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1.
Invest Ophthalmol Vis Sci ; 60(4): 852-857, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30821810

RESUMEN

Purpose: To develop deep learning (DL) models for the automatic detection of optical coherence tomography (OCT) measures of diabetic macular thickening (MT) from color fundus photographs (CFPs). Methods: Retrospective analysis on 17,997 CFPs and their associated OCT measurements from the phase 3 RIDE/RISE diabetic macular edema (DME) studies. DL with transfer-learning cascade was applied on CFPs to predict time-domain OCT (TD-OCT)-equivalent measures of MT, including central subfield thickness (CST) and central foveal thickness (CFT). MT was defined by using two OCT cutoff points: 250 µm and 400 µm. A DL regression model was developed to directly quantify the actual CFT and CST from CFPs. Results: The best DL model was able to predict CST ≥ 250 µm and CFT ≥ 250 µm with an area under the curve (AUC) of 0.97 (95% confidence interval [CI], 0.89-1.00) and 0.91 (95% CI, 0.76-0.99), respectively. To predict CST ≥ 400 µm and CFT ≥ 400 µm, the best DL model had an AUC of 0.94 (95% CI, 0.82-1.00) and 0.96 (95% CI, 0.88-1.00), respectively. The best deep convolutional neural network regression model to quantify CST and CFT had an R2 of 0.74 (95% CI, 0.49-0.91) and 0.54 (95% CI, 0.20-0.87), respectively. The performance of the DL models declined when the CFPs were of poor quality or contained laser scars. Conclusions: DL is capable of predicting key quantitative TD-OCT measurements related to MT from CFPs. The DL models presented here could enhance the efficiency of DME diagnosis in tele-ophthalmology programs, promoting better visual outcomes. Future research is needed to validate DL algorithms for MT in the real-world.


Asunto(s)
Aprendizaje Profundo , Retinopatía Diabética/diagnóstico por imagen , Interpretación de Imagen Asistida por Computador/métodos , Mácula Lútea/patología , Edema Macular/diagnóstico por imagen , Fotograbar/métodos , Tomografía de Coherencia Óptica/métodos , Inhibidores de la Angiogénesis/uso terapéutico , Retinopatía Diabética/tratamiento farmacológico , Técnicas de Diagnóstico Oftalmológico , Reacciones Falso Positivas , Femenino , Fondo de Ojo , Humanos , Inyecciones Intravítreas , Edema Macular/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Redes Neurales de la Computación , Valor Predictivo de las Pruebas , Ensayos Clínicos Controlados Aleatorios como Asunto , Ranibizumab/uso terapéutico , Estudios Retrospectivos , Sensibilidad y Especificidad , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores
2.
Account Res ; 14(1): 1-18, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17847604

RESUMEN

Meta-analyses involve a systematic statistical explanation of available evidence and are a commonly used systematic reviewing strategy for addressing health related scientific research. Publication biases often delay reporting of meta-analyses and subsequent policy making. Ontologies have the capacity to provide real time meta-analyses that can reduce publication delay. The purpose of this study was to describe the meta-analytic process of a recently revised ontology. Three recently published meta-analyses were replicated using an ontology that extracts appropriate statistical "tags" from the originally reviewed published manuscripts. The ontology was able to closely represent the findings of the original meta-analysis including funnel, forest, and summary statistics. The use of an ontology could improve the speed in which meta-analytic publications occur as well as potentially standardizing the required elements within a randomized controlled trial. The findings in this study demonstrate similar ontological output as used in the Trial Bank Project with decreased time requirements of the manuscript author and the software programmers. The use of an ontology may improve the reporting of meta-analysis and, when combined with an open access website, should assist in timely policy-making decisions by healthcare providers.


