It is possible that different techniques used to measure axial length (AL) and anterior chamber depth (ACD) is the cause of discrepancy in refractive outcomes of cataract surgery. This study evaluated the agreement and repeatability of AL and ACD measurements using immersion and contact A-scan biometry techniques and compared the refractive outcomes from both techniques. Twenty four patients were evaluated for agreement and repeatability of AL and ACD measurements using the two different methods. The results were analyzed using Bland and Altman plots. Another 60 patients with age-related cataract were selected to compare the refractive outcomes between both methods. The IOL power was calculated using Sanders- Retzlaff- Kraff- Theoretical (SRK-T) equation. Refraction was determined between four to six weeks postoperatively and the results were analyzed using paired t-test. The results of this study showed good agreement between both techniques was noted with no significant difference detected between measurements (p > 0.05). Significant correlation was found in all parameters (AL: r = 0.99; p < 0.01, r = 0.99; p < 0.01) ACD: r = 0.91; p < 0.01, r = 0.97; p < 0.01). No significant difference in refractive outcomes of post cataract surgery was detected between the two techniques (p = 0.07). This study concludes that contact A-scan biometry and immersion techniques provide reliable results and should not be the cause of discrepancy in the refractive planned and outcome of cataract surgery.
Ujian teks bacaan Bahasa Melayu telah dibangunkan untuk menilai prestasi membaca kanak-kanak sekolah rendah.
Seramai 120 pelajar Tahap 1 (purata umur 8.5 ± 0.5 tahun) dan Tahap 2 (purata umur 10.5 ± 0.5 tahun) berpenglihatan
normal telah dipilih secara rawak. Subjek diminta membaca lima teks bacaan secara rawak dengan kuat. Masa selesai
membaca setiap teks bacaan diukur dan sebarang kesalahan menyebut perkataan direkodkan. Purata kelajuan membaca
dan kadar membaca diukur sebagai perkataan per minit (ppm). Kelajuan membaca Tahap 1 adalah 88.81 ± 1.95 {ralat
piawai (RP)} ppm dan kadar membaca pula adalah 87.20 ± 1.98 (RP) ppm. Bagi Tahap 2, kelajuan membaca adalah
108.12 ± 1.66 (RP) ppm manakala kadar membaca adalah 107.22 ± 1.67 (RP) ppm. Kelajuan dan kadar membaca di
antara subjek bagi setiap teks bacaan menunjukkan tiada perbezaan yang signifi kan (p > 0.05) dengan nilai p bagi
kedua-duanya adalah 0.91 manakala bagi tahap 2 pula nilai p adalah 0.57. Perbandingan di antara teks bacaan juga
menunjukkan tiada perbezaan yang signifi kan (p > 0.05). Semua teks bacaan adalah homogen secara statistik maka teks
bacaan yang dibangunkan boleh dipilih secara rawak semasa ujian dan tidak akan memberi kesan kepada penilaian
prestasi membaca di kalangan kanak-kanak sekolah rendah.
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.
Low vision device (LVD) is prescribed to visually impaired (VI) schoolchildren to assist in their learning. One of the factors
that could influence the success of LVD use is the skills of using the devices. The objective of this study is to compare the
reading speed of VI schoolchildren before and after receiving LVD training by special school teachers. Twenty-two special
school teachers attended a series of workshop on the use of LVD. Twenty-two VI schoolchildren were recruited and paired
with teachers for training of LVD in the classroom (in-classroom training). A suitable LVD was prescribed by the researcher
to the schoolchildren before training commence. The total in-classroom training was 5 hours which is 1 hour/week. In
classroom training was based on a module that was developed at the beginning of the study and the teachers used a
checklist to monitor the schoolchildren’s progress. Reading speed in words per minute (wpm) was measured using UKM
near chart before and after completion of in-classroom training. All teachers successfully completed the in-classroom
training session. Results from One-way repeated measure ANOVA test showed reading speed improved significantly after
5 hours of in-classroom training, F(1.6,34.4)= 35.53, p < 0.001, partial ŋ² = 0.63. Reading speed of VI schoolchildren
have improved after completion of in-classroom training. This suggests that systematic training of LVD given by the special
school teachers assist VI schoolchildren to use their device effectively and thus, improved their reading speed.
The purpose of this study is to determine the visual status and effectiveness of low vision devices among visually impaired school children. One hundred and thirteen students from the special education schools took part in this study. Distance and near visual acuity were measured both with and without low vision devices. Students needing further assessment were referred to the Low Vision Clinic (LVC) Universiti Kebangsaan Malaysia. On presentation, 31% of the students were catagorised as low vision with distance acuity between 6/18 and 6/95 whereas 67% were blind. 2% were found to have distance acuity better than 6/18. The range of near visual acuity of these students was between N4 and N64. Low vision devices such as hand held magnifier, stand magnifier and telescope, were owned by only 17% of low vision students. This study showed that 85% of the students that were referred to the LVC benefited from low vision devices. Access to visual examinations and eye care for students with needs to be provided so that these students can be identified early and suitable low vision devices prescribed. This study emphasises the importance of the role played by parents, teachers and optometrists in the management of vision impairment in school children so that their visual impairment can be rehabilitated effectively.
