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Sample records for fundus albipunctatus asociado

  1. Genetics Home Reference: fundus albipunctatus

    Science.gov (United States)

    ... Lorenz B, Sander B, Larsen M, Eckstein C, Rosenberg T. Lack of autofluorescence in fundus albipunctatus associated ... Preising M, Lorenz B, Sander B, Larsen M, Rosenberg T. Fundus albipunctatus associated with compound heterozygous mutations ...

  2. Fundus albipunctatus associated with compound heterozygous mutations in RPE65

    DEFF Research Database (Denmark)

    Schatz, Patrik; Preising, Markus; Lorenz, Birgit

    2011-01-01

    To describe a family with an 18-year-old woman with fundus albipunctatus and compound heterozygous mutations in RPE65 whose unaffected parents and 1 female sibling harbored single heterozygous RPE65 mutations.......To describe a family with an 18-year-old woman with fundus albipunctatus and compound heterozygous mutations in RPE65 whose unaffected parents and 1 female sibling harbored single heterozygous RPE65 mutations....

  3. Smartphone Fundus Photography.

    Science.gov (United States)

    Nazari Khanamiri, Hossein; Nakatsuka, Austin; El-Annan, Jaafar

    2017-07-06

    Smartphone fundus photography is a simple technique to obtain ocular fundus pictures using a smartphone camera and a conventional handheld indirect ophthalmoscopy lens. This technique is indispensable when picture documentation of optic nerve, retina, and retinal vessels is necessary but a fundus camera is not available. The main advantage of this technique is the widespread availability of smartphones that allows documentation of macula and optic nerve changes in many settings that was not previously possible. Following the well-defined steps detailed here, such as proper alignment of the phone camera, handheld lens, and the patient's pupil, is the key for obtaining a clear retina picture with no interfering light reflections and aberrations. In this paper, the optical principles of indirect ophthalmoscopy and fundus photography will be reviewed first. Then, the step-by-step method to record a good quality retinal image using a smartphone will be explained.

  4. Hyperspectral fundus imager

    Science.gov (United States)

    Truitt, Paul W.; Soliz, Peter; Meigs, Andrew D.; Otten, Leonard John, III

    2000-11-01

    A Fourier Transform hyperspectral imager was integrated onto a standard clinical fundus camera, a Zeiss FF3, for the purposes of spectrally characterizing normal anatomical and pathological features in the human ocular fundus. To develop this instrument an existing FDA approved retinal camera was selected to avoid the difficulties of obtaining new FDA approval. Because of this, several unusual design constraints were imposed on the optical configuration. Techniques to calibrate the sensor and to define where the hyperspectral pushbroom stripe was located on the retina were developed, including the manufacturing of an artificial eye with calibration features suitable for a spectral imager. In this implementation the Fourier transform hyperspectral imager can collect over a hundred 86 cm-1 spectrally resolved bands with 12 micro meter/pixel spatial resolution within the 1050 nm to 450 nm band. This equates to 2 nm to 8 nm spectral resolution depending on the wavelength. For retinal observations the band of interest tends to lie between 475 nm and 790 nm. The instrument has been in use over the last year successfully collecting hyperspectral images of the optic disc, retinal vessels, choroidal vessels, retinal backgrounds, and macula diabetic macular edema, and lesions of age-related macular degeneration.

  5. [Fundus Autofluorescence Imaging].

    Science.gov (United States)

    Schmitz-Valckenberg, S

    2015-09-01

    Fundus autofluorescence (FAF) imaging allows for non-invasive mapping of changes at the level of the retinal pigment epithelium/photoreceptor complex and of alterations of macular pigment distribution. This imaging method is based on the visualisation of intrinsic fluorophores and may be easily and rapidly used in routine patient care. Main applications include degenerative disorders of the outer retina such as age-related macular degeneration, hereditary and acquired retinal diseases. FAF imaging is particularly helpful for differential diagnosis, detection and extent of involved retinal areas, structural-functional correlations and monitoring of changes over time. Recent developments include - in addition to the original application of short wavelength light for excitation ("blue" FAF imaging) - the use of other wavelength ranges ("green" or "near-infrared" FAF imaging), widefield imaging for visualisation of peripheral retinal areas and quantitative FAF imaging. Georg Thieme Verlag KG Stuttgart · New York.

  6. Fundus autofluorescence in serpiginouslike choroiditis.

    Science.gov (United States)

    Gupta, Amod; Bansal, Reema; Gupta, Vishali; Sharma, Aman

    2012-04-01

    To report the fundus autofluorescence characteristics in serpiginouslike choroiditis. Twenty-nine patients with presumed tubercular serpiginouslike choroiditis between November 2008 and January 2010 underwent fundus autofluorescence imaging during the acute stage and at regular intervals till the lesions healed. All patients received antitubercular therapy with oral corticosteroids. The autofluorescence images were compared with color fundus photography and fundus fluorescein angiography. The main outcome measure was fundus autofluorescence characteristics of lesions during the course of the disease. The pattern of fundus autofluorescence changed as the lesions evolved from the acute to the healed stage. In acute stage, the lesions showed an ill-defined halo of increased autofluorescence (hyperautofluorescence), giving it a diffuse, amorphous appearance (Stage I, acute). As the lesions began to heal, a thin rim of decreased autofluorescence (hypoautofluorescence) surrounded the lesion, defining its edges. The lesions showed predominantly hyperautofluorescence with stippled pattern (Stage II, subacute). With further healing, the hypoautofluorescence progressed and the lesion appeared predominantly hypoautofluorescent with stippled pattern (Stage III, nearly resolved). On complete healing, the lesions became uniformly hypoautofluorescent (Stage IV, completely resolved). Fundus autofluorescence highlighted the areas of disease activity and was a quick imaging tool for monitoring the course of lesions in serpiginouslike choroiditis.

  7. factores psicosociales asociados

    Directory of Open Access Journals (Sweden)

    María Teresa Varela Arévalo

    2007-01-01

    Full Text Available El objetivo de este trabajo fue describir el consumo de sustancias psicoactivas [SPA] ilegales en jóvenes y los factores psicosociales de riesgo y de protección asociados. Participaron 763 estudiantes (46,5% hombres y 52,4% mujeres de una universidad privada de Cali, quienes diligenciaron el cuestionario de factores de riesgo y protección para el consumo de drogas. Los resultados muestran que la marihuana fue la droga de mayor consumo; y que existe una fuerte asociación entre el consumo de las cuatro SPA ilegales (marihuana, opiáceos, cocaína y éxtasis y los factores psicosociales de riesgo y/o protección, principalmente, las habilidades de autocontrol, los preconceptos y valoración de las SPA, la relación con personas consumidoras y los comportamientos perturbadores.

  8. Ocular Fundus Photography as an Educational Tool.

    Science.gov (United States)

    Mackay, Devin D; Garza, Philip S

    2015-10-01

    The proficiency of nonophthalmologists with direct ophthalmoscopy is poor, which has prompted a search for alternative technologies to examine the ocular fundus. Although ocular fundus photography has existed for decades, its use has been traditionally restricted to ophthalmology clinical care settings and textbooks. Recent research has shown a role for nonmydriatic fundus photography in nonophthalmic settings, encouraging more widespread adoption of fundus photography technology. Recent studies have also affirmed the role of fundus photography as an adjunct or alternative to direct ophthalmoscopy in undergraduate medical education. In this review, the authors examine the use of ocular fundus photography as an educational tool and suggest future applications for this important technology. Novel applications of fundus photography as an educational tool have the potential to resurrect the dying art of funduscopy. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  9. Fundus Otoflöresans

    OpenAIRE

    ŞERMET, Figen

    2017-01-01

    Fundus otoflöresans görüntüleme, retina hastalıklarında patofizyolojik mekanizmaların anlaşılması, tanı, fenotipgenotipkorelasyonu, hastalık progresyonunu etkileyen faktörlerin belirlenmesi ve tedavi monitörizasyonunda yararlı birgörüntüleme yöntemidir. Fundus otoflöresans görüntüleme birçok hastalığın tanı ve takibinde kullanılabilir. Bu derlemedefundus otoflöresans görüntülemenin retina hastalıkları ve ayırıcı tanısında önemli rol oynadığı hastalıklar klinik olgufotoğraflarıyla da desteklen...

  10. Fundus autofluorescence: applications and perspectives.

    Science.gov (United States)

    Cuba, J; Gómez-Ulla, F

    2013-02-01

    To describe the findings of the study of autofluorescence of the different retinal diseases included in the study. To determine in which diseases autofluorescence may be more, or just as, useful as fluorescein angiography (FAG) in terms of diagnostic information. We studied the retinal autofluorescence of 123 eyes of 93 patients, including various diseases of the eye fundus. In all cases we explored the fundus, retinal autofluorescence, and, if indicated, FAG was performed. Analysis of the autofluorescence was performed using the Heidelberg Retina angiography Angiograph 2 (HRA2) Heidelberg Engineering (Germany). The autofluorescence information provided was equal or better (than FAG) in: 68.18% of cases of macular edema, 50% of pigment epithelium detachments, 100% of pigment epithelium atrophies, 100% of central serous chorioretinopathy; 55.55% of choroidal neovascularization, 100% of retinal dystrophies with deposition of lipofuscin, 100% of hard exudates and pre-retinal hemorrhages. Autofluorescence is a quick and non-invasive examination method, comfortable for both patient and examiner, and with a very short learning curve. It provides diagnostic information about many eye fundus diseases. While more studies and more experience with its use are needed, its interest lies in the possibility of avoiding the performing of angiography in patients with these diseases, and in the additional information autofluorescence provides about the functional situation of cells and retinal pigments. Copyright © 2011 Sociedad Española de Oftalmología. Published by Elsevier Espana. All rights reserved.

  11. Characterization of a dehydrogenase activity responsible for oxidation of 11-cis-retinol in the retinal pigment epithelium of mice with a disrupted RDH5 gene. A model for the human hereditary disease fundus albipunctatus.

    NARCIS (Netherlands)

    Jang, G.F.; Hooser, J.P. van; Kuksa, V.; McBee, J.K.; He, Y.G.; Janssen, J.J.M.; Driessen, C.A.G.G.; Palczewski, K.

    2001-01-01

    In the vertebrate retina, the final step of visual chromophore production is the oxidation of 11-cis-retinol to 11-cis-retinal. This reaction is catalyzed by 11-cis-retinol dehydrogenases (11-cis-RDHs), prior to the chromophore rejoining with the visual pigment apo-proteins. The RDH5 gene encodes a

  12. Coaxial fundus camera for opthalmology

    Science.gov (United States)

    de Matos, Luciana; Castro, Guilherme; Castro Neto, Jarbas C.

    2015-09-01

    A Fundus Camera for ophthalmology is a high definition device which needs to meet low light illumination of the human retina, high resolution in the retina and reflection free image1. Those constraints make its optical design very sophisticated, but the most difficult to comply with is the reflection free illumination and the final alignment due to the high number of non coaxial optical components in the system. Reflection of the illumination, both in the objective and at the cornea, mask image quality, and a poor alignment make the sophisticated optical design useless. In this work we developed a totally axial optical system for a non-midriatic Fundus Camera. The illumination is performed by a LED ring, coaxial with the optical system and composed of IR of visible LEDs. The illumination ring is projected by the objective lens in the cornea. The Objective, LED illuminator, CCD lens are coaxial making the final alignment easily to perform. The CCD + capture lens module is a CCTV camera with autofocus and Zoom built in, added to a 175 mm focal length doublet corrected for infinity, making the system easily operated and very compact.

  13. Fundus imaging with a nasal endoscope

    Directory of Open Access Journals (Sweden)

    P Mahesh Shanmugam

    2015-01-01

    Full Text Available Wide field fundus imaging is needed to diagnose, treat, and follow-up patients with retinal pathology. This is more applicable for pediatric patients as repeated evaluation is a challenge. The presently available imaging machines though provide high definition images, but carry the obvious disadvantages of either being costly or bulky or sometimes both, which limits its usage only to large centers. We hereby report a technique of fundus imaging using a nasal endoscope coupled with viscoelastic. A regular nasal endoscope with viscoelastic coupling was placed on the cornea to image the fundus of infants under general anesthesia. Wide angle fundus images of various fundus pathologies in infants could be obtained easily with readily available instruments and without the much financial investment for the institutes.

  14. Fundus Findings in Wernicke Encephalopathy

    Directory of Open Access Journals (Sweden)

    Tal Serlin

    2017-07-01

    Full Text Available Wernicke encephalopathy (WE is an acute neuropsychiatric syndrome resulting from thiamine (vitamin B1 deficiency, classically characterized by the triad of ophthalmoplegia, confusion, and ataxia. While commonly associated with chronic alcoholism, WE may also occur in the setting of poor nutrition or absorption. We present a 37-year-old woman who underwent laparoscopic sleeve gastrectomy and presented with visual disturbance with bilateral horizontal nystagmus, confusion, and postural imbalance. Fundus examination revealed bilateral optic disc edema with a retinal hemorrhage in the left eye. Metabolic workup demonstrated thiamine deficiency. Her symptoms resolved after thiamine treatment. This case raises the awareness of the possibility of posterior segment findings in WE, which are underreported in WE.

  15. Quantitative Fundus Autofluorescence in Recessive Stargardt Disease

    OpenAIRE

    Burke, Tomas R.; Duncker, Tobias; Woods, Russell L.; Greenberg, Jonathan P.; Zernant, Jana; Tsang, Stephen H.; Smith, R. Theodore; Allikmets, Rando; Sparrow, Janet R.; Delori, François C.

    2014-01-01

    Quantitative fundus autofluorescence (qAF) is significantly increased in Stargardt disease, consistent with previous reports of increased RPE lipofuscin. QAF will help to establish genotype-phenotype correlations and may serve as an outcome measure in clinical trials.

  16. An evaluation of fundus photography and fundus autofluorescence in the diagnosis of cuticular drusen

    DEFF Research Database (Denmark)

    Høeg, Tracy B; Moldow, Birgitte; Klein, Ronald

    2016-01-01

    PURPOSE: To examine non-mydriatic fundus photography (FP) and fundus autofluorescence (FAF) as alternative non-invasive imaging modalities to fluorescein angiography (FA) in the detection of cuticular drusen (CD). METHODS: Among 2953 adults from the Danish Rural Eye Study (DRES) with gradable FP...

  17. Quantitative fundus autofluorescence in recessive Stargardt disease.

    Science.gov (United States)

    Burke, Tomas R; Duncker, Tobias; Woods, Russell L; Greenberg, Jonathan P; Zernant, Jana; Tsang, Stephen H; Smith, R Theodore; Allikmets, Rando; Sparrow, Janet R; Delori, François C

    2014-05-01

    To quantify fundus autofluorescence (qAF) in patients with recessive Stargardt disease (STGD1). A total of 42 STGD1 patients (ages: 7-52 years) with at least one confirmed disease-associated ABCA4 mutation were studied. Fundus AF images (488-nm excitation) were acquired with a confocal scanning laser ophthalmoscope equipped with an internal fluorescent reference to account for variable laser power and detector sensitivity. The gray levels (GLs) of each image were calibrated to the reference, zero GL, magnification, and normative optical media density to yield qAF. Texture factor (TF) was calculated to characterize inhomogeneities in the AF image and patients were assigned to the phenotypes of Fishman I through III. Quantified fundus autofluorescence in 36 of 42 patients and TF in 27 of 42 patients were above normal limits for age. Young patients exhibited the relatively highest qAF, with levels up to 8-fold higher than healthy eyes. Quantified fundus autofluorescence and TF were higher in Fishman II and III than Fishman I, who had higher qAF and TF than healthy eyes. Patients carrying the G1916E mutation had lower qAF and TF than most other patients, even in the presence of a second allele associated with severe disease. Quantified fundus autofluorescence is an indirect approach to measuring RPE lipofuscin in vivo. We report that ABCA4 mutations cause significantly elevated qAF, consistent with previous reports indicating that increased RPE lipofuscin is a hallmark of STGD1. Even when qualitative differences in fundus AF images are not evident, qAF can elucidate phenotypic variation. Quantified fundus autofluorescence will serve to establish genotype-phenotype correlations and as an outcome measure in clinical trials.

  18. Quantitative Fundus Autofluorescence in Recessive Stargardt Disease

    Science.gov (United States)

    Burke, Tomas R.; Duncker, Tobias; Woods, Russell L.; Greenberg, Jonathan P.; Zernant, Jana; Tsang, Stephen H.; Smith, R. Theodore; Allikmets, Rando; Sparrow, Janet R.; Delori, François C.

    2014-01-01

    Purpose. To quantify fundus autofluorescence (qAF) in patients with recessive Stargardt disease (STGD1). Methods. A total of 42 STGD1 patients (ages: 7–52 years) with at least one confirmed disease-associated ABCA4 mutation were studied. Fundus AF images (488-nm excitation) were acquired with a confocal scanning laser ophthalmoscope equipped with an internal fluorescent reference to account for variable laser power and detector sensitivity. The gray levels (GLs) of each image were calibrated to the reference, zero GL, magnification, and normative optical media density to yield qAF. Texture factor (TF) was calculated to characterize inhomogeneities in the AF image and patients were assigned to the phenotypes of Fishman I through III. Results. Quantified fundus autofluorescence in 36 of 42 patients and TF in 27 of 42 patients were above normal limits for age. Young patients exhibited the relatively highest qAF, with levels up to 8-fold higher than healthy eyes. Quantified fundus autofluorescence and TF were higher in Fishman II and III than Fishman I, who had higher qAF and TF than healthy eyes. Patients carrying the G1916E mutation had lower qAF and TF than most other patients, even in the presence of a second allele associated with severe disease. Conclusions. Quantified fundus autofluorescence is an indirect approach to measuring RPE lipofuscin in vivo. We report that ABCA4 mutations cause significantly elevated qAF, consistent with previous reports indicating that increased RPE lipofuscin is a hallmark of STGD1. Even when qualitative differences in fundus AF images are not evident, qAF can elucidate phenotypic variation. Quantified fundus autofluorescence will serve to establish genotype-phenotype correlations and as an outcome measure in clinical trials. PMID:24677105

  19. Detection of Fundus Lesions Using Classifier Selection

    Science.gov (United States)

    Nagayoshi, Hiroto; Hiramatsu, Yoshitaka; Sako, Hiroshi; Himaga, Mitsutoshi; Kato, Satoshi

    A system for detecting fundus lesions caused by diabetic retinopathy from fundus images is being developed. The system can screen the images in advance in order to reduce the inspection workload on doctors. One of the difficulties that must be addressed in completing this system is how to remove false positives (which tend to arise near blood vessels) without decreasing the detection rate of lesions in other areas. To overcome this difficulty, we developed classifier selection according to the position of a candidate lesion, and we introduced new features that can distinguish true lesions from false positives. A system incorporating classifier selection and these new features was tested in experiments using 55 fundus images with some lesions and 223 images without lesions. The results of the experiments confirm the effectiveness of the proposed system, namely, degrees of sensitivity and specificity of 98% and 81%, respectively.

  20. Clinical significance of non-mydriatic fundus photography in screening for preschool children ocular fundus disease

    Directory of Open Access Journals (Sweden)

    Jun Luo

    2014-06-01

    Full Text Available AIM: To observe the incidence of ocular fundus disease in preschool children examined by non-mydriatic fundus camera and evaluate its effectiveness compared with direct inspection shadow mirror. METHODS: Three thousand eight hundred and ninety-six preschool children from April 2012 to October 2013 were examined by Topcon TRC-NW300 color fluorescence fundus camera and direct inspection shadow mirror, and images were saved immediately. RESULTS: Detection rate of non-mydriatic fundus photography was higher than that of direct inspection shadow mirror. In 3 896 cases, 41 eyes were detected abnormal fundus accounting for 1.05%. The retinal myelinated nerve fibers, morning glory syndrome, retinitis pigmentosa, congenital retinoschisis were common, accounted for 24.39%, 21.95%, 14.63%, 12.20% respectively. The children eye diseases were often accompanied by abnormal vision(68.30%, ametropia(63.41%, strabismus(19.51%.CONCLUSION: Non-mydriatic fundus photography is a mydriatic method without medicine, so it is easy for preschool children to accept. Image results could directly display the fundus lesions. It shows important significance in the screening for preschool children eye diseases.

  1. Fundus Autofluorescence Features of Optic Disc Pit Related ...

    African Journals Online (AJOL)

    chorioretinopathy, retina telangiectasia and diffuse and macula retina dystrophies.[1,3‑8] These features give useful clinical and prognostic information, making FAF a desired day‑to‑day clinical tool. Fundus autoflorescence signals can be detected using 3 different systems, the Delori's fundus. Fundus Autofluorescence ...

  2. 21 CFR 886.1395 - Diagnostic Hruby fundus lens.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Diagnostic Hruby fundus lens. 886.1395 Section 886...) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1395 Diagnostic Hruby fundus lens. (a) Identification. A diagnostic Hruby fundus lens is a device that is a 55 diopter lens intended for use in the...

  3. Fundus autofluorescence applications in retinal imaging

    Science.gov (United States)

    Gabai, Andrea; Veritti, Daniele; Lanzetta, Paolo

    2015-01-01

    Fundus autofluorescence (FAF) is a relatively new imaging technique that can be used to study retinal diseases. It provides information on retinal metabolism and health. Several different pathologies can be detected. Peculiar AF alterations can help the clinician to monitor disease progression and to better understand its pathogenesis. In the present article, we review FAF principles and clinical applications. PMID:26139802

  4. Analysis of visual pigment by fundus autofluorescence.

    NARCIS (Netherlands)

    Theelen, T.; Berendschot, T.T.; Boon, C.J.F.; Hoyng, C.B.; Klevering, B.J.

    2008-01-01

    This study investigated changes of short-wavelength fundus autofluorescence (SW-AF) by retinal bleaching effects. All measurements were performed with the Heidelberg Retina Angiograph 2 (HRA 2). Initially, experimental imaging was done on a healthy eye after dark adaptation. Photopigment was

  5. Fundus autofluorescence applications in retinal imaging

    Directory of Open Access Journals (Sweden)

    Andrea Gabai

    2015-01-01

    Full Text Available Fundus autofluorescence (FAF is a relatively new imaging technique that can be used to study retinal diseases. It provides information on retinal metabolism and health. Several different pathologies can be detected. Peculiar AF alterations can help the clinician to monitor disease progression and to better understand its pathogenesis. In the present article, we review FAF principles and clinical applications.

  6. Fundus reflectance : historical and present ideas

    NARCIS (Netherlands)

    Berendschot, T.T.J.M.; Delint, P.J.; Norren, D. van

    2003-01-01

    In 1851 Helmholtz introduced the ophthalmoscope. The instrument allowed the observation of light reflected at the fundus. The development of this device was one of the major advancements in ophthalmology. Yet ophthalmoscopy allows only qualitative observation of the eye. Since 1950 attempts were

  7. A study of fundus status in myopia

    Directory of Open Access Journals (Sweden)

    Christina Samuel, Sundararajan D

    2014-07-01

    Full Text Available Background: The most important sensory organ for a human is the eye. Any damage to the retina can cause diminution or loss of vision. One of the most important refractive errors of the eye is Myopia apart from hypermetropia and astigmatism. It is one of the commonest conditions seen in everyday practice. Myopic degeneration is one of the common causes of decreased visual acuity. Aim: The aim of this clinical study is to observe the fundus changes associated with Myopia. Methods: A prospective study of 100 cases of myopia were included in this study. Detailed anterior segment and good posterior segment examination after achieving mydriasis was done with a direct ophthalmoscope and indirect ophthalmoscope with 20D lens. Result: In our study, we found that males were more commonly affected than females with myopia (54%. 50% of the cases affected belonged to the student community. 53.68% had positive changes in the retina suggestive of degenerative changes in the fundus. Conclusion: Degenerative changes of fundus are most commonly seen in myopic patients of which Tessellated fundus was about 90.20%. Vitreous degenerative changes for 70.59%. Crescent formation was 87.25%. Dull foveal reflex in 82.35% and lattice degeneration accounted for 40%.

  8. A review of fundus autofluorescence imaging

    Directory of Open Access Journals (Sweden)

    D. J. Booysen

    2013-12-01

    Full Text Available Autofluorscence photography of the retina provides important diagnostic information about diseases that affect the outer retina; more specifically the retinal pigment epithelium and photoreceptors. Fundus autofluorescence can alsobe used to evaluate macular pigment density and other diseases of the retina and choroid. It is a non-invasive clinical tool which has the potential to revolutionise clinical retina practice. (S Afr Optom 2013 72(1 46-53

  9. A review of fundus autofluorescence imaging

    OpenAIRE

    D. J. Booysen

    2013-01-01

    Autofluorscence photography of the retina provides important diagnostic information about diseases that affect the outer retina; more specifically the retinal pigment epithelium and photoreceptors. Fundus autofluorescence can alsobe used to evaluate macular pigment density and other diseases of the retina and choroid. It is a non-invasive clinical tool which has the potential to revolutionise clinical retina practice. (S Afr Optom 2013 72(1) 46-53)

  10. Fundus autofluorescence and the bisretinoids of retina.

    Science.gov (United States)

    Sparrow, Janet R; Wu, Yalin; Nagasaki, Takayuki; Yoon, Kee Dong; Yamamoto, Kazunori; Zhou, Jilin

    2010-11-01

    Imaging of the human fundus of the eye with excitation wavelengths in the visible spectrum reveals a natural autofluorescence, that in a healthy retina originates primarily from the bisretinoids that constitute the lipofuscin of retinal pigment epithelial (RPE) cells. Since the intensity and distribution of fundus autofluorescence is altered in the presence of retinal disease, we have examined the fluorescence properties of the retinal bisretinoids with a view to aiding clinical interpretations. As is also observed for fundus autofluorescence, fluorescence emission from RPE lipofuscin was generated with a wide range of exciting wavelengths; with increasing excitation wavelength, the emission maximum shifted towards longer wavelengths and spectral width was decreased. These features are consistent with fluorescence generation from a mixture of compounds. While the bisretinoids that constitute RPE lipofuscin all fluoresced with maxima that were centered around 600 nm, fluorescence intensities varied when excited at 488 nm, the excitation wavelength utilized for fundus autofuorescence imaging. For instance the fluorescence efficiency of the bisretinoid A2-dihydropyridine-phosphatidylethanolamine (A2-DHP-PE) was greater than A2E and relative to both of the latter, all-trans-retinal dimer-phosphatidylethanolamine was weakly fluorescent. On the other hand, certain photooxidized forms of the bisretinoids present in both RPE and photoreceptor cells were more strongly fluorescent than the parent compound. We also sought to evaluate whether diffuse puncta of autofluorescence observed in some retinal disorders of monogenic origin are attributable to retinoid accumulation. However, two retinoids of the visual cycle, all-trans-retinyl ester and all-trans-retinal, did not exhibit fluorescence at 488 nm excitation.

  11. Do it yourself smartphone fundus camera – DIYretCAM

    Directory of Open Access Journals (Sweden)

    Biju Raju

    2016-01-01

    Full Text Available This article describes the method to make a do it yourself smartphone-based fundus camera which can image the central retina as well as the peripheral retina up to the pars plana. It is a cost-effective alternative to the fundus camera.

  12. FUNDUS AUTOFLUORESCENCE LIFETIMES AND CENTRAL SEROUS CHORIORETINOPATHY.

    Science.gov (United States)

    Dysli, Chantal; Berger, Lieselotte; Wolf, Sebastian; Zinkernagel, Martin S

    2017-11-01

    To quantify retinal fluorescence lifetimes in patients with central serous chorioretinopathy (CSC) and to identify disease specific lifetime characteristics over the course of disease. Forty-seven participants were included in this study. Patients with central serous chorioretinopathy were imaged with fundus photography, fundus autofluorescence, optical coherence tomography, and fluorescence lifetime imaging ophthalmoscopy (FLIO) and compared with age-matched controls. Retinal autofluorescence was excited using a 473-nm blue laser light and emitted fluorescence light was detected in 2 distinct wavelengths channels (498-560 nm and 560-720 nm). Clinical features, mean retinal autofluorescence lifetimes, autofluorescence intensity, and corresponding optical coherence tomography (OCT) images were further analyzed. Thirty-five central serous chorioretinopathy patients with a mean visual acuity of 78 ETDRS letters (range, 50-90; mean Snellen equivalent: 20/32) and 12 age-matched controls were included. In the acute stage of central serous chorioretinopathy, retinal fluorescence lifetimes were shortened by 15% and 17% in the respective wavelength channels. Multiple linear regression analysis showed that fluorescence lifetimes were significantly influenced by the disease duration (P autofluorescence lifetimes, particularly in eyes with retinal pigment epithelial atrophy, were associated with poor visual acuity. This study establishes that autofluorescence lifetime changes occurring in central serous chorioretinopathy exhibit explicit patterns which can be used to estimate perturbations of the outer retinal layers with a high degree of statistical significance.

  13. Fundus autofluorescence patterns in primary intraocular lymphoma.

    Science.gov (United States)

    Casady, Megan; Faia, Lisa; Nazemzadeh, Maryam; Nussenblatt, Robert; Chan, Chi-Chao; Sen, H Nida

    2014-02-01

    To evaluate fundus autofluorescence (FAF) patterns in patients with primary intraocular (vitreoretinal) lymphoma. Records of all patients with primary intraocular lymphoma who underwent FAF imaging at the National Eye Institute were reviewed. Fundus autofluorescence patterns were evaluated with respect to clinical disease status and the findings on fluorescein angiography and spectral-domain optical coherence tomography. There were 18 eyes (10 patients) with primary intraocular lymphoma that underwent FAF imaging. Abnormal autofluorescence in the form of granular hyperautofluorescence and hypoautofluorescence was seen in 11 eyes (61%), and blockage by mass lesion was seen in 2 eyes (11%). All eyes with granular pattern on FAF had active primary intraocular lymphoma at the time of imaging, but there were 5 eyes with unremarkable FAF, which were found to have active lymphoma. The most common pattern on fluorescein angiography was hypofluorescent round spots with a "leopard spot" appearance (43%). These hypofluorescent spots on fluorescein angiography correlated with hyperautofluorescent spots on FAF in 5 eyes (36%) (inversion of FAF). Nodular hyperreflective spots at the level of retinal pigment epithelium on optical coherence tomography were noted in 43% of eyes. The hyperautofluorescent spots on FAF correlated with nodular hyperreflective spots on optical coherence tomography in 6 eyes (43%). Granularity on FAF was associated with active lymphoma in majority of the cases. An inversion of FAF (hyperautofluorescent spots on FAF corresponding to hypofluorescent spots on fluorescein angiography) was observed in less than half of the eyes.

  14. Infrared-laser-based fundus angiography

    Science.gov (United States)

    Klingbeil, Ulrich; Canter, Joseph M.; Lesiecki, Michael L.; Reichel, Elias

    1994-06-01

    Infrared fundus angiography, using the fluorescent dye indocyanine green (ICG), has shown great potential in delineating choroidal neovascularization (CNV) otherwise not detectable. A digital retinal imaging system containing a diode laser for illumination has been developed and optimized to perform high sensitivity ICG angiography. The system requires less power and generates less pseudo-fluorescence background than nonlaser devices. During clinical evaluation at three retinal centers more than 200 patients, the majority of which had age-related macular degeneration, were analyzed. Laser based ICG angiography was successful in outlining many of the ill-defined or obscure CNV as defined by fluorescein angiography. The procedure was not as successful with classic CNV. ICG angiograms were used to prepare and guide laser treatment.

  15. Fundus autofluorescence and colour fundus imaging compared during telemedicine screening in patients with diabetes.

    Science.gov (United States)

    Kolomeyer, Anton M; Baumrind, Benjamin R; Szirth, Bernard C; Shahid, Khadija; Khouri, Albert S

    2013-06-01

    We investigated the use of fundus autofluorescence (FAF) imaging in screening the eyes of patients with diabetes. Images were obtained from 50 patients with type 2 diabetes undergoing telemedicine screening with colour fundus imaging. The colour and FAF images were obtained with a 15.1 megapixel non-mydriatic retinal camera. Colour and FAF images were compared for pathology seen in nonproliferative and proliferative diabetic retinopathy (NPDR and PDR, respectively). A qualitative assessment was made of the ease of detecting early retinopathy changes and the extent of existing retinopathy. The mean age of the patients was 47 years, most were male (82%) and most were African American (68%). Their mean visual acuity was 20/45 and their mean intraocular pressure was 14.3 mm Hg. Thirty-eight eyes (76%) did not show any diabetic retinopathy changes on colour or FAF imaging. Seven patients (14%) met the criteria for NPDR and five (10%) for severe NPDR or PDR. The most common findings were microaneurysms, hard exudates and intra-retinal haemorrhages (IRH) (n = 6 for each). IRH, microaneurysms and chorioretinal scars were more easily visible on FAF images. Hard exudates, pre-retinal haemorrhage and fibrosis, macular oedema and Hollenhorst plaque were easier to identify on colour photographs. The value of FAF imaging as a complementary technique to colour fundus imaging in detecting diabetic retinopathy during ocular screening warrants further investigation.

  16. Quantitative fundus autofluorescence in healthy eyes.

    Science.gov (United States)

    Greenberg, Jonathan P; Duncker, Tobias; Woods, Russell L; Smith, R Theodore; Sparrow, Janet R; Delori, François C

    2013-08-21

    Fundus autofluorescence was quantified (qAF) in subjects with healthy retinae using a standardized approach. The objective was to establish normative data and identify factors that influence the accumulation of RPE lipofuscin and/or modulate the observed AF signal in fundus images. AF images were acquired from 277 healthy subjects (age range: 5-60 years) by employing a Spectralis confocal scanning laser ophthalmoscope (cSLO; 488-nm excitation; 30°) equipped with an internal fluorescent reference. For each image, mean gray level was calculated as the average of eight preset regions, and was calibrated to the reference, zero-laser light, magnification, and optical media density from normative data on lens transmission spectra. Relationships between qAF and age, sex, race/ethnicity, eye color, refraction/axial length, and smoking status were evaluated as was measurement repeatability and the qAF spatial distribution. qAF levels exhibited a significant increase with age. qAF increased with increasing eccentricity up to 10° to 15° from the fovea and was highest superotemporally. qAF values were significantly greater in females, and, compared with Hispanics, qAF was significantly higher in whites and lower in blacks and Asians. No associations with axial length and smoking were observed. For two operators, between-session repeatability was ± 9% and ± 12%. Agreement between the operators was ± 13%. Normative qAF data are a reference tool essential to the interpretation of qAF measurements in ocular disease.

