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Fulltext Branch retinal vein occlusion associated with quetiapine fumarate

Yong KC, Kah TA, Ghee YT, Siang LC, Bastion ML

BMC Ophthalmol, 2011;11:24.
PMID: 21867521 DOI: 10.1186/1471-2415-11-24

To report a case of branch retinal vein occlusion in a young adult with bipolar mood disorder treated with quetiapine fumarate.

Matched MeSH terms: Retina/pathology*
Baseline retinal nerve fiber layer thickness as a predictor of multiple sclerosis progression: New insights from the FREEDOMS II study

Wang L, Tan H, Yu J, ZhangBao J, Huang W, Chang X, et al.

Eur J Neurol, 2023 Feb;30(2):443-452.
PMID: 36286605 DOI: 10.1111/ene.15612

BACKGROUND AND PURPOSE: The aim was to evaluate the potential of retinal nerve fiber layer thickness (RNFLT) measured with optical coherence tomography in predicting disease progression in relapsing-remitting multiple sclerosis (RRMS).
METHODS: Analyses were conducted post hoc of this 24-month, phase III, double-blind study, in which RRMS patients were randomized (1:1:1) to once daily oral fingolimod 0.5 mg, 1.25 mg or placebo. The key outcomes were the association between baseline RNFLT and baseline clinical characteristics and clinical/imaging outcomes up to 24 months. Change of RNFLT with fingolimod versus placebo within 24 months and time to retinal nerve fiber layer (RNFL) thinning were evaluated.
RESULTS: Altogether 885 patients were included. At baseline, lower RNFLT was correlated with higher Expanded Disability Status Scale score (r = -1.085, p = 0.018), lower brain volume (r = 0.025, p = 0.006) and deep gray matter volume (r = 0.731, p

Matched MeSH terms: Retina/pathology
Fulltext Images in clinical medicine. Retinal detachment in malignant hypertension

Tajunisah I, Patel DK

N Engl J Med, 2009 Aug 27;361(9):899.
PMID: 19710488 DOI: 10.1056/NEJMicm0802683
Matched MeSH terms: Retina/pathology*
Bilateral Norrie's disease in identical twins

Sukumaran K

Br J Ophthalmol, 1991 Mar;75(3):179-80.
PMID: 2012789

A case of Norrie's disease in an identical twins is reported. No positive family history was obtained. The couple had no other children. The older of the twins died at the age of 9 months of uncertain cause. To the best of my knowledge this is the first case of Norrie's disease reported in Malaysia. And its occurrence in an identical twins is very rare.

Matched MeSH terms: Retina/pathology
Retinal vascular fractal and blood pressure in a multiethnic population

Sng CC, Wong WL, Cheung CY, Lee J, Tai ES, Wong TY

J Hypertens, 2013 Oct;31(10):2036-42.
PMID: 23787404 DOI: 10.1097/HJH.0b013e328362c201

OBJECTIVE(S): To examine the effect of blood pressure (BP) on retinal vascular fractal dimension (Df), a measure of microvascular network complexity and density in a multiethnic cohort.
METHODS: A population-based study of 3876 Chinese, Malay and Indian participants in Singapore. Retinal Df was measured using a computer-based program from digital retinal photographs. Associations between retinal Df and mean arterial BP (MABP) in the whole cohort and in each racial group were analysed using linear regression analysis. Logistic regression was used to examine the association between retinal Df and hypertension status.
RESULTS: The mean retinal Df of the study population was 1.45 (standard deviation 0.03). After adjustment for age, sex, race, diabetes, BMI, cholesterol and creatinine levels, persons with smaller Df had higher MABP (mean difference MABP was 6.18 mmHg comparing lowest to highest Df quartiles, P<0.001). This was similar in Chinese, Malay and Indian persons [mean difference 6.40 (P<0.001), 4.72 (P=0.011) and 6.62 (P<0.001)mmHg, respectively]. Persons with smaller retinal Df were more likely to have uncontrolled treated or untreated hypertension [odds ratio 1.79 (P=0.003) and 2.60 (P=0.003), respectively, comparing lowest to highest Df quartiles] than those with no hypertension; this relationship was not seen comparing persons with controlled treated hypertension with no hypertension (odds ratio 1.01, P=0.972).
CONCLUSION: Hypertension was associated with a sparser retinal vascular network, which was similar across different racial/ethnic groups and most apparent in those with uncontrolled or untreated hypertension. These data suggest that microvascular remodelling can be quantified by measuring retinal vasculature.

