Displaying publications 21 - 40 of 102 in total

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  1. Mutilab HA, Sharanjeet-Kaur, Keu LK, Choo PF
    Clin Ter, 2012;163(3):199-204.
    PMID: 22964691
    PURPOSE: The objective of this study was to determine the visual function of colour-deficient subjects when wearing special red tint contact lenses.
    MATERIALS AND METHODS: A total of 17 subjects with congenital colour vision deficiency (14 deutans and 3 protans), voluntarily participated in this study. The average age for the subjects was 23.00 ± 4.06 years old. Visual functions tested were visual acuity (LogMAR), contrast sensitivity (FACT Chart) and stereopsis (TNO and Howard Dolman tests). Two types of special red tint lenses were used in this study; Type I (light red) and Type II (dark red).
    RESULTS: The protans and deutans showed no significant changes in visual acuity and contrast sensitivity when wearing either type of contact lens. Stereopsis testing using the Horward-Dolman test gave no significant changes but significant differences were seen using the TNO test. Stereopsis using the TNO test was significantly poorer with the red tinted contact lenses compared to without for both protons and deutans. Testing binocularly with Ishihara plates showed that 88% (n=15) of patients passed the test with Type I and Type II contact lenses. When D15 test was done, 3 patients (17.6%) were 'normal' when using the Type I contact lenses and 2 patients (11.8%) were 'normal' when using the Type II contact lenses. However, with FM100Hue test, most patients showed deutan responses. Total error scores (TES) were found to be higher with Type I and Type II contact lenses compared to without.
    CONCLUSIONS: The Type I and II special tinted contact lens used in this study did not cause a reduction of visual acuity and contrast sensitivity for the colour defects. Stereopsis was also not reduced with the Type I and Type II contact lenses for the colour defects except when tested with the TNO test. Colour vision defects became difficult to detect using the Ishihara plates but FM100Hue test did not show any improvement with the Type I and Type II contact lenses.
    Matched MeSH terms: Contact Lenses*
  2. Cheah PS, Norhani M, Bariah MA, Myint M, Lye MS, Azian AL
    Cornea, 2008 May;27(4):461-70.
    PMID: 18434851 DOI: 10.1097/ICO.0b013e318165642c
    To investigate the histological changes in primate cornea induced by short-term overnight orthokeratology (OK).
    Matched MeSH terms: Contact Lenses*
  3. Jaais F
    Med J Malaysia, 1998 Sep;53(3):272-6.
    PMID: 10968165
    Secondary intraocular lens implantation after cataract surgery done in University Hospital between 1983 to 1993 were reviewed. Thirty three patients (37 eyes) underwent secondary intraocular lens implantation during this period. Twenty four eyes had secondary anterior chamber lens implantation while 13 had posterior chamber lens implantation. There was no case of secondary posterior scleral fixation lens implantation. Visual acuity of 6/9 or better was seen in 25 of 37 eyes (67%) in the series. Eyes seeing as good or better than before secondary implantation procedure were noted in 34 of 37 eyes (92%). Vision of 6/9 or better was seen in 9 of 13 eyes (70%) with posterior chamber implants and 16 of 24 eyes in (67%) with anterior chamber lenses. Complications including bullous keratopathy, uveitis and glaucoma were seen with anterior chamber implants of the rigid type resulting in poorer visual acuity than before the secondary procedure.
    Matched MeSH terms: Lenses, Intraocular*
  4. Kamel AG, Norazah A
    Trans R Soc Trop Med Hyg, 1995 11 1;89(6):652.
    PMID: 8594684
    Matched MeSH terms: Contact Lenses/adverse effects*
  5. Bhandari M, Wei Ern RL, Majumder C, Ho D
    Med J Malaysia, 2019 02;74(1):30-33.
    PMID: 30846659
    PURPOSE: To determine the effects of ChromaGen blue filter lens in reading speed, accuracy and contrast sensitivity.

    METHODS: A cross-over, randomised study was carried out on 40 individuals (11 males and 29 females) aged 21 to 30 years. The rate of reading and reading accuracy was calculated with and without ChromaGen blue filter lens in all subjects. Wilkins Rate of Reading Test was used to measure the rate of reading and reading accuracy. Contrast sensitivity was also evaluated by using with and without the ChromaGen blue filter lens.

