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1.
Sensors (Basel) ; 21(16)2021 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-34450766

RESUMEN

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.


Asunto(s)
Aprendizaje Profundo , Retinopatía Diabética , Inteligencia Artificial , Retinopatía Diabética/diagnóstico por imagen , Fondo de Ojo , Humanos , Redes Neurales de la Computación
2.
Sensors (Basel) ; 21(19)2021 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-34640698

RESUMEN

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.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Vasos Retinianos , Algoritmos , Técnicas de Diagnóstico Oftalmológico , Fondo de Ojo , Vasos Retinianos/diagnóstico por imagen
3.
Med J Malaysia ; 67(2): 159-64, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22822635

RESUMEN

Although few studies concerning optic neuritis (ON) in Asian countries have been reported, there is no report about ON in Malaysia particularly within the Malay population. We aimed to determine the clinical manifestation, visual outcome and aetiology of ON in Malays, and discussed the literature of ON studies in other Asian populations. This was a retrospective study involving 31 consecutive patients (41 eyes) with ON treated at Hospital Universiti Sains Malaysia commencing from July 2005 till January 2010 with a period of follow-up ranging from 18-60 months. The clinical features, laboratory results, possible aetiology, and visual acuity after one year were analysed. Females were the predominant group. The age of the patients ranged between 3-55 years and peaked between 21-30 years old. 67.7% of the patients had unilateral involvement. Pain on ocular movement was observed in 31.7% of the affected eyes. 73.3% of 41 involved eyes showed visual acuity equal 6/60 or worse on presentation. Paracentral scotoma was the most common visual field defect noted. Optic disc papillitis proved more widespread compared to the retrobulbar type of ON. The aetiology was idiopathic in more than 50%, while the risk of multiple sclerosis was extremely low (3.2%) in our series. 66.0% demonstrating visual acuity improved to 6/12 or better at one year after the attack. 16.1% showed evidence of recurrence during follow-up. In conclusion, the clinical profile and aetiology of ON in Malay patients are comparable to other ON studies reported by other Asian countries.


Asunto(s)
Neuritis Óptica/etiología , Adolescente , Adulto , Niño , Preescolar , Femenino , Hospitales de Enseñanza , Humanos , Malasia/epidemiología , Masculino , Persona de Mediana Edad , Neuritis Óptica/epidemiología , Estudios Retrospectivos
4.
Malays Fam Physician ; 17(1): 78-81, 2022 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-35440960

RESUMEN

A white-eyed blowout fracture is an orbital floor fracture associated with restriction of ocular motility (suggestive of orbital content entrapment) but with minimal or absence of signs of soft tissue trauma. It can lead to significant patient morbidity. This case involved an 8-year-old boy with a white-eyed blowout fracture following facial trauma. He presented with binocular diplopia and a history of recurrent episodes of vomiting after the trauma and was referred to our centre for a suspected head injury. Visual acuity in both eyes was 6/9. Examination showed minimal left periorbital haematoma with left eye motility restriction on superior and medial gaze associated with pain. CT scan of the orbit showed left orbital floor fracture with minimal soft tissue entrapment. He underwent urgent open exploration of the left orbit and release of orbital tissue entrapment. Post-operatively, the left eye motility restriction improved significantly with resolution of diplopia. In conclusion, a high index of suspicion is crucial in diagnosing paediatric white-eyed blowout fractures due to lack of external ocular signs.