Matched MeSH terms: Retina/pathology
Advanced retinoblastoma in Malaysian children

Sinniah D, Narasimha G, Prathap K

Acta Ophthalmol, 1980 Oct;58(5):819-24.
PMID: 7211270

Twenty children with retinoblastoma are reviewed who were treated at the University Hospital, Kuala Lumpur over a 10-year-period. They constitute 6.6% of childhood malignancies and without exception all presented with advanced disease. Hereditary cases were notably absent in the the series probably because past cases have almost invariably succumbed without an opportunity to transmit the gene. With enucleation and radiotherapy six of the patients have survived from 2 to 12 years. The addition of vincristine and cyclophosphamide has not been associated with improved survival.

Matched MeSH terms: Retina/pathology
Fulltext Differential expression and role of hyperglycemia induced oxidative stress in epigenetic regulation of β1, β2 and β3-adrenergic receptors in retinal endothelial cells

Safi SZ, Qvist R, Yan GO, Ismail IS

BMC Med Genomics, 2014;7:29.
PMID: 24885710 DOI: 10.1186/1755-8794-7-29

Aberrant epigenetic profiles are concomitant with a spectrum of developmental defects and diseases. Role of methylation is an increasingly accepted factor in the pathophysiology of diabetes and its associated complications. This study aims to examine the correlation between oxidative stress and methylation of β1, β2 and β3-adrenergic receptors and to analyze the differential variability in the expression of these genes under hyperglycemic conditions.

Matched MeSH terms: Retina/pathology*
Fulltext Protective Effect of Palm Oil-Derived Tocotrienol-Rich Fraction Against Retinal Neurodegenerative Changes in Rats with Streptozotocin-Induced Diabetic Retinopathy

Sadikan MZ, Nasir NAA, Agarwal R, Ismail NM

Biomolecules, 2020 04 05;10(4).
PMID: 32260544 DOI: 10.3390/biom10040556

: Oxidative stress plays an important role in retinal neurodegeneration and angiogenesis associated with diabetes. In this study, we investigated the effect of the tocotrienol-rich fraction (TRF), a potent antioxidant, against diabetes-induced changes in retinal layer thickness (RLT), retinal cell count (RCC), retinal cell apoptosis, and retinal expression of vascular endothelial growth factor (VEGF) in rats. Additionally, the efficacy of TRF after administration by two different routes was compared. The diabetes was induced in Sprague-Dawley rats by intraperitoneal injection of streptozotocin. Subsequently, diabetic rats received either oral or topical treatment with vehicle or TRF. Additionally, a group of non-diabetic rats was included with either oral or topical treatment with a vehicle. After 12 weeks of the treatment period, rats were euthanized, and retinas were collected for measurement of RLT, RCC, retinal cell apoptosis, and VEGF expression. RLT and RCC in the ganglion cell layer were reduced in all diabetic groups compared to control groups (p < 0.01). However, at the end of the experimental period, oral TRF-treated rats showed a significantly greater RLT compared to topical TRF-treated rats. A similar observation was made for retinal cell apoptosis and VEGF expression. In conclusion, oral TRF supplementation protects against retinal degenerative changes and an increase in VEGF expression in rats with streptozotocin-induced diabetic retinopathy. Similar effects were not observed after topical administration of TRF.

Matched MeSH terms: Retina/pathology*
Fulltext Diabetic retinopathy: a comprehensive update on in vivo, in vitro and ex vivo experimental models

Sadikan MZ, Abdul Nasir NA, Lambuk L, Mohamud R, Reshidan NH, Low E, et al.