  17. Long-term fundus changes in acquired partial lipodystrophy.

    Science.gov (United States)

    Jansen, Joyce; Delaere, Lien; Spielberg, Leigh; Leys, Anita

    2013-11-18

    We describe long-term fundus changes in a patient with partial lipodystrophy (PL). Retinal pigment alterations, drusen and subretinal neovascularisation were seen without evidence for membranoproliferative glomerulonephritis. Fundus alterations similar to those seen in age-related macular degeneration can occur at an earlier age in patients with PL, even without renal disease. Dysregulation of an alternative complement pathway with low serum levels of C3 has been implicated as a pathogenetic mechanism.

  18. Analysis of phakic before intraocular lens implantation for fundus examination

    OpenAIRE

    Juan Chen; Zhong-Ping Chen; Rui-Ling Zhu

    2014-01-01

    AIM:To investigate the findings of the eyes which were examined preoperatively by three mirror contact lens before the implantation of implantable collamer lens(ICL). To analysis the retinal pathological changes and to explore the clinical analysis of early diagnosis and treatment in retinopathy on fundus examination before operation. METHODS:The retrospective case series study included 127 eyes of 64 patients who underwent phakic intraocular lens implantation were received the fundus examina...

  19. Inter-Rater Reliability of Cyclotorsion Measurements Using Fundus Photography.

    Science.gov (United States)

    Dysli, Muriel; Kanku, Madeleine; Traber, Ghislaine L

    2018-04-01

    The foveo-papillary angle (FPA) on fundus photographs is the accepted standard for the measurement of ocular cyclotorsion. We assessed the inter-rater reliability of this method in healthy subjects and in patients with trochlear nerve palsies. In this methodological study, fundus photographs of healthy subjects and of patients with trochlear nerve palsies were made with a fundus camera (Zeiss Fundus Camera FF 450 plus, Jena, Germany). Three independent observers measured the FPA on the fundus photographs of all subjects in synedra View (synedra View 16, Version 16.0.0.11, Innsbruck, Austria). One hundred and four eyes of 52 subjects (26 healthy controls and 26 patients) were assessed. The mean FPA of the healthy controls was 5.80 degrees (°) [± 0.44 standard error of the mean (SEM)] compared to 11.55° (± 0.80 SEM) for patients with trochlear nerve palsies. The inter-rater reliability of all measured FPAs showed an intraclass correlation coefficient (ICC) of 0.98 (95% CI 0.97 - 0.98). The inter-rater reliability of objective cyclotorsion measurements using fundus photographs was very high. Georg Thieme Verlag KG Stuttgart · New York.

  20. Retinal fundus imaging with a plenoptic sensor

    Science.gov (United States)

    Thurin, Brice; Bloch, Edward; Nousias, Sotiris; Ourselin, Sebastien; Keane, Pearse; Bergeles, Christos

    2018-02-01

    Vitreoretinal surgery is moving towards 3D visualization of the surgical field. This require acquisition system capable of recording such 3D information. We propose a proof of concept imaging system based on a light-field camera where an array of micro-lenses is placed in front of a conventional sensor. With a single snapshot, a stack of images focused at different depth are produced on the fly, which provides enhanced depth perception for the surgeon. Difficulty in depth localization of features and frequent focus-change during surgery are making current vitreoretinal heads-up surgical imaging systems cumbersome to use. To improve the depth perception and eliminate the need to manually refocus on the instruments during the surgery, we designed and implemented a proof-of-concept ophthalmoscope equipped with a commercial light-field camera. The sensor of our camera is composed of an array of micro-lenses which are projecting an array of overlapped micro-images. We show that with a single light-field snapshot we can digitally refocus between the retina and a tool located in front of the retina or display an extended depth-of-field image where everything is in focus. The design and system performances of the plenoptic fundus camera are detailed. We will conclude by showing in vivo data recorded with our device.

  1. Fundus autofluorescence in chronic essential hypertension.

    Science.gov (United States)

    Ramezani, Alireza; Saberian, Peyman; Soheilian, Masoud; Parsa, Saeed Alipour; Kamali, Homayoun Koohi; Entezari, Morteza; Shahbazi, Mohammad-Mehdi; Yaseri, Mehdi

    2014-01-01

    To evaluate fundus autofluorescence (FAF) changes in patients with chronic essential hypertension (HTN). In this case-control study, 35 eyes of 35 patients with chronic essential HTN (lasting >5 years) and 31 eyes of 31 volunteers without history of HTN were included. FAF pictures were taken from right eyes of all cases with the Heidelberg retina angiography and then were assessed by two masked retinal specialists. In total, FAF images including 35 images of hypertensive patients and 31 pictures of volunteers, three apparently abnormal patterns were detected. A ring of hyper-autofluorescence in the central macula (doughnut-shaped) was observed in 9 (25.7%) eyes of the hypertensive group but only in 2 (6.5%) eyes of the control group. This difference was statistically significant (P = 0.036) between two groups. Hypo- and/or hyper-autofluorescence patches outside the fovea were the other sign found more in the hypertensive group (22.9%) than in the control group (6.5%); however, the difference was not statistically significant (P = 0.089). The third feature was hypo-autofluorescence around the disk noticed in 11 (31.4%) eyes of hypertensive patients compared to 8 (25.8%) eyes of the controls (P = 0.615). A ring of hyper-autofluorescence in the central macula forming a doughnut-shaped feature may be a FAF sign in patients with chronic essential HTN.

  2. Fundus Autofluorescence in Chronic Essential Hypertension

    Directory of Open Access Journals (Sweden)

    Alireza Ramezani

    2014-01-01

    Full Text Available Purpose: To evaluate fundus autofluorescence (FAF changes in patients with chronic essential hypertension (HTN. Methods: In this case-control study, 35 eyes of 35 patients with chronic essential HTN (lasting >5 years and 31 eyes of 31 volunteers without history of HTN were included. FAF pictures were taken from right eyes of all cases with the Heidelberg retina angiography and then were assessed by two masked retinal specialists. Results: In total, FAF images including 35 images of hypertensive patients and 31 pictures of volunteers, three apparently abnormal patterns were detected. A ring of hyper-autofluorescence in the central macula (doughnut-shaped was observed in 9 (25.7% eyes of the hypertensive group but only in 2 (6.5% eyes of the control group. This difference was statistically significant (P = 0.036 between two groups. Hypo- and/or hyper-autofluorescence patches outside the fovea were the other sign found more in the hypertensive group (22.9% than in the control group (6.5%; however, the difference was not statistically significant (P = 0.089. The third feature was hypo-autofluorescence around the disk noticed in 11 (31.4% eyes of hypertensive patients compared to 8 (25.8% eyes of the controls (P = 0.615. Conclusion: A ring of hyper-autofluorescence in the central macula forming a doughnut-shaped feature may be a FAF sign in patients with chronic essential HTN.

  3. Fundus Autofluorescence and Photoreceptor Cell Rosettes in Mouse Models

    Science.gov (United States)

    Flynn, Erin; Ueda, Keiko; Auran, Emily; Sullivan, Jack M.; Sparrow, Janet R.

    2014-01-01

    Purpose. This study was conducted to study correlations among fundus autofluorescence (AF), RPE lipofuscin accumulation, and photoreceptor cell degeneration and to investigate the structural basis of fundus AF spots. Methods. Fundus AF images (55° lens; 488-nm excitation) and spectral-domain optical coherence tomography (SD-OCT) scans were acquired in pigmented Rdh8−/−/Abca4−/− mice (ages 1–9 months) with a confocal scanning laser ophthalmoscope (cSLO). For quantitative fundus AF (qAF), gray levels (GLs) were calibrated to an internal fluorescence reference. Retinal bisretinoids were measured by quantitative HPLC. Histometric analysis of outer nuclear layer (ONL) thicknesses was performed, and cryostat sections of retina were examined by fluorescence microscopy. Results. Quantified A2E and qAF intensities increased until age 4 months in the Rdh8−/−/Abca4−/− mice. The A2E levels declined after 4 months of age, but qAF intensity values continued to rise. The decline in A2E levels in the Rdh8−/−/Abca4−/− mice paralleled reduced photoreceptor cell viability as reflected in ONL thinning. Hyperautofluorescent puncta in fundus AF images corresponded to photoreceptor cell rosettes in SD-OCT images and histological sections stained with hematoxylin and eosin. The inner segment/outer segment–containing core of the rosette emitted an autofluorescence detected by fluorescence microscopy. Conclusions. When neural retina is disordered, AF from photoreceptor cells can contribute to noninvasive fundus AF images. Hyperautofluorescent puncta in fundus AF images are attributable, in at least some cases, to photoreceptor cell rosettes. PMID:25015357

  4. Fundus fluorescence Angiography in diagnosing diabetic retinopathy.

    Science.gov (United States)

    Wang, Shuhui; Zuo, Yuqin; Wang, Ning; Tong, Bin

    2017-01-01

    To investigate the manifestation characteristics of fundus fluorescence angiography (FFA) and its values in diagnosing diabetic retinopathy through comparing direct ophthalmoscopy. Two hundred fifty patients (500 eyes) who were suspected as diabetic retinopathy and admitted to the hospital between February 2015 and December 2016 were selected. They underwent direct ophthalmoscopy and FFA. The manifestation characteristics of FFA in the diagnosis of diabetic retinopathy were summarized. The two examination methods were compared. In the diagnosis with direct ophthalmoscopy, 375 eyes out of 500 eyes were diagnosed as diabetic retinopathy (75%); there were 74 eyes at stage I, 88 eyes at stage II, 92 eyes at stage III, 83 eyes of stage IV, 28 eyes of stage V and 10 eyes of stage VI. In the diagnosis with FFA, 465 eyes out of 500 eyes were diagnosed as diabetic retinopathy (93%); there were 94 eyes at stage I, 110 eyes at stage II, 112 at stage III, 92 eyes at stage IV, 41 eyes at stage V and 16 eyes at stage VI. The detection rate of diabetic retinopathy using FFA was significantly higher than that using direct ophthalmoscopy (Pretinopathy (67.96%), 75 eyes had pre-proliferative lesions (16.13%), 149 eyes had proliferative lesions (32.04%), 135 eyes had diabetic maculopathy (29.03%) and 31 eyes had diabetic optic disc lesions (6.67%). The detection rate of diabetic retinopathy using FFA is higher than that using direct ophthalmoscopy. FFA could accurately determine clinical stage. Therefore, it is an important approach in treatment efficacy evaluation and treatment guidance, suggesting a significant application value.

  5. Quantitative evaluation of papilledema from stereoscopic color fundus photographs.

    Science.gov (United States)

    Tang, Li; Kardon, Randy H; Wang, Jui-Kai; Garvin, Mona K; Lee, Kyungmoo; Abràmoff, Michael D

    2012-07-03

    To derive a computerized measurement of optic disc volume from digital stereoscopic fundus photographs for the purpose of diagnosing and managing papilledema. Twenty-nine pairs of stereoscopic fundus photographs and optic nerve head (ONH) centered spectral domain optical coherence tomography (SD-OCT) scans were obtained at the same visit in 15 patients with papilledema. Some patients were imaged at multiple visits in order to assess their changes. Three-dimensional shape of the ONH was estimated from stereo fundus photographs using an automated multi-scale stereo correspondence algorithm. We assessed the correlation of the stereo volume measurements with the SD-OCT volume measurements quantitatively, in terms of volume of retinal surface elevation above a reference plane and also to expert grading of papilledema from digital fundus photographs using the Frisén grading scale. The volumetric measurements of retinal surface elevation estimated from stereo fundus photographs and OCT scans were positively correlated (correlation coefficient r(2) = 0.60; P photographs compares favorably with that from OCT scans and with expert grading of papilledema severity. Stereoscopic color imaging of the ONH combined with a method of automated shape reconstruction is a low-cost alternative to SD-OCT scans that has potential for a more cost-effective diagnosis and management of papilledema in a telemedical setting. An automated three-dimensional image analysis method was validated that quantifies the retinal surface topography with an imaging modality that has lacked prior objective assessment.

  6. The Spectrum of Fundus Autofluorescence Findings in Birdshot Chorioretinopathy

    Directory of Open Access Journals (Sweden)

    GianPaolo Giuliari

    2009-01-01

    Full Text Available Objective. To describe the diverse patterns observed with the use of autofluorescence fundus photography (FAF in patients with Birdshot chorioretinopathy (BSCR. Methods. A chart review of patients with BSCR seen at the Massachusetts Eye Research and Surgery Institution, who had autofluorescence fundus photography. The data obtained included age, gender, presence of the HLA-A29 haplotype, and current treatment. Results. Eighteen eyes with HLA-A29 associated BSCR were included. Four eyes presented with active inflammation. Correspondence of the lesions noted in the colour fundus photograph was observed in 3 eyes which were more easily identified with the FAF. Fifteen eyes had fundus lesions more numerous and evident in the FAF than in the colour fundus photograph. Conclusion. Because FAF testing provides valuable insight into the metabolic state of the PR/RPE-complex, it may serve as a useful noninvasive assessment tool in patients with posterior uveitis in which the outer retina-RPE-choriocapillaries-complex is involved.

  7. Image analysis of ocular fundus for retinopathy characterization

    Energy Technology Data Exchange (ETDEWEB)

    Ushizima, Daniela; Cuadros, Jorge

    2010-02-05

    Automated analysis of ocular fundus images is a common procedure in countries as England, including both nonemergency examination and retinal screening of patients with diabetes mellitus. This involves digital image capture and transmission of the images to a digital reading center for evaluation and treatment referral. In collaboration with the Optometry Department, University of California, Berkeley, we have tested computer vision algorithms to segment vessels and lesions in ground-truth data (DRIVE database) and hundreds of images of non-macular centric and nonuniform illumination views of the eye fundus from EyePACS program. Methods under investigation involve mathematical morphology (Figure 1) for image enhancement and pattern matching. Recently, we have focused in more efficient techniques to model the ocular fundus vasculature (Figure 2), using deformable contours. Preliminary results show accurate segmentation of vessels and high level of true-positive microaneurysms.

  8. An evaluation of fundus photography and fundus autofluorescence in the diagnosis of cuticular drusen.

    Science.gov (United States)

    Høeg, Tracy B; Moldow, Birgitte; Klein, Ronald; La Cour, Morten; Klemp, Kristian; Erngaard, Ditte; Ellervik, Christina; Buch, Helena

    2016-03-01

    To examine non-mydriatic fundus photography (FP) and fundus autofluorescence (FAF) as alternative non-invasive imaging modalities to fluorescein angiography (FA) in the detection of cuticular drusen (CD). Among 2953 adults from the Danish Rural Eye Study (DRES) with gradable FP, three study groups were selected: (1) All those with suspected CD without age-related macular degeneration (AMD) on FP, (2) all those with suspected CD with AMD on FP and (3) a randomly selected group with early AMD. Groups 1, 2 and 3 underwent FA and FAF and group 4 underwent FAF only as part of DRES CD substudy. Main outcome measures included percentage of correct positive and correct negative diagnoses, Cohen's κ and prevalence-adjusted and bias-adjusted κ (PABAK) coefficients of test and grader reliability. CD was correctly identified on FP 88.9% of the time and correctly identified as not being present 83.3% of the time. CD was correctly identified on FAF 62.0% of the time and correctly identified as not being present 100.0% of the time. Compared with FA, FP has a PABAK of 0.75 (0.60 to 1.5) and FAF a PABAK of 0.44 (0.23 to 0.95). FP is a promising, non-invasive substitute for FA in the diagnosis of CD. FAF was less reliable than FP to detect CD. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  9. Fundus autofluorescence in retinal artery occlusion: A more precise diagnosis.

    Science.gov (United States)

    Bacquet, J-L; Sarov-Rivière, M; Denier, C; Querques, G; Riou, B; Bonin, L; Barreau, E; Labetoulle, M; Rousseau, A

    2017-10-01

    Retinal artery occlusion (RAO) is a medical emergency associated with a high risk of cerebral vascular accident and other cardiovascular events. Among patients with non-arteritic RAO, a retinal embolus is observed in approximately 40% of cases. Fundus examination and retinography are not reliable to predict the nature of the emboli. We report three consecutive cases of central and branch RAO that were investigated with fundus autofluorescence, fluorescein angiography and color retinal photographs. All patients underwent complete neurological and cardiovascular workups, with brain imaging, cardiac Doppler ultrasound, carotid Dopplers and Holter ECG's, to determine the underlying mechanism of retinal embolism. In the three cases, aged 77.7±4 years (2 women and 1 man), fundus autofluorescence demonstrated hyperautofluorescent emboli. In two cases, it allowed visualization of emboli that were not detected with fundus examination or retinography. The cardiovascular work-up demonstrated atheromatous carotid or aortic plaques in all patients. In one case, it permitted the diagnosis of RAO. Two of the three cases were considered to be of atherosclerotic origin and one of undefined origin. Fundus autofluorescence may help to detect and characterize retinal emboli. Since lipofuscin, which is present in large quantity in atherosclerotic plaques, is the main fluorophore detected with fundus autofluorescence, this non-invasive and simple examination may give information about the underlying mechanism of retinal embolism, and thus impact the etiologic assessment of RAO. Additional studies are necessary to confirm this potential role of autofluorescence. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  10. Personal identification based on blood vessels of retinal fundus images

    Science.gov (United States)

    Fukuta, Keisuke; Nakagawa, Toshiaki; Hayashi, Yoshinori; Hatanaka, Yuji; Hara, Takeshi; Fujita, Hiroshi

    2008-03-01

    Biometric technique has been implemented instead of conventional identification methods such as password in computer, automatic teller machine (ATM), and entrance and exit management system. We propose a personal identification (PI) system using color retinal fundus images which are unique to each individual. The proposed procedure for identification is based on comparison of an input fundus image with reference fundus images in the database. In the first step, registration between the input image and the reference image is performed. The step includes translational and rotational movement. The PI is based on the measure of similarity between blood vessel images generated from the input and reference images. The similarity measure is defined as the cross-correlation coefficient calculated from the pixel values. When the similarity is greater than a predetermined threshold, the input image is identified. This means both the input and the reference images are associated to the same person. Four hundred sixty-two fundus images including forty-one same-person's image pairs were used for the estimation of the proposed technique. The false rejection rate and the false acceptance rate were 9.9×10 -5% and 4.3×10 -5%, respectively. The results indicate that the proposed method has a higher performance than other biometrics except for DNA. To be used for practical application in the public, the device which can take retinal fundus images easily is needed. The proposed method is applied to not only the PI but also the system which warns about misfiling of fundus images in medical facilities.

  11. Krypton red laser photocoagulation of the ocular fundus. 1982.

    Science.gov (United States)

    Yannuzzi, Lawrence A; Shakin, Jeffrey L

    2012-02-01

    The theoretical rationale, the histopathologic evidence, and the preliminary clinical studies related to krypton red laser (KRL) photocoagulation of the ocular fundus are reviewed. The authors report on their experience with currently available laser systems using this wavelength (647.1 nm) for photocoagulation of retinal vascular proliferative diseases and chorioretinal diseases associated with exudative manifestations. A histopathologic and clinical comparison of argon blue-green laser (ABGL), the pure argon green laser (AGL), and the krypton yellow laser (KYL), with reference to photocoagulation treatment of the ocular fundus is also discussed.

  12. Fundus Findings in Dengue Fever: A Case Report

    Directory of Open Access Journals (Sweden)

    Berna Şahan

    2015-10-01

    Full Text Available Dengue fever is a flavivirus infection transmitted through infected mosquitoes, and is endemic in Southeast Asia, Central and South America, the Pacific, Africa and the Eastern Mediterranean region. A 41-year-old male patient had visual impairment after travelling to Thailand, which is one of the endemic areas. Cotton wool spots were observed on fundus examination. Fundus fluorescein angiography showed minimal vascular leakage from areas near the cotton wool spots and dot hemorrhages in the macula. Dengue fever should be considered in patients with visual complaints who traveled to endemic areas of dengue fever. (Turk J Ophthalmol 2015; 45: 223-225

  13. Aspectos biopsicosociales asociados al embarazo adolescente

    Directory of Open Access Journals (Sweden)

    Regina Cogollo Jiménez

    2012-12-01

    Full Text Available Introducción: El embarazo en la adolescencia, es un evento inesperado, sorpresivo. Este artículo establece la importancia de identificar los aspectos biopsicosociales asociados al embarazo adolescente en las embarazadas asistentes al programa de Control Prenatal de una Empresa Social del Estado de nivel 1 en Montería en 2009, para comprender las actitudes y los comportamientos asociados a esta etapa tan temprana. Materiales y Métodos: Es un estudio descriptivo, cuantitativo, de corte transversal. Población y muestra: 30 adolescentes embarazadas asistentes al Programa, el muestreo por conveniencia. Se utilizó la encuesta y la observación directa, previa autorización del Director de la empresa. Resultados: Caracterización de la población: predominó la edad de 15 a 19 años (adolescencia tardía, uniones libres, baja escolaridad debido a la deserción escolar, ingreso económico menor al salario mínimo legal vigente. Aspectos Biológicos: la menarquía a temprana edad (9 a 14 años, y en ella la mitad de los embarazos. La mayoría de los segundos embarazos terminaron en parto, la minoría en cesárea y aborto. La captación para los controles prenatales fue tardía, algunas no cumplieron con las citas programadas. Aspectos Psicológicos: inestabilidad con la pareja al enterarse del embarazo, tuvieron soporte familiar moral y económico, abandonaron sus estudios y presentaron malestares como estrés, depresión y tristeza. Aspectos Sociales: predominó la convivencia con la familia extensa. Hubo aceptación en el colegio y en los amigos. Discusión y Conclusiones: Se plantean estrategias para disminuir estos aspectos: elaboración de una cartilla sobre “Cuidado de la adolescente embarazada”, creación de espacios de reflexión, jornadas lúdicas educativas, entre otros. (Rev Cuid 2012; 3(3:385-93.Palabras clave: Embarazo en Adolescencia, Bienestar Materno, Atención Prenatal. (Fuente: De

  14. Determining degree of optic nerve edema from color fundus photography

    Science.gov (United States)

    Agne, Jason; Wang, Jui-Kai; Kardon, Randy H.; Garvin, Mona K.

    2015-03-01

    Swelling of the optic nerve head (ONH) is subjectively assessed by clinicians using the Frisén scale. It is believed that a direct measurement of the ONH volume would serve as a better representation of the swelling. However, a direct measurement requires optic nerve imaging with spectral domain optical coherence tomography (SD-OCT) and 3D segmentation of the resulting images, which is not always available during clinical evaluation. Furthermore, telemedical imaging of the eye at remote locations is more feasible with non-mydriatic fundus cameras which are less costly than OCT imagers. Therefore, there is a critical need to develop a more quantitative analysis of optic nerve swelling on a continuous scale, similar to SD-OCT. Here, we select features from more commonly available 2D fundus images and use them to predict ONH volume. Twenty-six features were extracted from each of 48 color fundus images. The features include attributes of the blood vessels, optic nerve head, and peripapillary retina areas. These features were used in a regression analysis to predict ONH volume, as computed by a segmentation of the SD-OCT image. The results of the regression analysis yielded a mean square error of 2.43 mm3 and a correlation coefficient between computed and predicted volumes of R = 0:771, which suggests that ONH volume may be predicted from fundus features alone.

  15. Ophthalmoscopy versus non-mydriatic fundus photography in the ...

    African Journals Online (AJOL)

    The contribution of non-mydriatic fundus photography in the detection of diabetic retinopathy before and after dilatation of the pupils in black diabetics was investigated and compared with direct ophthalmoscopy. Eighty-six patients were examined and good-quality photographs were obtained for 54,7% of eyes before and ...

  16. Fundus autofluorescence findings in a mouse model of retinal detachment.

    Science.gov (United States)

    Secondi, Roberta; Kong, Jian; Blonska, Anna M; Staurenghi, Giovanni; Sparrow, Janet R

    2012-08-07

    Fundus autofluorescence (fundus AF) changes were monitored in a mouse model of retinal detachment (RD). RD was induced by transscleral injection of hyaluronic acid (Healon) or sterile balanced salt solution (BSS) into the subretinal space of 4-5-day-old albino Abca4 null mutant and Abca4 wild-type mice. Images acquired by confocal scanning laser ophthalmoscopy (Spectralis HRA) were correlated with spectral domain optical coherence tomography (SD-OCT), infrared reflectance (IR), fluorescence spectroscopy, and histologic analysis. Results. In the area of detached retina, multiple hyperreflective spots in IR images corresponded to punctate areas of intense autofluorescence visible in fundus AF mode. The puncta exhibited changes in fluorescence intensity with time. SD-OCT disclosed undulations of the neural retina and hyperreflectivity of the photoreceptor layer that likely corresponded to histologically visible photoreceptor cell rosettes. Fluorescence emission spectra generated using flat-mounted retina, and 488 and 561 nm excitation, were similar to that of RPE lipofuscin. With increased excitation wavelength, the emission maximum shifted towards longer wavelengths, a characteristic typical of fundus autofluorescence. In detached retinas, hyper-autofluorescent spots appeared to originate from photoreceptor outer segments that were arranged within retinal folds and rosettes. Consistent with this interpretation is the finding that the autofluorescence was spectroscopically similar to the bisretinoids that constitute RPE lipofuscin. Under the conditions of a RD, abnormal autofluorescence may arise from excessive production of bisretinoid by impaired photoreceptor cells.

  17. Use of fundus autofluorescence images to predict geographic atrophy progression.

    Science.gov (United States)

    Bearelly, Srilaxmi; Khanifar, Aziz A; Lederer, David E; Lee, Jane J; Ghodasra, Jason H; Stinnett, Sandra S; Cousins, Scott W

    2011-01-01

    Fundus autofluorescence imaging has been shown to be helpful in predicting progression of geographic atrophy (GA) secondary to age-related macular degeneration. We assess the ability of fundus autofluorescence imaging to predict rate of GA progression using a simple categorical scheme. Subjects with GA secondary to age-related macular degeneration with fundus autofluorescence imaging acquired at least 12 months apart were included. Rim area focal hyperautofluorescence was defined as percentage of the 500-μm-wide margin bordering the GA that contained increased autofluorescence. Rim area focal hyperautofluorescence on baseline fundus autofluorescence images was assessed and categorized depending on the extent of rim area focal hyperautofluorescence (Category 1: ≤33%; Category 2: between 33 and 67%; Category 3: ≥67%). Total GA areas at baseline and follow-up were measured to calculate change in GA progression. Forty-five eyes of 45 subjects were included; average duration of follow-up was 18.5 months. Median growth rates differed among categories of baseline rim area focal hyperautofluorescence (P = 0.01 among Categories 1, 2, and 3; P = 0.008 for Category 1 compared with Category 3, Jonckheere-Terpstra test). A simple categorical scheme that stratifies the amount of increased autofluorescence in the 500-μm margin bordering GA may be used to differentiate faster and slower progressors.

  18. Automatic segmentation of blood vessels from retinal fundus images ...

    Indian Academy of Sciences (India)

    The retinal blood vessels were segmented through color space conversion and color channel .... Retinal blood vessel segmentation was also attempted through multi-scale operators. A few works in this ... fundus camera at 35 degrees field of view. The image ... vessel segmentation is available from two human observers.

  19. Ophthalmoscopy versus non-mydriatic fundus photography in the ...

    African Journals Online (AJOL)

    1990-09-01

    Sep 1, 1990 ... non-mydriatic fundus camera in the detection of diabetic retinopathy .... the external and the internal fixation lamps of the non- mydriatic ... .Rosen ES, Raines M, Hancock R. Use of non-mydriatic cameras to screen diabetic ...

  20. Non-mydriatic, wide field, fundus video camera

    Science.gov (United States)

    Hoeher, Bernhard; Voigtmann, Peter; Michelson, Georg; Schmauss, Bernhard

    2014-02-01

    We describe a method we call "stripe field imaging" that is capable of capturing wide field color fundus videos and images of the human eye at pupil sizes of 2mm. This means that it can be used with a non-dilated pupil even with bright ambient light. We realized a mobile demonstrator to prove the method and we could acquire color fundus videos of subjects successfully. We designed the demonstrator as a low-cost device consisting of mass market components to show that there is no major additional technical outlay to realize the improvements we propose. The technical core idea of our method is breaking the rotational symmetry in the optical design that is given in many conventional fundus cameras. By this measure we could extend the possible field of view (FOV) at a pupil size of 2mm from a circular field with 20° in diameter to a square field with 68° by 18° in size. We acquired a fundus video while the subject was slightly touching and releasing the lid. The resulting video showed changes at vessels in the region of the papilla and a change of the paleness of the papilla.

  1. Fundus autofluorescence features of optic disc pit related maculopathy

    African Journals Online (AJOL)

    Fundus autoflorescence (FAF) is a new investigational tool used to identify lipofuscin distribution in the retinal pigment epithelium (RPE) cell monolayer. It has recently been used to analyze age‑related macular degeneration, central serous chorioretinopathy, retina telangiectasia and diffuse and macula retina dystrophies.

  2. Textureless Macula Swelling Detection with Multiple Retinal Fundus Images

    Energy Technology Data Exchange (ETDEWEB)

    Giancardo, Luca [ORNL; Meriaudeau, Fabrice [ORNL; Karnowski, Thomas Paul [ORNL; Tobin Jr, Kenneth William [ORNL; Grisan, Enrico [University of Padua, Padua, Italy; Favaro, Paolo [Heriot-Watt University, Edinburgh; Ruggeri, Alfredo [University of Padua, Padua, Italy; Chaum, Edward [University of Tennessee, Knoxville (UTK)

    2010-01-01

    Retinal fundus images acquired with non-mydriatic digital fundus cameras are a versatile tool for the diagnosis of various retinal diseases. Because of the ease of use of newer camera models and their relatively low cost, these cameras can be employed by operators with limited training for telemedicine or Point-of-Care applications. We propose a novel technique that uses uncalibrated multiple-view fundus images to analyse the swelling of the macula. This innovation enables the detection and quantitative measurement of swollen areas by remote ophthalmologists. This capability is not available with a single image and prone to error with stereo fundus cameras. We also present automatic algorithms to measure features from the reconstructed image which are useful in Point-of-Care automated diagnosis of early macular edema, e.g., before the appearance of exudation. The technique presented is divided into three parts: first, a preprocessing technique simultaneously enhances the dark microstructures of the macula and equalises the image; second, all available views are registered using non-morphological sparse features; finally, a dense pyramidal optical flow is calculated for all the images and statistically combined to build a naiveheight- map of the macula. Results are presented on three sets of synthetic images and two sets of real world images. These preliminary tests show the ability to infer a minimum swelling of 300 microns and to correlate the reconstruction with the swollen location.

  3. Automatic Microaneurysm Detection and Characterization Through Digital Color Fundus Images

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Charles; Veras, Rodrigo; Ramalho, Geraldo; Medeiros, Fatima; Ushizima, Daniela

    2008-08-29

    Ocular fundus images can provide information about retinal, ophthalmic, and even systemic diseases such as diabetes. Microaneurysms (MAs) are the earliest sign of Diabetic Retinopathy, a frequently observed complication in both type 1 and type 2 diabetes. Robust detection of MAs in digital color fundus images is critical in the development of automated screening systems for this kind of disease. Automatic grading of these images is being considered by health boards so that the human grading task is reduced. In this paper we describe segmentation and the feature extraction methods for candidate MAs detection.We show that the candidate MAs detected with the methodology have been successfully classified by a MLP neural network (correct classification of 84percent).

  4. Clinical Investigation of Radiation Retinopathy Fundus and Fluorescein Angiographic Features

    Institute of Scientific and Technical Information of China (English)

    LiMei; QiuGT

    1999-01-01

    Purpose:To investigate the fundus and fluorescein angiographic features in the patients with radiation retinopathy.Clinical Materials:Color fundus photography and/or fluorescein angiography from 13 patients with nasopharyngeal carcinomas received external beam radiation were retrospectively analyzed.Reslts:In this study,26 damaged eyes of 13 patients eveloped some degree of radiation retinopathy.The earliest and most common finding was macular microvascular changes (microaneurysms and/or telangiectasia),which was observed in 100%(26/26)of the eyes.Intraretinal hemorrhages,macular capillary nonperfusion,and macular edema were noted in 84%,50%,and 42% of the eyes,respectively.Conclusions:Radiation retinopathy is common after external beam radiation of nasopharyngeal carcinomas.The prominent changes include maular microvascular changes,intraretinal hemorrhages and macular capillary nonperfusion.

  5. Automated detection of fundus photographic red lesions in diabetic retinopathy.

    Science.gov (United States)

    Larsen, Michael; Godt, Jannik; Larsen, Nicolai; Lund-Andersen, Henrik; Sjølie, Anne Katrin; Agardh, Elisabet; Kalm, Helle; Grunkin, Michael; Owens, David R

    2003-02-01

    To compare a fundus image-analysis algorithm for automated detection of hemorrhages and microaneurysms with visual detection of retinopathy in patients with diabetes. Four hundred fundus photographs (35-mm color transparencies) were obtained in 200 eyes of 100 patients with diabetes who were randomly selected from the Welsh Community Diabetic Retinopathy Study. A gold standard reference was defined by classifying each patient as having or not having diabetic retinopathy based on overall visual grading of the digitized transparencies. A single-lesion visual grading was made independently, comprising meticulous outlining of all single lesions in all photographs and used to develop the automated red lesion detection system. A comparison of visual and automated single-lesion detection in replicating the overall visual grading was then performed. Automated red lesion detection demonstrated a specificity of 71.4% and a resulting sensitivity of 96.7% in detecting diabetic retinopathy when applied at a tentative threshold setting for use in diabetic retinopathy screening. The accuracy of 79% could be raised to 85% by adjustment of a single user-supplied parameter determining the balance between the screening priorities, for which a considerable range of options was demonstrated by the receiver-operating characteristic (area under the curve 90.3%). The agreement of automated lesion detection with overall visual grading (0.659) was comparable to the mean agreement of six ophthalmologists (0.648). Detection of diabetic retinopathy by automated detection of single fundus lesions can be achieved with a performance comparable to that of experienced ophthalmologists. The results warrant further investigation of automated fundus image analysis as a tool for diabetic retinopathy screening.

  6. Interactive segmentation for geographic atrophy in retinal fundus images

    OpenAIRE

    Lee, Noah; Smith, R. Theodore; Laine, Andrew F.

    2008-01-01

    Fundus auto-fluorescence (FAF) imaging is a non-invasive technique for in vivo ophthalmoscopic inspection of age-related macular degeneration (AMD), the most common cause of blindness in developed countries. Geographic atrophy (GA) is an advanced form of AMD and accounts for 12–21% of severe visual loss in this disorder [3]. Automatic quantification of GA is important for determining disease progression and facilitating clinical diagnosis of AMD. The problem of automatic segmentation of patho...