    RESULTS: The mean rate of reading with and without ChromaGen blue filter lens was 160.58±16.03 words per minute and 150.52±15.66 words per minute respectively, with significant difference of p<0.001. The mean of reading accuracy (words correctly read per minute) in subjects, with ChromaGen blue filter was 149.30±0.79 words and without using filter lens was 148.53±1.11 words and found to be significant (p<0.001). There was no significant difference in the contrast sensitivity between subjects with and without the ChromaGen blue filter lens (p=0.083). No significant correlation was noted between the reading speed with age, spherical equivalent, contrast sensitivity, and reading accuracy.

    CONCLUSION: This study concludes that there was an increase of 6.68% in the rate of reading and improvement of 0.52% in accuracy among subjects with ChromaGen blue filter lens.

    Matched MeSH terms: Contact Lenses*
  6. Mohidin N, Mat Yacob A, Norazman FN
    Med J Malaysia, 2020 09;75(5):538-542.
    PMID: 32918423
    BACKGROUND: Menicon Z night orthokeratology (OK) lenses was introduced in Malaysia in 2015 and to date there is no report on its effects on the cornea. The objective of this study was to examine short term changes in corneal thickness and morphology of endothelial cells in young Malay adults after wearing Menicon Z night OK lenses.

    METHODS: Corneal thickness was measured at the central and mid-peripheral locations of 20 participants aged 22.45±1.19 years using Tomey SP-3000 A-scan ultrasonography. Endothelial images of the central and peripheral locations captured using Tomey EM-3000 specular microscope were noted. Corneal thickness, endothelial cell density (ECD), coefficient of variation in cell size (CV), and hexagonality (HEX) at baseline, 24 hours, three months and six months after treatment were noted and analysed using repeated measure analysis of variance.

    RESULTS: Central corneal thickness decreased significantly over a three-month period (p=0.001) and stabilised thereafter. There were no significant changes in thickness in all peripheral areas measured (p>0.05), and in ECD, CV and HEX after the six-month period (p>0.05).

    CONCLUSIONS: The current study showed that significant thinning of central cornea and none at the mid-periphery. OK lens wear with Menicon Z night lenses had no effects on corneal morphology over the six month period.

    Matched MeSH terms: Lenses*
  7. Mohd-Ali B, Tan XL
    PMID: 31861174 DOI: 10.3390/ijerph16245161
    BACKGROUND: Contact lenses (CLs) are more popular than spectacles for vision correction amongst the youth. Knowledge about the risks of wearing CLs is critical especially for those with poor access to public health education. This study investigates the patterns of use and level of knowledge about CL wear amongst teenagers living in rural areas in Selangor, Malaysia using a set of validated questionnaires.

    METHODS: A total of 8500 self-administered questionnaires were distributed in eight selected secondary schools. The results were analysed using descriptive statistics.

    RESULTS: A total of 2474 (29%) completed questionnaires were collected. The mean age of the respondents was 14.8 ± 1.5 years, and approximately 7.2% were CL wearers. The majority of the wearers were females (76.0%) and wore soft CLs (92.2%). Cosmetic purposes (58.1%) and comfort (24.6%) were the main reasons for wearing CLs. Many of the respondents purchased their lenses from optical shops (50.1%) and beauty accessory shops (15.6%), and approximately 10% did not disinfect their lenses properly. Regarding knowledge about CL care, approximately 56% of the respondents responded correctly.

    CONCLUSION: Half of the respondents do not have sufficient knowledge about the risks of wearing CLs. Thus, aggressive public health education aimed at teenagers is needed to prevent improper CL usage.

