Displaying publications 1 - 20 of 61 in total

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  1. Ooi AZH, Embong Z, Abd Hamid AI, Zainon R, Wang SL, Ng TF, et al.
    Sensors (Basel), 2021 Sep 24;21(19).
    PMID: 34640698 DOI: 10.3390/s21196380
    Optometrists, ophthalmologists, orthoptists, and other trained medical professionals use fundus photography to monitor the progression of certain eye conditions or diseases. Segmentation of the vessel tree is an essential process of retinal analysis. In this paper, an interactive blood vessel segmentation from retinal fundus image based on Canny edge detection is proposed. Semi-automated segmentation of specific vessels can be done by simply moving the cursor across a particular vessel. The pre-processing stage includes the green color channel extraction, applying Contrast Limited Adaptive Histogram Equalization (CLAHE), and retinal outline removal. After that, the edge detection techniques, which are based on the Canny algorithm, will be applied. The vessels will be selected interactively on the developed graphical user interface (GUI). The program will draw out the vessel edges. After that, those vessel edges will be segmented to bring focus on its details or detect the abnormal vessel. This proposed approach is useful because different edge detection parameter settings can be applied to the same image to highlight particular vessels for analysis or presentation.
    Matched MeSH terms: Fundus Oculi
  2. Tang MCS, Teoh SS, Ibrahim H, Embong Z
    Sensors (Basel), 2021 Aug 06;21(16).
    PMID: 34450766 DOI: 10.3390/s21165327
    Proliferative Diabetic Retinopathy (PDR) is a severe retinal disease that threatens diabetic patients. It is characterized by neovascularization in the retina and the optic disk. PDR clinical features contain highly intense retinal neovascularization and fibrous spreads, leading to visual distortion if not controlled. Different image processing techniques have been proposed to detect and diagnose neovascularization from fundus images. Recently, deep learning methods are getting popular in neovascularization detection due to artificial intelligence advancement in biomedical image processing. This paper presents a semantic segmentation convolutional neural network architecture for neovascularization detection. First, image pre-processing steps were applied to enhance the fundus images. Then, the images were divided into small patches, forming a training set, a validation set, and a testing set. A semantic segmentation convolutional neural network was designed and trained to detect the neovascularization regions on the images. Finally, the network was tested using the testing set for performance evaluation. The proposed model is entirely automated in detecting and localizing neovascularization lesions, which is not possible with previously published methods. Evaluation results showed that the model could achieve accuracy, sensitivity, specificity, precision, Jaccard similarity, and Dice similarity of 0.9948, 0.8772, 0.9976, 0.8696, 0.7643, and 0.8466, respectively. We demonstrated that this model could outperform other convolutional neural network models in neovascularization detection.
    Matched MeSH terms: Fundus Oculi
  3. Shariff S, Teo KSS, Hitam WHW
    Rom J Ophthalmol, 2021 6 29;65(2):196-200.
    PMID: 34179588 DOI: 10.22336/rjo.2021.39
    Objective: To report a case of choroidal mass secondary to mucinous cystadenocarcinoma of ovary in a young woman. Method: A case report. Result: A 21-year-old woman presented with insidious painless, progressive, central scotoma of the right eye for 5 weeks. She was disease free for 9 years after she underwent right salpingo-oophorectomy for her mucinous cystadenocarcinoma of right ovary. She completed 6 cycles of chemotherapy regimen. On presentation, her visual acuity was counting finger in the right eye and 6/ 6 in the left eye. Both anterior segments were unremarkable. Fundus examination of the right eye showed multiple choroidal masses with the largest in the temporal to fovea. Generally, she was well. Her tumor markers were raised. Urgent Computed Tomography (CT) Scan of thorax, abdomen and pelvis showed multiple distance metastases. She was referred to the gynecology team. She was scheduled for chemotherapy. However, she defaulted the treatment. 3 months after that, her general condition deteriorated. She developed bilateral internal jugular vein thrombosis and massive right pleural effusion. She passed away due to that complication. Conclusion: Choroidal metastasis from primary ovary carcinoma is very rare. Ocular symptoms can be the first presenting features to a life-threatening condition.
    Matched MeSH terms: Fundus Oculi
  4. Lim TH, Wai YZ, Chong JC
    J Med Case Rep, 2021 May 12;15(1):267.
    PMID: 33980269 DOI: 10.1186/s13256-021-02826-1
    BACKGROUND: Frosted branch angiitis (FBA) is an uncommon ocular sign with multiple causes. With the recent outbreak of coronavirus disease 2019 (COVID-19), many cases of ocular manifestation in association with this disease have been reported. However, as yet we have no complete understanding of this condition. We report here the first case of FBA in a human immunodeficiency virus-infected patient with coexisting cytomegalovirus (CMV) and COVID-19 infection.