  7. Case Report of Bullous Pemphigoid following Fundus Fluorescein Angiography

    Directory of Open Access Journals (Sweden)

    Goktug Demirci

    2010-05-01

    Full Text Available Purpose: To report a first case of bullous pemphigoid (BP following intravenous fluorescein for fundus angiography. Clinical Features: A 70-year-old male patient was admitted to the intensive care unit with BP and sepsis. He reported a history of fundus fluorescein angiography with a pre-diagnosis of senile macular degeneration 2 months prior to presentation. At that time, fluorescein extravasated at the antecubital region. Following the procedure, pruritus and erythema began at the wrists bilaterally, and quickly spread to the entire body. The patient also reported a history of allergy to human albumin solution (Plamasteril®; Abbott 15 years before, during bypass surgery. On dermatologic examination, erythematous patches were present on the scalp, chest and anogenital region. Vesicles and bullous lesions were present on upper and lower extremities. On day 2 of hospitalization, tense bullae appeared on the upper and lower extremities. The patient was treated with oral methylprednisolone 48 mg (Prednol®; Mustafa Nevzat, topical clobetasol dipropionate 0.05% cream (Dermovate®; Glaxo SmithKline, and topical 4% urea lotion (Excipial Lipo®; Orva for presumptive bullous pemphigoid. Skin punch biopsy provided tissue for histopathology, direct immunofluorescence examination, and salt extraction, which were all consistent with BP. After 1 month, the patient was transferred to the intensive care unit with sepsis secondary to urinary tract infection; he died 2 weeks later from sepsis and cardiac failure. Conclusions: To our knowledge, this is the first reported case of BP following fundus fluorescein angiography in a patient with known human albumin solution allergy. Consideration should be made to avoid fluorescein angiography, change administration route, or premedicate with antihistamines in patients with known human albumin solution allergy. The association between fundus fluorescein angiography and BP should be further investigated.

  8. Analysis of phakic before intraocular lens implantation for fundus examination

    Directory of Open Access Journals (Sweden)

    Juan Chen

    2014-10-01

    Full Text Available AIM:To investigate the findings of the eyes which were examined preoperatively by three mirror contact lens before the implantation of implantable collamer lens(ICL. To analysis the retinal pathological changes and to explore the clinical analysis of early diagnosis and treatment in retinopathy on fundus examination before operation. METHODS:The retrospective case series study included 127 eyes of 64 patients who underwent phakic intraocular lens implantation were received the fundus examination by three mirror from April 2011 to April 2012 in our hospital. The age, refractive diopter, the findings of Goldmann three mirror examination and the condition of retinal photocoagulation were analysed and concluded.RESULTS: A total of 34 eyes(26.8%out of all 127 eyes(64 caseswere found to have peripheral retinal pathological changes. Eight eyes(6.3%with retinal holes, 15 eyes(11.8%with retinal lattice degeneration, 5 eyes(3.9%with retina cream degeneration, 3 eyes(2.4%with retinal paving stone degeneration,2 eyes with vitreoretinal adhesion and traction,1 eye(0.8%with retinal hemorrhage. Twenty-five cases were given retinal photocoagulation and then received the ICL implantation after 3mo. The follow-up time was 1a. No retinal detachment happened.CONCLUSION:Phakic before intraocular lens implantation for fundus examination by three mirror is contributed to find the peripheral retinal pathological changes and abnormity. And make the appropriate treatment before operation for improving the security of operation, it can also give help to the postoperative follow-up of the fundus of these patients.

  9. Feasibility and quality of nonmydriatic fundus photography in children

    Science.gov (United States)

    Toffoli, Daniela; Bruce, Beau B.; Lamirel, Cédric; Henderson, Amanda D.; Newman, Nancy J.; Biousse, Valérie

    2011-01-01

    Purpose Ocular funduscopic examination is difficult in young children and is rarely attempted by nonophthalmologists. Our objective was to determine the feasibility of reliably obtaining high-quality nonmydriatic fundus photographs in children. Methods Nonmydriatic fundus photographs were obtained in both eyes of children seen in a pediatric ophthalmology clinic. Ease of fundus photography was recorded on a 10-point Likert scale (10 = very easy). Quality was graded from 1 to 5 (1, inadequate for any diagnostic purpose; 2, unable to exclude all emergent findings; 3, only able to exclude emergent findings; 4, not ideal, but still able to exclude subtle findings; and 5, ideal quality). The primary outcome measure was image quality by age. Results A total of 878 photographs of 212 children (median age, 6 years; range,1-18 years) were included. Photographs of at least one eye were obtained in 190 children (89.6%) and in both eyes in 181 (85.3%). Median rating for ease of photography was 7. Photographs of some clinical value (grade ≥2) were obtained in 33% of children 3 years. High-quality photographs (grade 4 or 5) were obtained in both eyes in 7% of children <3 years, 57% of children ≥3 to <7 years, 85% of children ≥7 to <9 years, and 65% of children ≥9 years. The youngest patient with high-quality photographs in both eyes was 22 months. Conclusions Nonmydriatic fundus photographs of adequate quality can be obtained in children over age 3 and in some children as young as 22 months. PMID:22153402

  10. The effects of fundus photography on the multifocal electroretinogram.

    Science.gov (United States)

    Suresh, Sandip; Tienor, Brian J; Smith, Scott D; Lee, Michael S

    2016-02-01

    To determine the effect of flash fundus photography (FFP) on the multifocal electroretinogram (mfERG). Ten subjects underwent mfERG testing on three separate dates. Subjects received either mfERG without FFP, mfERG at 5 and 15 min after FFP, or mfERG at 30 and 45 min after FFP on each date. The FFP groups received 10 fundus photographs followed by mfERG testing, first of the right eye then of the left eye 10 min later. Data were averaged and analyzed in six concentric rings at each time point. Average amplitude and implicit times of the N1, P1, and N2 peaks for each concentric ring at each time point after FFP were compared to baseline. Flash fundus photography did not lead to a significant change of amplitude or implicit times of N1, P1, or N2 at 5 min after light exposure. These findings suggest that it is acceptable to perform mfERG testing without delay after performance of FFP.

  11. Fundus autofluorescence imaging of the white dot syndromes.

    Science.gov (United States)

    Yeh, Steven; Forooghian, Farzin; Wong, Wai T; Faia, Lisa J; Cukras, Catherine; Lew, Julie C; Wroblewski, Keith; Weichel, Eric D; Meyerle, Catherine B; Sen, Hatice Nida; Chew, Emily Y; Nussenblatt, Robert B

    2010-01-01

    To characterize the fundus autofluorescence (FAF) findings in patients with white dot syndromes (WDSs). Patients with WDSs underwent ophthalmic examination, fundus photography, fluorescein angiography, and FAF imaging. Patients were categorized as having no, minimal, or predominant foveal hypoautofluorescence. The severity of visual impairment was then correlated with the degree of foveal hypoautofluorescence. Fifty-five eyes of 28 patients with WDSs were evaluated. Visual acuities ranged from 20/12.5 to hand motions. Diagnoses included serpiginous choroidopathy (5 patients), birdshot retinochoroidopathy (10), multifocal choroiditis (8), relentless placoid chorioretinitis (1), presumed tuberculosis-associated serpiginouslike choroidopathy (1), acute posterior multifocal placoid pigment epitheliopathy (1), and acute zonal occult outer retinopathy (2). In active serpiginous choroidopathy, notable hyperautofluorescence in active disease distinguished it from the variegated FAF features of tuberculosis-associated serpiginouslike choroidopathy. The percentage of patients with visual acuity impairment of less than 20/40 differed among eyes with no, minimal, and predominant foveal hypoautofluorescence (P < .001). Patients with predominant foveal hypoautofluorescence demonstrated worse visual acuity than those with minimal or no foveal hypoautofluorescence (both P < .001). Fundus autofluorescence imaging is useful in the evaluation of the WDS. Visual acuity impairment is correlated with foveal hypoautofluorescence. Further studies are needed to evaluate the precise role of FAF imaging in the WDSs.

  12. Brote de legionelosis asociado a un balneario

    Directory of Open Access Journals (Sweden)

    I. Santa Marina Rodríguez

    2001-06-01

    Full Text Available En 1998 el inicio de la temporada de actividad de un balneario en Gipuzkoa coincidió con la detección de un brote de legionelosis asociado al mismo, lo cual condujo al cierre de la instalación y al estudio epidemiológico -casos y controles- y ambiental oportunos. Se definió como caso toda persona que durante su estancia en el balneario o durante los 10 días siguientes presentará neumonía o un cuadro febril compatible con fiebre de Pontiac.El estudio ambiental incluyó la inspección del balneario y entorno y muestreos de los sistemas sanitarios de agua y de los elementos de hidroterapia.De las 287 personas encuestadas de la Comunidad Autónoma Vasca, el 12.5% cumplían con la definición de caso; 9 casos presentaron neumonía y 26 fiebre de Pontiac. La curva epidémica se inició el 7 de mayo, alcanzando un pico los días 14 y 15 de mayo y finalizando el día 20. El riesgo de enfermar ajustado por edad, sexo y consumo de tabaco se asoció con la duración de la estancia en el balneario (OR=118.5, 95% I.C: 18.7-750.2 y con el uso de una piscina (OR=10.5, 95% I.C: 1.3-82.6. Se detecto L. pneumophila serogrupo1 en recuentos superiores a 103 ufc/l en diversos puntos de la red de hidroterapia y en la ducha de la habitación de uno de los enfermos. El análisis por electroforesis en campos pulsados de una muestra biológica y muestras ambientales permitió la confirmación genotípica. El establecimiento se abrió al público tras realizar un tratamiento de choque y comprobar que transcurridos 15 días no se detectó L. pneumophila en las muestras ambientales.

  13. Cambios fisiológicos asociados al envejecimiento

    OpenAIRE

    Dr. M. Felipe Salech; Dr. L. Rafael Jara; A. Luis Michea, DR, PHD

    2012-01-01

    La población envejece en forma acelerada, y la comprensión de los cambios fisiológicos asociados al envejecimiento es una herramienta importante para enfrentar las demandas biomédicas y sociales de ese grupo etario. El objetivo de la presente revisión es definir los principales cambios morfológicos y funcionales en los sistemas cardiovascular, renal, nervioso central, muscular y metabolismo de la glucosa asociados a la edad. La evidencia de estudios clínicos y experimentales muestra que...

  14. Effect of isoproterenol, phenylephrine, and sodium nitroprusside on fundus pulsations in healthy volunteers.

    Science.gov (United States)

    Schmetterer, L; Wolzt, M; Salomon, A; Rheinberger, A; Unfried, C; Zanaschka, G; Fercher, A F

    1996-03-01

    Recently a laser interferometric method for topical measurement of fundus pulsations has been developed. Fundus pulsations in the macular region are caused by the inflow and outflow of blood into the choroid. The purpose of this work was to study the influence of a peripheral vasoconstricting (the alpha 1 adrenoceptor agonist phenylephrine), a predominantly positive inotropic (the non-specific beta adrenoceptor agonist isoproterenol), and a non-specific vasodilating (sodium nitroprusside) model drug on ocular fundus pulsations to determine reproducibility and sensitivity of the method. In a double masked randomised crossover study the drugs were administered in stepwise increasing doses to 10 male and nine female healthy volunteers. Systemic haemodynamic variables and fundus pulsations were measured at all infusion steps. Fundus pulsation increased during infusion of isoproterenol with statistical significance versus baseline at the lowest dose of 0.1 microgram/min. Neither peripheral vasoconstriction nor peripheral vasodilatation affected the ocular fundus pulsations. Measurements of fundus pulsations is a highly reproducible method in healthy subjects with low ametropy. Changes of local pulsatile ocular blood flow were detectable with our method following the infusion of isoproterenol. As systemic pharmacological vasodilatation or vasoconstriction did not change fundus pulsations, further experimental work has to be done to evaluate the sensitivity of the laser interferometric fundus pulsation measurement in various eye diseases.

  15. Cambios fisiológicos asociados al envejecimiento

    Directory of Open Access Journals (Sweden)

    Dr. M. Felipe Salech

    2012-01-01

    La evidencia disponible muestra importantes cambios morfológicos y funcionales asociados a la edad. El conocimiento de la población en edad media de la vida no debiera generalizarse a los adultos mayores. El reconocimiento de cambios debidos al envejecimiento normal es difícil por la gran variabilidad entre sujetos y la alta prevalencia de comorbilidad.

  16. [Fundus autofluorescence in dry AMD - impact on disease progression].

    Science.gov (United States)

    Vidinova, C N; Gouguchkova, P T; Vidinov, K N

    2013-11-01

    Fundus autofluorescence is a novel technique that gives us information about the RPE cells by evaluating the distribution of lipofuscin in the retina. The purpose of our study was to evaluate the diagnostic abilities of OCT, RTVue and fundus autofluorescence in predicting the progression of dry AMD. In our study 37 dry AMD patients were enrolled: 22 of them with druses and 15 with developed geographic atrophy. They all underwent complete ophthalmological examinations including OCT and autofluorescence. We used the RTVue OCT programmes HD line, Cross line, EMM5 and EMM5 progression in all cases. The autofluorescence was recorded with the help of the Canon CX1 fundus camera. OCT images in the AMD patients with dry AMD and large druses showed typical undulations in the RPE/choroid line and occasionally drusenoid detachment of the RPE. Autofluorescence showed different patterns. The confluent reticular autofluorescence was associated with the development of neovascular membranes. In geographic atrophy patient OCTs showed diminished retinal thickness measured with EMM5. On autofluorescence the findings at the border zone atrophic/normal retina were of particular importance. The diffuse increased autofluorescence in that area was considered to be a sign for further atrophy progression. Our results point out that OCT in combination with autofluorescence is important in following the progression of dry AMD. Pathological autofluorescence at the border of atrophic lesions is an important sign for disease activity. Although both OCT and autofluorescence visualise the changes in RPE, autofluorescence is of key importance in predicting the development of the disease. Georg Thieme Verlag KG Stuttgart · New York.

  17. Semi-automated retinal vessel analysis in nonmydriatic fundus photography.

    Science.gov (United States)

    Schuster, Alexander Karl-Georg; Fischer, Joachim Ernst; Vossmerbaeumer, Urs

    2014-02-01

    Funduscopic assessment of the retinal vessels may be used to assess the health status of microcirculation and as a component in the evaluation of cardiovascular risk factors. Typically, the evaluation is restricted to morphological appreciation without strict quantification. Our purpose was to develop and validate a software tool for semi-automated quantitative analysis of retinal vasculature in nonmydriatic fundus photography. matlab software was used to develop a semi-automated image recognition and analysis tool for the determination of the arterial-venous (A/V) ratio in the central vessel equivalent on 45° digital fundus photographs. Validity and reproducibility of the results were ascertained using nonmydriatic photographs of 50 eyes from 25 subjects recorded from a 3DOCT device (Topcon Corp.). Two hundred and thirty-three eyes of 121 healthy subjects were evaluated to define normative values. A software tool was developed using image thresholds for vessel recognition and vessel width calculation in a semi-automated three-step procedure: vessel recognition on the photograph and artery/vein designation, width measurement and calculation of central retinal vessel equivalents. Mean vessel recognition rate was 78%, vessel class designation rate 75% and reproducibility between 0.78 and 0.91. Mean A/V ratio was 0.84. Application on a healthy norm cohort showed high congruence with prior published manual methods. Processing time per image was one minute. Quantitative geometrical assessment of the retinal vasculature may be performed in a semi-automated manner using dedicated software tools. Yielding reproducible numerical data within a short time leap, this may contribute additional value to mere morphological estimates in the clinical evaluation of fundus photographs. © 2013 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  18. [Cinematography of ocular fundus with a jointed optical system and tv or cine-camera (author's transl)].

    Science.gov (United States)

    Kampik, A; Rapp, J

    1979-02-01

    A method of Cinematography of the ocular fundus is introduced which--by connecting a camera with an indirect ophthalmoscop--allows to record the monocular picture of the fundus as produced by the ophthalmic lens.

  19. Nonmydriatic Ocular Fundus Photography in the Emergency Department: How It Can Benefit Neurologists.

    Science.gov (United States)

    Bruce, Beau B

    2015-10-01

    Examination of the ocular fundus is a critical aspect of the neurologic examination. For example, in patients with headache the ocular fundus examination is needed to uncover "red flags" suggestive of secondary etiologies. However, ocular fundus examination is infrequently and poorly performed in clinical practice. Nonmydriatic ocular fundus photography provides an alternative to direct ophthalmoscopy that has been studied as part of the Fundus Photography versus Ophthalmoscopy Trial Outcomes in the Emergency Department (FOTO-ED) Study. Herein, the results of the FOTO-ED study are reviewed with a particular focus on the study's implications for the acute care of patients presenting with headache and focal neurologic deficits. In headache patients, not only optic disc edema and optic disc pallor were observed as would be expected, but also a large number of abnormalities associated with hypertension. Based upon subjects with focal neurologic deficits, the FOTO-ED study suggests that the ocular fundus examination may assist with the triage of patients presenting with suspected transient ischemic attack. Continued advances in the ease and portability of nonmydriatic fundus photography will hopefully help to restore ocular fundus examination as a routinely performed component of all neurologic examinations. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  20. Non-mydriatic ocular fundus photography in the emergency department: how it can benefit neurologists

    Science.gov (United States)

    Bruce, Beau B.

    2016-01-01

    Examination of the ocular fundus is a critical aspect of the neurological examination. For example, in patients with headache the ocular fundus examination is needed to uncover “red flags” suggestive of secondary etiologies. However, ocular fundus examination is infrequently and poorly performed in clinical practice. Non-mydriatic ocular fundus photography provides an alternative to direct ophthalmoscopy that has been studied as part of the Fundus photography vs. Ophthalmoscopy Trial Outcomes in the Emergency Department (FOTO-ED) study. Herein, we review the results of the FOTO-ED study with a particular focus on the study's implications for the acute care of patients presenting with headache and focal neurologic deficits. In headache patients, we not only observed optic disc edema and optic disc pallor as would be expected, but also a large number of abnormalities associated with hypertension. Based upon subjects with focal neurological deficits, the FOTO-ED study suggests that the ocular fundus examination may assist with the triage of patients presenting with suspected transient ischemic attack. Continued advances in the ease and portability of non-mydriatic fundus photography will hopefully help to restore ocular fundus examination as a routinely performed component of all neurological examinations. PMID:26444394

  1. Fundus Autofluorescence Imaging in an Ocular Screening Program

    Directory of Open Access Journals (Sweden)

    A. M. Kolomeyer

    2012-01-01

    Full Text Available Purpose. To describe integration of fundus autofluorescence (FAF imaging into an ocular screening program. Methods. Fifty consecutive screening participants were included in this prospective pilot imaging study. Color and FAF (530/640 nm exciter/barrier filters images were obtained with a 15.1MP Canon nonmydriatic hybrid camera. A clinician evaluated the images on site to determine need for referral. Visual acuity (VA, intraocular pressure (IOP, and ocular pathology detected by color fundus and FAF imaging modalities were recorded. Results. Mean ± SD age was 47.4 ± 17.3 years. Fifty-two percent were female and 58% African American. Twenty-seven percent had a comprehensive ocular examination within the past year. Mean VA was 20/39 in the right eye and 20/40 in the left eye. Mean IOP was 15 mmHg bilaterally. Positive color and/or FAF findings were identified in nine (18% individuals with diabetic retinopathy or macular edema (n=4, focal RPE defects (n=2, age-related macular degeneration (n=1, central serous retinopathy (n=1, and ocular trauma (n=1. Conclusions. FAF was successfully integrated in our ocular screening program and aided in the identification of ocular pathology. Larger studies examining the utility of this technology in screening programs may be warranted.

  2. Fundus autofluorescence imaging in an ocular screening program.

    Science.gov (United States)

    Kolomeyer, A M; Nayak, N V; Szirth, B C; Khouri, A S

    2012-01-01

    Purpose. To describe integration of fundus autofluorescence (FAF) imaging into an ocular screening program. Methods. Fifty consecutive screening participants were included in this prospective pilot imaging study. Color and FAF (530/640 nm exciter/barrier filters) images were obtained with a 15.1MP Canon nonmydriatic hybrid camera. A clinician evaluated the images on site to determine need for referral. Visual acuity (VA), intraocular pressure (IOP), and ocular pathology detected by color fundus and FAF imaging modalities were recorded. Results. Mean ± SD age was 47.4 ± 17.3 years. Fifty-two percent were female and 58% African American. Twenty-seven percent had a comprehensive ocular examination within the past year. Mean VA was 20/39 in the right eye and 20/40 in the left eye. Mean IOP was 15 mmHg bilaterally. Positive color and/or FAF findings were identified in nine (18%) individuals with diabetic retinopathy or macular edema (n = 4), focal RPE defects (n = 2), age-related macular degeneration (n = 1), central serous retinopathy (n = 1), and ocular trauma (n = 1). Conclusions. FAF was successfully integrated in our ocular screening program and aided in the identification of ocular pathology. Larger studies examining the utility of this technology in screening programs may be warranted.

  3. Realization of the ergonomics design and automatic control of the fundus cameras

    Science.gov (United States)

    Zeng, Chi-liang; Xiao, Ze-xin; Deng, Shi-chao; Yu, Xin-ye

    2012-12-01

    The principles of ergonomics design in fundus cameras should be extending the agreeableness by automatic control. Firstly, a 3D positional numerical control system is designed for positioning the eye pupils of the patients who are doing fundus examinations. This system consists of a electronically controlled chin bracket for moving up and down, a lateral movement of binocular with the detector and the automatic refocusing of the edges of the eye pupils. Secondly, an auto-focusing device for the object plane of patient's fundus is designed, which collects the patient's fundus images automatically whether their eyes is ametropic or not. Finally, a moving visual target is developed for expanding the fields of the fundus images.

  4. Comparison of Color Fundus Photography, Infrared Fundus Photography, and Optical Coherence Tomography in Detecting Retinal Hamartoma in Patients with Tuberous Sclerosis Complex.

    Science.gov (United States)

    Bai, Da-Yong; Wang, Xu; Zhao, Jun-Yang; Li, Li; Gao, Jun; Wang, Ning-Li

    2016-05-20

    A sensitive method is required to detect retinal hamartomas in patients with tuberous sclerosis complex (TSC). The aim of the present study was to compare the color fundus photography, infrared imaging (IFG), and optical coherence tomography (OCT) in the detection rate of retinal hamartoma in patients with TSC. This study included 11 patients (22 eyes) with TSC, who underwent color fundus photography, IFG, and spectral-domain OCT to detect retinal hamartomas. TSC1 and TSC2RESULTS: The mean age of the 11 patients was 8.0 ± 2.1 years. The mean spherical equivalent was -0.55 ± 1.42 D by autorefraction with cycloplegia. In 11 patients (22 eyes), OCT, infrared fundus photography, and color fundus photography revealed 26, 18, and 9 hamartomas, respectively. The predominant hamartoma was type I (55.6%). All the hamartomas that detected by color fundus photography or IFG can be detected by OCT. Among the methods of color fundus photography, IFG, and OCT, the OCT has higher detection rate for retinal hamartoma in TSC patients; therefore, OCT might be promising for the clinical diagnosis of TSC.

  5. Adaptive optics fundus images of cone photoreceptors in the macula of patients with retinitis pigmentosa

    Directory of Open Access Journals (Sweden)

    Tojo N

    2013-01-01

    Full Text Available Naoki Tojo, Tomoko Nakamura, Chiharu Fuchizawa, Toshihiko Oiwake, Atsushi HayashiDepartment of Ophthalmology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, JapanBackground: The purpose of this study was to examine cone photoreceptors in the macula of patients with retinitis pigmentosa using an adaptive optics fundus camera and to investigate any correlations between cone photoreceptor density and findings on optical coherence tomography and fundus autofluorescence.Methods: We examined two patients with typical retinitis pigmentosa who underwent ophthalmological examination, including measurement of visual acuity, and gathering of electroretinographic, optical coherence tomographic, fundus autofluorescent, and adaptive optics fundus images. The cone photoreceptors in the adaptive optics images of the two patients with retinitis pigmentosa and five healthy subjects were analyzed.Results: An abnormal parafoveal ring of high-density fundus autofluorescence was observed in the macula in both patients. The border of the ring corresponded to the border of the external limiting membrane and the inner segment and outer segment line in the optical coherence tomographic images. Cone photoreceptors at the abnormal parafoveal ring were blurred and decreased in the adaptive optics images. The blurred area corresponded to the abnormal parafoveal ring in the fundus autofluorescence images. Cone densities were low at the blurred areas and at the nasal and temporal retina along a line from the fovea compared with those of healthy controls. The results for cone spacing and Voronoi domains in the macula corresponded with those for the cone densities.Conclusion: Cone densities were heavily decreased in the macula, especially at the parafoveal ring on high-density fundus autofluorescence in both patients with retinitis pigmentosa. Adaptive optics images enabled us to observe in vivo changes in the cone photoreceptors of

  6. Factores asociados a complicaciones de yeyunostomía

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    H. Medina-Franco

    2013-04-01

    Conclusiones: La yeyunostomía se asocia a una elevada frecuencia de complicaciones, tanto médicas como quirúrgicas. Si bien se ha establecido como una mejor alternativa a nutrición parenteral, deberá tomarse en cuenta la morbilidad asociada a la misma antes de establecer su utilización rutinaria como medio de aporte nutricional, particularmente en pacientes con factores asociados al desarrollo de las mismas.

  7. Factores asociados a la convivencia escolar en adolescentes

    OpenAIRE

    Clara López de Mesa-Melo; César Andrés Carvajal-Castillo; María Fernanda Soto-Godoy; Pedro Nel Urrea-Roa

    2013-01-01

    El artículo presenta los resultados de una investigación sobre las condiciones y factores asociados a la convivencia escolar. El objetivo del estudio fue evaluar la convivencia escolar, mediante un estudio descriptivo y transversal en 9 instituciones educativas de 5 municipios de Cundinamarca, Colombia, en el año 2011. Participaron 1091 estudiantes y 101 profesores, los instrumentos utilizados incluyeron variables como clima escolar, agresión, factores de apoyo y riesgo, autoestima, funcional...

  8. Rapid grading of fundus photographs for diabetic retinopathy using crowdsourcing.

    Science.gov (United States)

    Brady, Christopher J; Villanti, Andrea C; Pearson, Jennifer L; Kirchner, Thomas R; Gupta, Omesh P; Shah, Chirag P

    2014-10-30

    Screening for diabetic retinopathy is both effective and cost-effective, but rates of screening compliance remain suboptimal. As screening improves, new methods to deal with screening data may help reduce the human resource needs. Crowdsourcing has been used in many contexts to harness distributed human intelligence for the completion of small tasks including image categorization. Our goal was to develop and validate a novel method for fundus photograph grading. An interface for fundus photo classification was developed for the Amazon Mechanical Turk crowdsourcing platform. We posted 19 expert-graded images for grading by Turkers, with 10 repetitions per photo for an initial proof-of-concept (Phase I). Turkers were paid US $0.10 per image. In Phase II, one prototypical image from each of the four grading categories received 500 unique Turker interpretations. Fifty draws of 1-50 Turkers were then used to estimate the variance in accuracy derived from randomly drawn samples of increasing crowd size to determine the minimum number of Turkers needed to produce valid results. In Phase III, the interface was modified to attempt to improve Turker grading. Across 230 grading instances in the normal versus abnormal arm of Phase I, 187 images (81.3%) were correctly classified by Turkers. Average time to grade each image was 25 seconds, including time to review training images. With the addition of grading categories, time to grade each image increased and percentage of images graded correctly decreased. In Phase II, area under the curve (AUC) of the receiver-operator characteristic (ROC) indicated that sensitivity and specificity were maximized after 7 graders for ratings of normal versus abnormal (AUC=0.98) but was significantly reduced (AUC=0.63) when Turkers were asked to specify the level of severity. With improvements to the interface in Phase III, correctly classified images by the mean Turker grade in four-category grading increased to a maximum of 52.6% (10/19 images

  9. Statistical characterization and segmentation of drusen in fundus images.

    Science.gov (United States)

    Santos-Villalobos, H; Karnowski, T P; Aykac, D; Giancardo, L; Li, Y; Nichols, T; Tobin, K W; Chaum, E

    2011-01-01

    Age related Macular Degeneration (AMD) is a disease of the retina associated with aging. AMD progression in patients is characterized by drusen, pigmentation changes, and geographic atrophy, which can be seen using fundus imagery. The level of AMD is characterized by standard scaling methods, which can be somewhat subjective in practice. In this work we propose a statistical image processing approach to segment drusen with the ultimate goal of characterizing the AMD progression in a data set of longitudinal images. The method characterizes retinal structures with a statistical model of the colors in the retina image. When comparing the segmentation results of the method between longitudinal images with known AMD progression and those without, the method detects progression in our longitudinal data set with an area under the receiver operating characteristics curve of 0.99.

  10. Does Fundus Fluorescein Angiography Procedure Affect Ocular Pulse Amplitude?

    Directory of Open Access Journals (Sweden)

    Gökhan Pekel

    2013-01-01

    Full Text Available Purpose. This study examines the effects of fundus fluorescein angiography (FFA procedure on ocular pulse amplitude (OPA and intraocular pressure (IOP. Materials and Methods. Sixty eyes of 30 nonproliferative diabetic retinopathy patients (15 males, 15 females were included in this cross-sectional case series. IOP and OPA were measured with the Pascal dynamic contour tonometer before and after 5 minutes of intravenous fluorescein dye injection. Results. Pre-FFA mean OPA value was  mmHg and post-FFA mean OPA value was  mmHg (. Pre-FFA mean IOP value was  mmHg and post-FFA mean IOP value was  mmHg (. Conclusion. Although both mean OPA and IOP values were decreased after FFA procedure, the difference was not statistically significant. This clinical trial is registered with Australian New Zealand Clinical Trials Registry number ACTRN12613000433707.

  11. Statistical Characterization and Segmentation of Drusen in Fundus Images

    Energy Technology Data Exchange (ETDEWEB)

    Santos-Villalobos, Hector J [ORNL; Karnowski, Thomas Paul [ORNL; Aykac, Deniz [ORNL; Giancardo, Luca [ORNL; Li, Yaquin [University of Tennessee, Knoxville (UTK); Nichols, Trent L [ORNL; Tobin Jr, Kenneth William [ORNL; Chaum, Edward [University of Tennessee, Knoxville (UTK)

    2011-01-01

    Age related Macular Degeneration (AMD) is a disease of the retina associated with aging. AMD progression in patients is characterized by drusen, pigmentation changes, and geographic atrophy, which can be seen using fundus imagery. The level of AMD is characterized by standard scaling methods, which can be somewhat subjective in practice. In this work we propose a statistical image processing approach to segment drusen with the ultimate goal of characterizing the AMD progression in a data set of longitudinal images. The method characterizes retinal structures with a statistical model of the colors in the retina image. When comparing the segmentation results of the method between longitudinal images with known AMD progression and those without, the method detects progression in our longitudinal data set with an area under the receiver operating characteristics curve of 0.99.

  12. Crowdsourcing to Evaluate Fundus Photographs for the Presence of Glaucoma.

    Science.gov (United States)

    Wang, Xueyang; Mudie, Lucy I; Baskaran, Mani; Cheng, Ching-Yu; Alward, Wallace L; Friedman, David S; Brady, Christopher J

    2017-06-01

    To assess the accuracy of crowdsourcing for grading optic nerve images for glaucoma using Amazon Mechanical Turk before and after training modules. Images (n=60) from 2 large population studies were graded for glaucoma status and vertical cup-to-disc ratio (VCDR). In the baseline trial, users on Amazon Mechanical Turk (Turkers) graded fundus photos for glaucoma and VCDR after reviewing annotated example images. In 2 additional trials, Turkers viewed a 26-slide PowerPoint training or a 10-minute video training and passed a quiz before being permitted to grade the same 60 images. Each image was graded by 10 unique Turkers in all trials. The mode of Turker grades for each image was compared with an adjudicated expert grade to determine accuracy as well as the sensitivity and specificity of Turker grading. In the baseline study, 50% of the images were graded correctly for glaucoma status and the area under the receiver operating characteristic (AUROC) was 0.75 [95% confidence interval (CI), 0.64-0.87]. Post-PowerPoint training, 66.7% of the images were graded correctly with AUROC of 0.86 (95% CI, 0.78-0.95). Finally, Turker grading accuracy was 63.3% with AUROC of 0.89 (95% CI, 0.83-0.96) after video training. Overall, Turker VCDR grades for each image correlated with expert VCDR grades (Bland-Altman plot mean difference=-0.02). Turkers graded 60 fundus images quickly and at low cost, with grading accuracy, sensitivity, and specificity, all improving with brief training. With effective education, crowdsourcing may be an efficient tool to aid in the identification of glaucomatous changes in retinal images.