    Matched MeSH terms: Contact Lenses*
  8. Tong WY, Tan WN, Kamarul Azizi MA, Leong CR, El Azab IH, Lim JW, et al.
    Chemosphere, 2023 Oct;338:139492.
    PMID: 37451643 DOI: 10.1016/j.chemosphere.2023.139492
    Vancomycin is the last resort antibiotic for the treatment of severe bacterial keratitis. Its clinical application is limited due to its hydrophilicity and high molecular weight. To overcome this, this study aims to develop nanoparticles-laden contact lens for controlled ocular delivery of vancomycin. Polyvinyl alcohol (PVA) was used as encapsulant material. The nanoparticles had a negative surface charge and an average size of 147.6 nm. A satisfactory encapsulation efficiency (61.24%) was obtained. The release profile was observed to be slow and sustained, with a release rate of 1.29 μL mg-1 h-1 for 48 h. Five out of 6 test bacteria were suppressed by vancomycin nanoparticles-laden contact lens. Vancomycin is generally ineffective against Gram-negative bacteria and unable to pass through the outer membrane barrier. In this study, vancomycin inhibited Proteus mirabilis and Pseudomonas aeruginosa. Nano-encapsulation enables vancomycin to penetrate the Gram-negative cell wall and further destroy the bacterial cells. On Hohenstein challenge test, all test bacteria exhibited significant reduction in growth when exposed to vancomycin nanoparticles-laden contact lens. This study created an effective and long-lasting vancomycin delivery system via silicone hydrogel contact lenses, by using PVA as encapsulant. The antibiotic efficacy and vancomycin release should be further studied using ocular in vivo models.
    Matched MeSH terms: Contact Lenses*
  9. Hamid SA, Rahman NHA, Yamada Y, Hung PV, Quoc DN
    Sensors (Basel), 2020 Oct 07;20(19).
    PMID: 33036419 DOI: 10.3390/s20195703
    Narrow beam width, higher gain and multibeam characteristics are demanded in 5G technology. Array antennas that are utilized in the existing mobile base stations have many drawbacks when operating at upper 5G frequency bands. For example, due to the high frequency operation, the antenna elements become smaller and thus, in order to provide higher gain, more antenna elements and arrays are required, which will cause the feeding network design to be more complex. The lens antenna is one of the potential candidates to replace the current structure in mobile base station. Therefore, a negative refractive index shaped lens is proposed to provide high gain and narrow beamwidth using energy conservation and Abbe's sine principle. The aim of this study is to investigate the multibeam characteristics of a negative refractive index shaped lens in mobile base station applications. In this paper, the feed positions for the multibeam are selected on the circle from the center of the lens and the accuracy of the feed position is validated through Electromagnetic (EM) simulation. Based on the analysis performed in this study, a negative refractive index shaped lens with a smaller radius and slender lens than the conventional lens is designed, with the additional capability of performing wide-angle beam scanning.
    Matched MeSH terms: Lenses
  10. Allinjawi K, Kaur S, Akhir SM, Mutalib HA
    Saudi J Ophthalmol, 2020 12 28;34(2):94-100.
    PMID: 33575529 DOI: 10.4103/1319-4534.305035
    PURPOSE: The purpose was to determine the minimum near-addition power needed using Proclear® multifocal D-Design contact lens (adds: +1.50 D, +2.50 D, +3.00 D, and +3.50 D) to invert the pattern of relative hyperopic defocus in the peripheral retina into relative myopic defocus among the eyes of myopic schoolchildren.

    METHODS: Twenty-seven right eyes (24 females and 3 males) of 27 myopic schoolchildren aged between 13 and 15 years were included in this study. The measurements of central refraction, peripheral refraction (between 35° temporal and 35° nasal visual field in 5° steps), and lag of accommodation were conducted using the Grand-Seiko WR-5100K open-field autorefractometer initially without correction (WC), followed by with correction using four different addition powers of Proclear® multifocal D-Design contact lens in random sequence. Axial length was measured using a handheld probe ultrasound A-scan (Tomey AL-2000).

    RESULTS: The relative peripheral refractive error showed high hyperopic defocus of +1.08 ± 1.24 D at 35° nasal and +1.06 ± 1.06 D at 35° temporal visual field WC. All Proclear multifocal contact lenses (MFCLs) decreased the peripheral hyperopic defocus with increasing addition powers (F [2.938, 47.001] = 13.317, P < 0.001). However, only +3.00 D addition and +3.50 D addition (P = 0.001) could invert the peripheral hyperopic defocus into peripheral myopic defocus. Apart from that, the +3.00 D addition lens showed the lowest lag of accommodation (+1.10 ± 0.83 D) among the other MFCL adds (P = 0.002).