BMC Ophthalmol, 2023 Oct 19;23(1):421.
PMID: 37858128 DOI: 10.1186/s12886-023-03155-1

Diabetic retinopathy (DR), one of the leading causes of visual impairment and blindness worldwide, is one of the major microvascular complications in diabetes mellitus (DM). Globally, DR prevalence among DM patients is 25%, and 6% have vision-threatening problems among them. With the higher incidence of DM globally, more DR cases are expected to be seen in the future. In order to comprehend the pathophysiological mechanism of DR in humans and discover potential novel substances for the treatment of DR, investigations are typically conducted using various experimental models. Among the experimental models, in vivo models have contributed significantly to understanding DR pathogenesis. There are several types of in vivo models for DR research, which include chemical-induced, surgical-induced, diet-induced, and genetic models. Similarly, for the in vitro models, there are several cell types that are utilised in DR research, such as retinal endothelial cells, Müller cells, and glial cells. With the advancement of DR research, it is essential to have a comprehensive update on the various experimental models utilised to mimic DR environment. This review provides the update on the in vitro, in vivo, and ex vivo models used in DR research, focusing on their features, advantages, and limitations.

Matched MeSH terms: Retina/pathology
Retinopathy in acute leukaemia at initial diagnosis: correlation of fundus lesions and haematological parameters

Reddy SC, Jackson N

Acta Ophthalmol Scand, 2004 Feb;82(1):81-5.
PMID: 14738490

PURPOSE: To determine the prevalence of retinal changes in newly diagnosed acute leukaemia patients, and to establish the relationship between retinal lesions and haematological parameters in these patients.
METHODS: A total of 127 patients with acute leukaemia (myeloid and lymphoid), of both genders, aged between 13 and 77 years, were examined by an ophthalmologist for retinal changes using direct/indirect ophthalmoscopy within 2 days of diagnosis before starting chemotherapy.
RESULTS: Retinal lesions were seen in 62 cases (49%), with intraretinal haemorrhages being the most common lesion (42%). A high white blood cell count was significantly associated with intraretinal haemorrhages (p = 0.04) and white-centred haemorrhages (p = 0.001), while a low platelet count was significantly associated with intraretinal haemorrhages (p = 0.03) in acute myeloid leukaemia patients.
CONCLUSIONS: A high white blood cell count may be considered as important as a low platelet count in the pathogenesis of leukaemic retinopathy.

Matched MeSH terms: Retina/pathology*
Anterior and posterior segment changes in rat eyes with chronic steroid administration and their responsiveness to antiglaucoma drugs

Razali N, Agarwal R, Agarwal P, Kapitonova MY, Kannan Kutty M, Smirnov A, et al.

Eur J Pharmacol, 2015 Feb 15;749:73-80.
PMID: 25481859 DOI: 10.1016/j.ejphar.2014.11.029

Steroid-induced ocular hypertension (SIOH) is associated with topical and systemic use of steroids. However, SIOH-associated anterior and posterior segment morphological changes in rats have not been described widely. Here we describe the pattern of intraocular pressure (IOP) changes, quantitative assessment of trabecular meshwork (TM) and retinal morphological changes and changes in retinal redox status in response to chronic dexamethasone treatment in rats. We also evaluated the responsiveness of steroid-pretreated rat eyes to 5 different classes of antiglaucoma drugs that act by different mechanisms. Up to 80% of dexamethasone treated animals achieved significant and sustained IOP elevation. TM thickness was significantly increased and number of TM cells was significantly reduced in SIOH rats compared to the vehicle-treated rats. Quantitative assessment of retinal morphology showed significantly reduced thickness of ganglion cell layer (GCL) and inner retina (IR) in SIOH rats compared to vehicle-treated rats. Estimation of retinal antioxidants including catalase, superoxide dismutase and glutathione showed significantly increased retinal oxidative stress in SIOH animals. Furthermore, steroid-treated eyes showed significant IOP lowering in response to treatment with 5 different drug classes. This indicated the ability of SIOH eyes to respond to drugs acting by different mechanisms. In conclusion, SIOH was associated with significant morphological changes in TM and retina and retinal redox status. Additionally, SIOH eyes also showed IOP lowering in response to drugs that act by different mechanisms of action. Hence, SIOH rats appear to be an inexpensive and noninvasive model for studying the experimental antiglaucoma drugs for IOP lowering and neuroprotective effects.