Asunto(s)
Informática Médica , Metaanálisis como Asunto , Sesgo de Publicación , Corticoesteroides/uso terapéutico , Antirretrovirales/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/mortalidad , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto
3.
Arch Pathol Lab Med ; 130(3): 393-6, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16519572

RESUMEN

A 93-year-old woman developed a mass on her right lower eyelid that was present for more than 6 months but underwent rapid expansion during several weeks prior to her ophthalmological evaluation. Examination revealed an approximately 1.8 cm in diameter, fleshy, fungating growth involving more than 60% of the right lower eyelid. Excisional biopsy disclosed a neoplasm arising from the epidermis composed of adjoining basal cell and signet-ring squamous cell carcinoma, without a transition zone. The cells comprising the basal and squamous cell carcinomas were distinct immunophenotypically, with only the basal cell carcinoma reacting with Ber-EP4 and CAM 5.2 antibodies. To our knowledge, this case represents the first example of a collision tumor composed of basal cell and signet-ring squamous cell carcinoma.


Asunto(s)
Carcinoma Basocelular/patología , Carcinoma de Células en Anillo de Sello/patología , Carcinoma de Células Escamosas/patología , Neoplasias de los Párpados/patología , Anciano de 80 o más Años , Biomarcadores/análisis , Biomarcadores de Tumor/análisis , Carcinoma Basocelular/química , Carcinoma Basocelular/cirugía , Carcinoma de Células en Anillo de Sello/química , Carcinoma de Células en Anillo de Sello/cirugía , Carcinoma de Células Escamosas/química , Carcinoma de Células Escamosas/cirugía , Neoplasias de los Párpados/química , Neoplasias de los Párpados/cirugía , Femenino , Humanos , Queratinas/análisis , Neoplasias Primarias Múltiples , Resultado del Tratamiento
4.
Clin Exp Ophthalmol ; 32(3): 243-50, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15180834

RESUMEN

BACKGROUND: As part of a study of visual function among Hong Kong Chinese adults, their attitudes and perceptions related to visual loss were examined. These included fear of visual loss, negative functional impacts of visual loss, the relationship between ageing and visual loss and help-seeking behaviours related to visual loss. Demographic factors associated with these variables were also studied. METHODS: The study population were people aged 40 and above randomly selected from the Shatin district of Hong Kong. The participants underwent eye examinations that included visual acuity, intraocular pressure measurement, visual field, slit-lamp biomicroscopy and ophthalmoscopy. The primary cause of visual disability was recorded. The participants were also asked about their attitudes and perceptions regarding visual loss using a structured questionnaire. RESULTS: The prevalence of bilateral visual disability was 2.2% among adults aged 40 or above and 6.4% among adults aged 60 or above. Nearly 36% of the participants selected blindness as the most feared disabling medical condition, which was substantially higher than conditions such as dementia, loss of limbs, deafness or aphasia. Inability to take care of oneself (21.0%), inconvenience related to mobility (20.2%) and inability to work (14.8%) were the three most commonly mentioned 'worst impact' effects of visual loss. Fully 68% of the participants believed that loss of vision is related to ageing. A majority of participants would seek help and advice from family members in case of visual loss. CONCLUSIONS: Visual function is perceived to be very important by Hong Kong Chinese adults. The fear of visual loss is widespread and particularly affects self-care and functional abilities. Visual loss is commonly seen as related to ageing. Attitudes and perceptions in this population may be modified by educational and outreach efforts in order to take advantage of preventive measures.


Asunto(s)
Pueblo Asiatico/etnología , Actitud Frente a la Salud/etnología , Ceguera/psicología , Autoimagen , Baja Visión/psicología , Personas con Daño Visual/estadística & datos numéricos , Adulto , Anciano , Ceguera/etnología , Ceguera/etiología , Femenino , Hong Kong/epidemiología , Humanos , Presión Intraocular , Masculino , Persona de Mediana Edad , Prevalencia , Encuestas y Cuestionarios , Baja Visión/etnología , Baja Visión/etiología , Agudeza Visual
5.
Br J Ophthalmol ; 86(1): 12-7, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11801495