    CASE PRESENTATION: A 33-year-old Malay man with underlying acquired immunodeficiency syndrome receiving highly active antiretroviral therapy was referred to the Opthalmology Department with complaints of blurry vision for the past 2 months. He had tested positive for and been diagnosed with COVID-19 1 month previously. Clinical examination of the fundus revealed extensive perivascular sheathing of both the artery and vein suggestive of FBA in the right eye. Laboratory testing of nasal swabs for COVID-19 polymerase chain reaction (PCR) and serum CMV antibody were positive. The patient was then admitted to the COVID-19 ward and treated with intravenous ganciclovir.

    CONCLUSION: Clinicians should be aware of and take the necessary standard precautions for possible coexistence of COVID-19 in an immunocompromised patient presenting with blurred vision, eye redness, dry eye and foreign body sensation despite the absence of clinical features suggestive of COVID-19. Whether FBA is one of the ocular signs of co-infection of COVID-19 and CMV remains unknown. Further studies are needed to provide more information on ocular signs presented in patients with concurrent COVID-19 and CMV infections.

    Matched MeSH terms: Fundus Oculi
  5. Teow Kheng Leong K, Abu Kassim SNA, Sidhu JK, Zohari Z, Sivalingam T, Ramasamy S, et al.
    BMC Ophthalmol, 2021 Mar 09;21(1):128.
    PMID: 33750348 DOI: 10.1186/s12886-021-01882-x
    BACKGROUND: The current practice for new-born eye examination by an Ophthalmologist in Malaysian hospitals is limited to only preterm new-borns, syndromic or ill infants. Healthy term new-borns are usually discharged without a thorough eye examination. This study is aimed at determining the proportion and types of ocular abnormalities detected in purportedly healthy term new-borns.

    METHOD: This cross-sectional study is comprised of 203 participants, all purportedly healthy term new-born infants from the Obstetrics and Gynaecology ward at Hospital Kuala Lumpur over a 6 months period. The examination list includes external eye examination, red reflex test, and fundus imaging using a wide-field digital retinal imaging system (Phoenix Clinical ICON Paediatric Retinal Camera) by a trained Investigator. The pathologies detected were documented. The results were compared and correlated with similar studies published in the literature previously.

    RESULTS: Total ocular abnormalities were detected in 34% of the infants. The most common finding was retinal haemorrhage in 29.6% of the infants, of which 53.3% occurred bilaterally. Spontaneous vaginal delivery (SVD) remained the greatest risk factor which has nearly 3.5 times higher risk of new-borns developing retinal haemorrhage compared to Lower Segment Caesarean Section (LSCS). There was a 6% increased likelihood of developing retinal haemorrhage for every 1-min increment in the duration of 2nd stage of labour.

    CONCLUSION: Universal eye screening for all new-borns using a wide-field digital imaging system is realistically possible, safe, and useful in detecting posterior segment disorders. The most common abnormality detected is retinal haemorrhage.