    CONCLUSION: A +3.00 D addition Proclear MFCL is the optimal addition power that can invert the pattern of peripheral hyperopic defocus into myopic defocus.

    Matched MeSH terms: Contact Lenses
  11. Bariah Mohd Ali, Goh, E.H.
    MyJurnal
    The objective of this study was to determine the efficiency of UV blocking monomers in contact lenses in providing eye protection from UV radiation. The spectral transmission of 8 contact lenses (7 soft contact lenses: Precision UV, Acuvue 2, Surevue, Omega, Encore UV, Durasoft 3 and Lunelle UV and 1 rigid gas permeable contact lens: Boston 7) was evaluated by using a dual beam spectrophotometer. Durasoft 3, a non UV absorbent contact lens was used as the control. The results showed that Precision UV contact lens absorbed UV light up to wavelength of 380 nm, whereas Acuvue 2 and Surevue absorbed up to 360 nm only. Omega, Encore UV and Lunelle UV lenses absorbed UV light up to 335 nm with spectral transmission of Lunelle UV being the highest among all soft contact lenses tested, which was 17%. Boston 7 could absorb UV light up to 385 nm, but the amount of UV light transmitted was higher than soft lenses, which was 30%. Durasoft 3 only blocked UV light at 200-245 nm. Precision UV lens had better UV blocker characteristics than the other contact lenses tested. UV blocking soft contact lenses could be an alternative for spectacles in protecting internal ocular structures from UV radiation.
    Matched MeSH terms: Contact Lenses, Hydrophilic
  12. Norhani Mohidin, Yap MK, Jacobs RJ
    Sains Malaysiana, 2014;43:1089-1094.
    The purpose of this study was to compare the performance of four different electrode types in detecting the multifocal electroretinogram (mfERG) using the visual evoked response imaging system (VERIS). Multifocal ERG of 30 healthy subjects aged 17-50 years was recorded. Four different types of electrodes were used (JET contact lens, gold foil, DTL thread and c-glide carbon fiber electrodes) and the trough to peak amplitude response densities of the first order kernels (which approximated to the a and b wave of the full field electroretinogram) were compared. The JET contact lens electrode produced the highest amplitude response which was significantly different from the gold foil, DTL thread and the c-glide electrodes, but there was no significant difference between the gold foil and DTL or between DTL and the c-glide electrodes. In conclusion, contact lens electrode produced the highest response density followed by the gold foil and the DTL thread. There was no significant difference in amplitude response between the gold foil and DTL thread, therefore these two electrodes provide for viable alternatives for recording mfERG especially when there are concerns that contact lens electrode may be uncomfortable for recording periods that may take a long time.
    Matched MeSH terms: Contact Lenses
  13. Bastion ML
    BMJ Case Rep, 2010;2010.
    PMID: 22242074 DOI: 10.1136/bcr.10.2009.2398
    The use of 0.5 mg/0.05 ml of ranibizumab intracamerally, to induce regression of iris neovascularisation in a non-diabetic patient, is reported. A 55-year-old Malay man presented with left eye rubeosis and hyphaema secondary to ischaemic remnant retinal flap in his silicone filled pseudophakic eye. Regression of rubeosis and resolution of hyphaema was noted within 4 days of injection of intracameral ranibizumab, allowing repeat vitrectomy to be performed without much bleeding, thus facilitating removal of his intraocular lens and laser to remaining flap. One month postoperatively he remained comfortable with counting fingers vision similar to the pre-hyphaema period.
    Matched MeSH terms: Lenses, Intraocular
  14. Kuan BB, Lim TK
    Med J Malaysia, 1984 Dec;39(4):280-4.
    PMID: 6544933
    Ultrasound measurement of ocular dimension is the chosen method for assessing axial length when determining dioptric power for intraocular lens. From the current results of 30 cases studied, the mean axial length ranges from 22 to 23 mm. Despite the limitation of the accuracy of the ultrasonic measurements with the 7.5 mHz transducer, the power of intraocular lens can. be determined satisfactorily in accordance with the knowledge of keratometric reading. Hence, high refractive errors could be avoided post-operatively.
    Matched MeSH terms: Lenses, Intraocular
  15. Lili Asma Ismail, Lekhraj Rampal, Hejar Abdul Rahman, Nazri Omar, Habshah Midi, Azrin Esmady Ariffin