RESUMEN

BACKGROUND: Visual acuity, visual functioning, and vision related quality of life outcomes after cataract surgery were assessed in a population based study in a suburban area of Hong Kong. METHODS: A cluster sampling design was used to select apartment buildings within housing estates for enumeration. All enumerated residents 60 years of age or over were invited for an eye examination and visual acuity measurement at a site within each estate. Visual functioning (VF) and vision related quality of life (QOL) questionnaires were administered to interview subjects who had undergone cataract surgery and to unoperated people with presenting visual acuity less than 6/60 in either eye, and a sample of those with normal visual acuity. RESULTS: 36.6% of the 310 cataract operated individuals had presenting visual acuity 6/18 or better in both eyes, and 40.0% when measured by pinhole. 4.5% were blind, with presenting visual acuity less than 6/60 in both eyes. Of operated eyes, 59.6% presented with visual acuity 6/18 or better. 11.2% of the operated eyes were blind with vision less than 6/60. Visual acuity outcomes 6/18 or better were marginally associated with surgery in private versus public hospitals. Lens status (pseudophakic versus aphakic) and surgical period (within the most recent 3 years versus before) were not significantly related to vision outcomes. Mean VF and QOL scores decreased consistently with decreasing vision status. Spearman correlation with vision status was 0.420 for VF scores and 0.313 for QOL scores. Among VF/QOL subscales, correlation was strongest for visual perception (r = 0.447) among VF subscales and weakest for self care (r = 0.171) among QOL subscales. Regression adjusted VF and QOL total scores for cataract operated individuals were slightly lower than for those of visually comparable unoperated individuals (p<0.05). CONCLUSIONS: Cataract operations in Hong Kong did not consistently produce good presenting visual acuity outcomes, suggesting that postoperative monitoring would be useful to minimise visual impairment in this population. Although vision outcomes were consistently correlated with all VF/QOL subscale scores, there was a differential impact with VF subscales usually being affected more by reduced acuity than the more general QOL subscales.


Asunto(s)
Extracción de Catarata , Agudeza Visual/fisiología , Anciano , Afaquia Poscatarata/fisiopatología , Extracción de Catarata/estadística & datos numéricos , Estudios Transversales , Femenino , Glaucoma/fisiopatología , Hong Kong , Humanos , Degeneración Macular/fisiopatología , Masculino , Persona de Mediana Edad , Atrofia Óptica/fisiopatología , Calidad de Vida , Errores de Refracción/fisiopatología , Análisis de Regresión , Resultado del Tratamiento
6.
Br J Ophthalmol ; 86(2): 133-9, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11815334

RESUMEN

BACKGROUND: The prevalence of vision impairment, unilateral/bilateral blindness, and cataract surgery were estimated in a population based survey among the elderly in a suburban area of Hong Kong. METHODS: 15 public, private, and home ownership scheme housing estates in the Shatin area of Hong Kong were subjected to cluster sampling to randomly select a cross section of people 60 years of age or older. Visual acuity measurements and ocular examinations were conducted at a community site within each estate. The principal cause of reduced vision was identified for eyes with presenting visual acuity worse than 6/18. RESULTS: A total of 3441 subjects from an enumerated population of 4487 (76.7%) completed an eye examination. The prevalence of presenting visual acuity less than 6/18 in at least one eye was 41.3%; and 73.1% in those 80 years of age or older. Unilateral blindness (acuity <6/60) was found in 7.9% of subjects and bilateral blindness in 1.8%. Refractive error and cataract were, respectively, the main causes of vision impairment and blindness. Visual impairment with either eye <6/18 increased with advancing age and was more prevalent in males, the less educated, and those living in public housing estates. The prevalence of cataract surgery was 9.1% and was associated with advancing age and less education. CONCLUSIONS: Blindness and visual disability were common in this socioeconomically advanced population, with most of it easily remedied. Because of a rapidly ageing population, healthcare planners in Hong Kong must prepare for an increasing burden of visual disability and blindness.


Asunto(s)
Extracción de Catarata/estadística & datos numéricos , Trastornos de la Visión/epidemiología , Distribución por Edad , Anciano , Anciano de 80 o más Años , Ceguera/epidemiología , Ceguera/etiología , Estudios Transversales , Escolaridad , Encuestas Epidemiológicas , Hong Kong/epidemiología , Humanos , Persona de Mediana Edad , Prevalencia , Distribución por Sexo , Trastornos de la Visión/etiología
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