Keywords: Low vision assessment; low vision devices
The purpose of this study was to examine the effects of mild cognitive impairment on pattern electroretinogram (pERG)
among urban elderly Malays. A total of 36 subjects aged 60 years and above comprising of 18 MCI subjects and 18
normal controls were recruited for this study. The inclusion criteria for both the MCI and normal subjects included best
corrected distance visual acuity ≥ 6/9 (Snellen) with refractive error less than ±4.00 DS and/or ±2.00 DC (astigmatism),
near visual acuity ≥ N8, absence or no previous history of any significant media opacities, retinal disorders and ocular
pathologies. pERG was recorded with the RetiPort/Scan21 system in accordance with the International Society for the
Clinical Electrophysiology of Vision standards. The target presented to subjects through a 19” CRT monitor was a black
and white reversing checkerboard with luminance equal to 80 cd/m2
, contrast 97% and stimulus frequency 2.00 Hz (4
rev/s). Amplitudes and implicit times of P50 and N95 waves generated by the system were noted and compared between
the two groups. The results showed no significant difference in the amplitude and implicit times between the right and left
eyes so only the right eye was used for comparison between the MCI and control groups. The mean amplitude and implicit
times of the right eye of the MCI and control groups were 1.86±0.65 μV, 56.27±6.20 ms and 1.54±0.74 μV, 56.15±4.98 ms,
respectively. T-test showed no significant differences in pERG amplitudes and implicit times between MCI and the control
groups. In conclusion, our results may imply that the inner retina is intact in early MCI elderly subjects.
The first aim of this study was to determine the refractive error and visual acuity of Chinese elderly age 60 and above in Selangor and Johor, Malaysia. The second aim was to determine the percentage of elderly with vision impairment. Participants of this study were from the on-going population-based longitudinal study on neuroprotective model for healthy longevity (TUA) among Malaysian older adults using multistage random sampling. A total of 259 Chinese elderly aged 60 and above from state of Selangor and Johor agreed to participate. Refractive error was determined using autorefractometer Retinomax K-plus followed by subjective refraction. Best corrected visual acuity (VA) was measured using logMAR chart. Analysis was performed on data of 202 participants and the remaining 57 were excluded. Overall percentage of refractive error was higher for hyperopia (54%) compared to myopia (23.2%). High percentage of astigmatism was noted for all age groups (> 50%). Both gender showed similar distribution of refractive status. Mean overall VA was 0.24 ± 0.17 logMAR (≅ 6/9-) and mean VA declined with age. Overall, the percentage of elderly having at least mild vision impairment (> 0.3 logMAR or 6/12) was higher (62.9%) compared to normal vision (≤ 0.3 logMAR). However, percentage of vision impairment (VI) was highest in the mild category compared to others and only one participant had severe VI. This study found a high percentage of Chinese elderly with refractive error. The most common type of refractive error was hyperopia. A high proportion of them had mild vision impairment followed by moderate VI even with best correction. Vision impairment could affect daily life functioning and this effect can be further explored in the future.
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.
Kajian terdahulu banyak menunjukkan perbezaan dalam dimensi okular mengikut kaum. Walau bagaimanapun hanya terdapat sedikit data mengenai dimensi okular bangsa Melayu di Malaysia yang dilaporkan. Kajian ini bertujuan untuk menetapkan nilai normal dimensi okular bangsa Melayu muda di Malaysia. Seramai 584 orang telah diundang untuk menjadi subjek untuk kajian secara sukarela. Pengukuran yang dilakukan meliputi kelengkungan dan ketebalan tengah kornea, nilai esentrisiti kornea (e), diameter iris horizontal dan vertikal yang kelihatan, saiz pupil dan bukaan palpebral. Subjek dibahagikan kepada 3 kumpulan berikut mengikut umur dan dipadankan mengikut jantina dan umur: Kumpulan 1 (7-12 tahun, n = 188), Kumpulan 2 (13 to 18 tahun, n = 196) and Kumpulan 3 (19 to 24 tahun, n = 200). Pengukuran dilakukan menggunakan topografer kornea (CTK 922 dari Haag Streit, Jerman), pakometer ultrasonik (Corneo-Gage Plus 2 dari Sonogage Incorporated) dan auto refraktometer (Auto-Ref R1 dari Canon, Jepun). Dimensi okular bangsa Melayu yang diukur didapati lebih kecil dari bangsa lain di seluruh dunia. Perbezaan yang signifikan juga didapati untuk semua pengukuran dengan peningkatan umur (p < 0.05). Keputusan kajian ini boleh dijadikan rujukan untuk nilai dimensi okular populasi Melayu muda Malaysia di masa hadapan.