5.
Front Neurosci ; 16: 833320, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35418832

RESUMEN

The debilitating effect of traumatic brain injury (TBI) extends years after the initial injury and hampers the recovery process and quality of life. In this study, we explore the functional reorganization of the default mode network (DMN) of those affected with non-severe TBI. Traumatic brain injury (TBI) is a wide-spectrum disease that has heterogeneous effects on its victims and impacts everyday functioning. The functional disruption of the default mode network (DMN) after TBI has been established, but its link to causal effective connectivity remains to be explored. This study investigated the differences in the DMN between healthy participants and mild and moderate TBI, in terms of functional and effective connectivity using resting-state functional magnetic resonance imaging (fMRI). Nineteen non-severe TBI (mean age 30.84 ± 14.56) and twenty-two healthy (HC; mean age 27.23 ± 6.32) participants were recruited for this study. Resting-state fMRI data were obtained at the subacute phase (mean days 40.63 ± 10.14) and analyzed for functional activation and connectivity, independent component analysis, and effective connectivity within and between the DMN. Neuropsychological tests were also performed to assess the cognitive and memory domains. Compared to the HC, the TBI group exhibited lower activation in the thalamus, as well as significant functional hypoconnectivity between DMN and LN. Within the DMN nodes, decreased activations were detected in the left inferior parietal lobule, precuneus, and right superior frontal gyrus. Altered effective connectivities were also observed in the TBI group and were linked to the diminished activation in the left parietal region and precuneus. With regard to intra-DMN connectivity within the TBI group, positive correlations were found in verbal and visual memory with the language network, while a negative correlation was found in the cognitive domain with the visual network. Our results suggested that aberrant activities and functional connectivities within the DMN and with other RSNs were accompanied by the altered effective connectivities in the TBI group. These alterations were associated with impaired cognitive and memory domains in the TBI group, in particular within the language domain. These findings may provide insight for future TBI observational and interventional research.

6.
Front Neurol ; 13: 1011304, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36303559

RESUMEN

Background: Impairment in cognitive function is a recognized outcome of traumatic brain injury (TBI). However, the degree of impairment has variable relationship with TBI severity and time post injury. The underlying pathology is often due to diffuse axonal injury that has been found even in mild TBI. In this study, we examine the state of white matter putative connectivity in patients with non-severe TBI in the subacute phase, i.e., within 10 weeks of injury and determine its relationship with neuropsychological scores. Methods: We conducted a case-control prospective study involving 11 male adult patients with non-severe TBI and an age-matched control group of 11 adult male volunteers. Diffusion MRI scanning and neuropsychological tests were administered within 10 weeks post injury. The difference in fractional anisotropy (FA) values between the patient and control groups was examined using tract-based spatial statistics. The FA values that were significantly different between patients and controls were then correlated with neuropsychological tests in the patient group. Results: Several clusters with peak voxels of significant FA reductions (p < 0.05) in the white matter skeleton were seen in patients compared to the control group. These clusters were located in the superior fronto-occipital fasciculus, superior longitudinal fasciculus, uncinate fasciculus, and cingulum, as well as white matter fibers in the area of genu of corpus callosum, anterior corona radiata, superior corona radiata, anterior thalamic radiation and part of inferior frontal gyrus. Mean global FA magnitude correlated significantly with MAVLT immediate recall scores while matrix reasoning scores correlated positively with FA values in the area of right superior fronto-occipital fasciculus and left anterior corona radiata. Conclusion: The non-severe TBI patients had abnormally reduced FA values in multiple regions compared to controls that correlated with several measures of executive function during the sub-acute phase of TBI.