  13. Characteristics of Fundus Autofluorescence in Active Polypoidal Choroidal Vasculopathy

    Directory of Open Access Journals (Sweden)

    Zafer Öztaş

    2016-08-01

    Full Text Available Objectives: To define characteristic fundus autofluorescence (FAF findings in eyes with active polypoidal choroidal vasculopathy (PCV. Materials and Methods: Thirty-five eyes of 29 patients with active PCV who were diagnosed at Ege University Faculty of Medicine, Department of Ophthalmology, Retina Division between January 2012 and November 2014 were included in the study. All the patients underwent a complete ophthalmological examination including fundus photography, spectral-domain optical coherence tomography, fluorescein angiography, FAF photography, and indocyanine green angiography (ICGA. ICGA was used to diagnose active PCV and identify lesion components. FAF findings were described at the retinal site of the corresponding lesions identified and diagnosed using ICGA. Results: The mean age of the 29 study patients (15 men, 14 women was 64.6±7.5 years (range, 54-82 years. ICGA revealed active PCV in 35 eyes, consisting of polypoid lesions in 11 eyes (31.4%, branching vascular networks (BVN in 10 eyes (28.6%, and a combination of polypoid lesions and BVNs in 14 eyes (40%. On FAF images, 4 different patterns were detected at the corresponding retinal sites of 25 polypoid lesions detected by ICGA: confluent hypoautofluorescence with a hyperautofluorescent ring in 18 eyes (72%, hyperautofluorescence with hypoautofluorescent ring in 2 eyes (8%, confluent hypoautofluorescence in 1 eye (4%, and granular hypoautofluorescence in 1 eye (4%. The remaining 3 eyes (12% demonstrated blocked hypoautofluorescence because of the excessive hemorrhaging in the macula. The FAF images showed the granular hypoautofluorescent FAF pattern in all 24 BVNs (100% consistent with the location of the lesions on ICGA. Conclusion: The typical PCV lesions, polypoid lesions and BVNs had characteristic autofluorescent findings on FAF imaging. Non-invasive, quick, and repeatable FAF imaging can be considered a reliable and helpful diagnostic technique for the diagnosis of

  14. The Portable Dynamic Fundus Instrument: Uses in telemedicine and research

    Science.gov (United States)

    Hunter, Norwood; Caputo, Michael; Billica, Roger; Taylor, Gerald; Gibson, C. Robert; Manuel, F. Keith; Mader, Thomas; Meehan, Richard

    1994-01-01

    For years ophthalmic photographs have been used to track the progression of many ocular diseases such as macular degeneration and glaucoma as well as the ocular manifestations of diabetes, hypertension, and hypoxia. In 1987 a project was initiated at the Johnson Space Center (JSC) to develop a means of monitoring retinal vascular caliber and intracranial pressure during space flight. To conduct telemedicine during space flight operations, retinal images would require real-time transmissions from space. Film-based images would not be useful during in-flight operations. Video technology is beneficial in flight because the images may be acquired, recorded, and transmitted to the ground for rapid computer digital image processing and analysis. The computer analysis techniques developed for this project detected vessel caliber changes as small as 3 percent. In the field of telemedicine, the Portable Dynamic Fundus Instrument demonstrates the concept and utility of a small, self-contained video funduscope. It was used to record retinal images during the Gulf War and to transmit retinal images from the Space Shuttle Columbia during STS-50. There are plans to utilize this device to provide a mobile ophthalmic screening service in rural Texas. In the fall of 1993 a medical team in Boulder, Colorado, will transmit real-time images of the retina during remote consultation and diagnosis. The research applications of this device include the capability of operating in remote locations or small, confined test areas. There has been interest shown utilizing retinal imaging during high-G centrifuge tests, high-altitude chamber tests, and aircraft flight tests. A new design plan has been developed to incorporate the video instrumentation into face-mounted goggle. This design would eliminate head restraint devices, thus allowing full maneuverability to the subjects. Further development of software programs will broaden the application of the Portable Dynamic Fundus Instrument in

  15. The sensitivity and specificity of one field non-mydriatic digital fundus photography for DR screening

    Directory of Open Access Journals (Sweden)

    Bin-Bin Li

    2013-07-01

    Full Text Available AIM:To evaluate the sensitivity and specificity of one-field non-mydriatic digital fundus photography and direct ophthalmoscopy for diabetic retinopathy(DRscreening, compared with fundus fluorescein angiography( FFA .METHODS:All 93 patients of type 1 or 2 diabetic who have underwent one-field non-mydriatic digital fundus photography, and direct ophthalmoscopy with dilation of their pupils, and FFA by ophthalmologists. The sensitivity and specificity of one-field non-mydriatic digital fundus photography and direct ophthalmoscopy were calculated respectively, compared with FFA.RESULTS: The sensitivity and specificity of one-field non-mydriatic digital fundus photography for detection of any DR were 80.4% and 94.7%; The sensitivity and specificity of direct ophthalmoscopy for detection of any DR were 64.2% and 84.2%; After the standard for referable DR being lowered down to the moderate non-proliferative diabetic retinopathy(M-NPDR, the sensitivity and specificity of non-mydriatic digital fundus photography for detection were 88.9% and 98.4%, the sensitivity and specificity of direct ophthalmoscopy for detection were 71.5% and 96.7%.CONCLUSION: One-field non-mydriatic digital fundus photography is an effective method for DR screening.

  16. Prevention of increased abnormal fundus autofluorescence with blue light-filtering intraocular lenses.

    Science.gov (United States)

    Nagai, Hiroyuki; Hirano, Yoshio; Yasukawa, Tsutomu; Morita, Hiroshi; Nozaki, Miho; Wolf-Schnurrbusch, Ute; Wolf, Sebastian; Ogura, Yuichiro

    2015-09-01

    To observe changes in fundus autofluorescence 2 years after implantation of blue light-filtering (yellow-tinted) and ultraviolet light-filtering (colorless) intraocular lenses (IOLs). Department of Ophthalmology and Visual Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan, and the Department of Ophthalmology, University of Bern, Bern, Switzerland. Prospective comparative observational study. Patients were enrolled who had cataract surgery with implantation of a yellow-tinted or colorless IOL and for whom images were obtained on which the fundus autofluorescence was measurable using the Heidelberg Retina Angiogram 2 postoperatively. The fundus autofluorescence in the images was classified into 8 abnormal patterns based on the classification of the International Fundus Autofluorescence Classification Group, The presence of normal fundus autofluorescence, geographic atrophy, and wet age-related macular degeneration (AMD) also was recorded. The fundus findings at baseline and 2 years postoperatively were compared. Fifty-two eyes with a yellow-tinted IOL and 79 eyes with a colorless IOL were included. Abnormal fundus autofluorescence did not develop or increase in the yellow-tinted IOL group; however, progressive abnormal fundus autofluorescence developed or increased in 12 eyes (15.2%) in the colorless IOL group (P = .0016). New drusen, geographic atrophy, and choroidal neovascularization were observed mainly in the colorless IOL group. The incidence of AMD was statistically significantly higher in the colorless IOL group (P = .042). Two years after cataract surgery, significant differences were seen in the progression of abnormal fundus autofluorescence between the 2 groups. The incidence of AMD was lower in eyes with a yellow-tinted IOL. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  17. Imperceptible watermarking for security of fundus images in tele-ophthalmology applications and computer-aided diagnosis of retina diseases.

    Science.gov (United States)

    Singh, Anushikha; Dutta, Malay Kishore

    2017-12-01

    The authentication and integrity verification of medical images is a critical and growing issue for patients in e-health services. Accurate identification of medical images and patient verification is an essential requirement to prevent error in medical diagnosis. The proposed work presents an imperceptible watermarking system to address the security issue of medical fundus images for tele-ophthalmology applications and computer aided automated diagnosis of retinal diseases. In the proposed work, patient identity is embedded in fundus image in singular value decomposition domain with adaptive quantization parameter to maintain perceptual transparency for variety of fundus images like healthy fundus or disease affected image. In the proposed method insertion of watermark in fundus image does not affect the automatic image processing diagnosis of retinal objects & pathologies which ensure uncompromised computer-based diagnosis associated with fundus image. Patient ID is correctly recovered from watermarked fundus image for integrity verification of fundus image at the diagnosis centre. The proposed watermarking system is tested in a comprehensive database of fundus images and results are convincing. results indicate that proposed watermarking method is imperceptible and it does not affect computer vision based automated diagnosis of retinal diseases. Correct recovery of patient ID from watermarked fundus image makes the proposed watermarking system applicable for authentication of fundus images for computer aided diagnosis and Tele-ophthalmology applications. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Servicios auxiliares asociados al transporte marítimo

    OpenAIRE

    Godes Gallardo, Daniel

    2014-01-01

    En este proyecto, mi intención es profundizar en los servicios auxiliares asociados al transporte marítimo, como su título indica. En él haré referencia a todos los servicios que el transporte marítimo en sí, y más en concreto los buques, utilizan cada vez que entran a puerto.En algunos casos, estos servicios no se prestan en las instalaciones del puerto, como pueden ser los servicios exclusivospara la explotación comercial del buque. Hay que tener en cuenta que, se podría hacer un trabajo...

  19. ERITEMA NODOSO Y SINDROME FEBRIL PROLONGADO ASOCIADOS A HIPERPARATIROIDISMO SECUNDARIO

    Directory of Open Access Journals (Sweden)

    Enz P

    2005-06-01

    Full Text Available El hiperparatiroidismo secundario es uno de los principales disturbios causados por la insuficiencia renal crónica, y la paratohormona es considerada una de las toxinas del sindrome urémico. El sindrome febril prolongado secundario a hiperparatiroidismo primario ya ha sido descripto en la literatura, aunque no lo ha sido aun el inducido por hiperparatiroidismo secundario. En el presente reporte se presenta un caso de eritema nodoso y sindrome febril prolongado asociado a hiperparatiroidismo secundario y que resolvió luego de efectuada una paratiroidectomía subtotal.

  20. Cambios neuropsicológicos asociados al envejecimiento normal

    OpenAIRE

    Román Lapuente, Francisco; Sánchez Navarro, Juan Pedro

    1998-01-01

    Esta revisión ofrece un marco neuropsicológico relacionado con las variaciones tanto a nivel neurobiológico como cognitivo durante el envejecimiento. En la actualidad se cuestiona si el envejecimiento en sí conlleva una serie de cambios neuropsicológicos o si estos cambios pueden estar asociados a diferentes condiciones de salud que tienden a presentarse con más frecuencia en las personas mayores. En general, los trabajos revisados sugieren que el envejecimient...

  1. Factores asociados al maltrato del adulto mayor de Antioquia, 2012

    OpenAIRE

    Sara M. Cano; María O. Garzón; Ángela M. Segura; Doris Cardona

    2015-01-01

    Objetivo: determinar los factores asociados al maltrato del adulto mayor del departamento de Antioquia en el año 2012. Metodología: mediante estudio descriptivo transversal, se caracterizaron los factores demográficos, económicos y de salud mental de la población adulta mayor de Antioquia para el año 2012, con el fin de aportar al análisis de la situación de salud y condiciones de vida del adulto mayor. El estudio se basó en los resultados del instrumento aplicado por la Universidad ces a 4.2...

  2. Interpretations of Fundus Autofluorescence from Studies of the Bisretinoids of the Retina

    OpenAIRE

    Sparrow, Janet R.; Yoon, Kee Dong; Wu, Yalin; Yamamoto, Kazunori

    2010-01-01

    Elevated fundus autofluorescence signals can reflect enhanced lipofuscin in RPE cells, augmented fluorescence due to photooxidation, and/or excess bisretinoid fluorophores in photoreceptor cells due to mishandling of vitamin A aldehyde by dysfunctional cells.

  3. Adaptive optics scanning laser ophthalmoscopy in fundus imaging, a review and update

    Directory of Open Access Journals (Sweden)

    Bing Zhang

    2017-11-01

    Full Text Available Adaptive optics scanning laser ophthalmoscopy (AO-SLO has been a promising technique in funds imaging with growing popularity. This review firstly gives a brief history of adaptive optics (AO and AO-SLO. Then it compares AO-SLO with conventional imaging methods (fundus fluorescein angiography, fundus autofluorescence, indocyanine green angiography and optical coherence tomography and other AO techniques (adaptive optics flood-illumination ophthalmoscopy and adaptive optics optical coherence tomography. Furthermore, an update of current research situation in AO-SLO is made based on different fundus structures as photoreceptors (cones and rods, fundus vessels, retinal pigment epithelium layer, retinal nerve fiber layer, ganglion cell layer and lamina cribrosa. Finally, this review indicates possible research directions of AO-SLO in future.

  4. Application of smart phone and supporting set for fundus imaging in primary hospital of rural area

    Directory of Open Access Journals (Sweden)

    Yong-Feng Jing

    2018-01-01

    Full Text Available AIM: To describe the application of smart phone and supporting set for acquiring fundus images with slitlamp examination and non-contact lens in primary hospital of the rural area. METHODS: The supporting set for smart phone was purchased from taobao and securely connected to the ocular lens of slitlamp microscopy. The fundus photos were imaged with assistance of non-contact slitlamp lens from Volk. RESULTS: High quality images of various retinal diseases could be successfully taken with smart phone and supporting set by slitlamp examination. The fundus images were send to patients with Wechat as medical records or used for telconsultant. CONCLUSION: High resolution smart phones are wildly used nowadays and supporting sets are very accessible; thus high quality of images could be obtained with minimal cost in rural hospitals. The digital fundus images will be beneficial for medical record and rapid diagnosis with telconsultant.

  5. Reliability and reproducibility of disc-foveal angle measurements by non-mydriatic fundus photography

    OpenAIRE

    Le Jeune, Caroline; Chebli, Fayçal; Leon, Lorette; Anthoine, Emmanuelle; Weber, Michel; Péchereau, Alain; Lebranchu, Pierre

    2018-01-01

    Purpose Abnormal torsion could be associated with cyclovertical strabismus, but torsion measurements are not reliable in children. To assess an objective fundus torsion evaluation in a paediatric population, we used Non-Mydriatic Fundus photography (NMFP) in healthy and cyclovertical strabismus patients to evaluate the disc-foveal angle over time and observers. Methods We used a retrospective set of NMFP including 24 A or V-pattern strabismus and 27 age-matched normal children (mean age 6.4 a...

  6. Adaptive optics fundus images of cone photoreceptors in the macula of patients with retinitis pigmentosa.

    Science.gov (United States)

    Tojo, Naoki; Nakamura, Tomoko; Fuchizawa, Chiharu; Oiwake, Toshihiko; Hayashi, Atsushi

    2013-01-01

    The purpose of this study was to examine cone photoreceptors in the macula of patients with retinitis pigmentosa using an adaptive optics fundus camera and to investigate any correlations between cone photoreceptor density and findings on optical coherence tomography and fundus autofluorescence. We examined two patients with typical retinitis pigmentosa who underwent ophthalmological examination, including measurement of visual acuity, and gathering of electroretinographic, optical coherence tomographic, fundus autofluorescent, and adaptive optics fundus images. The cone photoreceptors in the adaptive optics images of the two patients with retinitis pigmentosa and five healthy subjects were analyzed. An abnormal parafoveal ring of high-density fundus autofluorescence was observed in the macula in both patients. The border of the ring corresponded to the border of the external limiting membrane and the inner segment and outer segment line in the optical coherence tomographic images. Cone photoreceptors at the abnormal parafoveal ring were blurred and decreased in the adaptive optics images. The blurred area corresponded to the abnormal parafoveal ring in the fundus autofluorescence images. Cone densities were low at the blurred areas and at the nasal and temporal retina along a line from the fovea compared with those of healthy controls. The results for cone spacing and Voronoi domains in the macula corresponded with those for the cone densities. Cone densities were heavily decreased in the macula, especially at the parafoveal ring on high-density fundus autofluorescence in both patients with retinitis pigmentosa. Adaptive optics images enabled us to observe in vivo changes in the cone photoreceptors of patients with retinitis pigmentosa, which corresponded to changes in the optical coherence tomographic and fundus autofluorescence images.

  7. Incidence of fundus oculi and neurocranium changes in patients with migraine in the community

    Directory of Open Access Journals (Sweden)

    M. Musić

    2005-02-01

    Full Text Available The purpose of this study was to monitor possible changes of fundus oculi and neurocranim in patients with migraine according to their gender, place of residence and education grade. In a significantpercentageofourpatients with migraine there were no changes of fundus oculi, CT neurocranium or craniogram. The reason of significantmigrainemorbidityinruralzones,inpatientswithlowereducationgrade,andalmostequalproportionof male and female patients with tendency of the disease to older age groups, remains unclear. There is a need for further research.

  8. Effect of isoproterenol, phenylephrine, and sodium nitroprusside on fundus pulsations in healthy volunteers.

    OpenAIRE

    Schmetterer, L; Wolzt, M; Salomon, A; Rheinberger, A; Unfried, C; Zanaschka, G; Fercher, A F

    1996-01-01

    AIMS/BACKGROUND: Recently a laser interferometric method for topical measurement of fundus pulsations has been developed. Fundus pulsations in the macular region are caused by the inflow and outflow of blood into the choroid. The purpose of this work was to study the influence of a peripheral vasoconstricting (the alpha 1 adrenoceptor agonist phenylephrine), a predominantly positive inotropic (the non-specific beta adrenoceptor agonist isoproterenol), and a non-specific vasodilating (sodium n...

  9. Imaging autofluorescence temporal signatures of the human ocular fundus in vivo

    Science.gov (United States)

    Papour, Asael; Taylor, Zachary; Stafsudd, Oscar; Tsui, Irena; Grundfest, Warren

    2015-11-01

    We demonstrate real-time in vivo fundus imaging capabilities of our fluorescence lifetime imaging technology for the first time. This implementation of lifetime imaging uses light emitting diodes to capture full-field images capable of showing direct tissue contrast without executing curve fitting or lifetime calculations. Preliminary results of fundus images are presented, investigating autofluorescence imaging potential of various retina biomarkers for early detection of macular diseases.

  10. Adaptive optics scanning laser ophthalmoscopy in fundus imaging, a review and update

    OpenAIRE

    Zhang, Bing; Li, Ni; Kang, Jie; He, Yi; Chen, Xiao-Ming

    2017-01-01

    Adaptive optics scanning laser ophthalmoscopy (AO-SLO) has been a promising technique in funds imaging with growing popularity. This review firstly gives a brief history of adaptive optics (AO) and AO-SLO. Then it compares AO-SLO with conventional imaging methods (fundus fluorescein angiography, fundus autofluorescence, indocyanine green angiography and optical coherence tomography) and other AO techniques (adaptive optics flood-illumination ophthalmoscopy and adaptive optics optical coherenc...

  11. Screening for diabetic retinopathy in rural area using single-field, digital fundus images.

    Science.gov (United States)

    Ruamviboonsuk, Paisan; Wongcumchang, Nattapon; Surawongsin, Pattamaporn; Panyawatananukul, Ekchai; Tiensuwan, Montip

    2005-02-01

    To evaluate the practicability of using single-field, 2.3 million-pixel, digital fundus images for screening of diabetic retinopathy in rural areas. All diabetic patients who regularly attended the diabetic clinic at Kabcheang Community Hospital, located at 15 kilometers from the Thailand-Cambodia border, were appointed to the hospital for a 3-day diabetic retinopathy screening programme. The fundi of all patients were captured in single-field, 45 degrees, 2.3 million-pixel images using nonmydriatic digital fundus camera and then sent to a reading center in Bangkok. The fundi were also examined through dilated pupils by a retinal specialist at this hospital. The grading of diabetic retinopathy from two methods was compared for an exact agreement. The average duration of single digital fundus image capture was 2 minutes. The average file size of each image was 750 kilobytes. The average duration of single image transmission to a reading center in Bangkok via satellite was 3 minutes; via a conventional telephone line was 8 minutes. Of all 150 patients, 130 were assessed for an agreement between dilated fundus examination and digital fundus images in diagnosis of diabetic retinopathy. The exact agreement was 0.87, the weighted kappa statistics was 0.74. The sensitivity of digital fundus images in detecting diabetic retinopathy was 80%, the specificity was 96%. For diabetic macular edema the exact agreement was 0.97, the weighted kappa was 0.43, the sensitivity was 43%, and the specificity was 100%. The image capture of the nonmydriatic digital fundus camera is suitable for screening of diabetic retinopathy and single-field digital fundus images are potentially acceptable tools for the screening. The real-time image transmission via telephone lines to remote reading center, however, may not be practical for routine diabetic retinopathy screening in rural areas.

  12. Opinion and Special Articles: Amateur fundus photography with various new devices: Our experience as neurology residents.

    Science.gov (United States)

    Zafar, Saman; Cardenas, Ylec Mariana; Leishangthem, Lakshmi; Yaddanapudi, Sridhara

    2018-05-08

    Times are changing in the way we secure and share patient fundus photographs to enhance our diagnostic skills in neurology. At the recent American Academy of Neurology meeting, the use of a fundus camera and smartphones to secure good-quality fundus photographs of patients presenting with headache to the emergency department (ED) was presented. We were enthusiastic to replicate the success of the Fundus Photography vs Ophthalmoscopy Trial Outcomes in the Emergency Department (FOTO-ED) study in our neurology department, but encountered problems in terms of cost, setup, feasibility, and portability of the device. As neurology residents, we came up with 3 easier options. We present these 3 options as our personal experience, and hope to reignite enthusiasm among neurology trainees to find their own means of performing ophthalmoscopy routinely in the hospital, as it appears that the Internet market is now thriving with many other devices to make this examination easier and more rewarding. Of the options explored above, the Handheld Fundus Camera was a clear favorite among the residents, and we have placed one in our call room for routine use. It travels to the clinic, floor, intensive care unit, and ED when needed. It has enhanced the way we approach the fundus examination and been a fun skill to acquire. We look forward to further advances that will make it possible to carry such a device in a physician's pocket. © 2018 American Academy of Neurology.

  13. The Role of Fundus Autofluorescence in Late-Onset Retinitis Pigmentosa (LORP) Diagnosis

    Science.gov (United States)

    Lee, Tamara J.; Hwang, John C.; Chen, Royce W. S.; Lima, Luiz H.; Wang, Nan-Kai; Tosi, Joaquin; Freund, K. Bailey; Yannuzzi, Lawrence A.; Tsang, Stephen H.

    2015-01-01

    Purpose To demonstrate the utility and characteristics of fundus autofluorescence in late-onset retinitis pigmentosa. Methods Observational case series. Patients diagnosed with late-onset retinitis pigmentosa were identified retrospectively in an institutional setting. Twelve eyes of six patients were identified and medical records were reviewed. Results All patients presented with slowly progressive peripheral field loss and initial clinical examination revealed only subtle retinal changes. There was a notable lack of intraretinal pigment migration in all patients. Five out of six patients underwent magnetic resonance imaging of the brain to rule out intracranial processes and all were referred from another ophthalmologist for further evaluation. Fundus autofluorescence was ultimately employed in all patients and revealed more extensive retinal pathology than initially appreciated on clinical examination. Fundus autofluorescence directed the workup toward a retinal etiology in all cases and led to the eventual diagnosis of late-onset retinitis pigmentosa through electroretinogram testing. Conclusion Fundus autofluorescence may be a more sensitive marker for retinal pathology than stereo fundus biomicroscopy alone in late-onset retinitis pigmentosa. Early use of fundus autofluorescence imaging in the evaluation of patients with subtle retinal lesions and complaints of peripheral field loss may be an effective strategy for timely and cost-efficient diagnosis. PMID:23899229

  14. A Portable, Inexpensive, Nonmydriatic Fundus Camera Based on the Raspberry Pi® Computer

    Directory of Open Access Journals (Sweden)

    Bailey Y. Shen

    2017-01-01

    Full Text Available Purpose. Nonmydriatic fundus cameras allow retinal photography without pharmacologic dilation of the pupil. However, currently available nonmydriatic fundus cameras are bulky, not portable, and expensive. Taking advantage of recent advances in mobile technology, we sought to create a nonmydriatic fundus camera that was affordable and could be carried in a white coat pocket. Methods. We built a point-and-shoot prototype camera using a Raspberry Pi computer, an infrared-sensitive camera board, a dual infrared and white light light-emitting diode, a battery, a 5-inch touchscreen liquid crystal display, and a disposable 20-diopter condensing lens. Our prototype camera was based on indirect ophthalmoscopy with both infrared and white lights. Results. The prototype camera measured 133mm×91mm×45mm and weighed 386 grams. The total cost of the components, including the disposable lens, was $185.20. The camera was able to obtain good-quality fundus images without pharmacologic dilation of the pupils. Conclusion. A fully functional, inexpensive, handheld, nonmydriatic fundus camera can be easily assembled from a relatively small number of components. With modest improvements, such a camera could be useful for a variety of healthcare professionals, particularly those who work in settings where a traditional table-mounted nonmydriatic fundus camera would be inconvenient.

  15. Fundus oculi pigmentation studies simulating the fs-LASIK process

    Energy Technology Data Exchange (ETDEWEB)

    Sander, M; Tetz, M R [Berlin Eye Research Institute, Alt Moabit 101b, 10559 Berlin (Germany); Minet, O; Zabarylo, U [Charite Centrum 6, Arbeitsgruppe Medizinische Physik/Optische Diagnostik, Fabeckstrasse 60–62, 14195 Berlin (Germany); Mueller, M [Augenklinik Ahaus, Am Schlossgraben 13, 48683 Ahaus (Germany)

    2012-06-15

    The femtosecond-laser in situ keratomileusis (fs-LASIK) technique has successfully entered the refractive surgery market to correct ametropia by cutting transparent corneal tissue with ultra-short laser pulses based on photodisruption. The laser pulses in the near infrared range (NIR) generate a laser-induced breakdown (LIOB) in the cornea. By propagating through the eye, a certain amount of the pulse is deposited in the cornea and the remaining energy interacts with the strong absorbing tissue behind. Due to the absorption by the retinal pigment epithelium and the transfer of the thermal energy to surrounding tissue, the transmitted energy can induce damage to the retina. The aim of this project was to find out the threshold influences concerning the tissue and the correlation between the results of the macroscopical appraisal and the fundus oculi pigmentation by simulating the fs-LASIK procedure with two various laser systems in the continuous wave (CW) and fs-regime. Therefore ex-vivo determinations were carried out macroscopically and histopathologically on porcine tissue.

  16. Fundus oculi pigmentation studies simulating the fs-LASIK process

    International Nuclear Information System (INIS)

    Sander, M; Tetz, M R; Minet, O; Zabarylo, U; Mueller, M

    2012-01-01

    The femtosecond-laser in situ keratomileusis (fs-LASIK) technique has successfully entered the refractive surgery market to correct ametropia by cutting transparent corneal tissue with ultra-short laser pulses based on photodisruption. The laser pulses in the near infrared range (NIR) generate a laser-induced breakdown (LIOB) in the cornea. By propagating through the eye, a certain amount of the pulse is deposited in the cornea and the remaining energy interacts with the strong absorbing tissue behind. Due to the absorption by the retinal pigment epithelium and the transfer of the thermal energy to surrounding tissue, the transmitted energy can induce damage to the retina. The aim of this project was to find out the threshold influences concerning the tissue and the correlation between the results of the macroscopical appraisal and the fundus oculi pigmentation by simulating the fs-LASIK procedure with two various laser systems in the continuous wave (CW) and fs-regime. Therefore ex-vivo determinations were carried out macroscopically and histopathologically on porcine tissue

  17. Clinical relevance of quantified fundus autofluorescence in diabetic macular oedema.

    Science.gov (United States)

    Yoshitake, S; Murakami, T; Uji, A; Unoki, N; Dodo, Y; Horii, T; Yoshimura, N

    2015-05-01

    To quantify the signal intensity of fundus autofluorescence (FAF) and evaluate its association with visual function and optical coherence tomography (OCT) findings in diabetic macular oedema (DMO). We reviewed 103 eyes of 78 patients with DMO and 30 eyes of 22 patients without DMO. FAF images were acquired using Heidelberg Retina Angiograph 2, and the signal levels of FAF in the individual subfields of the Early Treatment Diabetic Retinopathy Study grid were measured. We evaluated the association between quantified FAF and the logMAR VA and OCT findings. One hundred and three eyes with DMO had lower FAF signal intensity levels in the parafoveal subfields compared with 30 eyes without DMO. The autofluorescence intensity in the parafoveal subfields was associated negatively with logMAR VA and the retinal thickness in the corresponding subfields. The autofluorescence levels in the parafoveal subfield, except the nasal subfield, were lower in eyes with autofluorescent cystoid spaces in the corresponding subfield than in those without autofluorescent cystoid spaces. The autofluorescence level in the central subfield was related to foveal cystoid spaces but not logMAR VA or retinal thickness in the corresponding area. Quantified FAF in the parafovea has diagnostic significance and is clinically relevant in DMO.

  18. Fundus Autofluorescence and Spectral Domain OCT in Central Serous Chorioretinopathy

    Directory of Open Access Journals (Sweden)

    Luiz Roisman

    2011-01-01

    Full Text Available Background. To describe the standard autofluorescence (FAF, the near infrared autofluorescence (NIA and optical coherence tomography (OCT patterns in central serous chorioretinopathy, correlating them with fluorescein angiography. Methods. Cross-sectional observational study, in which patients with at least seven months of CSC underwent ophthalmologic examination, fundus photography, FAF, NIA, fluorescein angiography (FA, and spectral-domain OCT. Results. Seventeen eyes of thirteen patients were included. The presentation features were a mottled hyperFAF in the detached area and areas with pigment mottling. NIA images showed areas of hyperNIA similar to FAF and localized areas of hypoNIA, which correlated with the points of leakage in the FA. OCT showed pigment epithelium detachment at the location of these hypoNIA spots. Discussion. FAF showed increased presence of fluorophores in the area of retinal detachment, which is believed to appear secondary to lipofuscin accumulation in the RPE or the presence of debris in the subretinal fluid. NIA has been related to the choroidal melanin content and there were areas of both increased and decreased NIA, which could be explained by damage ahead the retina, basically RPE and choroid. These findings, along with the PEDs found in the areas of hypoNIA, support the notion of a primary choroidal disease in CSC.

  19. Interactive segmentation for geographic atrophy in retinal fundus images.

    Science.gov (United States)

    Lee, Noah; Smith, R Theodore; Laine, Andrew F

    2008-10-01

    Fundus auto-fluorescence (FAF) imaging is a non-invasive technique for in vivo ophthalmoscopic inspection of age-related macular degeneration (AMD), the most common cause of blindness in developed countries. Geographic atrophy (GA) is an advanced form of AMD and accounts for 12-21% of severe visual loss in this disorder [3]. Automatic quantification of GA is important for determining disease progression and facilitating clinical diagnosis of AMD. The problem of automatic segmentation of pathological images still remains an unsolved problem. In this paper we leverage the watershed transform and generalized non-linear gradient operators for interactive segmentation and present an intuitive and simple approach for geographic atrophy segmentation. We compare our approach with the state of the art random walker [5] algorithm for interactive segmentation using ROC statistics. Quantitative evaluation experiments on 100 FAF images show a mean sensitivity/specificity of 98.3/97.7% for our approach and a mean sensitivity/specificity of 88.2/96.6% for the random walker algorithm.

  20. Automated retinal vessel type classification in color fundus images

    Science.gov (United States)

    Yu, H.; Barriga, S.; Agurto, C.; Nemeth, S.; Bauman, W.; Soliz, P.

    2013-02-01

    Automated retinal vessel type classification is an essential first step toward machine-based quantitative measurement of various vessel topological parameters and identifying vessel abnormalities and alternations in cardiovascular disease risk analysis. This paper presents a new and accurate automatic artery and vein classification method developed for arteriolar-to-venular width ratio (AVR) and artery and vein tortuosity measurements in regions of interest (ROI) of 1.5 and 2.5 optic disc diameters from the disc center, respectively. This method includes illumination normalization, automatic optic disc detection and retinal vessel segmentation, feature extraction, and a partial least squares (PLS) classification. Normalized multi-color information, color variation, and multi-scale morphological features are extracted on each vessel segment. We trained the algorithm on a set of 51 color fundus images using manually marked arteries and veins. We tested the proposed method in a previously unseen test data set consisting of 42 images. We obtained an area under the ROC curve (AUC) of 93.7% in the ROI of AVR measurement and 91.5% of AUC in the ROI of tortuosity measurement. The proposed AV classification method has the potential to assist automatic cardiovascular disease early detection and risk analysis.

  1. [The cell phones as devices for the ocular fundus documentation].

    Science.gov (United States)

    Němčanský, J; Kopecký, A; Timkovič, J; Mašek, P

    2014-12-01

    To present our experience with "smart phones" when examining and documenting human eyes. From September to October 2013 fifteen patients (8 men, 7 women) eye fundus was examined, an average age during the examination was 58 year (ranging from 20-65 years). The photo-documentation was performed with dilated pupils (tropicamid hydrochloridum 1% eye drops) with mobile phone Samsung Galaxy Nexus with the operating system Android 4.3 (Google Inc., Mountain View, CA, USA) and iPhone 4 with the operating system 7.0.4 (Apple Inc., Loop Cupertino, CA, USA), and with 20D lens (Volk Optical Inc., Mentor, OH, USA). The images of the retina taken with a mobile phone and the spherical lens are of a very good quality, precise and reproducible. Learning this technique is easy and fast, the learning curve is steep. Photo-documentation of retina with a mobile phone is a safe, time-saving, easy-to-learn technique, which may be used in a routine ophthalmologic practice. The main advantage of this technique is availability, small size and easy portability of the devices.

  2. Extraction of Capillary Non-perfusion from Fundus Fluorescein Angiogram

    Science.gov (United States)

    Sivaswamy, Jayanthi; Agarwal, Amit; Chawla, Mayank; Rani, Alka; Das, Taraprasad

    Capillary Non-Perfusion (CNP) is a condition in diabetic retinopathy where blood ceases to flow to certain parts of the retina, potentially leading to blindness. This paper presents a solution for automatically detecting and segmenting CNP regions from fundus fluorescein angiograms (FFAs). CNPs are modelled as valleys, and a novel technique based on extrema pyramid is presented for trough-based valley detection. The obtained valley points are used to segment the desired CNP regions by employing a variance-based region growing scheme. The proposed algorithm has been tested on 40 images and validated against expert-marked ground truth. In this paper, we present results of testing and validation of our algorithm against ground truth and compare the segmentation performance against two others methods.The performance of the proposed algorithm is presented as a receiver operating characteristic (ROC) curve. The area under this curve is 0.842 and the distance of ROC from the ideal point (0,1) is 0.31. The proposed method for CNP segmentation was found to outperform the watershed [1] and heat-flow [2] based methods.

  3. Fundus Photography in the 21st Century--A Review of Recent Technological Advances and Their Implications for Worldwide Healthcare.

    Science.gov (United States)

    Panwar, Nishtha; Huang, Philemon; Lee, Jiaying; Keane, Pearse A; Chuan, Tjin Swee; Richhariya, Ashutosh; Teoh, Stephen; Lim, Tock Han; Agrawal, Rupesh

    2016-03-01

    The introduction of fundus photography has impacted retinal imaging and retinal screening programs significantly. Fundus cameras play a vital role in addressing the cause of preventive blindness. More attention is being turned to developing countries, where infrastructure and access to healthcare are limited. One of the major limitations for tele-ophthalmology is restricted access to the office-based fundus camera. Recent advances in access to telecommunications coupled with introduction of portable cameras and smartphone-based fundus imaging systems have resulted in an exponential surge in available technologies for portable fundus photography. Retinal cameras in the near future would have to cater to these needs by featuring a low-cost, portable design with automated controls and digitalized images with Web-based transfer. In this review, we aim to highlight the advances of fundus photography for retinal screening as well as discuss the advantages, disadvantages, and implications of the various technologies that are currently available.

  4. Fundus oculi pigmentation studies simulating the fs-LASIK process Fundus oculi pigmentation studies simulating the fs-LASIK process

    Science.gov (United States)

    Sander, M.; Minet, O.; Zabarylo, U.; Müller, M.; Tetz, M. R.

    2012-06-01

    The femtosecond-laser in situ keratomileusis (fs-LASIK) technique has successfully entered the refractive surgery market to correct ametropia by cutting transparent corneal tissue with ultra-short laser pulses based on photodisruption. The laser pulses in the near infrared range (NIR) generate a laser-induced breakdown (LIOB) in the cornea. By propagating through the eye, a certain amount of the pulse is deposited in the cornea and the remaining energy interacts with the strong absorbing tissue behind. Due to the absorption by the retinal pigment epithelium and the transfer of the thermal energy to surrounding tissue, the transmitted energy can induce damage to the retina. The aim of this project was to find out the threshold influences concerning the tissue and the correlation between the results of the macroscopical appraisal and the fundus oculi pigmentation by simulating the fs-LASIK procedure with two various laser systems in the continuous wave (CW) and fs-regime. Therefore ex-vivo determinations were carried out macroscopically and histopathologically on porcine tissue.