    Matched MeSH terms: Fundus Oculi
  6. Ab Kahar MEPI, Muhammed J, Hitam WHW, Husin A
    Turk J Ophthalmol, 2020 12 29;50(6):371-376.
    PMID: 33389938 DOI: 10.4274/tjo.galenos.2020.83873
    Bartonella henselae is a recognized cause of neuroretinitis in cat scratch disease. Meanwhile, polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, skin changes (POEMS) syndrome with Castleman disease (evidence of lymph node hyperplasia), is a chronic debilitating condition that predisposes to various superimposed infections. B. henselae neuroretinitis implicated in POEMS syndrome has not been reported previously. A 34-year-old asymptomatic man was referred for an eye assessment. Examination showed visual acuity of 6/18 in the right eye and 6/24 in the left eye. On fundus examination, both eyes exhibited typical features of neuroretinitis (optic disc swelling and incomplete macular star). There was otherwise no vitritis or chorioretinitis. Serology for B. henselae revealed high immunoglobulin M (IgM) titer (1:96) indicative of acute disease, and positive immunoglobulin G (IgG) (1:156). He was treated with oral azithromycin for 6 weeks and a short course of oral prednisolone. Subsequently, the visual acuity in both eyes improved with resolution of macular star. However, both optic discs remained swollen.
    Matched MeSH terms: Fundus Oculi
  7. Lim TH, Lai TYY, Takahashi K, Wong TY, Chen LJ, Ruamviboonsuk P, et al.
    JAMA Ophthalmol, 2020 09 01;138(9):935-942.
    PMID: 32672800 DOI: 10.1001/jamaophthalmol.2020.2443
    Importance: The 2-year efficacy and safety of combination therapy of ranibizumab administered together with verteporfin photodynamic therapy (vPDT) compared with ranibizumab monotherapy in participants with polypoidal choroidal vasculopathy (PCV) are unclear.

    Objective: To compare treatment outcomes of ranibizumab, 0.5 mg, plus prompt vPDT combination therapy with ranibizumab, 0.5 mg, monotherapy in participants with PCV for 24 months.

    Design, Setting, and Participants: This 24-month, phase IV, double-masked, multicenter, randomized clinical trial (EVEREST II) was conducted among Asian participants from August 7, 2013, to March 2, 2017, with symptomatic macular PCV confirmed using indocyanine green angiography.

    Interventions: Participants (N = 322) were randomized 1:1 to ranibizumab, 0.5 mg, plus vPDT (combination therapy group; n = 168) or ranibizumab, 0.5 mg, plus sham PDT (monotherapy group; n = 154). All participants received 3 consecutive monthly ranibizumab injections, followed by a pro re nata regimen. Participants also received vPDT (combination group) or sham PDT (monotherapy group) on day 1, followed by a pro re nata regimen based on the presence of active polypoidal lesions.

    Main Outcomes and Measures: Evaluation of combination therapy vs monotherapy at 24 months in key clinical outcomes, treatment exposure, and safety. Polypoidal lesion regression was defined as the absence of indocyanine green hyperfluorescence of polypoidal lesions.

    Results: Among 322 participants (mean [SD] age, 68.1 [8.8] years; 225 [69.9%] male), the adjusted mean best-corrected visual acuity (BCVA) gains at month 24 were 9.6 letters in the combination therapy group and 5.5 letters in the monotherapy group (mean difference, 4.1 letters; 95% CI, 1.0-7.2 letters; P = .005), demonstrating that combination therapy was superior to monotherapy by the BCVA change from baseline to month 24. Combination therapy was superior to monotherapy in terms of complete polypoidal lesion regression at month 24 (81 of 143 [56.6%] vs 23 of 86 [26.7%] participants; P 