7.
BMC Ophthalmol ; 10: 20, 2010 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-20738840

RESUMEN

BACKGROUND: Despite growing number of intraocular lens power calculation formulas, there is no evidence that these formulas have good predictive accuracy in pediatric, whose eyes are still undergoing rapid growth and refractive changes. This study is intended to compare the prediction error and the accuracy of predictability of intraocular lens power calculation in pediatric patients at 3 month post cataract surgery with primary implantation of an intraocular lens using SRK II versus Pediatric IOL Calculator for pediatric intraocular lens calculation. Pediatric IOL Calculator is a modification of SRK II using Holladay algorithm. This program attempts to predict the refraction of a pseudophakic child as he grows, using a Holladay algorithm model. This model is based on refraction measurements of pediatric aphakic eyes. Pediatric IOL Calculator uses computer software for intraocular lens calculation. METHODS: This comparative study consists of 31 eyes (24 patients) that successfully underwent cataract surgery and intraocular lens implantations. All patients were 12 years old and below (range: 4 months to 12 years old). Patients were randomized into 2 groups; SRK II group and Pediatric IOL Calculator group using envelope technique sampling procedure. Intraocular lens power calculations were made using either SRK II or Pediatric IOL Calculator for pediatric intraocular lens calculation based on the printed technique selected for every patient. Thirteen patients were assigned for SRK II group and another 11 patients for Pediatric IOL Calculator group. For SRK II group, the predicted postoperative refraction is based on the patient's axial length and is aimed for emmetropic at the time of surgery. However for Pediatric IOL Calculator group, the predicted postoperative refraction is aimed for emmetropic spherical equivalent at age 2 years old. The postoperative refractive outcome was taken as the spherical equivalent of the refraction at 3 month postoperative follow-up. The data were analysed to compare the mean prediction error and the accuracy of predictability of intraocular lens power calculation between SRK II and Pediatric IOL Calculator. RESULTS: There were 16 eyes in SRK II group and 15 eyes in Pediatric IOL Calculator group. The mean prediction error in the SRK II group was 1.03 D (SD, 0.69 D) while in Pediatric IOL Calculator group was 1.14 D (SD, 1.19 D). The SRK II group showed lower prediction error of 0.11 D compared to Pediatric IOL Calculator group, but this was not statistically significant (p = 0.74). There were 3 eyes (18.75%) in SRK II group achieved accurate predictability where the refraction postoperatively was within ± 0.5 D from predicted refraction compared to 7 eyes (46.67%) in the Pediatric IOL Calculator group. However the difference of the accuracy of predictability of postoperative refraction between the two formulas was also not statistically significant (p = 0.097). CONCLUSIONS: The prediction error and the accuracy of predictability of postoperative refraction in pediatric cataract surgery are comparable between SRK II and Pediatric IOL Calculator. The existence of the Pediatric IOL Calculator provides an alternative to the ophthalmologist for intraocular lens calculation in pediatric patients. Relatively small sample size and unequal distribution of patients especially the younger children (less than 3 years) with a short time follow-up (3 months), considering spherical equivalent only.


Asunto(s)
Extracción de Catarata , Lentes Intraoculares/normas , Refracción Ocular/fisiología , Algoritmos , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Reproducibilidad de los Resultados , Estudios Retrospectivos , Agudeza Visual
8.
J Pediatr Ophthalmol Strabismus ; 47(2): 111-3, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20349906

RESUMEN

The authors describe recurrent lens dislocation into the anterior chamber in a young girl with homocystinuria. The patient's 12-year-old sister died after a cerebrovascular accident caused by the same disease. This report highlights the importance of early dietary restrictions and treatment.


Asunto(s)
Subluxación del Cristalino/etiología , Cámara Anterior , Niño , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Homocistinuria/complicaciones , Humanos , Subluxación del Cristalino/diagnóstico , Subluxación del Cristalino/cirugía , Oftalmoscopía , Facoemulsificación/métodos , Agudeza Visual , Vitrectomía
9.
J Ophthalmic Vis Res ; 14(2): 171-178, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31114654

RESUMEN

PURPOSE: To determine the mutational analyses of familial exudative vitreoretinopathy (FEVR)-causing genes in Malay patients with retinopathy of prematurity (ROP) to obtain preliminary data for gene alterations in the Malay community. METHODS: A comparative cross-sectional study involving 86 Malay premature babies (ROP = 41 and non-ROP = 45) was performed from September 2012 to December 2014. Mutation analyses in (FEVR)-causing genes (NDP, FZD4, LRP5, and TSPAN12) were performed using DNA from premature babies using polymerase chain reaction (PCR) and direct sequencing. Sequencing results were confirmed with PCR-Restriction Fragment Length Polymorphism (RFLP). RESULTS: We found variants of FZD4, LRP5, and TSPAN12 in this study. One patient from each group showed a non-synonymous alteration in FZD4, c.502C>T (p.P168S). A synonymous variant of LRP5 [c.3357G>A (p.V1119V)] was found in 30 ROP and 28 non-ROP patients. Two variants of TSPAN12, c.765G>T (p.P255P) and c.*39C>T (3'UTR), were also recorded (29 and 21 in ROP, 33 and 26 in non-ROP, respectively). Gestational age and birth weight were found to be significantly associated with ROP (P value < 0.001 and 0.001, respectively). CONCLUSION: Analysis of data obtained from the ROP Malay population will enhance our understanding of these FEVR-causing gene variants. The c.3357G>A (p.V1119V) variant of LRP5, and c.765G>T (p.P255P) and c.*39C>T variants of TSPAN12 could be common polymorphisms in the Malay ethnic group; however, this requires further elucidation. Future studies using larger groups and higher numbers of advanced cases are necessary to evaluate the relationship between FEVR-causing gene variants and the risk of ROP susceptibility in Malaysian infants.