Matched MeSH terms: Retina/pathology
Topical trans-resveratrol ameliorates steroid-induced anterior and posterior segment changes in rats

Razali N, Agarwal R, Agarwal P, Tripathy M, Kapitonova MY, Kutty MK, et al.

Exp Eye Res, 2016 Feb;143:9-16.
PMID: 26424219 DOI: 10.1016/j.exer.2015.09.014

Steroid-induced hypertension and glaucoma is associated with increased extracellular meshwork (ECM) deposition in trabecular meshwork (TM). Previous studies have shown that single drop application of trans-resveratrol lowers IOP in steroid-induced ocular hypertensive (SIOH) rats. This IOP lowering is attributed to activation of adenosine A1 receptors, which may lead to increased matrix metalloproteinase (MMP)-2 activity. This study evaluated the effect of repeated topical application of trans-resveratrol for 21 days in SIOH animals on IOP, changes in MMP-2 level in aqueous humor, trabecular meshwork and retinal morphology and retinal redox status. We observed that treatment with trans-resveratrol results in significant and sustained IOP reduction in SIOH rats. This IOP reduction is associated with significantly higher aqueous humor total MMP-2 level; significantly reduced TM thickness and increased number of TM cells. Treatment with trans-resveratrol also significantly increased ganglion cell layer (GCL) thickness, the linear cell density in the GCL and inner retina thickness; and significantly reduced retinal oxidative stress compared to the SIOH vehicle-treated group. In conclusion, repeated dose topical application of trans-resveratrol produces sustained IOP lowering effect, which is associated with increased level of aqueous humor MMP-2, normalization of TM and retinal morphology and restoration of retinal redox status.

Matched MeSH terms: Retina/pathology*
Mass mortality of hatchery-produced larvae of Asian seabass, Lates calcarifer (Bloch), associated with viral nervous necrosis in Sabah, Malaysia

Ransangan J, Manin BO

Vet Microbiol, 2010 Sep 28;145(1-2):153-7.
PMID: 20427132 DOI: 10.1016/j.vetmic.2010.03.016

Culture of Asian seabass, Lates calcarifer (Bloch) is a popular aquaculture activity in Malaysia. This fish is in high demand and fetches a good price in the local market. The seed for this fish is commercially produced by induced spawning in hatcheries. However, the seed supply is affected by frequent mass mortality of larvae aged between 15 and 60 dph. The clinical signs shown by the affected larvae include lethargy, loss of appetite, uncoordinated swimming, unusual spiral movement pattern and dark coloration. Histological examination of brain and eye of the affected specimens revealed extensive cell vacuolation in larvae aged 15-25 dph. Partial nucleotide sequence of the nervous necrosis virus coat protein gene of the affected larvae showed 94.0-96.1% homology to the nucleotide sequences of coat protein gene from nervous necrosis virus isolated from other countries in the Southeast Asia and Australia. This study provides scientific evidence based on molecular technique that many episodes of mass mortality in seabass larvae in Sabah is associated with the viral nervous necrosis. Because no effective treatment has been reported for this infection, stringent biosecurity measures must be adopted for exclusion of the pathogen from the culture system.

Matched MeSH terms: Retina/pathology
Secretory proteostasis of the retinal pigmented epithelium: Impairment links to age-related macular degeneration

Paraoan L, Sharif U, Carlsson E, Supharattanasitthi W, Mahmud NM, Kamalden TA, et al.

Prog Retin Eye Res, 2020 11;79:100859.
PMID: 32278708 DOI: 10.1016/j.preteyeres.2020.100859

Secretory proteostasis integrates protein synthesis, processing, folding and trafficking pathways that are essential for efficient cellular secretion. For the retinal pigment epithelium (RPE), secretory proteostasis is of vital importance for the maintenance of the structural and functional integrity of apical (photoreceptors) and basal (Bruch's membrane/choroidal blood supply) sides of the environment it resides in. This integrity is achieved through functions governed by RPE secreted proteins, which include extracellular matrix modelling/remodelling, angiogenesis and immune response modulation. Impaired RPE secretory proteostasis affects not only the extracellular environment, but leads to intracellular protein aggregation and ER-stress with subsequent cell death. Ample recent evidence implicates dysregulated proteostasis as a key factor in the development of age-related macular degeneration (AMD), the leading cause of blindness in the developed world, and research aiming to characterise the roles of various proteins implicated in AMD-associated dysregulated proteostasis unveiled unexpected facets of the mechanisms involved in degenerative pathogenesis. This review analyses cellular processes unveiled by the study of the top 200 transcripts most abundantly expressed by the RPE/choroid in the light of the specialised secretory nature of the RPE. Functional roles of these proteins and the mechanisms of their impaired secretion, due to age and genetic-related causes, are analysed in relation to AMD development. Understanding the importance of RPE secretory proteostasis in relation to maintaining retinal health and how it becomes impaired in disease is of paramount importance for the development and assessment of future therapeutic advancements involving gene and cell therapies.