    Matched MeSH terms: Fundus Oculi
  8. Raghavendra U, Gudigar A, Bhandary SV, Rao TN, Ciaccio EJ, Acharya UR
    J Med Syst, 2019 Jul 30;43(9):299.
    PMID: 31359230 DOI: 10.1007/s10916-019-1427-x
    Glaucoma is a type of eye condition which may result in partial or consummate vision loss. Higher intraocular pressure is the leading cause for this condition. Screening for glaucoma and early detection can avert vision loss. Computer aided diagnosis (CAD) is an automated process with the potential to identify glaucoma early through quantitative analysis of digital fundus images. Preparing an effective model for CAD requires a large database. This study presents a CAD tool for the precise detection of glaucoma using a machine learning approach. An autoencoder is trained to determine effective and important features from fundus images. These features are used to develop classes of glaucoma for testing. The method achieved an F - measure value of 0.95 utilizing 1426 digital fundus images (589 control and 837 glaucoma). The efficacy of the system is evident, and is suggestive of its possible utility as an additional tool for verification of clinical decisions.
    Matched MeSH terms: Fundus Oculi*
  9. Maheshwari S, Kanhangad V, Pachori RB, Bhandary SV, Acharya UR
    Comput Biol Med, 2019 Feb;105:72-80.
    PMID: 30590290 DOI: 10.1016/j.compbiomed.2018.11.028
    BACKGROUND AND OBJECTIVE: Glaucoma is a ocular disorder which causes irreversible damage to the retinal nerve fibers. The diagnosis of glaucoma is important as it may help to slow down the progression. The available clinical methods and imaging techniques are manual and require skilled supervision. For the purpose of mass screening, an automated system is needed for glaucoma diagnosis which is fast, accurate, and helps in reducing the burden on experts.

    METHODS: In this work, we present a bit-plane slicing (BPS) and local binary pattern (LBP) based novel approach for glaucoma diagnosis. Firstly, our approach separates the red (R), green (G), and blue (B) channels from the input color fundus image and splits the channels into bit planes. Secondly, we extract LBP based statistical features from each of the bit planes of the individual channels. Thirdly, these features from the individual channels are fed separately to three different support vector machines (SVMs) for classification. Finally, the decisions from the individual SVMs are fused at the decision level to classify the input fundus image into normal or glaucoma class.

    RESULTS: Our experimental results suggest that the proposed approach is effective in discriminating normal and glaucoma cases with an accuracy of 99.30% using 10-fold cross validation.

    CONCLUSIONS: The developed system is ready to be tested on large and diverse databases and can assist the ophthalmologists in their daily screening to confirm their diagnosis, thereby increasing accuracy of diagnosis.

    Matched MeSH terms: Fundus Oculi
  10. Sherina, Q., Rosiah, M., Mushawiahti, M.
    Medicine & Health, 2019;14(2):271-277.
    MyJurnal
    Acute retinal necrosis (ARN) is a rare, blinding disease that typically affects adults. However, in this case report, we highlight the diagnosis, management and outcome of herpes simplex acute retinal necrosis in a 13-year-old healthy girl, who presented with painful right eye, redness and blurring of vision for one week. Examination of the right eye showed features of granulomatous panuveitis. Optic disc was swollen and retina appeared pale. There were multiple patches of retinitis and haemorrhages at mid-periphery of the fundus with inferior serous detachment observed. Rapidly progressive inflammation in just four days along with secondary cataract that obscured fundus view, imposed greater challenge to the diagnosis and management. Intravenous acyclovir 300mg, 3 times a day was initiated promptly while vitreous fluid was sent for polymerase chain reaction, which identified Herpes Simplex Virus-1. Inflammation improved, but she developed vitreous haemorrhage secondary to proliferative retinopathy, which required panretinal photocoagulation. ARN is therefore, principally a clinical diagnosis and high index of suspicion is crucial particularly, in children for prompt diagnosis and treatment. Complications should also be addressed timely to improve the chances of preserving vision.