10.
BMC Ophthalmol ; 8: 7, 2008 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-18445283

RESUMEN

BACKGROUND: The sensitivity and specificity of 18S rRNA polymerase chain reaction (PCR) in the detection of fungal aetiology of microbial keratitis was determined in thirty patients with clinical diagnosis of microbial keratitis. METHODS: Corneal scrapings from patients were used for Gram stain, culture and PCR analysis. PCR was performed with primer pairs targeted to the 18S rRNA gene. The result of the PCR was compared with conventional culture and Gram staining method. The PCR positive samples were identified by DNA sequencing of the internal transcribed spacer (ITS) region of the rRNA gene. Main outcome measures were sensitivity and specificity of PCR in the detection of fungus in corneal keratitis. RESULTS: Combination of microscopy and culture gave a positive result in 11 of 30 samples of microbial keratitis. PCR detected 10 of 11 samples that were positive by conventional method. One of the 19 samples that was negative by conventional method was positive by PCR. Statistical analysis revealed that the PCR to have a sensitivity of 90.9% and specificity of 94.7% in the detection of a fungal aetiology in microbial keratitis. CONCLUSION: PCR is a rapid, sensitive and useful method to detect fungal aetiology in microbial keratitis.


Asunto(s)
Córnea/microbiología , Infecciones Fúngicas del Ojo/diagnóstico , Hongos/genética , Queratitis/microbiología , Reacción en Cadena de la Polimerasa/métodos , ARN Ribosómico 18S/aislamiento & purificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , ADN de Hongos , Femenino , Humanos , Queratitis/patología , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa/normas , Sensibilidad y Especificidad , Análisis de Secuencia , Factores de Tiempo
11.
Malays J Med Sci ; 14(2): 62-6, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22993494

RESUMEN

A 43 year-old man presented with pain on the right tooth for three days duration. Computed tomography showed left orbital cellulitis and right parapharyngeal abscess. There was also evidence suggestive of a dental abscess over right upper alveolar region. Magnetic resonance imaging revealed left superior ophthalmic vein thrombosis. Emergency drainage of the right parapharyngeal abscess was performed. Right maxillary molar extraction revealed periapical abscess. Left eye proptosis markedly reduced after initiating heparin.

12.
Malays J Med Sci ; 12(1): 64-7, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22605949

RESUMEN

A 40-year-old man presented with floaters and painless progressive blurring of vision in the right eye for one month duration. Visual acuity in the right eye was 6/24. There was mild anterior chamber reaction and vitritis. The optic disc was swollen and elevated with presence of granulomatous lesion in the optic disc head. Blood investigations were unremarkable. Serum angiotensin converting enzyme (ACE) was normal and conjunctival biopsy showed presence of inflammatory cells. B-Scan ultrasound revealed an echo-dense lesion in the optic nerve head. There was increased uptake of the right lacrimal gland and presence of 'Panda sign' with Gallium scan. A diagnosis of right ocular sarcoidosis was made base on the clinical features and Gallium scan.

13.
Clin Ophthalmol ; 7: 703-6, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23589678

RESUMEN

Herein, we report our experience in treating extensive traumatic submacular hemorrhage with a single dose of intravitreal ranibizumab. A 23-year-old healthy Malay man presented with a progressive reduction of central vision in the left eye of 2 days' duration following a history of blunt trauma. Visual acuity was reduced to counting fingers. Examination revealed infero-temporal subconjunctival hemorrhage, traumatic anterior uveitis, and an extensive sub-macular hemorrhage with suspicion of a choroidal rupture in the affected eye. He was initially treated conservatively with topical prednisolone acetate 1%. The subconjunctival hemorrhage and anterior uveitis resolved but his vision remained poor with minimal resolution of the submacular hemorrhage at 1 week follow-up (day 12 post-trauma). In view of the poor resolution of submacular hemorrhage, he was treated with a single dose of 0.5 mg intravitreal ranibizumab at day 20 post-trauma. At 4 weeks post-intravitreal ranibizumab, there was an improvement in visual acuity (from counting fingers to 6/45) and complete resolution of the submacular hemorrhage with presence of a choroidal rupture scar temporal to the fovea, which was not seen clearly at presentation due to obscuration by blood. His visual acuity further improved to 6/18 at 3 months post-trauma. Although this single case had a favorable outcome, a large population cohort study is needed to establish the effectiveness of intravitreal ranibizumab in treating extensive traumatic submacular hemorrhage.

