1.8%).

    CONCLUSION: Hence, vision screening and a comprehensive eye examination is very important and needs to be done on all Orang Asli children so that any visual problems can be detect at an early stage to avoid the development of learning difficulties among these already disadvantaged children.

    Matched MeSH terms: Refractive Errors/ethnology; Refractive Errors/epidemiology*
  19. Saidatul Norbaya Buang, Abdul Shukor Salha, Marhaida Mahmood, Noor Haire Sumarlie Nordin
    MyJurnal
    Introduction: Refractive error is the most common cause of visual impairment among the school children. The visual acuity screening has long been administered through the school health service in Malaysia. The objective of this study was to examine the status of refractive error in the school health screening from year 1990 to 2017. Methods: Every year an average of 1.2 million students were screened for refractive errors through school health service. Stu-dents with visual acuity reading of 6/9 or worst based on 6-meter Snellen chart ware referred for confirmation of refractive error. Secondary data on school visual acuity screening from the Health Informatics for the period of 1990 to 2017 were used to describe the changing pattern of refractive errors. Results: It was observed that the prevalent of suspected refractive errors amongst the Standard 1 student increased from 7 per 1,000 students examined in 1990 to 44.4 per 1,000 students in the 2000 and further increased to 74 per 1,000 students before slow decline to 55 per 1,000 students from year 2015 to 2017. A higher level of detection was observed for students in standard 6 and form 3 between the period of 1990 to 2009 (78/1,000 and 65/1,000 respectively) and further decline thereafter to lowest level in 2017 (33/1,000 to 21.5/1,000 respectively). Conclusion: The Standard 1 students in the 21st century have higher rate of suspected refractive errors compared to their counterpart that lived in the 20th century. Community awareness program need to be introduce for early detection of visual acuity problem.
    Matched MeSH terms: Refractive Errors
  20. Bariah, M.A ., Leong, S.Y.
    MyJurnal
    Introduction: The corneal endothelium is made up of an extremely thin layer of non -regenerating cells essential in keeping the cornea clear. The purpose of this study was to quantify the corneal endothelial cells morphology, visual acuity (VA) and refractive error in patients having femtosecond laser-assisted cataract surgery (FLACS) and conventional phacoemulsification surgery (CPS). Methods: Clinical data from 56 eyes were included in this study. 28 eyes had FLACS surgery and another 28 eyes had CPS. Distance VA, refractive error, corneal thickness and endothelial cells morphology were evaluated pre-operatively and at 1 month follow up. Refractive error was determined subjectively and VA was taken using Snellen chart. Specular microscope was used to measure endothelial cells morphology and central corneal thickness. Mann Whitney test and Spearman correlation analysis were used to analyse the results. Results: There were no statistically significant difference in the mean endothelial cell density (p=0.24), mean central corneal thickness (p=0.68), mean coefficient of variance (p=0.19), mean hexagonality (p=0.44), VA (p=0.72) and postoperative refractive outcome (p=0.66) between both groups. The duration of surgery was noted to have no statistically significant difference between both groups (p=0.08), while the cumulative dissipated energy and torsional time showed a significant difference between groups (p=0.01 and p
    Matched MeSH terms: Refractive Errors
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