    Matched MeSH terms: Fundus Oculi
  11. Porwal P, Pachade S, Kokare M, Giancardo L, Mériaudeau F
    Comput Biol Med, 2018 11 01;102:200-210.
    PMID: 30308336 DOI: 10.1016/j.compbiomed.2018.09.028
    Age-related Macular Degeneration (AMD) and Diabetic Retinopathy (DR) are the most prevalent diseases responsible for visual impairment in the world. This work investigates discrimination potential in the texture of color fundus images to distinguish between diseased and healthy cases by avoiding the prior lesion segmentation step. It presents a retinal background characterization approach and explores the potential of Local Tetra Patterns (LTrP) for texture classification of AMD, DR and Normal images. Five different experiments distinguishing between DR - normal, AMD - normal, DR - AMD, pathological - normal and AMD - DR - normal cases were conducted and validated using the proposed approach, and promising results were obtained. For all five experiments, different classifiers namely, AdaBoost, c4.5, logistic regression, naive Bayes, neural network, random forest and support vector machine were tested. We experimented with three public datasets, ARIA, STARE and E-Optha. Further, the performance of LTrP is compared with other texture descriptors, such as local phase quantization, local binary pattern and local derivative pattern. In all cases, the proposed method obtained the area under the receiver operating characteristic curve and f-score values higher than 0.78 and 0.746 respectively. It was found that both performance measures achieve over 0.995 for DR and AMD detection using a random forest classifier. The obtained results suggest that the proposed technique can discriminate retinal disease using texture information and has potential to be an important component for an automated screening solution for retinal images.
    Matched MeSH terms: Fundus Oculi
  12. Hagiwara Y, Koh JEW, Tan JH, Bhandary SV, Laude A, Ciaccio EJ, et al.
    Comput Methods Programs Biomed, 2018 Oct;165:1-12.
    PMID: 30337064 DOI: 10.1016/j.cmpb.2018.07.012
    BACKGROUND AND OBJECTIVES: Glaucoma is an eye condition which leads to permanent blindness when the disease progresses to an advanced stage. It occurs due to inappropriate intraocular pressure within the eye, resulting in damage to the optic nerve. Glaucoma does not exhibit any symptoms in its nascent stage and thus, it is important to diagnose early to prevent blindness. Fundus photography is widely used by ophthalmologists to assist in diagnosis of glaucoma and is cost-effective.

    METHODS: The morphological features of the disc that is characteristic of glaucoma are clearly seen in the fundus images. However, manual inspection of the acquired fundus images may be prone to inter-observer variation. Therefore, a computer-aided detection (CAD) system is proposed to make an accurate, reliable and fast diagnosis of glaucoma based on the optic nerve features of fundus imaging. In this paper, we reviewed existing techniques to automatically diagnose glaucoma.

    RESULTS: The use of CAD is very effective in the diagnosis of glaucoma and can assist the clinicians to alleviate their workload significantly. We have also discussed the advantages of employing state-of-art techniques, including deep learning (DL), when developing the automated system. The DL methods are effective in glaucoma diagnosis.

    CONCLUSIONS: Novel DL algorithms with big data availability are required to develop a reliable CAD system. Such techniques can be employed to diagnose other eye diseases accurately.

    Matched MeSH terms: Fundus Oculi
  13. Aslam TM, Zaki HR, Mahmood S, Ali ZC, Ahmad NA, Thorell MR, et al.
    Am J Ophthalmol, 2018 Jan;185:94-100.
    PMID: 29101008 DOI: 10.1016/j.ajo.2017.10.015
    PURPOSE: To develop a neural network for the estimation of visual acuity from optical coherence tomography (OCT) images of patients with neovascular age-related macular degeneration (AMD) and to demonstrate its use to model the impact of specific controlled OCT changes on vision.

    DESIGN: Artificial intelligence (neural network) study.

    METHODS: We assessed 1400 OCT scans of patients with neovascular AMD. Fifteen physical features for each eligible OCT, as well as patient age, were used as input data and corresponding recorded visual acuity as the target data to train, validate, and test a supervised neural network. We then applied this network to model the impact on acuity of defined OCT changes in subretinal fluid, subretinal hyperreflective material, and loss of external limiting membrane (ELM) integrity.

    RESULTS: A total of 1210 eligible OCT scans were analyzed, resulting in 1210 data points, which were each 16-dimensional. A 10-layer feed-forward neural network with 1 hidden layer of 10 neurons was trained to predict acuity and demonstrated a root mean square error of 8.2 letters for predicted compared to actual visual acuity and a mean regression coefficient of 0.85. A virtual model using this network demonstrated the relationship of visual acuity to specific, programmed changes in OCT characteristics. When ELM is intact, there is a shallow decline in acuity with increasing subretinal fluid but a much steeper decline with equivalent increasing subretinal hyperreflective material. When ELM is not intact, all visual acuities are reduced. Increasing subretinal hyperreflective material or subretinal fluid in this circumstance reduces vision further still, but with a smaller gradient than when ELM is intact.