14.
Int Med Case Rep J ; 5: 33-7, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23754920

RESUMEN

Here, a case of vision threatening blepharokeratoconjunctivitis that responded well to topical cyclosporin is reported. A 9-year-old Malay girl with a history of bilateral blepharokeratoconjunctivitis was regularly treated with lid scrubbing using diluted baby shampoo, fusidic acid gel, and topical steroids as well as an intermittent course of oral doxycycline for the past year. She developed acute onset bilateral eye redness associated with poor vision in her right eye. Both eyes showed marked diffuse hyperemic conjunctiva with corneal vascularization. The presence of corneal vascularization obscured the visual axis in the right eye. The condition did not improve with regular intensive lid hygiene using diluted baby shampoo, fusidic acid gel, and topical steroids. She was started on topical cyclosporin A 0.5% every 6 hours. There was a dramatic regression of corneal vascularization after 3 days on topical cyclosporin, with marked improvement in visual acuity. This is a single case in which cyclosporin improved the status of the ocular surface. A large cohort study is required to justify its effectiveness in treating blepharokeratoconjunctivitis and to test its potential as an alternative immunosuppressive agent in comparison to conventional corticosteroids.

15.
Int J Ophthalmol ; 4(1): 112-4, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22553623

RESUMEN

A 60 year-old man presented with acute on set of left eye proptosis and ptosis. It was associated with poor vision, eye pain and restriction of eye movement of the same eye after 5 hours post left upper molar tooth extraction. The visual acuity in the left eye was hand movement. There was severe ptosis and proptosis of the left eye. The conjunctiva was chemotic with quite anterior chamber. The pupil was mid dilated and sluggished to light. The ocular movement was restricted in all directions. Fundoscopy of the left eye revealed features of central retinal artery occlusion with hyperaemic disc and subretinal exudates at posterior pole. The right eye appeared normal. Urgent MRI brain and orbit revealed severe left paranasal sinusitis with anterior displacement of the left globe and presence orbital abscess. Patient was managed with Otorhinolaryngology and Neurosurgery teams. He underwent emergency transnasal drainage of abscess. Histopathological examination of unhealthy sinus mucosa showed evidence of fungal infection. However, the culture and sensitivity result was inconclusive. Patient was treated with amphotericin B, ceftriaxone, amoxicillin clavulanate and metronidazole. Patient was detected to have high blood sugar level and was managed accordingly. The proptosis improved with treatment. However, his vision, ptosis and ophthalmoplegia remained static. Assessing the immunocompromised status is important for the management of patient presented as acute orbital apex syndrome to avoid fatal outcome.

16.
Int J Ophthalmol ; 3(4): 361-4, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-22553594

RESUMEN

AIM: To evaluate the clinical manifestations and visual outcome of syphilitic uveitis patients. METHODS: Case series of three patients with syphilitic uveitis who were managed in Hospital USM. RESULTS: Three patients were diagnosed to have uveitis secondary to Syphilis. All three patients were not known to have syphilis prior to presentation but have positive history of sexual promiscuity. All patients presented with progressive blurring of vision for average of one-month duration. Two of them have association with fever, ocular pain and floaters. Visual acuity at presentation ranges from 6/12 to hand movement. Mild anterior uveitis (non-granulomatous), vitritis and papillitis were presence in all the patients. First patient has multifocal chorioretinitis with exudative retinal detachment. The second patient presented with exudative retinal detachment while the third patient has chorioretinitis only. All the patients were treated with intramuscular benzyl-penicillin 2.4 MU weekly for 4 weeks and two of them received oral doxycycline 200mg twice daily for 3 months. The uveitis responded well to the treatment and two of them showed dramatic visual improvement from 6/120 to 6/21 and 6/12 to 6/6. The one with worse outcome was confirmed to have positive retroviral. CONCLUSION: Ocular syphilis presented here as non-granulomatous inflammation associated with exudative retinal detachment. Final visual outcome is generally good despite slow improvement after treatment.

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