Matched MeSH terms: Retina/pathology
Fulltext The structural effect of intravitreal Brilliant blue G and Indocyanine green in rats eyes

Ooi YL, Khang TF, Naidu M, Fong KC

Eye (Lond), 2013 Mar;27(3):425-31.
PMID: 23196646 DOI: 10.1038/eye.2012.260

To compare the potential retinal toxicity of two commercially Brilliant blue G dyes (Brilliant Peel and Ocublue Plus) and Indocyanine green (ICG) at usual clinical concentration.

Matched MeSH terms: Retina/pathology
Triple Vessel Coronary Artery Disease and Retinal Nerve Fibre Layer Thickness

Neoh YL, Neoh PF, Salleh A, Yusof ZB, Gurusamy B, Ahmad Tajudin LS

Ann Acad Med Singap, 2018 06;47(6):226-229.
PMID: 30019068
Matched MeSH terms: Retina/pathology*
Local configuration pattern features for age-related macular degeneration characterization and classification

Mookiah MR, Acharya UR, Fujita H, Koh JE, Tan JH, Noronha K, et al.

Comput Biol Med, 2015 Aug;63:208-18.
PMID: 26093788 DOI: 10.1016/j.compbiomed.2015.05.019

Age-related Macular Degeneration (AMD) is an irreversible and chronic medical condition characterized by drusen, Choroidal Neovascularization (CNV) and Geographic Atrophy (GA). AMD is one of the major causes of visual loss among elderly people. It is caused by the degeneration of cells in the macula which is responsible for central vision. AMD can be dry or wet type, however dry AMD is most common. It is classified into early, intermediate and late AMD. The early detection and treatment may help one to stop the progression of the disease. Automated AMD diagnosis may reduce the screening time of the clinicians. In this work, we have introduced LCP to characterize normal and AMD classes using fundus images. Linear Configuration Coefficients (CC) and Pattern Occurrence (PO) features are extracted from fundus images. These extracted features are ranked using p-value of the t-test and fed to various supervised classifiers viz. Decision Tree (DT), Nearest Neighbour (k-NN), Naive Bayes (NB), Probabilistic Neural Network (PNN) and Support Vector Machine (SVM) to classify normal and AMD classes. The performance of the system is evaluated using both private (Kasturba Medical Hospital, Manipal, India) and public domain datasets viz. Automated Retinal Image Analysis (ARIA) and STructured Analysis of the Retina (STARE) using ten-fold cross validation. The proposed approach yielded best performance with a highest average accuracy of 97.78%, sensitivity of 98.00% and specificity of 97.50% for STARE dataset using 22 significant features. Hence, this system can be used as an aiding tool to the clinicians during mass eye screening programs to diagnose AMD.

Matched MeSH terms: Retina/pathology*
Spectrum of germ-line RB1 gene mutations in Malaysian patients with retinoblastoma

Mohd Khalid MK, Yakob Y, Md Yasin R, Wee Teik K, Siew CG, Rahmat J, et al.

Mol Vis, 2015;21:1185-90.
PMID: 26539030

The availability of molecular genetic testing for retinoblastoma (RB) in Malaysia has enabled patients with a heritable predisposition to the disease to be identified, which thus improves the clinical management of these patients and their families. In this paper, we presented our strategy for performing molecular genetic testing of the RB1 gene and the findings from our first 2 years of starting this service.