  5. Automated Detection of Glaucoma From Topographic Features of the Optic Nerve Head in Color Fundus Photographs.

    Science.gov (United States)

    Chakrabarty, Lipi; Joshi, Gopal Datt; Chakravarty, Arunava; Raman, Ganesh V; Krishnadas, S R; Sivaswamy, Jayanthi

    2016-07-01

    To describe and evaluate the performance of an automated CAD system for detection of glaucoma from color fundus photographs. Color fundus photographs of 2252 eyes from 1126 subjects were collected from 2 centers: Aravind Eye Hospital, Madurai and Coimbatore, India. The images of 1926 eyes (963 subjects) were used to train an automated image analysis-based system, which was developed to provide a decision on a given fundus image. A total of 163 subjects were clinically examined by 2 ophthalmologists independently and their diagnostic decisions were recorded. The consensus decision was defined to be the clinical reference (gold standard). Fundus images of eyes with disagreement in diagnosis were excluded from the study. The fundus images of the remaining 314 eyes (157 subjects) were presented to 4 graders and their diagnostic decisions on the same were collected. The performance of the system was evaluated on the 314 images, using the reference standard. The sensitivity and specificity of the system and 4 independent graders were determined against the clinical reference standard. The system achieved an area under receiver operating characteristic curve of 0.792 with a sensitivity of 0.716 and specificity of 0.717 at a selected threshold for the detection of glaucoma. The agreement with the clinical reference standard as determined by Cohen κ is 0.45 for the proposed system. This is comparable to that of the image-based decisions of 4 ophthalmologists. An automated system was presented for glaucoma detection from color fundus photographs. The overall evaluation results indicated that the presented system was comparable in performance to glaucoma classification by a manual grader solely based on fundus image examination.

  6. [Fluorescein angiography and optical coherence tomography findings in central fundus of myopic patients].

    Science.gov (United States)

    Avetisov, S E; Budzinskaya, M V; Zhabina, O A; Andreeva, I V; Plyukhova, A A; Kobzova, M V; Musaeva, G M

    2015-01-01

    Myopia prevalence grows alike in many countries, including Russia, regardless of geographical and population conditions. to assess fundus changes in myopic patients at different ocular axial lengths by means of modern diagnostic tools. The study enrolled 97 patients (194 eyes) aged 45 ± 20.17 years with myopia of different degrees. Besides a standard ophthalmic examination, all patients underwent fundus fluorescein angiography and optical coherence tomography. The occurrence of retinal pigment epithelium (RPE) atrophy (diffuse or focal) has been shown to increase with increasing ocular axial length. Only 27 eyes (28.1%) appeared intact. As myopia progression implies axial growth of the eye, it is associated with a more severe decrease in choroid, RPE, and photoreceptor layer thicknesses: the longer the anterior-posterior axis, the thinner the above mentioned fundus structures. Age-related changes in the fundus are also likely to be more pronounced in longer axes. Myopic traction maculopathy, which in our case appeared the main cause of increased retinal thickness, was diagnosed in 105 eyes, "outer" macular retinoschisis--in 40 eyes. Thus, modern diagnostic tools, such as fluorescein angiography and optical coherence tomography, enable objective assessment of the central fundus.

  7. A Case of Fundus Oculi Albinoticus Diagnosed as Angelman Syndrome by Genetic Testing

    Directory of Open Access Journals (Sweden)

    Yurie Fukiyama

    2018-02-01

    Full Text Available Purpose: To report a case of fundus oculi albinoticus diagnosed as Angelman syndrome (AS via genetic testing. Case Report: This study reports on a 4-year-old boy. Since he had been having respiratory disturbance since birth, he underwent a complete physical examination to investigate the cause. The results indicated that he had various brain congenital abnormalities, such as a thin corpus callosum, as well as hydronephrosis, an atrial septal defect, and skin similar to patients with fundus oculi albinoticus. Examination revealed bilateral fundus oculi albinoticus, mild iridic hypopigmentation, optic atrophy, and poor visual tracking. Genetic testing revealed a deletion in the Prader-Willi syndrome/AS region on chromosome 15, and together with the results of methylation analysis, his condition was diagnosed as AS. Follow-up examinations revealed no change in the fundus oculi albinoticus and optic atrophy, nor did they indicate poor visual tracking. Conclusions: When fundus oculi albinoticus and optic atrophy are observed in patients with multiple malformations, AS should be considered as a differential diagnosis.

  8. Application of RetCamⅡ in the screening of neonatal fundus disease

    Directory of Open Access Journals (Sweden)

    Zhi-Gang Xiao

    2013-08-01

    Full Text Available AIM: To investigate the safe and reliable examination method for neonatal fundus screening.METHODS: Fundus information of 2 836 neonates performed by RetCamⅡ in our hospital from January 1, 2012 to December 31, 2012 were retrospectively analyzed, including 1 625 cases(57.30%of premature infants which were first examined 1-4 weeks after birth and 1 211 cases(42.70%of term infants which were first examined within 4 weeks after birth.RESULTS: Totally 454 cases of abnormalfundus were found, including 207 cases(12.74%of retinopathy of prematurity(ROP, ROPⅠ in 118 cases(57%, ROPⅡ in 58 cases(28.02%, ROPⅢ in 23 cases(11.11%, ROPⅣ in 8 cases(3.86%, no case of ROPV. A total of 247(20.40%term infants had abnormal fundus, of which 68 cases(27.53%were developmental or hereditary disease, retinoblastoma in 1 case(0.40%, retinal hemorrhage in 102 cases(41.30%, retinal exudative changes in 68 cases(27.53%, optic atrophy in 5 cases(2.02%and optic disc edema in 3 cases(1.21%.CONCLUSION: Neonatal fundus diseases were so various and harmful that early screening should be attended to. Premature infants and term infants with high risk are treated as focus group of fundus screening and RetCamII examination is safe and effective.

  9. Diagnosing and Ranking Retinopathy Disease Level Using Diabetic Fundus Image Recuperation Approach

    Directory of Open Access Journals (Sweden)

    K. Somasundaram

    2015-01-01

    Full Text Available Retinal fundus images are widely used in diagnosing different types of eye diseases. The existing methods such as Feature Based Macular Edema Detection (FMED and Optimally Adjusted Morphological Operator (OAMO effectively detected the presence of exudation in fundus images and identified the true positive ratio of exudates detection, respectively. These mechanically detected exudates did not include more detailed feature selection technique to the system for detection of diabetic retinopathy. To categorize the exudates, Diabetic Fundus Image Recuperation (DFIR method based on sliding window approach is developed in this work to select the features of optic cup in digital retinal fundus images. The DFIR feature selection uses collection of sliding windows with varying range to obtain the features based on the histogram value using Group Sparsity Nonoverlapping Function. Using support vector model in the second phase, the DFIR method based on Spiral Basis Function effectively ranks the diabetic retinopathy disease level. The ranking of disease level on each candidate set provides a much promising result for developing practically automated and assisted diabetic retinopathy diagnosis system. Experimental work on digital fundus images using the DFIR method performs research on the factors such as sensitivity, ranking efficiency, and feature selection time.

  10. Diagnosing and ranking retinopathy disease level using diabetic fundus image recuperation approach.

    Science.gov (United States)

    Somasundaram, K; Rajendran, P Alli

    2015-01-01

    Retinal fundus images are widely used in diagnosing different types of eye diseases. The existing methods such as Feature Based Macular Edema Detection (FMED) and Optimally Adjusted Morphological Operator (OAMO) effectively detected the presence of exudation in fundus images and identified the true positive ratio of exudates detection, respectively. These mechanically detected exudates did not include more detailed feature selection technique to the system for detection of diabetic retinopathy. To categorize the exudates, Diabetic Fundus Image Recuperation (DFIR) method based on sliding window approach is developed in this work to select the features of optic cup in digital retinal fundus images. The DFIR feature selection uses collection of sliding windows with varying range to obtain the features based on the histogram value using Group Sparsity Nonoverlapping Function. Using support vector model in the second phase, the DFIR method based on Spiral Basis Function effectively ranks the diabetic retinopathy disease level. The ranking of disease level on each candidate set provides a much promising result for developing practically automated and assisted diabetic retinopathy diagnosis system. Experimental work on digital fundus images using the DFIR method performs research on the factors such as sensitivity, ranking efficiency, and feature selection time.

  11. Unique identification code for medical fundus images using blood vessel pattern for tele-ophthalmology applications.

    Science.gov (United States)

    Singh, Anushikha; Dutta, Malay Kishore; Sharma, Dilip Kumar

    2016-10-01

    Identification of fundus images during transmission and storage in database for tele-ophthalmology applications is an important issue in modern era. The proposed work presents a novel accurate method for generation of unique identification code for identification of fundus images for tele-ophthalmology applications and storage in databases. Unlike existing methods of steganography and watermarking, this method does not tamper the medical image as nothing is embedded in this approach and there is no loss of medical information. Strategic combination of unique blood vessel pattern and patient ID is considered for generation of unique identification code for the digital fundus images. Segmented blood vessel pattern near the optic disc is strategically combined with patient ID for generation of a unique identification code for the image. The proposed method of medical image identification is tested on the publically available DRIVE and MESSIDOR database of fundus image and results are encouraging. Experimental results indicate the uniqueness of identification code and lossless recovery of patient identity from unique identification code for integrity verification of fundus images. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  12. The grey fovea sign of macular oedema or subfoveal fluid on non-stereoscopic fundus photographs

    DEFF Research Database (Denmark)

    Hasler, Pascal W; Soliman, Wael; Sander, Birgit

    2017-01-01

    PURPOSE: To describe the grey fovea sign of fovea-involving macular oedema or subretinal fluid accumulation in red-free fundus photography. METHODS: A test set of 91 digital fundus photographs of good quality from 100 consecutive eyes in 72 patients with diabetic retinopathy or central serous...... chorioretinopathy was composed by one of the investigators and evaluated by four masked observers. The photographs were graded as to whether a normal dark fovea was present or absent. The reference method was foveal thickness measurement using optical coherence tomography (OCT). RESULTS: Eyes graded as having...... a grey fovea on fundus photographs (n = 67) had a median foveal thickness of 279 μm (interquartile range 130 μm), whereas eyes graded as having a normal dark fovea (n = 24) had a median foveal thickness of 238 μm (interquartile range 44.5 μm, p = 0.025). CONCLUSION: The absence of a dark fovea on red...

  13. Fundus autofluorescence and optical coherence tomography findings in thiamine responsive megaloblastic anemia.

    Science.gov (United States)

    Ach, Thomas; Kardorff, Rüdiger; Rohrschneider, Klaus

    2015-01-01

    To report ophthalmologic fundus autofluorescence and spectral domain optical coherence tomography findings in a patient with thiamine responsive megaloblastic anemia (TRMA). A 13-year-old girl with genetically proven TRMA was ophthalmologically (visual acuity, funduscopy, perimetry, electroretinogram) followed up over >5 years. Fundus imaging also included autofluorescence and spectral domain optical coherence tomography. During a 5-year follow-up, visual acuity and visual field decreased, despite a special TRMA diet. Funduscopy revealed bull's eye appearance, whereas fundus autofluorescence showed central and peripheral hyperfluorescence and perifoveal hypofluorescence. Spectral domain optical coherence tomography revealed affected inner segment ellipsoid band and irregularities in the retinal pigment epithelium and choroidea. Autofluorescence and spectral domain optical coherence tomography findings in a patient with TRMA show retinitis pigmentosa-like retina, retinal pigment epithelium, and choroid alterations. These findings might progress even under special TRMA diet, indispensable to life. Ophthalmologist should consider TRMA in patients with deafness and ophthalmologic disorders.

  14. PATTERNS OF FUNDUS AUTOFLUORESCENCE DEFECTS IN NEOVASCULAR AGE-RELATED MACULAR DEGENERATION SUBTYPES.

    Science.gov (United States)

    Ozkok, Ahmet; Sigford, Douglas K; Tezel, Tongalp H

    2016-11-01

    To test define characteristic fundus autofluorescence patterns of different exudative age-related macular degeneration subtypes. Cross-sectional study. Fifty-two patients with choroidal neovascularization because of three different neovascular age-related macular degeneration subtypes were included in the study. Macular and peripheral fundus autofluorescence patterns of study subjects were compared in a masked fashion. Fundus autofluorescence patterns of all three neovascular age-related macular degeneration subtypes revealed similar patterns. However, peripapillary hypo-autofluorescence was more common among patients with polypoidal choroidal vasculopathy (88.2%) compared with patients with retinal angiomatous proliferation (12.5%) and patients without retinal angiomatous proliferation and polypoidal choroidal vasculopathy (21.1%) (P autofluorescence defects in neovascular age-related macular degeneration maybe suggestive of polypoidal choroidal vasculopathy as a variant of neovascular age-related macular degeneration.

  15. [Follow-up on MEWDS by fundus perimetry and multifocal ERG with the SLO].

    Science.gov (United States)

    Bültmann, S; Martin, M; Rohrschneider, K

    2002-09-01

    Most conventional techniques for examination such as perimetry or ERG may not be sensitive enough to detect functional alterations due to MEWDS precisely. We report on a follow-up performed by fundus perimetry and the new technique of multifocal ERG using the scanning laser ophthalmoscope. A 24-year-old female patient (VA 0.2/0.8) was followed up for 7 weeks with these techniques as well as Octopus perimetry, fluorescence angiography, Ganzfeld ERG and biomicroscopy. Multifocal ERG stimulation (mfERG, Retiscan) was performed with the SLO. Visual acuity improved from 0.2 to 0.8 and the central relative scotoma disappeared while a relevant increase of P1-wave amplitudes in mfERG could be observed. Combining objective measurements from the fundus controlled SLO-mfERG and results from fundus perimetry enable good correlation of morphology and results, even for minor alterations of the macula only accessible by few established clinical examinations.

  16. Classification of diabetic retinopathy using fractal dimension analysis of eye fundus image

    Science.gov (United States)

    Safitri, Diah Wahyu; Juniati, Dwi

    2017-08-01

    Diabetes Mellitus (DM) is a metabolic disorder when pancreas produce inadequate insulin or a condition when body resist insulin action, so the blood glucose level is high. One of the most common complications of diabetes mellitus is diabetic retinopathy which can lead to a vision problem. Diabetic retinopathy can be recognized by an abnormality in eye fundus. Those abnormalities are characterized by microaneurysms, hemorrhage, hard exudate, cotton wool spots, and venous's changes. The diabetic retinopathy is classified depends on the conditions of abnormality in eye fundus, that is grade 1 if there is a microaneurysm only in the eye fundus; grade 2, if there are a microaneurysm and a hemorrhage in eye fundus; and grade 3: if there are microaneurysm, hemorrhage, and neovascularization in the eye fundus. This study proposed a method and a process of eye fundus image to classify of diabetic retinopathy using fractal analysis and K-Nearest Neighbor (KNN). The first phase was image segmentation process using green channel, CLAHE, morphological opening, matched filter, masking, and morphological opening binary image. After segmentation process, its fractal dimension was calculated using box-counting method and the values of fractal dimension were analyzed to make a classification of diabetic retinopathy. Tests carried out by used k-fold cross validation method with k=5. In each test used 10 different grade K of KNN. The accuracy of the result of this method is 89,17% with K=3 or K=4, it was the best results than others K value. Based on this results, it can be concluded that the classification of diabetic retinopathy using fractal analysis and KNN had a good performance.

  17. Factores asociados a la adherencia al tratamiento de Malaria en Piura y Tumbes - Perú

    OpenAIRE

    Llanos-Zavalaga, Fernando; Facultad de Salud Pública y Administración, Universidad Peruana Cayetano Heredia; Cotrina R, Armando; Facultad de Medicina, Universidad Peruana Cayetano Heredia; Campana S, Pilar; Facultad de Salud Pública y Administración, Universidad Peruana Cayetano Heredia

    2001-01-01

    La Organización Mundial de Salud considera al tratamiento temprano y adecuado como parte fundamental del programa mundial de control de la malaria. Un problema asociado a esta estrategia es la resistencia, especialmente de P. falciparum a las drogas antimaláricas. Objetivo: Determinar los factores sociales, culturales y de los servicios de salud asociados a la adherencia al tratamiento de malaria desde la perspectiva del usuario y del prestador, en poblados de los departamentos de Piura y Tum...

  18. Staphylococcus aureus resistente a meticilina asociado a la comunidad: aspectos epidemiológicos y moleculares

    Directory of Open Access Journals (Sweden)

    Daniel Angel Luján Roca

    2013-01-01

    Full Text Available El Staphylococcus aureus resistente a meticilina asociado a la comunidad (SARM-AC está ampliamente diseminado en el mundo. Es epidémico en algunos países y posee dos marcadores moleculares característicos: el SCCmec IV y la leucocidina de Panton-Valentine, ambos escasamente encontrados en el SARM asociado a la asistencia médica.

  19. Factores de riesgo asociados al suicidio e intento de suicidio

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    Rafael Tuesca Molina

    2003-01-01

    Full Text Available Objetivo: Identificar los factores de riesgos asociados en la población de suicidas (consumados y no consumados en Barranquilla (Colombia durante 1999-2000. Participantes y Métodos: Estudio de casos y controles incidentes. 60 casos y 56 controles no apareados. Los casos: suicidios, proceden del registro departamental de necropsia del Instituto de Medicina Legal y Ciencias Forenses y los intentos de suicidio proceden de dos hospitales de referencia del área metropolitana de la ciudad: Universitario de Barranquilla y Metropolitano. Los controles corresponden a población general y a personas que acudieron a estos hospitales al servicio de consulta externa, exceptuando consultantes a los servicios de psiquiatría y psicología. Se administró una encuesta estructurada de administración directa para identificar características sociodemográficas, trastornos del comportamiento y patología psiquiátrica. A fin de establecer la veracidad de la información de los familiares de los suicidas, se les aplicó otro instrumento denominado autopsia o necropsia psicológica, que permitió determinar y confirmar trastornos de la conducta y patología psiquiátrica. Mediciones y Resultados: Los trastornos del comportamiento asociado a los casos fue la ansiedad (OR= 7,33; p=0,00 y el temperamento explosivo (OR=3,48; p=0,00. La depresión como trastorno de tipo psiquiátrico afectó de manera importante los casos (89,8%, siendo éste un factor de riesgo significativo (OR=18,16 p=0,00. El evento de haber estado hospitalizado y padecer una enfermedad crónica se encuentra relacionado con la conducta suicida (OR= 2,81; p=0,00 y OR=8,31; p=0,00, respectivamente. Conclusiones: La ansiedad, la depresión, la presencia de enfermedades crónicas y la hospitalización son factores de riesgo del suicidio en Barranquilla

  20. Optic disc boundary segmentation from diffeomorphic demons registration of monocular fundus image sequences versus 3D visualization of stereo fundus image pairs for automated early stage glaucoma assessment

    Science.gov (United States)

    Gatti, Vijay; Hill, Jason; Mitra, Sunanda; Nutter, Brian

    2014-03-01

    Despite the current availability in resource-rich regions of advanced technologies in scanning and 3-D imaging in current ophthalmology practice, world-wide screening tests for early detection and progression of glaucoma still consist of a variety of simple tools, including fundus image-based parameters such as CDR (cup to disc diameter ratio) and CAR (cup to disc area ratio), especially in resource -poor regions. Reliable automated computation of the relevant parameters from fundus image sequences requires robust non-rigid registration and segmentation techniques. Recent research work demonstrated that proper non-rigid registration of multi-view monocular fundus image sequences could result in acceptable segmentation of cup boundaries for automated computation of CAR and CDR. This research work introduces a composite diffeomorphic demons registration algorithm for segmentation of cup boundaries from a sequence of monocular images and compares the resulting CAR and CDR values with those computed manually by experts and from 3-D visualization of stereo pairs. Our preliminary results show that the automated computation of CDR and CAR from composite diffeomorphic segmentation of monocular image sequences yield values comparable with those from the other two techniques and thus may provide global healthcare with a cost-effective yet accurate tool for management of glaucoma in its early stage.

  1. Factores asociados a la convivencia escolar en adolescentes

    Directory of Open Access Journals (Sweden)

    Clara López de Mesa-Melo

    2013-12-01

    Full Text Available El artículo presenta los resultados de una investigación sobre las condiciones y factores asociados a la convivencia escolar. El objetivo del estudio fue evaluar la convivencia escolar, mediante un estudio descriptivo y transversal en 9 instituciones educativas de 5 municipios de Cundinamarca, Colombia, en el año 2011. Participaron 1091 estudiantes y 101 profesores, los instrumentos utilizados incluyeron variables como clima escolar, agresión, factores de apoyo y riesgo, autoestima, funcionalidad familiar y bienestar subjetivo. Mediante el Modelo educativo Precede Proceed se elaboró el diagnóstico sobre convivencia escolar. Los estudiantes afirmaron que existe un clima escolar poco satisfactorio, conductas agresivas (verbales y físicas, destrozo de materiales, aislamiento social y acoso sexual. La solución de conflictos es regular y las formas de abordarlos. Los conflictos se presentan por estudiantes problemáticos, falta de respeto, disciplina e intolerancia de profesores. El aula de clase es el lugar donde se produce con mayor frecuencia las agresiones; en la solución de los conflictos intervienen los amigos y la familia. Los profesores manifestaron que los estudiantes son vulnerables a las drogas y el alcohol y no se refleja el apoyo de los padres. La violencia es independiente del tipo de establecimiento, edad, estrato y procedencia familiar (nuclear o no nuclear. Los profesores tienen alta autoestima, funcionalidad familiar y bienestar subjetivo, diferente de los estudiantes.

  2. Prevalencia de anemia y factores asociados en adultos mayores peruanos

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    Carolina Tarqui-Mamani

    Full Text Available Objetivos. Determinar la prevalencia de anemia y factores asociados en los adultos mayores del Perú. Materiales y métodos. Se realizó un estudio transversal durante el año 2011. El muestreo fue probabilístico, estratificado y multietápico. La muestra de viviendas fue 5792 y se incluyó 2172 adultos mayores. Se definió anemia como hemoglobina 23 a 80 años (OR 2,1; IC 95%: 1,4-3,0 y la delgadez (OR 1,7; IC 95%:1,2-2,3 se asociaron con la anemia. Los departamentos con mayor prevalencia de anemia fueron Ayacucho (57,6%, Ancash (40,1%, Lambayeque (37,7% y Apurímac (36,9%. Conclusiones. Aproximadamente la cuarta parte de los adultos mayores tuvieron anemia, siendo más predominante en los analfabetos, procedentes de áreas rurales y pobres. La mayor edad y la delgadez se asocian con la presencia de anemia en los adultos mayores peruanos

  3. Factores asociados a la no adherencia al tratamiento anti tuberculosis

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    Laura Inés Plata-Casas

    2015-12-01

    Full Text Available Objetivo: describir los factores de riesgo asociados a la no adherencia al tratamiento en los pacientes adscritos al programa de tuberculosis en el Municipio de Villavicencio, cohorte 2012. Materiales y Métodos: se ha realizado un estudio descriptivo de corte transversal con enfoque cuantitativo. Se obtuvieron datos de caracterización sociodemográfica sobre factores de riesgo de personas que abandonaron el tratamiento para la enfermedad- cohorte 2012- mediante la aplicación de un instrumento diseñado por el investigador y revisado por expertos. Los datos fueron tabulados y analizados mediante la herramienta Microsoft Excel® 2007 y Epi-info 7.0. Resultados: el 75% de los pacientes pertenecen al género masculino; el promedio de edad es de 30 años, el 63% pertenecen al régimen subsidiado de salud. Las principales causas de abandono fueron: efectos adversos a los medicamentos (58%, inadecuada atención del personal de salud (43%, dificultad de acceso al servicio (32%. Los factores sociales encontrados fueron hacinamiento 67% y desempleo 62%. Conclusiones: algunos factores no modificables como la edad y el género, así como factores modificables como estilos de vida inadecuados y efectos adversos; cuyo control mejoraría el cumplimiento; contribuyen al abandono del tratamiento. Las variables psicológicas y sociales deben ser evaluadas para que se conviertan en predictores de probables abandonos o irregularidades en el tratamiento antituberculoso.

  4. Differential gene expression in the murine gastric fundus lacking interstitial cells of Cajal

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    Ward Sean M

    2003-06-01

    Full Text Available Abstract Background The muscle layers of murine gastric fundus have no interstitial cells of Cajal at the level of the myenteric plexus and only possess intramuscular interstitial cells and this tissue does not generate electric slow waves. The absence of intramuscular interstitial cells in W/WV mutants provides a unique opportunity to study the molecular changes that are associated with the loss of these intercalating cells. Method The gene expression profile of the gastric fundus of wild type and W/WV mice was assayed by murine microarray analysis displaying a total of 8734 elements. Queried genes from the microarray analysis were confirmed by semi-quantitative reverse transcription-polymerase chain reaction. Results Twenty-one genes were differentially expressed in wild type and W/WV mice. Eleven transcripts had 2.0–2.5 fold higher mRNA expression in W/WV gastric fundus when compared to wild type tissues. Ten transcripts had 2.1–3.9 fold lower expression in W/WV mutants in comparison with wild type animals. None of these genes have ever been implicated in any bowel motility function. Conclusions These data provides evidence that several important genes have significantly changed in the murine fundus of W/WV mutants that lack intramuscular interstitial cells of Cajal and have reduced enteric motor neurotransmission.

  5. Hypertensive retinopathy identification through retinal fundus image using backpropagation neural network

    Science.gov (United States)

    Syahputra, M. F.; Amalia, C.; Rahmat, R. F.; Abdullah, D.; Napitupulu, D.; Setiawan, M. I.; Albra, W.; Nurdin; Andayani, U.

    2018-03-01

    Hypertension or high blood pressure can cause damage of blood vessels in the retina of eye called hypertensive retinopathy (HR). In the event Hypertension, it will cause swelling blood vessels and a decrese in retina performance. To detect HR in patients body, it is usually performed through physical examination of opthalmoscope which is still conducted manually by an ophthalmologist. Certainly, in such a manual manner, takes a ong time for a doctor to detetct HR on aa patient based on retina fundus iamge. To overcome ths problem, a method is needed to identify the image of retinal fundus automatically. In this research, backpropagation neural network was used as a method for retinal fundus identification. The steps performed prior to identification were pre-processing (green channel, contrast limited adapative histogram qualization (CLAHE), morphological close, background exclusion, thresholding and connected component analysis), feature extraction using zoning. The results show that the proposed method is able to identify retinal fundus with an accuracy of 95% with maximum epoch of 1500.

  6. Correlation between Spectral Optical Coherence Tomography and Fundus Autofluorescence at the margins of Geographic Atrophy

    Science.gov (United States)

    Brar, Manpreet; Kozak, Igor; Cheng, Lingyun; Bartsch, Dirk-Uwe G.; Yuson, Ritchie; Nigam, Nitin; Oster, Stephen F.; Mojana, Francesca; Freeman, William R.

    2009-01-01

    Purpose We studied the appearance of margins of Geographic atrophy in high- resolution optical coherence tomography (OCT) images and correlate those changes with fundus autofluorescence imaging. Design Retrospective observational case study. Methods Patients with geographic atrophy secondary to dry age related macular degeneration (ARMD) were assessed by means of Spectral Domain OCT (Spectralis HRA/OCT; Heidelberg Engineering, Heidelberg, Germany or OTI, Inc, Toronto, Canada) as well as Autofluoresence Imaging (HRA or Spectralis Heidelberg Engineering, Heidelberg, Germany): The outer retinal layer alterations were analyzed in the junctional zone between normal retina and atrophic retina, and correlated with corresponding fundus autofluorescence. Results 23 eyes of 16 patients aged between 62 years to 96 years were examined. There was a significant association between OCT findings and the fundus autofluorescence findings(r=0.67, pautofluorescence; Smooth margins on OCT correspond significantly to normal fundus autofluorescence. (Kappa-0.7348, pautofluorescence; secondary to increased lipofuscin may together serve as determinants of progression of geographic atrophy. PMID:19541290

  7. Fundus autofluorescence and optical coherence tomographic findings in acute zonal occult outer retinopathy.

    Science.gov (United States)

    Fujiwara, Takamitsu; Imamura, Yutaka; Giovinazzo, Vincent J; Spaide, Richard F

    2010-09-01

    The purpose of this study was to investigate the fundus autofluorescence and optical coherence tomography findings in eyes with acute zonal occult outer retinopathy (AZOOR). A retrospective observational case series of the fundus autofluorescence and spectral domain optical coherence tomography in a series of patients with AZOOR. There were 19 eyes of 11 patients (10 women), who had a mean age of 49.1 +/- 13.9 years. Fundus autofluorescence abnormalities were seen in 17 of the 19 eyes, were more common in the peripapillary area, and were smaller in extent than the optical coherence tomography abnormalities. Nine eyes showed progression of hypoautofluorescence area during the mean follow-up of 69.7 months. The mean thickness of the photoreceptor layer at fovea was 177 microm in eyes with AZOOR, which was significantly thinner than controls (193 microm, P = 0.049). Abnormal retinal laminations were found in 12 eyes and were located over areas of loss of the photoreceptors. The subfoveal choroidal thickness was 243 microm, which is normal. Fundus autofluorescence abnormalities in AZOOR showed distinct patterns of retinal pigment epithelial involvement, which may be progressive. Thinning of photoreceptor cell layer with loss of the outer segments and abnormal inner retinal lamination in the context of a normal choroid are commonly found in AZOOR.

  8. [Fundus autofluorescence in patients with inherited retinal diseases : Patterns of fluorescence at two different wavelengths.

    NARCIS (Netherlands)

    Theelen, T.; Boon, C.J.F.; Klevering, B.J.; Hoyng, C.B.

    2008-01-01

    BACKGROUND: Fundus autofluorescence (FAF) may be excited and measured at different wavelengths. In the present study we compared short wavelength and near-infrared FAF patterns of retinal dystrophies. METHODS: We analysed both eyes of 108 patients with diverse retinal dystrophies. Besides colour

  9. Fundus autofluorescence and optical coherence tomography of congenital grouped albinotic spots.

    Science.gov (United States)

    Kim, David Y; Hwang, John C; Moore, Anthony T; Bird, Alan C; Tsang, Stephen H

    2010-09-01

    The purpose of this study was to describe the findings of fundus autofluores-cence (FAF) and optical coherence tomography in a series of patients with congenital grouped albinotic spots. Three eyes of three patients with congenital grouped albinotic spots were evaluated with FAF and optical coherence tomography imaging to evaluate the nature of the albinotic spots. In all three eyes with congenital grouped albinotic spots, FAF imaging showed autofluorescent spots corresponding to the albinotic spots seen on stereo biomicroscopy. One eye also had additional spots detected on FAF imaging that were not visible on stereo biomicroscopy or color fundus photographs. Fundus autofluorescence imaging of the spots showed decreased general autofluorescence and decreased peripheral autofluorescence surrounding central areas of retained or increased autofluorescence. Optical coherence tomography showed a disruption in signal from the hyperreflective layer corresponding to the inner and outer segment junction and increased signal backscattering from the choroid in the area of the spots. Fluorescein angiography showed early and stable hyperfluorescence of the spots without leakage. In this case series, FAF showed decreased autofluorescence of the spots consistent with focal retinal pigment epithelium atrophy or abnormal material blocking normal autofluorescence and areas of increased autofluorescence suggesting retinal pigment epithelium dysfunction. The findings of optical coherence tomography and fluorescein angiography suggest photoreceptor and retinal pigment epithelium layer abnormalities. Fundus autofluorescence and optical coherence tomography are useful noninvasive diagnostic adjuncts that can aid in the diagnosis of congenital grouped albinotic spots, help determine extent of disease, and contribute to our understanding of its pathophysiology.

  10. Quality Enhancement and Nerve Fibre Layer Artefacts Removal in Retina Fundus Images by Off Axis Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Giancardo, Luca [ORNL; Meriaudeau, Fabrice [ORNL; Karnowski, Thomas Paul [ORNL; Li, Yaquin [University of Tennessee, Knoxville (UTK); Tobin Jr, Kenneth William [ORNL; Chaum, Edward [University of Tennessee, Knoxville (UTK)

    2011-01-01

    Retinal fundus images acquired with non-mydriatic digital fundus cameras are a versatile tool for the diagnosis of various retinal diseases. Because of the ease of use of newer camera models and their relative low cost, these cameras are employed worldwide by retina specialists to diagnose diabetic retinopathy and other degenerative diseases. Even with relative ease of use, the images produced by these systems sometimes suffer from reflectance artefacts mainly due to the nerve fibre layer (NFL) or other camera lens related reflections. We propose a technique that employs multiple fundus images acquired from the same patient to obtain a single higher quality image without these reflectance artefacts. The removal of bright artefacts, and particularly of NFL reflectance, can have great benefits for the reduction of false positives in the detection of retinal lesions such as exudate, drusens and cotton wool spots by automatic systems or manual inspection. If enough redundant information is provided by the multiple images, this technique also compensates for a suboptimal illumination. The fundus images are acquired in straightforward but unorthodox manner, i.e. the stare point of the patient is changed between each shot but the camera is kept fixed. Between each shot, the apparent shape and position of all the retinal structures that do not exhibit isotropic reflectance (e.g. bright artefacts) change. This physical effect is exploited by our algorithm in order to extract the pixels belonging to the inner layers of the retina, hence obtaining a single artefacts-free image.

  11. Retinopathy online challenge: automatic detection of microaneurysms in digital color fundus photographs.

    NARCIS (Netherlands)

    Niemeijer, M.; Ginneken, B. van; Cree, M.J.; Mizutani, A.; Quellec, G.; Sanchez, C.I.; Zhang, B.; Hornero, R.; Lamard, M.; Muramatsu, C.; Wu, X.; Cazuguel, G.; You, J.; Mayo, A.; Li, Q.; Hatanaka, Y.; Cochener, B.; Roux, C.; Karray, F.; Garcia, M.; Fujita, H.; Abramoff, M.D.

    2010-01-01

    The detection of microaneurysms in digital color fundus photographs is a critical first step in automated screening for diabetic retinopathy (DR), a common complication of diabetes. To accomplish this detection numerous methods have been published in the past but none of these was compared with each

  12. Automatic Drusen Quantification and Risk Assessment of Age-related Macular Degeneration on Color Fundus Images

    NARCIS (Netherlands)

    Grinsven, M.J.J.P. van; Lechanteur, Y.T.E.; Ven, J.P.H. van de; Ginneken, B. van; Hoyng, C.B.; Theelen, T.; Sanchez, C.I.