    CONCLUSIONS: The supervised machine learning neural network developed is able to generate an estimated visual acuity value from OCT images in a population of patients with AMD. These findings should be of clinical and research interest in macular degeneration, for example in estimating visual prognosis or highlighting the importance of developing treatments targeting more visually destructive pathologies.

    Matched MeSH terms: Fundus Oculi
  14. Koh JEW, Ng EYK, Bhandary SV, Hagiwara Y, Laude A, Acharya UR
    Comput Biol Med, 2018 01 01;92:204-209.
    PMID: 29227822 DOI: 10.1016/j.compbiomed.2017.11.019
    Untreated age-related macular degeneration (AMD), diabetic retinopathy (DR), and glaucoma may lead to irreversible vision loss. Hence, it is essential to have regular eye screening to detect these eye diseases at an early stage and to offer treatment where appropriate. One of the simplest, non-invasive and cost-effective techniques to screen the eyes is by using fundus photo imaging. But, the manual evaluation of fundus images is tedious and challenging. Further, the diagnosis made by ophthalmologists may be subjective. Therefore, an objective and novel algorithm using the pyramid histogram of visual words (PHOW) and Fisher vectors is proposed for the classification of fundus images into their respective eye conditions (normal, AMD, DR, and glaucoma). The proposed algorithm extracts features which are represented as words. These features are built and encoded into a Fisher vector for classification using random forest classifier. This proposed algorithm is validated with both blindfold and ten-fold cross-validation techniques. An accuracy of 90.06% is achieved with the blindfold method, and highest accuracy of 96.79% is obtained with ten-fold cross-validation. The highest classification performance of our system shows the potential of deploying it in polyclinics to assist healthcare professionals in their initial diagnosis of the eye. Our developed system can reduce the workload of ophthalmologists significantly.
    Matched MeSH terms: Fundus Oculi
  15. Rathna, R., Mushawiahti, M., Bastion, M.L.C., Masdar, A., Ropilah, A.R.
    Medicine & Health, 2018;13(1):243-250.
    MyJurnal
    Central retinal vein occlusion (CRVO) is uncommon among young patients. Among the young adults, CRVO tends to be more benign with good visual prognosis. Macular oedema secondary to retinal vein occlusion is a relatively common complication that is currently being treated with intravitreal anti vascular endothelial growth factor with good outcomes. Other complications include lamellar hole, vitreous hemorrhage and neovascular glaucoma. We report a case of central retinal vein occlusion in a young female who presented to us with the complaint of blurring of vision in the left eye for four months. Fundus examination showed hyperemic optic disc, dilated tortuous vein, extensive retinal hemorrhages with macular oedema and an inferior shallow exudative retinal detachment. One month later, intravitreal ranibizumab injection for her macular oedema, a full thickness macular hole developed with reduction of macular oedema. Four months later, the hole spontaneously closed but her macular oedema persisted. The possibility of rare complications like exudative retinal detachment and full thickness macular hole must be kept in mind to ensure early detection and effective management is provided to preserve vision.
    Matched MeSH terms: Fundus Oculi
  16. Azhan, A., Mutasim, H., Abdul-Hadi, R., Khairul-Anwar, I., Zunaina, E.
    MyJurnal
    Macular branch retinal vein occlusion (BRVO), a type of retinal vein occlusion, is rarely recognised as a distinct entity. Macular BRVO has unique clinical features and different natural courses than the major BRVO. We report a case of a young patient with macular BRVO with macular oedema who was successfully treated with intravitreal ranibizumab injection. A 43 year-old Chinese man with no underlying medical illness presented with 2 weeks history of left eye painless reduced central vision which was worsening over time. On examination, his left eye visual acuity was 6/30 and Amsler chart drawing showed a lower central scotoma. Dilated fundus examination found marked flame-shaped retinal hemorrhages with cotton wool spot over the superior macular area bounded superiorly by superior arcade and macular thickening. An optical coherence tomography revealed cystoid macular oedema; and fundus fluorescein angiography showed occlusion of a small venous branch draining a superior part of macula to superior temporal venous arcade. A complete medical investigation found that he has hypertriglyceridemia and he was managed accordingly. His vision had improved to 6/6 after receiving 3 injections of intravitreal ranibizumab with no residual central scotoma and complete resolution of macular oedema.