    MyJurnal
    Microbial keratitis is one of the most challenging complications of contact lens (CL) wear. Proper CL practice plays an important role to reduce the risk for contact lens related microbial keratitis (CLRMK). Methods: This multi-centre case-control study was conducted from January 2008 until June 2009 to determine the risk factors associated with CLRMK. Cases were defined as respondents who were treated for CLRMK, whilst controls were respondents who were contact lens wearers without microbial keratitis. Ninety four cases were compared to 94 controls to determine the risk factors for
    CLRMK. Results: The predictors for CLRMK were: Not washing hands with soap before handling CL (aOR 2.979, CI 1.020, 8.701 p=0.046), not performing rubbing technique whilst cleaning the CL (aOR 3.006, CI 1.198, 7.538 p=0.019) and, not cleaning the lens case with multipurpose solution daily (aOR 3.242 CI 1.463, 7.186 p=0.004). Sleeping overnight with the CL in the eye (aOR 2.864, CI 0.978, 8.386 p=0.049) and overall non-compliance with lens care procedures (aOR 2.590, CI 1.003, 6.689 p=0.049) contributed significantly to CLRMK. Conclusion: Health education and promotion in contact lens care are important and should be conducted by eye care practitioners to reduce the occurrence of CLRMK.
    Matched MeSH terms: Contact Lenses
  16. Noradilah Samseh Abdullah, Mohamed Kamel Abd Ghani, Anisah Nordin, Yusof Suboh, Noraina Ab Rahim
    MyJurnal
    Acanthamoeba keratitis is a serious ocular problem and can cause blindness if not treated. This study was therefore performed to evaluate the effectiveness of eyedrop antibiotics on eight Acanthamoeba spp. isolates, of which four
    were clinical isolates and the remaining four from the environment. Three different eyedrop antibiotics (neomycin, ciprofloxacin and gentamicin) currently available in the market and ready for use were tested. Cyst suspension from all strains were tested against eyedrop antibiotics, respectively. After 48 hours of incubation period, the solutions were filtered and the filtered membranes were put onto non-nutrient agar lawn with E. coli. The plates were examined daily for Acanthamoeba trophozoites under inverted microscope until day 14. Neomycin, ciprofloxacin and gentamicin were found
    to be effective against Acanthamoeba spp. cysts for all test strains.
    Key words: Acanthamoeba Keratitis, Eyedrop Antibiotics, Effectiveness
    Matched MeSH terms: Contact Lenses
  17. Syazwan Hafiz Mohd, Wan Elhami Wan Omar, Ai-Hong Chen
    MyJurnal
    This paper examines the chemical elements used as colour additives in cosmetic coloured contact lenses (Cos-CCL) using Field Emission Scanning Electron Microscope equipped with Energy Dispersive X-ray Spectroscopy (FESEM-EDX) analysis. The samples comprised two different Cos-CCL brands and colours (sample A1-black iris colour & B1-gray iris colour) with their respective clear contact lens counterparts as controls (sample A2 & B2). The parameters of Cos-CCL were observed carefully so that they resembled their respective controls. All the samples were analysed for chemical element characterisation by using EDX spectroscopy surface mapping analysis on both front and back surfaces. EDX spectroscopy point analysis was done on cross-section surface of Cos-CCL when colour additive pattern could not be detected by FESEM on either surface. FESEM-EDX spectroscopy analysis has revealed iron element in the colour additives of the A1 sample and aluminium elements in the B2 sample. These two elements were not present in the respective control samples. It can be concluded that iron and aluminium elements are exclusively attributed to the colour additive in Cos-CCL samples. It is important for manufacturers of Cos-CCL to disclose information of their products and create greater awareness on the risks facing users.
    Matched MeSH terms: Contact Lenses
  18. Vijayasingham L, Jogulu U, Allotey P
    Soc Sci Med, 2020 01;245:112699.
    PMID: 31785425 DOI: 10.1016/j.socscimed.2019.112699