    2013-01-01

    PURPOSE: To evaluate a machine learning algorithm that allows for computer aided diagnosis (CAD) of non-advanced age-related macular degeneration (AMD) by providing an accurate detection and quantification of drusen location, area and size. METHODS: Color fundus photographs of 407 eyes without AMD

  13. Ocular Fundus Photography as a Tool to Study Stroke and Dementia.

    Science.gov (United States)

    Cheung, Carol Y; Chen, Christopher; Wong, Tien Y

    2015-10-01

    Although cerebral small vessel disease has been linked to stroke and dementia, due to limitations of current neuroimaging technology, direct in vivo visualization of changes in the cerebral small vessels (e.g., cerebral arteriolar narrowing, tortuous microvessels, blood-brain barrier damage, capillary microaneurysms) is difficult to achieve. As the retina and the brain share similar embryological origin, anatomical features, and physiologic properties with the cerebral small vessels, the retinal vessels offer a unique and easily accessible "window" to study the correlates and consequences of cerebral small vessel diseases in vivo. The retinal microvasculature can be visualized, quantified and monitored noninvasively using ocular fundus photography. Recent clinic- and population-based studies have demonstrated a close link between retinal vascular changes seen on fundus photography and stroke and dementia, suggesting that ocular fundus photography may provide insights to the contribution of microvascular disease to stroke and dementia. In this review, we summarize current knowledge on retinal vascular changes, such as retinopathy and changes in retinal vascular measures with stroke and dementia as well as subclinical makers of cerebral small vessel disease, and discuss the possible clinical implications of these findings in neurology. Studying pathologic changes of retinal blood vessels may be useful for understanding the etiology of various cerebrovascular conditions; hence, ocular fundus photography can be potentially translated into clinical practice. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  14. Image quality characteristics of a novel colour scanning digital ophthalmoscope (SDO) compared with fundus photography.

    Science.gov (United States)

    Strauss, Rupert W; Krieglstein, Tina R; Priglinger, Siegfried G; Reis, Werner; Ulbig, Michael W; Kampik, Anselm; Neubauer, Aljoscha S

    2007-11-01

    To establish a set of quality parameters for grading image quality and apply those to evaluate the fundus image quality obtained by a new scanning digital ophthalmoscope (SDO) compared with standard slide photography. On visual analogue scales a total of eight image characteristics were defined: overall quality, contrast, colour brilliance, focus (sharpness), resolution and details, noise, artefacts and validity of clinical assessment. Grading was repeated after 4 months to assess repeatability. Fundus images of 23 patients imaged digitally by SDO and by Zeiss 450FF fundus camera using Kodak film were graded side-by-side by three graders. Lens opacity was quantified with the Interzeag Lens Opacity Meter 701. For all of the eight scales of image quality, good repeatability within the graders (mean Kendall's W 0.69) was obtained after 4 months. Inter-grader agreement ranged between 0.31 and 0.66. Despite the SDO's limited nominal image resolution of 720 x 576 pixels, the Zeiss FF 450 camera performed better in only two of the subscales - noise (p = 0.001) and artefacts (p = 0.01). Lens opacities significantly influenced only the two subscales 'resolution' and 'details', which deteriorated with increasing media opacities for both imaging systems. Distinct scales to grade image characteristics of different origin were developed and validated. Overall SDO digital imaging was found to provide fundus pictures of a similarly high level of quality as expert photography on slides.

  15. Subretinal Fibrosis in Stargardt’s Disease with Fundus Flavimaculatus and ABCA4 Gene Mutation

    Directory of Open Access Journals (Sweden)

    Settimio Rossi

    2012-12-01

    Full Text Available Purpose: To report on 4 patients affected by Stargardt’s disease (STGD with fundus flavimaculatus (FFM and ABCA4 gene mutation associated with subretinal fibrosis. Methods: Four patients with a diagnosis of STGD were clinically examined. All 4 cases underwent a full ophthalmologic evaluation, including best-corrected visual acuity measured by the Snellen visual chart, biomicroscopic examination, fundus examination, fundus photography, electroretinogram, microperimetry, optical coherence tomography and fundus autofluorescence. All patients were subsequently screened for ABCA4 gene mutations, identified by microarray genotyping and confirmed by conventional DNA sequencing of the relevant exons. Results: In all 4 patients, ophthalmologic exam showed areas of subretinal fibrosis in different retinal sectors. In only 1 case, these lesions were correlated to an ocular trauma as confirmed by biomicroscopic examination of the anterior segment that showed a nuclear cataract dislocated to the superior site and vitreous opacities along the lens capsule. The other patients reported a lifestyle characterized by competitive sport activities. The performed instrumental diagnostic investigations confirmed the diagnosis of STGD with FFM in all patients. Moreover, in all 4 affected individuals, mutations in the ABCA4 gene were found. Conclusions: Patients with the diagnosis of STGD associated with FFM can show atypical fundus findings. We report on 4 patients affected by STGD with ABCA4 gene mutation associated with subretinal fibrosis. Our findings suggest that this phenomenon can be accelerated by ocular trauma and also by ocular microtrauma caused by sport activities, highlighting that lifestyle can play a role in the onset of these lesions.

  16. Telemedicine for diabetic retinopathy screening using an ultra-widefield fundus camera

    Directory of Open Access Journals (Sweden)

    Hussain N

    2017-08-01

    Full Text Available Nazimul Hussain,1 Maryam Edraki,2 Rima Tahhan,2 Nishanth Sanalkumar,2 Sami Kenz,2 Nagwa Khalil Akasha,2 Brian Mtemererwa,2 Nahed Mohammed2 1Department of Ophthalmology, Al Zahra Hospital, Sharjah, United Arab Emirates; 2Department of Endocrinology, Al Zahra Hospital, Sharjah, United Arab Emirates Objective: Telemedicine reporting of diabetic retinopathy (DR screening using ultra-widefield (UWF fundus camera. Materials and methods: Cross-sectional study of diabetic patients who visited the endocrinology department of a private multi-specialty hospital in United Arab Emirates between April 2015 and January 2017 who underwent UWF fundus imaging. Fundus pictures are then accessed at the Retina Clinic in the Department of Ophthalmology. Primary outcome measure was incidence of any form of DR detected. The secondary outcome measure was failure to take good image and inability to grade. Results: A total of 1,024 diabetic individuals were screened for DR from April 2015 to January 2017 in the department of Endocrinology. Rate of DR was 9.27%; 165 eyes of 95 individuals were diagnosed to have some form of DR. Mild non-proliferative DR (NPDR was seen in 114 of 165 eyes (69.09%, moderate NPDR in 32 eyes (19.39%, severe NPDR in six eyes (3.64%, and proliferative DR (PDR in 13 eyes (7.88%. The secondary outcome measure of poor image acquisition was seen in one individual who had an image acquired in one eye that could not be graded due to bad picture quality. Conclusions: The present study has shown the effectiveness of DR screening using UWF fundus camera. It has shown the effectiveness of trained nursing personnel taking fundus images. This model can be replicated in any private multi-specialty hospital and reduce the burden of DR screening in the retina clinic and enhance early detection of treatable DR. Keywords: telemedicine, ultra-widefield camera, diabetic retinopathy screening

  17. Trastorno neurocognitivo asociado al virus de inmunodeficiencia humana

    Directory of Open Access Journals (Sweden)

    Erik Guevara-Silva

    2014-04-01

    Full Text Available El trastorno neurocognitivo asociado a VIH (TNAV es una complicación poco conocida pero de elevada prevalencia e impacto en los pacientes con VIH. El término TNAV agrupa un espectro de complicaciones progresivas del sistema nervioso central (SNC, desde un compromiso neurocognitivo asintomático y un trastorno neurocognitivo leve hasta una demencia asociada a VIH (DAV. Mientras que la incidencia de DAV ha disminuido significativamente con el tratamiento antirretroviral de gran actividad (TARGA, las formas más leves de TNAV se han incrementado. En esta revisión, describimos la nomenclatura actualizada y definiciones de caso para orientar el diagnóstico del TNAV. También, resumimos las manifestaciones clínicas, diagnóstico y recomendaciones para el tratamiento. Finalmente, mientras que el deterioro cognitivo es típicamente diagnosticado con una evaluación neuropsicológica completa, la interpretación de los resultados se basa en la comparación entre el rendimiento del paciente con valores normalizados en poblaciones ajustados culturalmente y según edad; así, los resultados de estas pruebas son válidos solo si existen datos representativos normalizados adecuadamente para un paciente. Por lo tanto, proponemos un grupo de pruebas neuropsicológicas breves validadas en nuestra población peruana, que pueden ser utilizadas para la detección temprana del TNAV no solo por los neurólogos sino también por el médico tratante del paciente con VIH o en centros de escasos recursos.

  18. DrishtiCare: a telescreening platform for diabetic retinopathy powered with fundus image analysis.

    Science.gov (United States)

    Joshi, Gopal Datt; Sivaswamy, Jayanthi

    2011-01-01

    Diabetic retinopathy is the leading cause of blindness in urban populations. Early diagnosis through regular screening and timely treatment has been shown to prevent visual loss and blindness. It is very difficult to cater to this vast set of diabetes patients, primarily because of high costs in reaching out to patients and a scarcity of skilled personnel. Telescreening offers a cost-effective solution to reach out to patients but is still inadequate due to an insufficient number of experts who serve the diabetes population. Developments toward fundus image analysis have shown promise in addressing the scarcity of skilled personnel for large-scale screening. This article aims at addressing the underlying issues in traditional telescreening to develop a solution that leverages the developments carried out in fundus image analysis. We propose a novel Web-based telescreening solution (called DrishtiCare) integrating various value-added fundus image analysis components. A Web-based platform on the software as a service (SaaS) delivery model is chosen to make the service cost-effective, easy to use, and scalable. A server-based prescreening system is employed to scrutinize the fundus images of patients and to refer them to the experts. An automatic quality assessment module ensures transfer of fundus images that meet grading standards. An easy-to-use interface, enabled with new visualization features, is designed for case examination by experts. Three local primary eye hospitals have participated and used DrishtiCare's telescreening service. A preliminary evaluation of the proposed platform is performed on a set of 119 patients, of which 23% are identified with the sight-threatening retinopathy. Currently, evaluation at a larger scale is under process, and a total of 450 patients have been enrolled. The proposed approach provides an innovative way of integrating automated fundus image analysis in the telescreening framework to address well-known challenges in large

  19. Internet y televisión educativa: Factores asociados a su uso y abuso

    Directory of Open Access Journals (Sweden)

    José Juan Machargo Díaz

    2017-09-01

    Full Text Available Este artículo presenta un análisis sobre el uso de internet y la televisión educativa en jóvenes y niños en edades comprendidas entre 7 y 17 años de edad. A partir de análisis documental desde un enfoque cualitativo tipo documental y una entrevista, se identifican variables asociadas al uso de internet y programas educativos. Conclusión: Factores asociados al uso de internet y la televisión educativa son factores personales, factores de apoyo familiar e institucional (maestro; factores actitudinales, factores sociales e impacto: positivo asociado a relaciones, aprendizaje, y negativos asociado a salud, adicciones, rendimiento académico negativo

  20. The significance of fluorescein angiography in the early diagnosis of lesions on ocular fundus at pseudoxanthoma elasticum patients.

    Science.gov (United States)

    Bogdanowski, T; Gluza, J; Rasiewicz, D

    1977-05-27

    The role of fluorescein angiography in early diagnosis of lesions on fundus of the eye at pseudoxanthoma elasticum patients has been shown. The authors show angiographic changes on the basis of three cases of pseudoxanthoma elasticum patients.

  1. EARLY SIMULTANEOUS FUNDUS AUTOFLUORESCENCE AND OPTICAL COHERENCE TOMOGRAPHY FEATURES AFTER PARS PLANA VITRECTOMY FOR PRIMARY RHEGMATOGENOUS RETINAL DETACHMENT

    NARCIS (Netherlands)

    Dellʼomo, Roberto; Mura, Marco; Lesnik Oberstein, Sarit Y.; Bijl, Heico; Tan, H. Stevie

    2012-01-01

    Purpose: To describe fundus autofluorescence and optical coherence tomography (OCT) features of the macula after pars plana vitrectomy for rhegmatogenous retinal detachment. Methods: Thirty-three eyes of 33 consecutive patients with repaired rhegmatogenous retinal detachment with or without the

  2. Enhanced depth imaging optical coherence tomography and fundus autofluorescence findings in bilateral choroidal osteoma: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Erol, Muhammet Kazim; Coban, Deniz Turgut; Ceran, Basak Bostanci; Bulut, Mehmet, E-mail: muhammetkazimerol@gmail.com [Kazim Erol. Antalya Training and Research Hospital, Ophthalmology Department, Antalya (Turkey)

    2013-11-01

    The authors present enhanced depth imaging optical coherence tomography (EDI OCT) and fundus autofluorescence (FAF) characteristics of a patient with bilateral choroidal osteoma and try to make a correlation between two imaging techniques. Two eyes of a patient with choroidal osteoma underwent complete ophthalmic examination. Enhanced depth imaging optical coherence tomography revealed a cage-like pattern, which corresponded to the calcified region of the tumor. Fundus autofluorescence imaging of the same area showed slight hyperautofluorescence. Three different reflectivity patterns in the decalcified area were defined. In the areas of subretinal fluid, outer segment elongations similar to central serous chorioretinopathy were observed. Hyperautofluorescent spots were evident in fundus autofluorescence in the same area. Calcified and decalcified portions of choroidal osteoma as well as the atrophy of choriocapillaris demonstrated different patterns with enhanced depth imaging and fundus autofluorescence imaging. Both techniques were found to be beneficial in the diagnosis and follow-up of choroidal osteoma. (author)

  3. Enhanced depth imaging optical coherence tomography and fundus autofluorescence findings in bilateral choroidal osteoma: a case report

    International Nuclear Information System (INIS)

    Erol, Muhammet Kazim; Coban, Deniz Turgut; Ceran, Basak Bostanci; Bulut, Mehmet

    2013-01-01

    The authors present enhanced depth imaging optical coherence tomography (EDI OCT) and fundus autofluorescence (FAF) characteristics of a patient with bilateral choroidal osteoma and try to make a correlation between two imaging techniques. Two eyes of a patient with choroidal osteoma underwent complete ophthalmic examination. Enhanced depth imaging optical coherence tomography revealed a cage-like pattern, which corresponded to the calcified region of the tumor. Fundus autofluorescence imaging of the same area showed slight hyperautofluorescence. Three different reflectivity patterns in the decalcified area were defined. In the areas of subretinal fluid, outer segment elongations similar to central serous chorioretinopathy were observed. Hyperautofluorescent spots were evident in fundus autofluorescence in the same area. Calcified and decalcified portions of choroidal osteoma as well as the atrophy of choriocapillaris demonstrated different patterns with enhanced depth imaging and fundus autofluorescence imaging. Both techniques were found to be beneficial in the diagnosis and follow-up of choroidal osteoma. (author)

  4. Enhanced depth imaging optical coherence tomography and fundus autofluorescence findings in bilateral choroidal osteoma: a case report

    Directory of Open Access Journals (Sweden)

    Muhammet Kazim Erol

    2013-06-01

    Full Text Available The authors present enhanced depth imaging optical coherence tomography (EDI OCT and fundus autofluorescence (FAF characteristics of a patient with bilateral choroidal osteoma and try to make a correlation between two imaging techniques. Two eyes of a patient with choroidal osteoma underwent complete ophthalmic examination. Enhanced depth imaging optical coherence tomography revealed a cage-like pattern, which corresponded to the calcified region of the tumor. Fundus autofluorescence imaging of the same area showed slight hyperautofluorescence. Three different reflectivity patterns in the decalcified area were defined. In the areas of subretinal fluid, outer segment elongations similar to central serous chorioretinopathy were observed. Hyperautofluorescent spots were evident in fundus autofluorescence in the same area. Calcified and decalcified portions of choroidal osteoma as well as the atrophy of choriocapillaris demonstrated different patterns with enhanced depth imaging and fundus autofluorescence imaging. Both techniques were found to be beneficial in the diagnosis and follow-up of choroidal osteoma.

  5. Factores asociados al maltrato del adulto mayor de Antioquia, 2012

    Directory of Open Access Journals (Sweden)

    Sara M. Cano

    2015-07-01

    Full Text Available Objetivo: determinar los factores asociados al maltrato del adulto mayor del departamento de Antioquia en el año 2012. Metodología: mediante estudio descriptivo transversal, se caracterizaron los factores demográficos, económicos y de salud mental de la población adulta mayor de Antioquia para el año 2012, con el fin de aportar al análisis de la situación de salud y condiciones de vida del adulto mayor. El estudio se basó en los resultados del instrumento aplicado por la Universidad ces a 4.215 adultos de sesenta años y más de edad, en el cual se indagó sobre percepción de maltrato, funcionamiento cognitivo, nivel de depresión, nivel de ansiedad, apoyo social, escala de recursos sociales, entre otras; los resultados se expandieron a 654.473 adultos del departamento. Resultados: el 72,8% de adultos del departamento son mujeres, 53,7% vive en Medellín, 55% tiene primaria incompleta, 72,9% pertenece a estratos socioeconómicos 1 y 2, 45,1% no registraron ingresos en el último mes, 26,3% tiene riesgo de depresión y 34,4% tiene riesgo de ansiedad, 2,5% reportó haber sufrido descuido, 5,0% necesidades afectivas ignoradas, 1,7% algún caso de agresión física, 0,4% agresión sexual y 1,3%, afirmó haber sufrido maltrato económico. Las variables estrato socioeconómico, tipo de vivienda, etnia, riesgo de depresión, riesgo de ansiedad, riesgo de deterioro cognitivo y red de apoyo fueron las que más ayudaron a explicar la presencia de maltrato. Conclusión: enfrentar este problema requiere de una atención integral a las necesidades de los adultos mayores, participación de todos los sectores de la sociedad y conciencia transgeneracional.

  6. Factores de necesidad asociados al uso adecuado del control prenatal

    Directory of Open Access Journals (Sweden)

    Clarybel Miranda Mellado

    2016-07-01

    Full Text Available Introducción: Por las implicaciones sociales de la mortalidad y morbilidad materna es importante determinar los factores de necesidad que influyen en el uso adecuado del control prenatal en gestantes de Sincelejo. Materiales y Métodos: Estudio analítico de corte transversal, que incluyó 730 gestantes, seleccionadas mediante muestreo aleatorio por conglomerados, de las comunas de la ciudad. La información fue recolectada por medio de una encuesta sociodemográfica, una ficha de uso de control prenatal y un Cuestionario para evaluar los factores de necesidad  propuestos por el Modelo de Promoción de la Salud de Nola Pender. Las gestantes fueron contactadas en sus domicilios y diligenciaron los instrumentos. Los datos fueron analizados aplicando estadística descriptiva e inferencial para determinar las asociaciones entre variables. Resultados: El 97,7% (713 de las gestantes asistía al control prenatal, con una mediana de 4 controles prenatales. Un 2,3% (17 no lo habían iniciado al momento de la encuesta y 24,4% (178 hizo uso inadecuado. El 80,7% (589 de las gestantes califican su estado de salud como bueno o muy bueno, 94,8% (692 percibieron beneficios del control prenatal. Se encontró asociación significativa entre la percepción de beneficios y el uso adecuado de control prenatal [OR=5,5 (IC 95%: 2,8 - 10,8]. Discusión y Conclusiones: La percepción que las mujeres tienen sobre los buenos resultados que reporta la asistencia al control prenatal, es el principal factor que puede explicar la adherencia al control y el cumplimiento regular de las consultas. Cómo citar este artículo: Miranda C, Castillo IY. Factores de necesidad asociados al uso adecuado del control prenatal. Rev Cuid. 2016; 7(2: 1345-51. http://dx.doi.org/10.15649/cuidarte.v7i2.340

  7. Prevalencia y factores asociados a dismenorrea en estudiantes de la Universidad del Rosario

    OpenAIRE

    Bautista-Roa, Sandra-Johana; Bernal Herrera, Raúl Andrés; Yánez Montealegre, Natalia; Zamora Miramón, Irina Paola

    2010-01-01

    Antecedentes: la dismenorrea es el dolor asociado al ciclo menstrual. Presenta una prevalencia entre el 60 y 93%. Se han descrito factores asociados como: edad de la menarquía, índice de masa corporal, ejercicio, tabaquismo, antecedente de dismenorrea materna entre otros. Materiales y Métodos: se realizó un estudio de corte transversal, basado en una encuesta anónima a 127 mujeres de la Universidad del Rosario pertenecientes a las facultades de Medicina y Psicología. Resultados: ee encontró u...

  8. MICROORGANISMOS ASOCIADOS A FRUTOS EMBOLSADOS DE GUAYABA TAIWANESA VARIEDAD TAI KUO

    OpenAIRE

    Rossy Morera-Montoya; Helga Blanco-Metzler

    2009-01-01

    El presente trabajo se efectuó con el objetivo de identificar microorganismos asociados al fruto de la guayaba en frutos embolsados de una plantación comercial en Carrillo de Poás, Alajuela, Costa Rica, durante la época seca y lluviosa del año 2007. Se realizaron aislamientos en el laboratorio para determinar la presencia y tipo de microorganismo asociado a los síntomas. Se utilizaron cuatro tipos diferentes de material para embolsar: papel encerado, tergal (bolsa de nylon), papel de director...

  9. Factores asociados a la adherencia en el tratamiento de la infección tuberculosa

    Directory of Open Access Journals (Sweden)

    Carmen R. Gallardo

    2014-01-01

    Conclusiones: La tasa de cumplimiento del TIT fue elevada entre los que iniciaron tratamiento. Casi la mitad de los contactos con IT no iniciaron tratamiento y los factores asociados fueron: edad, relación social e induración de la PT. La pauta de tratamiento se asoció con mayor cumplimiento. Debemos conocer con precisión los factores asociados a la adherencia al tratamiento de la IT en cada área de salud y actuar sobre los grupos de riesgo, y de esta manera aproximar el control global de la tuberculosis.

  10. Trans-palpebral illumination: an approach for wide-angle fundus photography without the need for pupil dilation

    OpenAIRE

    Toslak, Devrim; Thapa, Damber; Chen, Yanjun; Erol, Muhammet Kazim; Paul Chan, R. V.; Yao, Xincheng

    2016-01-01

    It is technically difficult to construct wide-angle fundus imaging devices due to the complexity of conventional transpupillary illumination and imaging mechanisms. We report here a new method, i.e., trans-palpebral illumination, for wide-angle fundus photography without the need for pupil dilation. By constructing a smartphone-based prototype imaging device, we demonstrated a 152° view in a single-shot image. The unique combination of low-cost smartphone design and automatic illumination opt...

  11. Fundus autofluorescence imaging in dry AMD: 2014 Jules Gonin lecture of the Retina Research Foundation.

    Science.gov (United States)

    Holz, Frank G; Steinberg, Julia S; Göbel, Arno; Fleckenstein, Monika; Schmitz-Valckenberg, Steffen

    2015-01-01

    Fundus autofluorescence (FAF) imaging allows for topographic mapping of intrisnic fluorophores in the retinal pigment epithelial cell monolayer, as well as mapping of other fluorophores that may occur with disease in the outer retina and the sub-neurosensory space. FAF imaging provides information not obtainable with other imaging modalities. Near-infrared fundus autofluorescence images can also be obtained in vivo, and may be largely melanin-derived. FAF imaging has been shown to be useful in a wide spectrum of macular and retinal diseases. The scope of applications now includes identification of diseased RPE in macular/retinal diseases, elucidating pathophysiological mechanisms, identification of early disease stages, refined phenotyping, identification of prognostic markers for disease progression, monitoring disease progression in the context of both natural history and interventional therapeutic studies, and objective assessment of luteal pigment distribution and density as well as RPE melanin distribution. Here, we review the use of FAF imaging in various phenotypic manifestations of dry AMD.

  12. Segmentasi Pembuluh Darah Retina Pada Citra Fundus Menggunakan Gradient Based Adaptive Thresholding Dan Region Growing

    Directory of Open Access Journals (Sweden)

    Deni Sutaji

    2016-07-01

    Full Text Available AbstrakSegmentasi pembuluh darah pada citra fundus retina menjadi hal yang substansial dalam dunia kedokteran, karena dapat digunakan untuk mendeteksi penyakit, seperti: diabetic retinopathy, hypertension, dan cardiovascular. Dokter membutuhkan waktu sekitar dua jam untuk mendeteksi pembuluh darah retina, sehingga diperlukan metode yang dapat membantu screening agar lebih cepat.Penelitian sebelumnya mampu melakukan segmentasi pembuluh darah yang sensitif terhadap variasi ukuran lebar pembuluh darah namun masih terjadi over-segmentasi pada area patologi. Oleh karena itu, penelitian ini bertujuan untuk mengembangkan metode segmentasi pembuluh darah pada citra fundus retina yang dapat mengurangi over-segmentasi pada area patologi menggunakan Gradient Based Adaptive Thresholding dan Region Growing.Metode yang diusulkan terdiri dari 3 tahap, yaitu segmentasi pembuluh darah utama, deteksi area patologi dan segmentasi pembuluh darah tipis. Tahap segmentasi pembuluh darah utama menggunakan high-pass filtering dan tophat reconstruction pada kanal hijau citra yang sudah diperbaiki kontrasnya sehingga lebih jelas perbedaan antara pembuluh darah dan background. Tahap deteksi area patologi menggunakan metode Gradient Based Adaptive Thresholding. Tahap segmentasi pembuluh darah tipis menggunakan Region Growing berdasarkan informasi label pembuluh darah utama dan label area patologi. Hasil segmentasi pembuluh darah utama dan pembuluh darah tipis kemudian digabungkan sehingga menjadi keluaran sistem berupa citra biner pembuluh darah. Berdasarkan hasil uji coba, metode ini mampu melakukan segmentasi pembuluh darah retina dengan baik pada citra fundus DRIVE, yaitu dengan akurasi rata-rata 95.25% dan nilai Area Under Curve (AUC pada kurva Relative Operating Characteristic (ROC sebesar 74.28%.                           Kata Kunci: citra fundus retina, gradient based adaptive thresholding, patologi, pembuluh darah retina, region growing

  13. Investigating the influence of chromatic aberration and optical illumination bandwidth on fundus imaging in rats

    Science.gov (United States)

    Li, Hao; Liu, Wenzhong; Zhang, Hao F.

    2015-10-01

    Rodent models are indispensable in studying various retinal diseases. Noninvasive, high-resolution retinal imaging of rodent models is highly desired for longitudinally investigating the pathogenesis and therapeutic strategies. However, due to severe aberrations, the retinal image quality in rodents can be much worse than that in humans. We numerically and experimentally investigated the influence of chromatic aberration and optical illumination bandwidth on retinal imaging. We confirmed that the rat retinal image quality decreased with increasing illumination bandwidth. We achieved the retinal image resolution of 10 μm using a 19 nm illumination bandwidth centered at 580 nm in a home-built fundus camera. Furthermore, we observed higher chromatic aberration in albino rat eyes than in pigmented rat eyes. This study provides a design guide for high-resolution fundus camera for rodents. Our method is also beneficial to dispersion compensation in multiwavelength retinal imaging applications.

  14. Automatic Segmentation of Optic Disc in Eye Fundus Images: A Survey

    OpenAIRE

    Allam, Ali; Youssif, Aliaa; Ghalwash, Atef

    2015-01-01

    Optic disc detection and segmentation is one of the key elements for automatic retinal disease screening systems. The aim of this survey paper is to review, categorize and compare the optic disc detection algorithms and methodologies, giving a description of each of them, highlighting their key points and performance measures. Accordingly, this survey firstly overviews the anatomy of the eye fundus showing its main structural components along with their properties and functions. Consequently,...

  15. Joint optic disc and cup boundary extraction from monocular fundus images.

    Science.gov (United States)

    Chakravarty, Arunava; Sivaswamy, Jayanthi

    2017-08-01

    Accurate segmentation of optic disc and cup from monocular color fundus images plays a significant role in the screening and diagnosis of glaucoma. Though optic cup is characterized by the drop in depth from the disc boundary, most existing methods segment the two structures separately and rely only on color and vessel kink based cues due to the lack of explicit depth information in color fundus images. We propose a novel boundary-based Conditional Random Field formulation that extracts both the optic disc and cup boundaries in a single optimization step. In addition to the color gradients, the proposed method explicitly models the depth which is estimated from the fundus image itself using a coupled, sparse dictionary trained on a set of image-depth map (derived from Optical Coherence Tomography) pairs. The estimated depth achieved a correlation coefficient of 0.80 with respect to the ground truth. The proposed segmentation method outperformed several state-of-the-art methods on five public datasets. The average dice coefficient was in the range of 0.87-0.97 for disc segmentation across three datasets and 0.83 for cup segmentation on the DRISHTI-GS1 test set. The method achieved a good glaucoma classification performance with an average AUC of 0.85 for five fold cross-validation on RIM-ONE v2. We propose a method to jointly segment the optic disc and cup boundaries by modeling the drop in depth between the two structures. Since our method requires a single fundus image per eye during testing it can be employed in the large-scale screening of glaucoma where expensive 3D imaging is unavailable. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Fundus autofluorescence in the diagnosis and monitoring of acute retinal necrosis

    OpenAIRE

    Ward, Tyson SJ; Reddy, Ashvini K

    2015-01-01

    Background Acute retinal necrosis (ARN), a vision threatening viral retinitis, is often diagnosed and treated based on clinical findings. These clinical features have been well characterized by various imaging modalities, but not using fundus autofluorescence (FAF), a noninvasive method of evaluating the neurosensory retina and retinal pigment epithelium (RPE) based on the detection of endogenous fluorophores. Findings A patient diagnosed with ARN was followed over a 10-month period to identi...

  17. Fundus auto fluorescence and spectral domain ocular coherence tomography in the early detection of chloroquine retinopathy

    OpenAIRE

    Megan B. Goodman; Ari Ziskind

    2015-01-01

    Purpose: To determine the sensitivity of spectral domain ocular coherence tomography (SD-OCT) and fundus auto fluorescence (FAF) images as a screening test to detect early changes in the retina prior to the onset of chloroquine retinopathy. Method: The study was conducted using patients taking chloroquine (CQ), referred by the Rheumatology Department to the Ophthalmology Department at Tygerberg Academic Hospital. Group A consisted of 59 patients on CQ for less than 5 years, and Group B co...

  18. Application of 3-Dimensional Printing Technology to Construct an Eye Model for Fundus Viewing Study

    OpenAIRE

    Xie, Ping; Hu, Zizhong; Zhang, Xiaojun; Li, Xinhua; Gao, Zhishan; Yuan, Dongqing; Liu, Qinghuai

    2014-01-01

    Objective To construct a life-sized eye model using the three-dimensional (3D) printing technology for fundus viewing study of the viewing system. Methods We devised our schematic model eye based on Navarro's eye and redesigned some parameters because of the change of the corneal material and the implantation of intraocular lenses (IOLs). Optical performance of our schematic model eye was compared with Navarro's schematic eye and other two reported physical model eyes using the ZEMAX optical ...

  19. Mechanism of resveratrol-induced relaxation of the guinea pig fundus.

    Science.gov (United States)

    Tsai, Ching-Chung; Tey, Shu-Leei; Lee, Ming-Che; Liu, Ching-Wen; Su, Yu-Tsun; Huang, Shih-Che

    2018-04-01

    Resveratrol is a polyphenolic compound that can be isolated from plants and also is a constituent of red wine. Resveratrol induces relaxation of vascular smooth muscle and may prevent cardiovascular diseases. Impaired gastric accommodation plays an important role in functional dyspepsia and fundic relaxation and is a therapeutic target of functional dyspepsia. Although drugs for fundic relaxation have been developed, these types of drugs are still rare. The purpose of this study was to investigate the relaxant effects of resveratrol in the guinea pig fundus. We studied the relaxant effects of resveratrol in the guinea pig fundus. In addition, we investigated the mechanism of resveratrol-induced relaxation on the guinea pig fundus by using tetraethylammonium (a non-selective potassium channel blocker), apamine (a selective inhibitor of the small conductance calcium-activated potassium channel), iberiotoxin (an inhibitor of large conductance calcium-activated potassium channels), glibenclamide (an ATP-sensitive potassium channel blocker), KT 5720 (a cAMP-dependent protein kinase A inhibitor), KT 5823 (a cGMP-dependent protein kinase G inhibitor), NG-nitro-L-arginine (a competitive inhibitor of nitric oxide synthase), tetrodotoxin (a selective neuronal Na + channel blocker), ω-conotoxin GVIA (a selective neuronal Ca 2+ channel blocker) and G-15 (a G-protein coupled estrogen receptor antagonist). The results of this study showed that resveratrol has potent and dose-dependent relaxant effects on the guinea pig fundic muscle. In addition, the results showed that resveratrol-induced relaxation of the guinea pig fundus occurs through nitric oxide and ATP-sensitive potassium channels. This study provides the first evidence concerning the relaxant effects of resveratrol in the guinea pig fundic muscle strips. Furthermore, resveratrol may be a potential drug to relieve gastrointestinal dyspepsia. Copyright © 2018 Elsevier GmbH. All rights reserved.

  20. Computer-aided diagnosis based on enhancement of degraded fundus photographs.

    Science.gov (United States)

    Jin, Kai; Zhou, Mei; Wang, Shaoze; Lou, Lixia; Xu, Yufeng; Ye, Juan; Qian, Dahong

    2018-05-01

    Retinal imaging is an important and effective tool for detecting retinal diseases. However, degraded images caused by the aberrations of the eye can disguise lesions, so that a diseased eye can be mistakenly diagnosed as normal. In this work, we propose a new image enhancement method to improve the quality of degraded images. A new method is used to enhance degraded-quality fundus images. In this method, the image is converted from the input RGB colour space to LAB colour space and then each normalized component is enhanced using contrast-limited adaptive histogram equalization. Human visual system (HVS)-based fundus image quality assessment, combined with diagnosis by experts, is used to evaluate the enhancement. The study included 191 degraded-quality fundus photographs of 143 subjects with optic media opacity. Objective quality assessment of image enhancement (range: 0-1) indicated that our method improved colour retinal image quality from an average of 0.0773 (variance 0.0801) to an average of 0.3973 (variance 0.0756). Following enhancement, area under curves (AUC) were 0.996 for the glaucoma classifier, 0.989 for the diabetic retinopathy (DR) classifier, 0.975 for the age-related macular degeneration (AMD) classifier and 0.979 for the other retinal diseases classifier. The relatively simple method for enhancing degraded-quality fundus images achieves superior image enhancement, as demonstrated in a qualitative HVS-based image quality assessment. This retinal image enhancement may, therefore, be employed to assist ophthalmologists in more efficient screening of retinal diseases and the development of computer-aided diagnosis. © 2017 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  1. Evaluation of an online peer fundus photograph matching program in teaching direct ophthalmoscopy to medical students.