Matched MeSH terms: Retina/pathology
Fulltext Analysis of the association between CFH Y402H polymorphism and response to intravitreal ranibizumab in patients with neovascular age-related macular degeneration (nAMD)

Mohamad NA, Ramachandran V, Ismail P, Mohd Isa H, Chan YM, Ngah NF, et al.

Bosn J Basic Med Sci, 2018 Aug 01;18(3):260-267.
PMID: 29579408 DOI: 10.17305/bjbms.2018.2493

Pharmacogenetic studies indicate that a variable response to anti-vascular endothelial growth factor (VEGF) therapy in patients with neovascular form of AMD (nAMD) may be due to polymorphisms in the complement factor H gene (CFH). This study is the first to investigate the association between CFH Y402H polymorphism and the response to ranibizumab therapy in Malaysian patients with nAMD. We included 134 patients with nAMD, examined between September 2014 and February 2016. The diagnosis of nAMD was confirmed by ophthalmologic examination, before ranibizumab therapy was started. Each patient received an intravitreal injection of 0.5 mg/0.05 ml ranibizumab following a treat-and-extend (TE) regimen. Best-corrected visual acuity (BCVA) and central retinal thickness (CRT) were recorded after 3 and 6 months following the first injection and compared with the baseline values. Genotyping of Y402H (rs1061170) polymorphism was performed using PCR-RFLP and the amplified product was digested with MluCI restriction enzyme. Association between the Y402H genotypes and response to treatment was determined by a logistic regression analysis of responder (n = 49) and non-responder (n = 84) group. Significantly worse mean BCVA was observed for the CC genotype compared to the TT + CT genotype in the total sample after 6-month follow-up (p = 0.018). Comparing the baseline and 6-month point measurements, improved mean BCVA was observed in responder group, while worse mean BCVA was recorded for non-responder group. However, our regression analysis, adjusted for confounding factors, showed no significant association between the Y402H genotypes and response to treatment in nAMD patients under the recessive model (p > 0.05). Overall, our results suggest that factors other than Y402H polymorphism may be involved in the progression of nAMD after treatment with anti-VEGF agents, in Malaysian population.

Matched MeSH terms: Retina/pathology
Sustained Connexin43 Mimetic Peptide Release From Loaded Nanoparticles Reduces Retinal and Choroidal Photodamage

Mat Nor N, Guo CX, Rupenthal ID, Chen YS, Green CR, Acosta ML

Invest Ophthalmol Vis Sci, 2018 07 02;59(8):3682-3693.
PMID: 30029255 DOI: 10.1167/iovs.17-22829

Purpose: To evaluate the long-term effect on inflammation and inflammasome activation of intravitreally delivered connexin43 mimetic peptide (Cx43MP) in saline or incorporated within nanoparticles (NPs) for the treatment of the light-damaged rat eye.
Methods: Light-induced damage to the retina was created by exposure of adult albino Sprague-Dawley rats to intense light for 24 hours. A single dose of Cx43MP, Cx43MP-NPs, or saline was injected intravitreally at 2 hours after onset of light damage. Fluorescein isothiocyanate (FITC)-labelled Cx43MP-NPs were intravitreally injected to confirm delivery into the retina. Electroretinogram (ERG) recordings were performed at 24 hours, 1 week, and 2 weeks post cessation of light damage. The retinal and choroidal layers were analyzed in vivo using optical coherence tomography (OCT) and immunohistochemistry was performed on harvested tissues using glial fibrillary acidic protein (GFAP), leukocyte common antigen (CD45), and Cx43 antibodies.
Results: FITC was visualized 30 minutes after injection in the ganglion cell layer and in the choroid. Cx43MP and Cx43MP-NP treatments improved a-wave and b-wave function of the ERG compared with saline-injected eyes at 1 week and 2 weeks post treatment, and prevented photoreceptor loss by 2 weeks post treatment. Inflammation was also reduced and this was in parallel with downregulation of Cx43 expression.
Conclusions: The slow release of Cx43MP incorporated into NPs is more effective at treating retinal injury than a single dose of native Cx43MP in solution by reducing inflammation and maintaining both retinal structure and function. This NP preparation has clinical relevance as it reduces possible ocular complications associated with repeated intravitreal injections.

Matched MeSH terms: Retina/pathology*

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