    Reports of work change and transitions are common amongst individuals with chronic illnesses such as multiple sclerosis (MS). However, there is little research on the lived experience of these work transitions. The scarcity of this research is particularly evident within low-and-middle-income countries, where protection laws and resources such as anti-discrimination laws and reasonable work modifications may not exist or be well enforced. In this paper, we explore how and why individuals with MS seek and achieve work transitions in the structural context of Malaysia. We interviewed ten working individuals with MS (July-december 2015) using a joint hermeneutic phenomenology and constructivist grounded theory approach. Using a broad conceptual lens of 'sustainable careers', we examine their careers as a series of experiences, decisions, and events, paying attention to the influences of context, time, their personal levels of agency and sense of meaning. Participants described work transitions as early as within the first year of diagnosis, that were prompted by voluntary, involuntary and semi-voluntary reasons. Key aspects of the process of seeking new roles included an exploration of alternative roles and paths, and then acquiring, trialing/adapting and remaining engaged in their new roles. Participants identified the perception and experience of 'being unemployable', based on how their diagnosis and short-term symptoms were responded to by employers. Nevertheless, participants used various strategies and career resources to obtain and maintain meaningful work roles. However, success in obtaining or maintaining new roles were not equally achieved. This research draws attention to the cumulative economic disadvantage of a chronic illness diagnosis, even at milder and episodic stages. Furthermore, it reiterates the need for cohesive structural protection in low-and-middle-income countries to facilitate a more equal ability to remain economically resilient and capable of engaging in meaningful long-term careers when living with a chronic illness.
    Matched MeSH terms: Lenses
  19. Khor Wei Chung, Chow Weng Sum, Abd. Hadi A. Rahman
    Sains Malaysiana, 2015;44:931-940.
    The Sandakan Formation of the Segama Group is exposed across the Sandakan Peninsular in eastern Sabah. This Upper Miocene part of the Segama Group unconformably overlies the Garinono Formation and is conformably overlain by the Bongaya Formation. This formation was investigated with detailed logging of outcrops and microfossils analysis in order to map the depositional facies and sedimentary environment. This study showed the presence of seven lithofacies: Thick amalgamated sandstone; thin, lenticular interbedded HCS sandstones and mudstone; laminated mudstone with Rhizophora; trough cross-bedded sandstone; laminated mudstone; strip mudstone with thin sandstone and siltstone; and interbedded HCS sandstone and mudstone. Based on the presence of Rhizophora, Brownlowia, Florchuetia sp., Polypodium, Stenochleana palustris, Ascidian spicule low angle cross bedding, very fine grained sandstone, thin alternations of very fine sandstone, silt and clay layers showing cyclicity (muddy rhythemites), rocks in the Sandakan Formation are interpreted as mangal estuary and open marine facies. Three facies associations could be deduced from the seven lithofacies: Gradual coarsening upwards shoreface; abrupt change facies and prograding estuary facies association.
    Matched MeSH terms: Lenses
  20. Naicker P, Sundralingam S, Peyman M, Juana A, Mohamad NF, Win MM, et al.
    Int Ophthalmol, 2015 Aug;35(4):459-66.
    PMID: 25024102 DOI: 10.1007/s10792-014-9970-4
    To determine the accuracy of intraocular lens (IOL) calculations in eyes undergoing phacoemulsification cataract surgery with IOL implantation using immersion A-scan ultrasound (US) and Lenstar LS 900(®) biometry. In this prospective study, 200 eyes of 200 patients were randomized to undergo either Lenstar LS 900(®) or immersion A-scan US biometry to determine the IOL dioptric power prior to phacoemulsification cataract surgery. Post-operative refractive outcomes of these two groups of patients were compared. The result showed no significant difference between the target spherical equivalent (SE) and the post-operative SE value by the Lenstar LS 900(®) (p value = 0.632) or immersion A-scan US biometry (p value = 0.438) devices. The magnitude of difference between the two biometric devices were not significantly different (p value = 0.868). There was no significant difference in the predicted post-operative refractive outcome between immersion A-scan US biometry and Lenstar LS 900(®). Based on the results, the immersion A-scan US technique is as accurate as Lenstar LS 900(®) in the hands of an experienced operator.
    Matched MeSH terms: Lenses, Intraocular*
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