    Science.gov (United States)

    Kwok, Jason; Liao, Walter; Baxter, Stephanie

    2017-10-01

    Direct ophthalmoscopy is an important clinical skill that is often poorly performed by medical professionals and students. This is attributable to a declining emphasis on ophthalmology in medical school. We present and evaluate a self-directed approach of teaching ophthalmoscopy to medical students that is suitable for the current medical curriculum. Prospective medical education trial. Ninety-five second-year medical students at Queen's University: 32 in the experimental group and 63 in the control group. The experimental group consisted of medical students who practised ophthalmoscopy with one another using an online peer fundus photograph matching exercise created by the Department of Ophthalmology at Queen's University. To use the program, students first examined a peer with an ophthalmoscope and then selected an online photograph of a fundus corresponding to that of the examinee. The program notifies students if a correct selection is made. To encourage use of the program, students participated in a 2-week ophthalmoscopy competition during their ophthalmology rotation. The control group consisted of students who did not participate in the learning exercise. On assessment at the end of the ophthalmology rotation, the experimental group (n = 32) was more accurate in matching fundus photographs compared with the control group (n = 63) (p = 0.02). Participants were faster at performing ophthalmoscopy at the end of the learning exercise (p peer fundus photographs in a self-directed manner appeared to increase the skill and confidence of medical students in ophthalmoscopy. Copyright © 2017 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.

  2. Centrifugal expansion of fundus autofluorescence patterns in Stargardt disease over time.

    Science.gov (United States)

    Cukras, Catherine A; Wong, Wai T; Caruso, Rafael; Cunningham, Denise; Zein, Wadih; Sieving, Paul A

    2012-02-01

    To study the longitudinal changes in autofluorescence in Stargardt disease to reveal aspects of disease progression not previously evident. Changes in autofluorescence reflect changing fluorophore compositions of lipofuscin and melanin in retinal pigment epithelial cells, which has been hypothesized to contribute to Stargardt disease pathogenesis. We examined the temporospatial patterns of fundus autofluorescence with excitation at both 488 nm (standard fundus autofluorescence) and 795 nm (near-infrared autofluorescence) in a longitudinal case series involving 8 eyes of 4 patients (range of follow-up, 11-57 months; mean, 39 months). Image processing was performed to analyze spatial and temporal cross-modality associations. Longitudinal fundus autofluorescence imaging of fleck lesions revealed hyperautofluorescent lesions that extended in a centrifugal direction from the fovea with time. Patterns of spread were nonrandom and followed a radial path that left behind a trail of diminishing autofluorescence. Longitudinal near-infrared autofluorescence imaging also demonstrated centrifugal lesion spread but with fewer hyperautofluorescent lesions, suggestive of more transient hyperautofluorescence and more rapid decay at longer wavelengths. Fundus autofluorescence and near-infrared autofluorescence abnormalities were spatially correlated with each other, and together they reflect systematic progressions in fleck distribution and fluorophore composition occurring during the natural history of the disease. Stargardt disease fleck lesions do not evolve randomly in location but instead follow consistent patterns of radial expansion and a systematic decay of autofluorescence that reflect changing lipofuscin and melanin compositions in retinal pigment epithelial cells. These progressive foveal-to-peripheral changes are helpful in elucidating molecular and cellular mechanisms underlying Stargardt disease and may constitute potential outcome measures in clinical trials.

  3. Contact-free trans-pars-planar illumination enables snapshot fundus camera for nonmydriatic wide field photography.

    Science.gov (United States)

    Wang, Benquan; Toslak, Devrim; Alam, Minhaj Nur; Chan, R V Paul; Yao, Xincheng

    2018-06-08

    In conventional fundus photography, trans-pupillary illumination delivers illuminating light to the interior of the eye through the peripheral area of the pupil, and only the central part of the pupil can be used for collecting imaging light. Therefore, the field of view of conventional fundus cameras is limited, and pupil dilation is required for evaluating the retinal periphery which is frequently affected by diabetic retinopathy (DR), retinopathy of prematurity (ROP), and other chorioretinal conditions. We report here a nonmydriatic wide field fundus camera employing trans-pars-planar illumination which delivers illuminating light through the pars plana, an area outside of the pupil. Trans-pars-planar illumination frees the entire pupil for imaging purpose only, and thus wide field fundus photography can be readily achieved with less pupil dilation. For proof-of-concept testing, using all off-the-shelf components a prototype instrument that can achieve 90° fundus view coverage in single-shot fundus images, without the need of pharmacologic pupil dilation was demonstrated.

  4. Fundus Photography in the 21st Century—A Review of Recent Technological Advances and Their Implications for Worldwide Healthcare

    Science.gov (United States)

    Panwar, Nishtha; Huang, Philemon; Lee, Jiaying; Keane, Pearse A.; Chuan, Tjin Swee; Richhariya, Ashutosh; Teoh, Stephen; Lim, Tock Han

    2016-01-01

    Abstract Background: The introduction of fundus photography has impacted retinal imaging and retinal screening programs significantly. Literature Review: Fundus cameras play a vital role in addressing the cause of preventive blindness. More attention is being turned to developing countries, where infrastructure and access to healthcare are limited. One of the major limitations for tele-ophthalmology is restricted access to the office-based fundus camera. Results: Recent advances in access to telecommunications coupled with introduction of portable cameras and smartphone-based fundus imaging systems have resulted in an exponential surge in available technologies for portable fundus photography. Retinal cameras in the near future would have to cater to these needs by featuring a low-cost, portable design with automated controls and digitalized images with Web-based transfer. Conclusions: In this review, we aim to highlight the advances of fundus photography for retinal screening as well as discuss the advantages, disadvantages, and implications of the various technologies that are currently available. PMID:26308281

  5. Optic Disc Detection from Fundus Photography via Best-Buddies Similarity

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    Kangning Hou

    2018-05-01

    Full Text Available Robust and effective optic disc (OD detection is a necessary processing step in the research work of the automatic analysis of fundus images. In this paper, we propose a novel and robust method for the automated detection of ODs from fundus photographs. It is essentially carried out by performing template matching using the Best-Buddies Similarity (BBS measure between the hand-marked OD region and the small parts of target images. For well characterizing the local spatial information of fundus images, a gradient constraint term was introduced for computing the BBS measurement. The performance of the proposed method is validated with Digital Retinal Images for Vessel Extraction (DRIVE and Standard Diabetic Retinopathy Database Calibration Level 1 (DIARETDB1 databases, and quantitative results were obtained. Success rates/error distances of 100%/10.4 pixel and of 97.7%/12.9 pixel, respectively, were achieved. The algorithm has been tested and compared with other commonly used methods, and the results show that the proposed method shows superior performance.

  6. Reliability and reproducibility of disc-foveal angle measurements by non-mydriatic fundus photography.

    Science.gov (United States)

    Le Jeune, Caroline; Chebli, Fayçal; Leon, Lorette; Anthoine, Emmanuelle; Weber, Michel; Péchereau, Alain; Lebranchu, Pierre

    2018-01-01

    Abnormal torsion could be associated with cyclovertical strabismus, but torsion measurements are not reliable in children. To assess an objective fundus torsion evaluation in a paediatric population, we used Non-Mydriatic Fundus photography (NMFP) in healthy and cyclovertical strabismus patients to evaluate the disc-foveal angle over time and observers. We used a retrospective set of NMFP including 24 A or V-pattern strabismus and 27 age-matched normal children (mean age 6.4 and 6.7 years respectively), taken during 2 distinct follow-up consultations (separated by 251 and 479 days respectively). Each disc-foveal angle measurement (from which the ocular torsion can be assessed) was performed by 5 different observers, using graphical software and based on reproducible fundus anatomical marks. Statistical analysis was performed with a multivariate ANOVA using group, time and observers as factors, in addition to intraclass coefficient correlation (ICC) to assess measurement reproducibility. A significant difference of disc-foveal angle measures was observed between groups (p0,97). Abnormal amount of objective torsion could be associated with alphabet-pattern strabismus. Disc-foveal angle evaluation by NMFP in a children population appears as a non-invasive, reliable and reproducible method.

  7. Fundus Image Features Extraction for Exudate Mining in Coordination with Content Based Image Retrieval: A Study

    Science.gov (United States)

    Gururaj, C.; Jayadevappa, D.; Tunga, Satish

    2018-06-01

    Medical field has seen a phenomenal improvement over the previous years. The invention of computers with appropriate increase in the processing and internet speed has changed the face of the medical technology. However there is still scope for improvement of the technologies in use today. One of the many such technologies of medical aid is the detection of afflictions of the eye. Although a repertoire of research has been accomplished in this field, most of them fail to address how to take the detection forward to a stage where it will be beneficial to the society at large. An automated system that can predict the current medical condition of a patient after taking the fundus image of his eye is yet to see the light of the day. Such a system is explored in this paper by summarizing a number of techniques for fundus image features extraction, predominantly hard exudate mining, coupled with Content Based Image Retrieval to develop an automation tool. The knowledge of the same would bring about worthy changes in the domain of exudates extraction of the eye. This is essential in cases where the patients may not have access to the best of technologies. This paper attempts at a comprehensive summary of the techniques for Content Based Image Retrieval (CBIR) or fundus features image extraction, and few choice methods of both, and an exploration which aims to find ways to combine these two attractive features, and combine them so that it is beneficial to all.

  8. Analysis of Fundus Photography and Fluorescein Angiography in Nonarteritic Anterior Ischemic Optic Neuropathy and Optic Neuritis.

    Science.gov (United States)

    Kim, Min Kyung; Kim, Ungsoo Samuel

    2016-08-01

    We evaluated fundus and fluorescein angiography (FAG) findings and characteristics that can help distinguish nonarteritic anterior ischemic optic neuropathy (NAION) from optic neuritis (ON). Twenty-three NAION patients and 17 ON with disc swelling patients were enrolled in this study. We performed fundus photography and FAG. The disc-swelling pattern, hyperemia grade, presence of splinter hemorrhages, cotton-wool spots, artery/vein ratio and degree of focal telangiectasia were investigated. The FAG findings for each patient were compared with respect to the following features: the pattern of disc leakage in the early phase, arteriovenous (artery/vein) transit time (second), and the presence and pattern of the filling delay. Cotton-wool spots, focal telangiectasia, and venous congestion were more common in the affected eyes of NAION patients. Upon FAG, 76.5% of the patients in the ON group exhibited normal choroidal circulation. However, 56.5% of patients in the NAION group demonstrated abnormal filling defects, such as peripapillary, generalized, or watershed zone filling delays. Fundus findings, including cotton-wool spots, focal telangiectasia, and venous congestion in the affected eye, may be clues that can be used to diagnose NAION. In addition, choroidal insufficiencies on FAG could be also helpful in differentiating NAION from ON.

  9. EVALUATION OF PATCHY ATROPHY SECONDARY TO HIGH MYOPIA BY SEMIAUTOMATED SOFTWARE FOR FUNDUS AUTOFLUORESCENCE ANALYSIS.

    Science.gov (United States)

    Miere, Alexandra; Capuano, Vittorio; Serra, Rita; Jung, Camille; Souied, Eric; Querques, Giuseppe

    2017-05-31

    To evaluate the progression of patchy atrophy in high myopia using semiautomated software for fundus autofluorescence (FAF) analysis. The medical records and multimodal imaging of 21 consecutive highly myopic patients with macular chorioretinal patchy atrophy (PA) were retrospectively analyzed. All patients underwent repeated fundus autofluorescence and spectral domain optical coherence tomography over at least 12 months. Color fundus photography was also performed in a subset of patients. Total atrophy area was measured on FAF images using Region Finder semiautomated software embedded in Spectralis (Heidelberg Engineering, Heidelberg, Germany) at baseline and during follow-up visits. Region Finder was compared with manually measured PA on FAF images. Twenty-two eyes of 21 patients (14 women, 7 men; mean age 62.8 + 13.0 years, range 32-84 years) were included. Mean PA area using Region Finder was 2.77 ± 2.91 SD mm at baseline, 3.12 ± 2.68 mm at Month 6, 3.43 ± 2.68 mm at Month 12, and 3.73 ± 2.74 mm at Month 18 (overall P autofluorescence analysis by Region Finder semiautomated software provides accurate measurements of lesion area and allows us to quantify the progression of PA in high myopia. In our series, PA enlarged significantly over at least 12 months, and its progression seemed to be related to the lesion size at baseline.

  10. Retro-mode imaging and fundus autofluorescence with scanning laser ophthalmoscope of retinal dystrophies

    Directory of Open Access Journals (Sweden)

    Maurizio Battaglia

    2012-05-01

    Full Text Available Abstract Background Retinal dystrophies display a considerably wide range of phenotypic variability, which can make diagnosis and clinical staging difficult. The aim of the study is to analyze the contribution of retro-mode imaging (RMI and fundus autofluorescence (FAF to the characterization of retinal dystrophies. Methods Eighteen consecutive patients affected by retinal dystrophies underwent a complete ophthalmological examination, including best corrected visual acuity with ETDRS charts, blue-light fundus autofluorescence, (BL-FAF, near-infrared fundus autofluorescence (NIR-FAF, and RMI. The primary outcome was the identification of abnormal patterns on RMI. The secondary outcome was the correlation with the findings on BL-FAF and NIR-FAF. Results Overall, the main feature of RMI is represented by a pseudo-3D pattern of all the lesions at the posterior pole. More specifically, any accumulation of material within the retina appears as an area of elevation of different shape and size, displaying irregular and darker borders. No precise correlations between RMI, BL-AF, and NIR-AF imaging was found. Conclusions RMI and FAF appear to be useful tools for characterizing retinal dystrophies. Non-invasive diagnostic tools may yield additional information on the clinical setting and the monitoring of the patients.

  11. [Evaluation of fundus autofluorescence in hereditary retinal diseases using Heidelberg Retina Angiograph2].

    Science.gov (United States)

    Côco, Monique; Baba, Natalia Tamie; Sallum, Juliana Maria Ferraz

    2007-01-01

    To define characteristics of the fundus autofluorescence examination, verifying usefulness in the diagnosis and care of hereditary retinal diseases. 28 patients, adults, divided equally into four groups with diagnoses of Stargardt macular dystrophy, cone dystrophy, retinitis pigmentosa and healthy volunteers for the establishment of the normality pattern. An average of nine images with the filter for fluorescein angiography was obtained for the formation of the image autofluorescence using Heidelberg Retina Angiograph2. The images of each group of patients were analyzed to verify common characteristics. The fundus autofluorescence of healthy volunteers showed the foveal area darker than the surrounding retina. The images of Stargardt macular dystrophy, in general, presented an oval central lesion, with reduced autofluorescence. The main alterations of the autofluorescence in patients with cone dystrophy were reduced foveal autofluorescence with a parafoveal ring of increased autofluorescence. In general, the images of retinitis pigmentosa showed outlying pigments with reduced autofluorescence, and of the foveal area, in some cases disorganization or reduced autofluorescence. The study showed the existence of patterns of fundus autofluorescence in the hereditary retinal diseases that allow the diagnosis and better interpretation of the pathogenesis of these diseases.

  12. FUNDUS AUTOFLUORESCENCE IN RUBELLA RETINOPATHY: Correlation With Photoreceptor Structure and Function.

    Science.gov (United States)

    Bukowska, Danuta M; Wan, Sue Ling; Chew, Avenell L; Chelva, Enid; Tang, Ivy; Mackey, David A; Chen, Fred K

    2017-01-01

    To illustrate altered fundus autofluorescence in rubella retinopathy and to investigate their relationships with photoreceptor structure and function using multimodal imaging. The authors report four cases of rubella retinopathy aged 8, 33, 42, and 50 years. All patients had dilated clinical fundus examination; wide-field color photography; blue, green, and near-infrared autofluorescence imaging and spectral domain optical coherence tomography. Two patients also underwent microperimetry and adaptive optics imaging. En face optical coherence tomography, cone mosaic, and microperimetry were coregistered with autofluorescence images. The authors explored the structure-function correlation. All four patients had a "salt-and-pepper" appearance on dilated fundus examination and wide-field color photography. There were variable-sized patches of hypoautofluorescence on both blue and near-infrared excitation in all four patients. Wave-guiding cones were visible and retinal sensitivity was intact over these regions. There was no correlation between hypoautofluorescence and regions of attenuated ellipsoid and interdigitation zones. Hyperautofluorescent lesions were also noted and some of these were pseudo-vitelliform lesions. Patchy hypoautofluorescence on near-infrared excitation can be a feature of rubella retinopathy. This may be due to abnormal melanin production or loss of melanin within retinal pigment epithelium cells harboring persistent rubella virus infection. Preservation of the ellipsoid zone, wave-guiding cones, and retinal sensitivity within hypoautofluorescent lesions suggest that these retinal pigment epithelium changes have only mild impact on photoreceptor cell function.

  13. Two-photon excited fluorescence microscopy application for ex vivo investigation of ocular fundus samples

    Science.gov (United States)

    Peters, Sven; Hammer, Martin; Schweitzer, Dietrich

    2011-07-01

    Two-photon excited fluorescence (TPEF) imaging of ocular tissue has recently become a promising tool in ophthalmology for diagnostic and research purposes. The feasibility and the advantages of TPEF imaging, namely deeper tissue penetration and improved high-resolution imaging of microstructures, have been demonstrated lately using human ocular samples. The autofluorescence properties of endogenous fluorophores in ocular fundus tissue are well known from spectrophotometric analysis. But fluorophores, especially when it comes to fluorescence lifetime, typically display a dependence of their fluorescence properties on local environmental parameters. Hence, a more detailed investigation of ocular fundus autofluorescence ideally in vivo is of utmost interest. The aim of this study is to determine space-resolved the stationary and time-resolved fluorescence properties of endogenous fluorophores in ex vivo porcine ocular fundus samples by means of two-photon excited fluorescence spectrum and lifetime imaging microscopy (FSIM/FLIM). By our first results, we characterized the autofluorescence of individual anatomical structures of porcine retina samples excited at 760 nm. The fluorescence properties of almost all investigated retinal layers are relatively homogenous. But as previously unknown, ganglion cell bodies show a significantly shorter fluorescence lifetime compared to the adjacent mueller cells. Since all retinal layers exhibit bi-exponential autofluorescence decays, we were able to achieve a more precise characterization of fluorescence properties of endogenous fluorophores compared to a present in vivo FLIM approach by confocal scanning laser ophthalmoscope (cSLO).

  14. Dense Fully Convolutional Segmentation of the Optic Disc and Cup in Colour Fundus for Glaucoma Diagnosis

    Directory of Open Access Journals (Sweden)

    Baidaa Al-Bander

    2018-03-01

    Full Text Available Glaucoma is a group of eye diseases which can cause vision loss by damaging the optic nerve. Early glaucoma detection is key to preventing vision loss yet there is a lack of noticeable early symptoms. Colour fundus photography allows the optic disc (OD to be examined to diagnose glaucoma. Typically, this is done by measuring the vertical cup-to-disc ratio (CDR; however, glaucoma is characterised by thinning of the rim asymmetrically in the inferior-superior-temporal-nasal regions in increasing order. Automatic delineation of the OD features has potential to improve glaucoma management by allowing for this asymmetry to be considered in the measurements. Here, we propose a new deep-learning-based method to segment the OD and optic cup (OC. The core of the proposed method is DenseNet with a fully-convolutional network, whose symmetric U-shaped architecture allows pixel-wise classification. The predicted OD and OC boundaries are then used to estimate the CDR on two axes for glaucoma diagnosis. We assess the proposed method’s performance using a large retinal colour fundus dataset, outperforming state-of-the-art segmentation methods. Furthermore, we generalise our method to segment four fundus datasets from different devices without further training, outperforming the state-of-the-art on two and achieving comparable results on the remaining two.

  15. Fully automatic algorithm for the analysis of vessels in the angiographic image of the eye fundus

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    Koprowski Robert

    2012-06-01

    Full Text Available Abstract Background The available scientific literature contains descriptions of manual, semi-automated and automated methods for analysing angiographic images. The presented algorithms segment vessels calculating their tortuosity or number in a given area. We describe a statistical analysis of the inclination of the vessels in the fundus as related to their distance from the center of the optic disc. Methods The paper presents an automated method for analysing vessels which are found in angiographic images of the eye using a Matlab implemented algorithm. It performs filtration and convolution operations with suggested masks. The result is an image containing information on the location of vessels and their inclination angle in relation to the center of the optic disc. This is a new approach to the analysis of vessels whose usefulness has been confirmed in the diagnosis of hypertension. Results The proposed algorithm analyzed and processed the images of the eye fundus using a classifier in the form of decision trees. It enabled the proper classification of healthy patients and those with hypertension. The result is a very good separation of healthy subjects from the hypertensive ones: sensitivity - 83%, specificity - 100%, accuracy - 96%. This confirms a practical usefulness of the proposed method. Conclusions This paper presents an algorithm for the automatic analysis of morphological parameters of the fundus vessels. Such an analysis is performed during fluorescein angiography of the eye. The presented algorithm automatically calculates the global statistical features connected with both tortuosity of vessels and their total area or their number.

  16. Multimodal segmentation of optic disc and cup from stereo fundus and SD-OCT images

    Science.gov (United States)

    Miri, Mohammad Saleh; Lee, Kyungmoo; Niemeijer, Meindert; Abràmoff, Michael D.; Kwon, Young H.; Garvin, Mona K.

    2013-03-01

    Glaucoma is one of the major causes of blindness worldwide. One important structural parameter for the diagnosis and management of glaucoma is the cup-to-disc ratio (CDR), which tends to become larger as glaucoma progresses. While approaches exist for segmenting the optic disc and cup within fundus photographs, and more recently, within spectral-domain optical coherence tomography (SD-OCT) volumes, no approaches have been reported for the simultaneous segmentation of these structures within both modalities combined. In this work, a multimodal pixel-classification approach for the segmentation of the optic disc and cup within fundus photographs and SD-OCT volumes is presented. In particular, after segmentation of other important structures (such as the retinal layers and retinal blood vessels) and fundus-to-SD-OCT image registration, features are extracted from both modalities and a k-nearest-neighbor classification approach is used to classify each pixel as cup, rim, or background. The approach is evaluated on 70 multimodal image pairs from 35 subjects in a leave-10%-out fashion (by subject). A significant improvement in classification accuracy is obtained using the multimodal approach over that obtained from the corresponding unimodal approach (97.8% versus 95.2%; p < 0:05; paired t-test).

  17. Development of a screening tool for staging of diabetic retinopathy in fundus images

    Science.gov (United States)

    Dhara, Ashis Kumar; Mukhopadhyay, Sudipta; Bency, Mayur Joseph; Rangayyan, Rangaraj M.; Bansal, Reema; Gupta, Amod

    2015-03-01

    Diabetic retinopathy is a condition of the eye of diabetic patients where the retina is damaged because of long-term diabetes. The condition deteriorates towards irreversible blindness in extreme cases of diabetic retinopathy. Hence, early detection of diabetic retinopathy is important to prevent blindness. Regular screening of fundus images of diabetic patients could be helpful in preventing blindness caused by diabetic retinopathy. In this paper, we propose techniques for staging of diabetic retinopathy in fundus images using several shape and texture features computed from detected microaneurysms, exudates, and hemorrhages. The classification accuracy is reported in terms of the area (Az) under the receiver operating characteristic curve using 200 fundus images from the MESSIDOR database. The value of Az for classifying normal images versus mild, moderate, and severe nonproliferative diabetic retinopathy (NPDR) is 0:9106. The value of Az for classification of mild NPDR versus moderate and severe NPDR is 0:8372. The Az value for classification of moderate NPDR and severe NPDR is 0:9750.

  18. Automated classification and quantitative analysis of arterial and venous vessels in fundus images

    Science.gov (United States)

    Alam, Minhaj; Son, Taeyoon; Toslak, Devrim; Lim, Jennifer I.; Yao, Xincheng

    2018-02-01

    It is known that retinopathies may affect arteries and veins differently. Therefore, reliable differentiation of arteries and veins is essential for computer-aided analysis of fundus images. The purpose of this study is to validate one automated method for robust classification of arteries and veins (A-V) in digital fundus images. We combine optical density ratio (ODR) analysis and blood vessel tracking algorithm to classify arteries and veins. A matched filtering method is used to enhance retinal blood vessels. Bottom hat filtering and global thresholding are used to segment the vessel and skeleton individual blood vessels. The vessel tracking algorithm is used to locate the optic disk and to identify source nodes of blood vessels in optic disk area. Each node can be identified as vein or artery using ODR information. Using the source nodes as starting point, the whole vessel trace is then tracked and classified as vein or artery using vessel curvature and angle information. 50 color fundus images from diabetic retinopathy patients were used to test the algorithm. Sensitivity, specificity, and accuracy metrics were measured to assess the validity of the proposed classification method compared to ground truths created by two independent observers. The algorithm demonstrated 97.52% accuracy in identifying blood vessels as vein or artery. A quantitative analysis upon A-V classification showed that average A-V ratio of width for NPDR subjects with hypertension decreased significantly (43.13%).

  19. Detection of exudates in fundus imagery using a constant false-alarm rate (CFAR) detector

    Science.gov (United States)

    Khanna, Manish; Kapoor, Elina

    2014-05-01

    Diabetic retinopathy is the leading cause of blindness in adults in the United States. The presence of exudates in fundus imagery is the early sign of diabetic retinopathy so detection of these lesions is essential in preventing further ocular damage. In this paper we present a novel technique to automatically detect exudates in fundus imagery that is robust against spatial and temporal variations of background noise. The detection threshold is adjusted dynamically, based on the local noise statics around the pixel under test in order to maintain a pre-determined, constant false alarm rate (CFAR). The CFAR detector is often used to detect bright targets in radar imagery where the background clutter can vary considerably from scene to scene and with angle to the scene. Similarly, the CFAR detector addresses the challenge of detecting exudate lesions in RGB and multispectral fundus imagery where the background clutter often exhibits variations in brightness and texture. These variations present a challenge to common, global thresholding detection algorithms and other methods. Performance of the CFAR algorithm is tested against a publicly available, annotated, diabetic retinopathy database and preliminary testing suggests that performance of the CFAR detector proves to be superior to techniques such as Otsu thresholding.

  20. Automated diagnosis of diabetic retinopathy and glaucoma using fundus and OCT images

    Directory of Open Access Journals (Sweden)

    Pachiyappan Arulmozhivarman

    2012-06-01

    Full Text Available Abstract We describe a system for the automated diagnosis of diabetic retinopathy and glaucoma using fundus and optical coherence tomography (OCT images. Automatic screening will help the doctors to quickly identify the condition of the patient in a more accurate way. The macular abnormalities caused due to diabetic retinopathy can be detected by applying morphological operations, filters and thresholds on the fundus images of the patient. Early detection of glaucoma is done by estimating the Retinal Nerve Fiber Layer (RNFL thickness from the OCT images of the patient. The RNFL thickness estimation involves the use of active contours based deformable snake algorithm for segmentation of the anterior and posterior boundaries of the retinal nerve fiber layer. The algorithm was tested on a set of 89 fundus images of which 85 were found to have at least mild retinopathy and OCT images of 31 patients out of which 13 were found to be glaucomatous. The accuracy for optical disk detection is found to be 97.75%. The proposed system therefore is accurate, reliable and robust and can be realized.

  1. Fundus Image Features Extraction for Exudate Mining in Coordination with Content Based Image Retrieval: A Study

    Science.gov (United States)

    Gururaj, C.; Jayadevappa, D.; Tunga, Satish

    2018-02-01

    Medical field has seen a phenomenal improvement over the previous years. The invention of computers with appropriate increase in the processing and internet speed has changed the face of the medical technology. However there is still scope for improvement of the technologies in use today. One of the many such technologies of medical aid is the detection of afflictions of the eye. Although a repertoire of research has been accomplished in this field, most of them fail to address how to take the detection forward to a stage where it will be beneficial to the society at large. An automated system that can predict the current medical condition of a patient after taking the fundus image of his eye is yet to see the light of the day. Such a system is explored in this paper by summarizing a number of techniques for fundus image features extraction, predominantly hard exudate mining, coupled with Content Based Image Retrieval to develop an automation tool. The knowledge of the same would bring about worthy changes in the domain of exudates extraction of the eye. This is essential in cases where the patients may not have access to the best of technologies. This paper attempts at a comprehensive summary of the techniques for Content Based Image Retrieval (CBIR) or fundus features image extraction, and few choice methods of both, and an exploration which aims to find ways to combine these two attractive features, and combine them so that it is beneficial to all.

  2. Detection of retinal nerve fiber layer defects in retinal fundus images using Gabor filtering

    Science.gov (United States)

    Hayashi, Yoshinori; Nakagawa, Toshiaki; Hatanaka, Yuji; Aoyama, Akira; Kakogawa, Masakatsu; Hara, Takeshi; Fujita, Hiroshi; Yamamoto, Tetsuya

    2007-03-01

    Retinal nerve fiber layer defect (NFLD) is one of the most important findings for the diagnosis of glaucoma reported by ophthalmologists. However, such changes could be overlooked, especially in mass screenings, because ophthalmologists have limited time to search for a number of different changes for the diagnosis of various diseases such as diabetes, hypertension and glaucoma. Therefore, the use of a computer-aided detection (CAD) system can improve the results of diagnosis. In this work, a technique for the detection of NFLDs in retinal fundus images is proposed. In the preprocessing step, blood vessels are "erased" from the original retinal fundus image by using morphological filtering. The preprocessed image is then transformed into a rectangular array. NFLD regions are observed as vertical dark bands in the transformed image. Gabor filtering is then applied to enhance the vertical dark bands. False positives (FPs) are reduced by a rule-based method which uses the information of the location and the width of each candidate region. The detected regions are back-transformed into the original configuration. In this preliminary study, 71% of NFLD regions are detected with average number of FPs of 3.2 per image. In conclusion, we have developed a technique for the detection of NFLDs in retinal fundus images. Promising results have been obtained in this initial study.

  3. Multi-frame super-resolution with quality self-assessment for retinal fundus videos.

    Science.gov (United States)

    Köhler, Thomas; Brost, Alexander; Mogalle, Katja; Zhang, Qianyi; Köhler, Christiane; Michelson, Georg; Hornegger, Joachim; Tornow, Ralf P

    2014-01-01

    This paper proposes a novel super-resolution framework to reconstruct high-resolution fundus images from multiple low-resolution video frames in retinal fundus imaging. Natural eye movements during an examination are used as a cue for super-resolution in a robust maximum a-posteriori scheme. In order to compensate heterogeneous illumination on the fundus, we integrate retrospective illumination correction for photometric registration to the underlying imaging model. Our method utilizes quality self-assessment to provide objective quality scores for reconstructed images as well as to select regularization parameters automatically. In our evaluation on real data acquired from six human subjects with a low-cost video camera, the proposed method achieved considerable enhancements of low-resolution frames and improved noise and sharpness characteristics by 74%. In terms of image analysis, we demonstrate the importance of our method for the improvement of automatic blood vessel segmentation as an example application, where the sensitivity was increased by 13% using super-resolution reconstruction.

  4. Thickness related textural properties of retinal nerve fiber layer in color fundus images.

    Science.gov (United States)

    Odstrcilik, Jan; Kolar, Radim; Tornow, Ralf-Peter; Jan, Jiri; Budai, Attila; Mayer, Markus; Vodakova, Martina; Laemmer, Robert; Lamos, Martin; Kuna, Zdenek; Gazarek, Jiri; Kubena, Tomas; Cernosek, Pavel; Ronzhina, Marina

    2014-09-01

    Images of ocular fundus are routinely utilized in ophthalmology. Since an examination using fundus camera is relatively fast and cheap procedure, it can be used as a proper diagnostic tool for screening of retinal diseases such as the glaucoma. One of the glaucoma symptoms is progressive atrophy of the retinal nerve fiber layer (RNFL) resulting in variations of the RNFL thickness. Here, we introduce a novel approach to capture these variations using computer-aided analysis of the RNFL textural appearance in standard and easily available color fundus images. The proposed method uses the features based on Gaussian Markov random fields and local binary patterns, together with various regression models for prediction of the RNFL thickness. The approach allows description of the changes in RNFL texture, directly reflecting variations in the RNFL thickness. Evaluation of the method is carried out on 16 normal ("healthy") and 8 glaucomatous eyes. We achieved significant correlation (normals: ρ=0.72±0.14; p≪0.05, glaucomatous: ρ=0.58±0.10; p≪0.05) between values of the model predicted output and the RNFL thickness measured by optical coherence tomography, which is currently regarded as a standard glaucoma assessment device. The evaluation thus revealed good applicability of the proposed approach to measure possible RNFL thinning. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  5. Efficacy of a Deep Learning System for Detecting Glaucomatous Optic Neuropathy Based on Color Fundus Photographs.