The aim of this study was to determine whether pattern-reversal Visual Evoked Potential (PRVEP) is affected in mild
cognitive impairment (MCI). Participants aged ≥ 60 years diagnosed as MCI were invited to participate in a study together
with a group of controls. PRVEP was measured using A RETI-port/Scan 21 and stimuli of large and small checks sizes,
1° (60 min of arc) and 0.25° (15 min) respectively were used to obtain responses. The amplitude and implicit times of
the MCI and control groups were then compared. A total of 18 MCI participants (age 65.7 ± 3.1 years) and 18 controls
(65.1 ± 3.8 years) consented to participate in the study. The amplitude and implicit times for the MCI group using the
target sizes of 60 min of arc were 9.80 ± 4.06 µV and 108.83 ± 7.63 ms and for 30 min of arc were 11.00 ± 7.44 µV
and 123.96 ± 6.18 ms respectively. Consecutively for the control groups the amplitudes and implicit times were 8.96 ±
3.52µV, 105.85 ± 3.60 ms and 11.97± 6.11 µV, 122.57 ± 8.28 ms. PRVEP results did not reveal significant differences in
P100-wave amplitude nor implicit time between the two groups under investigation. This study concluded that the visual
pathway of MCI participants may be unaffected in the early part of the disease process.
This study was conducted to determine the score of self-reported visual function index (VF-14) and its correlation with
best corrected visual acuity (BCVA) in the elderly population. Participants were elderly aged 60 years and above recruited
from the on-going population-based longitudinal study on neuroprotective model for healthy longevity (TUA). Visual
acuity was measured using logMAR chart. A self-reported visual function assessment was measured using modified
Bahasa Malaysia Visual Functioning Index (VF-14). A total of 482 (93.05%) from 518 subjects participated in this study.
Mean age was 69.18 ± 5.67 years old and mean best corrected VA was 0.21 ± 0.17 logMAR. Mean VF-14 score was 89.65
± 13.19. Female had lower mean score of self-reported visual function scores compared to male (meanfemale89.21 ± 12.76,
meanmale90.11 ± 13.65) but it was not statistically significant (z = -1.09,p = 0.277). There was a moderate but significant
correlation between VF-14 score and best corrected VA (r = -0.412, p < 0.01). In conclusion, the best corrected visual
acuity alone was not able to become as an indicator to describe changes in VF14 score. This study showed that it only
contributes 17.2% to changes in VF14 score. The combination of many other factors such as socio-demographic factors
(race, educational status, and health problems), contrast sensitivity and stereopsis should be taken into account when
assessing visual function as measured by VF14.
Eye movement is one of the most important mechanisms that function to collect the information from the environment to stimulate the motor action and thus enable a person to perform daily activities. The purpose of this study was to investigate whether eye movement parameters when performing activities of daily living (ADL) is affected by learning effect when the ADL were repeated. Thirteen school children aged between 15 and 19 years old (mean 16.31±1.89 years) participated in this study. They undergone two evaluations, baseline and follow up, separated by at least 10 weeks. The evaluation included assessment of visual acuity at near and distance using Lighthouse reduced ETDRS chart and Early Treatment Diabetic Retinopathy (ETDRS) chart, respectively; eye movement parameters (task duration, saccade latency and number of saccades) while performing ADL (identifying colours, coins and food) were recorded using Positive Science Portable LLC eye tracker. The mean value for the visual acuity at distance and near for baseline and follow up were logMAR -0.05±0.05 and logMAR -0.05±0.05, respectively. The results showed that comparison of eye movement parameters for performance of ADL at baseline and follow up were not statistically significant. Therefore, the findings of this study suggested that learning effect is not a factor that will influence change in eye movement parameters when performing ADL. These findings implied some benefit in using eye movement parameters for example to evaluate performance of ADL when given intervention in persons with nystagmus.
Illumination is one of the important physical aspects that influences comfortability during learning session particularly
among visually impaired students. The purpose of this study was to determine changes in illumination level in classrooms
during learning session at Sekolah Menengah Pendidikan Khas (SMPK), Setapak. The second objective was to compare
the illumination level in the classrooms under three different lighting conditions: daylight only, with additional artificial
light and with removal of obstructions to daylight. Illumination levels in 17 classrooms was measured at one hour interval,
between 8 am to 1 pm for the first stage and 19 classrooms under three different lighting conditions from 11 am to 12 noon
for the second stage, using ILM1335 (ISO-TECH, Taiwan) digital luxmeter. Illumination level increased significantly from
8 am to 11 am (One-Way Repeated Measures ANOVA: F(2.14, 34.26)=76.49, p<0 .001) and was maximum at 1 pm. The
illumination level was highest for the condition of daylight with additional artificial light (One-Way Repeated Measures
ANOVA: F(2,34)=110.51, p<0.001) compared to other conditions. Illumination levels for daylight without obstruction
was significantly higher than daylight only (pairwise comparison: p=0.001). Classroom illumination level was lowest
in the early morning. However, classroom illumination can be increased either by removing the obstructions to daylight
or with additional artificial lighting.