    Matched MeSH terms: Fundus Oculi
  17. Kipli K, Hoque ME, Lim LT, Mahmood MH, Sahari SK, Sapawi R, et al.
    Comput Math Methods Med, 2018;2018:4019538.
    PMID: 30065780 DOI: 10.1155/2018/4019538
    Digital image processing is one of the most widely used computer vision technologies in biomedical engineering. In the present modern ophthalmological practice, biomarkers analysis through digital fundus image processing analysis greatly contributes to vision science. This further facilitates developments in medical imaging, enabling this robust technology to attain extensive scopes in biomedical engineering platform. Various diagnostic techniques are used to analyze retinal microvasculature image to enable geometric features measurements such as vessel tortuosity, branching angles, branching coefficient, vessel diameter, and fractal dimension. These extracted markers or characterized fundus digital image features provide insights and relates quantitative retinal vascular topography abnormalities to various pathologies such as diabetic retinopathy, macular degeneration, hypertensive retinopathy, transient ischemic attack, neovascular glaucoma, and cardiovascular diseases. Apart from that, this noninvasive research tool is automated, allowing it to be used in large-scale screening programs, and all are described in this present review paper. This paper will also review recent research on the image processing-based extraction techniques of the quantitative retinal microvascular feature. It mainly focuses on features associated with the early symptom of transient ischemic attack or sharp stroke.
    Matched MeSH terms: Fundus Oculi
  18. Bakri NM, Ramachandran V, Kee HF, Subrayan V, Isa H, Ngah NF, et al.
    Kaohsiung J. Med. Sci., 2017 Dec;33(12):602-608.
    PMID: 29132549 DOI: 10.1016/j.kjms.2017.08.003
    Age-related macular degeneration (AMD) is the most widely recognised cause of irreversible vision loss and previous studies have suggested that the advancement of wet AMD is influenced by both modifiable and non-modifiable elements. Single nucleotide polymorphism (SNPs) and copy number of variations (CNVs) have been associated with AMD in various populations, however the results are conflicting. Our aim is to determine the CNVs of Complement Factor H-Related genes among Malaysian subjects with wet AMD. 130 patients with wet AMD and 120 healthy controls were included in this research. DNA was extracted from all subjects and CNVs of CFH, CFHR1 and CFHR3 genes; determined using quantitative real-time PCR and were compared between the two groups. A consistent association was observed between CFH gene and wet AMD susceptibility (P 
    Matched MeSH terms: Fundus Oculi
  19. Maheshwari S, Pachori RB, Kanhangad V, Bhandary SV, Acharya UR
    Comput Biol Med, 2017 Sep 01;88:142-149.
    PMID: 28728059 DOI: 10.1016/j.compbiomed.2017.06.017
    Glaucoma is one of the leading causes of permanent vision loss. It is an ocular disorder caused by increased fluid pressure within the eye. The clinical methods available for the diagnosis of glaucoma require skilled supervision. They are manual, time consuming, and out of reach of common people. Hence, there is a need for an automated glaucoma diagnosis system for mass screening. In this paper, we present a novel method for an automated diagnosis of glaucoma using digital fundus images. Variational mode decomposition (VMD) method is used in an iterative manner for image decomposition. Various features namely, Kapoor entropy, Renyi entropy, Yager entropy, and fractal dimensions are extracted from VMD components. ReliefF algorithm is used to select the discriminatory features and these features are then fed to the least squares support vector machine (LS-SVM) for classification. Our proposed method achieved classification accuracies of 95.19% and 94.79% using three-fold and ten-fold cross-validation strategies, respectively. This system can aid the ophthalmologists in confirming their manual reading of classes (glaucoma or normal) using fundus images.
    Matched MeSH terms: Fundus Oculi*
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