    Science.gov (United States)

    Li, Zhixi; He, Yifan; Keel, Stuart; Meng, Wei; Chang, Robert T; He, Mingguang

    2018-03-02

    To assess the performance of a deep learning algorithm for detecting referable glaucomatous optic neuropathy (GON) based on color fundus photographs. A deep learning system for the classification of GON was developed for automated classification of GON on color fundus photographs. We retrospectively included 48 116 fundus photographs for the development and validation of a deep learning algorithm. This study recruited 21 trained ophthalmologists to classify the photographs. Referable GON was defined as vertical cup-to-disc ratio of 0.7 or more and other typical changes of GON. The reference standard was made until 3 graders achieved agreement. A separate validation dataset of 8000 fully gradable fundus photographs was used to assess the performance of this algorithm. The area under receiver operator characteristic curve (AUC) with sensitivity and specificity was applied to evaluate the efficacy of the deep learning algorithm detecting referable GON. In the validation dataset, this deep learning system achieved an AUC of 0.986 with sensitivity of 95.6% and specificity of 92.0%. The most common reasons for false-negative grading (n = 87) were GON with coexisting eye conditions (n = 44 [50.6%]), including pathologic or high myopia (n = 37 [42.6%]), diabetic retinopathy (n = 4 [4.6%]), and age-related macular degeneration (n = 3 [3.4%]). The leading reason for false-positive results (n = 480) was having other eye conditions (n = 458 [95.4%]), mainly including physiologic cupping (n = 267 [55.6%]). Misclassification as false-positive results amidst a normal-appearing fundus occurred in only 22 eyes (4.6%). A deep learning system can detect referable GON with high sensitivity and specificity. Coexistence of high or pathologic myopia is the most common cause resulting in false-negative results. Physiologic cupping and pathologic myopia were the most common reasons for false-positive results. Copyright © 2018 American Academy of Ophthalmology. Published by

  6. Nematodos asociados con cultivos de arroz en Huila y Tolima

    Directory of Open Access Journals (Sweden)

    Hoyos-Carvajal Lilliana

    2010-11-01

    Full Text Available

     

    En el presente estudio son reportados géneros de nematodos asociados a cultivos de arroz en zonas productoras en Huila y Tolima bajo sistemas de inundación, los cuales incluyen Aphelenchoides, Criconema, Helicotylenchus, Hemicycliophora, Meloidogyne, Paratylenchus, Pratylenchus, Psilenchus, Tylenchorhynchus y

  7. A Homozygous Frameshift Mutation in LRAT Causes Retinitis Punctata Albescens

    NARCIS (Netherlands)

    Littink, Karin W.; van Genderen, Maria M.; van Schooneveld, Mary J.; Visser, Linda; Riemslag, Frans C. C.; Keunen, Jan E. E.; Bakker, Bjorn; Zonneveld, Marijke N.; den Hollander, Anneke I.; Cremers, Frans P. M.; van den Born, L. Ingeborgh

    2012-01-01

    Purpose: To determine the genetic defect and to describe the clinical characteristics in patients with retinitis punctata albescens (RPA) and fundus albipunctatus (FAP). Design: Case series/observational study. Participants: We included 13 patients affected by RPA or FAP. Methods: Thirteen patients

  8. A Homozygous Frameshift Mutation in LRAT Causes Retinitis Punctata Albescens.

    NARCIS (Netherlands)

    Littink, K.W.; Genderen, M.M. van; Schooneveld, M.J. van; Visser, L.; Riemslag, F.C.; Keunen, J.E.E.; Bakker, B.; Zonneveld, M.N.; Hollander, A.I. den; Cremers, F.P.M.; Born, L.I. van den

    2012-01-01

    PURPOSE: To determine the genetic defect and to describe the clinical characteristics in patients with retinitis punctata albescens (RPA) and fundus albipunctatus (FAP). DESIGN: Case series/observational study. PARTICIPANTS: We included 13 patients affected by RPA or FAP. METHODS: Thirteen patients

  9. The diagnostic accuracy of single- and five-field fundus photography in diabetic retinopathy screening by primary care physicians.

    Science.gov (United States)

    Srihatrai, Parinya; Hlowchitsieng, Thanita

    2018-01-01

    The aim is to evaluate the diagnostic accuracy of digital fundus photography in diabetic retinopathy (DR) screening at a single university hospital. This was a cross-sectional hospital-based study. One hundred and ninety-eight diabetic patients were recruited for comprehensive eye examination by two ophthalmologists. Five-field fundus photographs were taken with a digital, nonmydriatic fundus camera, and trained primary care physicians then graded the severity of DR present by single-field 45° and five-field fundus photography. Sensitivity and specificity of DR grading were reported using the findings from the ophthalmologists' examinations as a gold standard. When fundus photographs of the participants' 363 eyes were analyzed for the presence of DR, there was substantial agreement between the two primary care physicians, κ = 0.6226 for single-field and 0.6939 for five-field photograph interpretation. The sensitivity and specificity of DR detection with single-field photographs were 70.7% (95% Confidence interval [CI]; 60.2%-79.7%) and 99.3% (95% CI; 97.4%-99.9%), respectively. Sensitivity and specificity for five-field photographs were 84.5% (95% CI; 75.8%-91.1%) and 98.6% (95% CI; 96.5%-99.6%), respectively. The receiver operating characteristic was 0.85 (0.80-0.90) for single-field photographs and 0.92 (0.88-0.95) for five-field photographs. The sensitivity and specificity of fundus photographs for DR detection by primary care physicians were acceptable. Single- and five-field digital fundus photography each represent a convenient screening tool with acceptable accuracy.

  10. Color Fundus Photography versus Fluorescein Angiography in Identification of the Macular Center and Zone in Retinopathy of Prematurity

    Science.gov (United States)

    Patel, Samir N.; Klufas, Michael A.; Ryan, Michael C.; Jonas, Karyn E.; Ostmo, Susan; Martinez-Castellanos, Maria Ana; Berrocal, Audina M.; Chiang, Michael F.; Chan, R.V. Paul

    2016-01-01

    Purpose To examine the utility of fluorescein angiography (FA) in identification of the macular center and the diagnosis of zone in patients with retinopathy of prematurity (ROP). Design Validity and reliability analysis of diagnostic tools Methods 32 sets (16 color fundus photographs; 16 color fundus photographs paired with the corresponding FA) of wide-angle retinal images obtained from 16 eyes of eight infants with ROP were compiled on a secure web site. 9 ROP experts (3 pediatric ophthalmologists; 6 vitreoretinal surgeons) participated in the study. For each image set, experts identified the macular center and provided a diagnosis of zone. Main Outcome Measures (1) Sensitivity and specificity of zone diagnosis (2) “Computer facilitated diagnosis of zone,” based on precise measurement of the macular center, optic disc center, and peripheral ROP. Results Computer facilitated diagnosis of zone agreed with the expert’s diagnosis of zone in 28/45 (62%) cases using color fundus photographs and in 31/45 (69%) cases using FA. Mean (95% CI) sensitivity for detection of zone I by experts as compared to a consensus reference standard diagnosis when interpreting the color fundus images alone versus interpreting the color fundus photographs and FA was 47% (35.3% – 59.3%) and 61.1% (48.9% – 72.4%), respectively, (t(9) ≥ (2.063), p = 0.073). Conclusions There is a marginally significant difference in zone diagnosis when using color fundus photographs compared to using color fundus photographs and the corresponding fluorescein angiograms. There is inconsistency between traditional zone diagnosis (based on ophthalmoscopic exam and image review) compared to a computer-facilitated diagnosis of zone. PMID:25637180

  11. Predictors for the progression of geographic atrophy in patients with age-related macular degeneration: fundus autofluorescence study with modified fundus camera.

    Science.gov (United States)

    Jeong, Y J; Hong, I H; Chung, J K; Kim, K L; Kim, H K; Park, S P

    2014-02-01

    We examined the association between abnormal fundus autofluorescence (FAF) features on images obtained by a modified fundus camera (mFC) and geographic atrophy (GA) progression in patients with age-related macular degeneration (AMD). Serial FAF images of 131 eyes from 131 patients with GA were included in the study. All FAF images were obtained with an mFC (excitation, ∼ 500-610 nm; emission, ∼ 675-715 nm). The GA area was quantified at baseline and 1 year later using a customized segmentation program. The yearly GA enlargement rate was then calculated. Abnormal FAF patterns in the junctional zone of GA were classified as None or Minimal change, Focal, Patchy, Banded, or Diffuse according to previously published classification based on confocal scanning laser ophthalmoscopy (cSLO). The relationship between GA enlargement and abnormal FAF was evaluated. The mean rate of GA enlargement was the fastest in eyes with Diffuse pattern (1.74 mm(2) per year), followed by eyes with the Banded pattern (1.69 mm(2) per year). Binary logistic regression analysis revealed that eyes with the Banded and Diffuse pattern had significantly higher risk for GA enlargement compared with eyes with the other patterns. FAF image obtained by mFC appears to be acceptable for evaluating GA in accordance with an established cSLO-based classification. Eyes with the Banded or the Diffuse patterns of abnormal FAF at baseline indicate a high risk for GA progression. Identifying patients at high risk for GA progression using an mFC is broadly available method that can provide additional information to help predict disease course.

  12. Matching fundus photographs of classmates. An informal competition to promote learning and practice of direct ophthalmoscopy among medical students.

    Science.gov (United States)

    Krohn, Jørgen; Kjersem, Bård; Høvding, Gunnar

    2014-05-01

    To present a new approach for teaching direct ophthalmoscopy to medical students. At the University of Bergen, four consecutive classes of fourth-year medical students complete a required 9-week ophthalmology course every year. In the present project, one fundus photograph was taken of each student. The photographs were randomly numbered, printed on A4 glossy photo paper, and displayed on the classroom wall. Each student was given a form to fill in the fellow students' names matching the number of the fundus photographs. They were encouraged to practise direct ophthalmoscopy on their classmates outside formal teaching hours. At the end of the course, they returned the filled-in forms, and those with the highest number of correct matches between the fundus photographs and fellow students received a reward. Between 2011 and 2013, 239 students completed their ophthalmology course. Of these, 220 students (92%) voluntarily participated in the project. The mean score was 70% correct matches between fundus photographs and fellow students (range 7 - 100%). The students' course evaluations were overall positive. We recommend the use of peer fundus photographs in the context of a learning competition as a simple, inexpensive, and effective way to improve teaching of direct ophthalmoscopy.

  13. Automatic computer-aided diagnosis of retinal nerve fiber layer defects using fundus photographs in optic neuropathy.

    Science.gov (United States)

    Oh, Ji Eun; Yang, Hee Kyung; Kim, Kwang Gi; Hwang, Jeong-Min

    2015-05-01

    To evaluate the validity of an automatic computer-aided diagnosis (CAD) system for detection of retinal nerve fiber layer (RNFL) defects on fundus photographs of glaucomatous and nonglaucomatous optic neuropathy. We have proposed an automatic detection method for RNFL defects on fundus photographs in various cases of glaucomatous and nonglaucomatous optic neuropathy. In order to detect the vertical dark bands as candidate RNFL defects, the nonuniform illumination of the fundus image was corrected, the blood vessels were removed, and the images were converted to polar coordinates with the center of the optic disc. False positives (FPs) were reduced by using knowledge-based rules. The sensitivity and FP rates for all images were calculated. We tested 98 fundus photographs with 140 RNFL defects and 100 fundus photographs of healthy normal subjects. The proposed method achieved a sensitivity of 90% and a 0.67 FP rate per image and worked well with RNFL defects with variable depths and widths, with uniformly high detection rates regardless of the angular widths of the RNFL defects. The average detection accuracy was approximately 0.94. The overall diagnostic accuracy of the proposed algorithm for detecting RNFL defects among 98 patients and 100 healthy individuals was 86% sensitivity and 75% specificity. The proposed CAD system successfully detected RNFL defects in optic neuropathies. Thus, the proposed algorithm is useful for the detection of RNFL defects.

  14. Early simultaneous fundus autofluorescence and optical coherence tomography features after pars plana vitrectomy for primary rhegmatogenous retinal detachment.

    Science.gov (United States)

    Dell'Omo, Roberto; Mura, Marco; Lesnik Oberstein, Sarit Y; Bijl, Heico; Tan, H Stevie

    2012-04-01

    To describe fundus autofluorescence and optical coherence tomography (OCT) features of the macula after pars plana vitrectomy for rhegmatogenous retinal detachment. Thirty-three eyes of 33 consecutive patients with repaired rhegmatogenous retinal detachment with or without the involvement of the macula were prospectively investigated with simultaneous fundus autofluorescence and OCT imaging using the Spectralis HRA+OCT (Heidelberg Engineering, Heidelberg, Germany) within a few weeks after the operation. Fundus autofluorescence imaging of the macula showed lines of increased and decreased autofluorescence in 19 cases (57.6%). On OCT, these lines corresponded to the following abnormalities: outer retinal folds, inner retinal folds, and skip reflectivity abnormalities of the photoreceptor inner segment/outer segment band. Other OCT findings, not related to abnormal lines on fundus autofluorescence, consisted of disruption of photoreceptor inner segment/outer segment band and collection of intraretinal or subretinal fluid. The presence of outer retinal folds significantly related to metamorphopsia but did not relate to poor postoperative visual acuity. Partial-thickness retinal folds occur commonly after vitrectomy for rhegmatogenous retinal detachment repair and may represent an important anatomical substrate for postoperative metamorphopsia. Fundus autofluorescence and OCT are both sensitive techniques for the detection of these abnormalities.

  15. Differentiation of ocular fundus fluorophores by fluorescence lifetime imaging using multiple excitation and emission wavelengths

    Science.gov (United States)

    Hammer, M.; Schweitzer, D.; Schenke, S.; Becker, W.; Bergmann, A.

    2006-10-01

    Ocular fundus autofluorescence imaging has been introduced into clinical diagnostics recently. It is in use for the observation of the age pigment lipofuscin, a precursor of age - related macular degeneration (AMD). But other fluorophores may be of interest too: The redox pair FAD - FADH II provides information on the retinal energy metabolism, advanced glycation end products (AGE) indicate protein glycation associated with pathologic processes in diabetes as well as AMD, and alterations in the fluorescence of collagen and elastin in connective tissue give us the opportunity to observe fibrosis by fluorescence imaging. This, however, needs techniques able to differentiate particular fluorophores despite limited permissible ocular exposure as well as excitation wavelength (limited by the transmission of the human ocular lens to >400 nm). We present an ophthalmic laser scanning system (SLO), equipped with picosecond laser diodes (FWHM 100 ps, 446 nm or 468 nm respectively) and time correlated single photon counting (TCSPC) in two emission bands (500 - 560 nm and 560 - 700 nm). The decays were fitted by a bi-exponential model. Fluorescence spectra were measured by a fluorescence spectrometer fluorolog. Upon excitation at 446 nm, the fluorescence of AGE, FAD, and lipofuscin were found to peak at 503 nm, 525 nm, and 600 nm respectively. Accordingly, the statistical distribution of the fluorescence decay times was found to depend on the different excitation wavelengths and emission bands used. The use of multiple excitation and emission wavelengths in conjunction with fluorescence lifetime imaging allows us to discriminate between intrinsic fluorophores of the ocular fundus. Taken together with our knowledge on the anatomical structure of the fundus, these findings suggest an association of the short, middle and long fluorescence decay time to the retinal pigment epithelium, the retina, and connective tissue respectively.

  16. Contractile profile of esophageal and gastric fundus strips in experimental doxorubicin-induced esophageal atresia

    Directory of Open Access Journals (Sweden)

    F.A. Capeto

    2015-05-01

    Full Text Available Esophageal atresia (EA is characterized by esophageal and gastric motility changes secondary to developmental and postsurgical damage. This study evaluated the in vitro contractile profile of the distal esophagus and gastric fundus in an experimental model of EA induced by doxorubicin (DOXO. Wistar pregnant rats received DOXO 2.2 mg/kg on the 8th and 9th gestational days. On day 21.5, fetuses were collected, sacrificed, and divided into groups: control, DOXO without EA (DOXO-EA, and DOXO with EA (DOXO+EA. Strips from the distal esophagus and gastric fundus were mounted on a wire myograph and isolated organ-bath system, respectively, and subjected to increasing concentrations of carbamylcholine chloride (carbachol, CCh. The isolated esophagus was also stimulated with increasing concentrations of KCl. In esophagus, the concentration-effect curves were reduced in response to CCh in the DOXO+EA and DOXO-EA groups compared to the control group (P0.05. In response to KCl, the distal esophagus samples in the three groups were not statistically different with regard to Emax or EC50 values (P>0.05. No significant difference was noted for EC50 or Emax values in fundic strips stimulated with CCh (P>0.05. In conclusion, exposure of dams to DOXO during gestation inhibited the contractile behavior of esophageal strips from offspring in response to CCh but not KCl, regardless of EA induction. The gastric fundus of DOXO-exposed offspring did not have altered contractile responsiveness to cholinergic stimulation.

  17. Strategies of digital fundus photography for screening diabetic retinopathy in a diabetic population in urban China.

    Science.gov (United States)

    Ding, Jiyuan; Zou, Yanhong; Liu, Ningpu; Jiang, Li; Ren, Xuetao; Jia, Wei; Snellingen, Torkel; Chongsuvivatwong, Virasakdi; Liu, Xipu

    2012-12-01

    To evaluate the effect of mydriasis and different field strategies on technical failure, probability to refer diabetic retinopathy (DR, sensitivity) and probability not to refer patients without DR (specificity) of digital photography in screening with a fundus camera. A total of 531 patients with diabetes underwent fundus photography with cross-combinations of mydriasis/nonmydriasis and single-field/two-field strategies, followed by slit lamp biomicroscopic examination by a trained ophthalmologist. Fundus photographs were graded independently by another experienced ophthalmologist. Calculations were first based on cases with non-gradable images treated as being referred and then with them excluded. Percentages of DR and referable DR in this patient cohort were 22.4% and 7.7%, respectively, based on slit lamp biomicroscopic examination. Mydriasis significantly reduced the technical failure rate from 27.1% to 8.3% under a single-field strategy, and from 28.2% to 8.9% under a two-field strategy. As compared to the single-field strategy, the two-field strategy increased sensitivity from 75.6% to 87.8% without mydriasis and from 73.2% to 90.2% with mydriasis. Mydriasis increased specificity from 68.8% to 84.3% in the single-field strategy and from 64.7% to 81.6% in the two-field strategy. Had the subjects with non-gradable images been excluded, the two-field strategy without mydriasis reported sensitivity of 85.7% and specificity of 91.6%. Both mydriasis and the two-field strategy are useful in photographic screening tests. Technical failure should be taken into consideration when screening strategies for DR are determined.

  18. Detection of retinal capillary nonperfusion in fundus fluorescein angiogram of diabetic retinopathy.

    Science.gov (United States)

    Rasta, Seyed Hossein; Nikfarjam, Shima; Javadzadeh, Alireza

    2015-01-01

    Retinal capillary nonperfusion (CNP) is one of the retinal vascular diseases in diabetic retinopathy (DR) patients. As there is no comprehensive detection technique to recognize CNP areas, we proposed a different method for computing detection of ischemic retina, non-perfused (NP) regions, in fundus fluorescein angiogram (FFA) images. Whilst major vessels appear as ridges, non-perfused areas are usually observed as ponds that are surrounded by healthy capillaries in FFA images. A new technique using homomorphic filtering to correct light illumination and detect the ponds surrounded in healthy capillaries on FFA images was designed and applied on DR fundus images. These images were acquired from the diabetic patients who had referred to the Nikookari hospital and were diagnosed for diabetic retinopathy during one year. Our strategy was screening the whole image with a fixed window size, which is small enough to enclose areas with identified topographic characteristics. To discard false nominees, we also performed a thresholding operation on the screen and marked images. To validate its performance we applied our detection algorithm on 41 FFA diabetic retinopathy fundus images in which the CNP areas were manually delineated by three clinical experts. Lesions were found as smooth regions with very high uniformity, low entropy, and small intensity variations in FFA images. The results of automated detection method were compared with manually marked CNP areas so achieved sensitivity of 81%, specificity of 78%, and accuracy of 91%.The result was present as a Receiver operating character (ROC) curve, which has an area under the curve (AUC) of 0.796 with 95% confidence intervals. This technique introduced a new automated detection algorithm to recognize non-perfusion lesions on FFA. This has potential to assist detecting and managing of ischemic retina and may be incorporated into automated grading diabetic retinopathy structures.

  19. Elliptical Local Vessel Density: a Fast and Robust Quality Metric for Fundus Images

    Energy Technology Data Exchange (ETDEWEB)

    Giancardo, Luca [ORNL; Chaum, Edward [ORNL; Karnowski, Thomas Paul [ORNL; Meriaudeau, Fabrice [ORNL; Tobin Jr, Kenneth William [ORNL; Abramoff, M.D. [University of Iowa

    2008-01-01

    A great effort of the research community is geared towards the creation of an automatic screening system able to promptly detect diabetic retinopathy with the use of fundus cameras. In addition, there are some documented approaches to the problem of automatically judging the image quality. We propose a new set of features independent of Field of View or resolution to describe the morphology of the patient's vessels. Our initial results suggest that they can be used to estimate the image quality in a time one order of magnitude shorter respect to previous techniques.

  20. THE ALGORITHM OF DETERMINATION OF EYE FUNDUS VESSELS BLOOD FLOW CHARACTERISTICS ON VIDEOSEQUENCE

    Directory of Open Access Journals (Sweden)

    O. V. Nedzvedz

    2018-01-01

    Full Text Available The method of determination of the dynamic characteristics like the vessel diameter change, the linear and volume blood velocities in the vessels of the eye fundus is considered. Such characteristics allow to determine blood flow changes in the microvasculature affecting the blood flow in the brain, kidneys and coronary vessels. Developed algorithm includes four stages: the video sequence stabilization, the vessels segmentation with the help of a neural network, the determination of the instantaneous velocity in the vessels based on the optical flow and the analysis of the results.

  1. Analysis of visual appearance of retinal nerve fibers in high resolution fundus images: a study on normal subjects.

    Science.gov (United States)

    Kolar, Radim; Tornow, Ralf P; Laemmer, Robert; Odstrcilik, Jan; Mayer, Markus A; Gazarek, Jiri; Jan, Jiri; Kubena, Tomas; Cernosek, Pavel

    2013-01-01

    The retinal ganglion axons are an important part of the visual system, which can be directly observed by fundus camera. The layer they form together inside the retina is the retinal nerve fiber layer (RNFL). This paper describes results of a texture RNFL analysis in color fundus photographs and compares these results with quantitative measurement of RNFL thickness obtained from optical coherence tomography on normal subjects. It is shown that local mean value, standard deviation, and Shannon entropy extracted from the green and blue channel of fundus images are correlated with corresponding RNFL thickness. The linear correlation coefficients achieved values 0.694, 0.547, and 0.512 for respective features measured on 439 retinal positions in the peripapillary area from 23 eyes of 15 different normal subjects.

  2. Analysis of Visual Appearance of Retinal Nerve Fibers in High Resolution Fundus Images: A Study on Normal Subjects

    Directory of Open Access Journals (Sweden)

    Radim Kolar

    2013-01-01

    Full Text Available The retinal ganglion axons are an important part of the visual system, which can be directly observed by fundus camera. The layer they form together inside the retina is the retinal nerve fiber layer (RNFL. This paper describes results of a texture RNFL analysis in color fundus photographs and compares these results with quantitative measurement of RNFL thickness obtained from optical coherence tomography on normal subjects. It is shown that local mean value, standard deviation, and Shannon entropy extracted from the green and blue channel of fundus images are correlated with corresponding RNFL thickness. The linear correlation coefficients achieved values 0.694, 0.547, and 0.512 for respective features measured on 439 retinal positions in the peripapillary area from 23 eyes of 15 different normal subjects.

  3. FACTORES INDIVIDUALES, FAMILIARES Y SOCIALES ASOCIADOS AL EMBARAZO EN ADOLESCENTES EN EL CENTRO DE SALUD CARLOS SHOWING FERRARI 2014 - 2015

    OpenAIRE

    Luyo Marcellini, Delci Fiorella

    2017-01-01

    OBJETIVO: Determinar los factores individuales, familiares y sociales asociados al embarazo en adolescentes en el Centro de Salud Carlos Showing Ferrari del periodo de enero del 2014 a diciembre del 2015. METODOS Y TECNICA: El estudio fue observacional, longitudinal, retrospectivo. Con un diseño caso y control. La técnica utilizada fue el fichaje en base a la recolección de datos de fuentes secundarias. RESULTADOS: Dentro de los Factores individuales de riesgo asociados al embarazo en ...

  4. Características poblacionales y factores asociados a embarazo en mujeres adolescentes de Tuluá, Colombia

    OpenAIRE

    Sánchez Valencia,Yessica Alexandra; Mendoza Tascón,Luis Alfonso; Grisales López,Mónica Beatriz; Ceballos Molina,Leidy Yohanna; Bustamente Farfan,Johanna Catalina; Castañeda,Edgar Muriel; Chaverra,Luis Alberto; Acuña Polo,Maria Eulalia

    2013-01-01

    Antecedentes: El embarazo en adolescentes es un problema social, con múltiples determinantes asociados. Colombia tiene una tasa elevada de embarazo adolescente. Objetivo: Determinar los factores de riesgo asociados a embarazo en mujeres adolescentes. Métodos: Estudio de casos y controles, con 151 mujeres adolescentes de 19 años o menos, embarazadas, con hijos o antecedente de embarazo y 302 adolescentes controles con actividad sexual (AS) sin historia de embarazo. Las asociaciones se determin...

  5. Drusen regression is associated with local changes in fundus autofluorescence in intermediate age-related macular degeneration.

    Science.gov (United States)

    Toy, Brian C; Krishnadev, Nupura; Indaram, Maanasa; Cunningham, Denise; Cukras, Catherine A; Chew, Emily Y; Wong, Wai T

    2013-09-01

    To investigate the association of spontaneous drusen regression in intermediate age-related macular degeneration (AMD) with changes on fundus photography and fundus autofluorescence (FAF) imaging. Prospective observational case series. Fundus images from 58 eyes (in 58 patients) with intermediate AMD and large drusen were assessed over 2 years for areas of drusen regression that exceeded the area of circle C1 (diameter 125 μm; Age-Related Eye Disease Study grading protocol). Manual segmentation and computer-based image analysis were used to detect and delineate areas of drusen regression. Delineated regions were graded as to their appearance on fundus photographs and FAF images, and changes in FAF signal were graded manually and quantitated using automated image analysis. Drusen regression was detected in approximately half of study eyes using manual (48%) and computer-assisted (50%) techniques. At year-2, the clinical appearance of areas of drusen regression on fundus photography was mostly unremarkable, with a majority of eyes (71%) demonstrating no detectable clinical abnormalities, and the remainder (29%) showing minor pigmentary changes. However, drusen regression areas were associated with local changes in FAF that were significantly more prominent than changes on fundus photography. A majority of eyes (64%-66%) demonstrated a predominant decrease in overall FAF signal, while 14%-21% of eyes demonstrated a predominant increase in overall FAF signal. FAF imaging demonstrated that drusen regression in intermediate AMD was often accompanied by changes in local autofluorescence signal. Drusen regression may be associated with concurrent structural and physiologic changes in the outer retina. Published by Elsevier Inc.

  6. Análisis de los factores asociados a la calidad de vida del paciente hipertenso

    OpenAIRE

    Cristina Nolasco Monterroso; Lucía Navas Santos; Cristina Elena Carmona Moriel; Mª Dolores López Zamorano; Rafael Santamaría Olmo; Rodolfo Crespo Montero

    2015-01-01

    Introducción: En la Hipertensión Arterial (HTA) existen una serie de factores asociados a la misma que inciden en la Calidad de Vida Relacionada con la Salud (CVRS) de la población en general, como es el caso de la Diabetes Mellitus, el hábito tabáquico, alimentación, etc. Objetivo: Analizar la CVRS y los factores asociados a ésta, en pacientes con HTA controlados en la Unidad de Hipertensión de la Unidad de Gestión Clínica (UGC) Nefrología del Hospital Universitario Reina Sofía (HURS) de Cór...

  7. Modification of a Kowa RC-2 fundus camera for self-photography without the use of mydriatics.

    Science.gov (United States)

    Philpott, D E; Bailey, P F; Harrison, G; Turnbill, C

    1979-01-01

    Research on retinal circulation during space flight required the development of a simple technique to provide self monitoring of blood vessel changes in the fundus without the use of mydriatics. A Kowa RC-2 fundus camera was modified for self-photography by the use of a bite plate for positioning and cross hairs for focusing the subject's retina relative to the film plane. Dilation of the pupils without the use of mydriatics was accomplished by dark adaption of the subject. Pictures were obtained without pupil constriction by the use of a high speed strobe light. This method also has applications for clinical medicine.

  8. A STUDY TO COMPARE FUNDUS FLUORESCEIN ANGIOGRAPHY AND OPTICAL COHERENCE TOMOGRAPHY IN AGE RELATED MACULAR DEGENERATION

    Directory of Open Access Journals (Sweden)

    Rani Sujatha

    2016-02-01

    Full Text Available PURPOSE To compare the diagnostic accuracy of optical coherence tomography with Fundus Fluorescein Angiography in diagnosing Age related macular degeneration. METHODS A total 25 patients newly diagnosed as Age related macular degeneration were included in the study. The study was done during the time period between August 2013 to November 2015 this is a prospective randomized hospital based study. RESULTS Maximum no of patients affected belonged to the age group of 50-70 years and 60% were females. The most common symptom was defective vision accounting for 92%. Hypertension and hyperlipidemia were the most common risk factors. 12% of the cases had unilateral disease and 88% had bilateral disease. 6% of eyes were normal in both FFA and OCT. 62% of the eyes by FFA and 61% of the eyes by OCT had dry ARMD and 32 % of the eye by FFA and 33 % by OCT had wet ARMD. CONCLUSION Fundus Fluorescein Angiography is the gold standard tool for screening ARMD and OCT is more specific in detecting early subretinal neovascular membrane and also to assess the activity of the neovascular membranes. Hence OCT is superior to FFA in diagnosing early wet ARMD and thus helps in early management of patients with ARMD.

  9. Unusual optical coherence tomography and fundus autofluorescence findings of eclipse retinopathy

    Directory of Open Access Journals (Sweden)

    Kun-Hsien Li

    2012-01-01

    Full Text Available A 63-year-old female patient complained of dimness in the central field of vision in the left eye after viewing an annular partial eclipse without adequate eye protection on 22 July 2009. Fundoscopy showed a wrinkled macular surface. Fundus autofluorescence study revealed well-demarcated hyperautofluorescence at the fovea. Optical coherence tomography demonstrated tiny intraretinal cysts. Fluorescein angiography and indocyanine green angiography were unremarkable. Epimacular membrane developed in the following month with deteriorated vision. Vitrectomy, epiretinal membrane and internal limiting membrane peeling were performed. Vision was restored to 20/20 after the operation. Direct sun-gazing may damage the retinal structures resulting in macular inflammation and increased focal metabolism, which explains the hyperautofluorescence. It may also induce epimacular membrane. Fundus autofluorescence might represent a useful technique to detect subtle solar-induced injuries of the retina. The visual prognosis is favorable but prevention remains the mainstay of treatment. Public health education is mandatory in reducing visual morbidity.

  10. Detection of Blood Vessels in Color Fundus Images using a Local Radon Transform

    Directory of Open Access Journals (Sweden)

    Reza Pourreza

    2010-09-01

    Full Text Available Introduction: This paper addresses a method for automatic detection of blood vessels in color fundus images which utilizes two main tools: image partitioning and local Radon transform. Material and Methods: The input images are firstly divided into overlapping windows and then the Radon transform is applied to each. The maximum of the Radon transform in each window corresponds to the probable available sub-vessel. To verify the detected sub-vessel, the maximum is compared with a predefined threshold. The verified sub-vessels are reconstructed using the Radon transform information. All detected and reconstructed sub-vessels are finally combined to make the final vessel tree. Results: The algorithm’s performance was evaluated numerically by applying it to 40 images of DRIVE database, a standard retinal image database. The vessels were extracted manually by two physicians. This database was used to test and compare the available and proposed algorithms for vessel detection in color fundus images. By comparing the output of the algorithm with the manual results, the two parameters TPR and FPR were calculated for each image and the average of TPRs and FPRs were used to plot the ROC curve. Discussion and Conclusion: Comparison of the ROC curve of this algorithm with other algorithms demonstrated the high achieved accuracy. Beside the high accuracy, the Radon transform which is integral-based makes the algorithm robust against noise.

  11. Fundus autofluorescence and optical coherence tomography in the management of progressive outer retinal necrosis

    Science.gov (United States)

    Yeh, Steven; Wong, Wai T.; Weichel, Eric D.; Lew, Julie C.; Chew, Emily Y.; Nussenblatt, Robert B.

    2011-01-01

    A 41 year-old female patient with acquired immune deficiency syndrome (AIDS) presented with progressive nasal visual field loss in her right eye. Ophthalmic exam revealed widespread areas of retinal opacification with hemorrhage consistent with progressive outer retinal necrosis (PORN), which was confirmed by polymerase chain reaction (PCR) for varicella zoster virus (VZV) DNA. The patient was treated with intravenous and intravitreal foscarnet and ganciclovir with a resultant improvement clinically. Optical coherence tomography (OCT) and fundus autofluorescence (FAF) imaging revealed progressive changes indicative of widespread retinal pigment epithelial (RPE) and outer retinal dysfunction. OCT was useful in documenting progressive changes in macular architecture during therapy including neurosensory elevation, cystoid macular edema, and severe outer retinal necrosis, at initial exam, 1 week, and 1 month follow-up. Fundus autofluorescence revealed areas of stippled, hyperfluorescence within extensive zones of hypofluorescence, which progressed during the follow-up period. These areas appeared to represent lipofuscin or its photoreactive components within larger regions of RPE loss. The combination of OCT and FAF was useful in the characterization of the RPE and retinal anatomy in this patient with PORN. PMID:20337261

  12. Unusual Fundus Autofluorescence Appearance in a Patient with Hydroxychloroquine Retinal Toxicity

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    Sleiman Abou-Ltaif

    2015-06-01

    Full Text Available Purpose: To report an unusual fundus autofluorescence aspect in a patient with suspected hydroxychloroquine retinal toxicity. Method: Case report of an unusual presentation of a patient treated for 9 consecutive years with a therapeutically recommended dose of hydroxychloroquine. Result: We report the case of a 53-year-old Caucasian female treated with 400 mg hydroxychloroquine for rheumatoid arthritis over 9 years, currently on methotrexate and folinic acid, who stopped treatment 3 years ago. The cumulative dose is estimated at 1.314 kg. She recently noticed a reduction of vision in both eyes to 0.34 logMAR, with colour vision problems and major distortion in central vision. Fundus autofluorescence revealed minimal foveal pigmentary changes and more pronounced changes in the retina elsewhere. Foveal changes were confirmed by optical coherence tomography in both eyes. The patient did not report any colour perception difficulties or night vision problems and has no family history of any eye condition. Her visual field tested by an optician was full, with some central changes. Conclusion: Retinal toxicity from hydroxychloroquine can present in a different aspect than the commonly known retinal toxicity, and it happens even after years of cessation of the drug. The role of cumulative dose in toxicity is supported in this paper.

  13. Wide-field fundus autofluorescence corresponds to visual fields in chorioretinitis patients

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    Seidensticker F

    2011-11-01

    Full Text Available Florian Seidensticker1, Aljoscha S Neubauer1, Tamer Wasfy1,2, Carmen Stumpf1, Stephan R Thurau1,*, Anselm Kampik1, Marcus Kernt1,*1Department of Ophthalmology, Ludwig-Maximilians-University, Munich, Germany; 2Department of Ophthalmology, Tanta University, Tanta, Egypt *Both authors contributed equally to this workBackground and objectives: Detection of peripheral fundus autofluorescence (FAF using conventional scanning laser ophthalmoscopes (SLOs is difficult and requires pupil dilation. Here we evaluated the diagnostic properties of wide-field FAF detected by a two-laser wavelength wide-field SLO in uveitis patients.Study design/materials and methods: Observational case series of four patients suffering from different types of posterior uveitis/chorioretinitis. Wide-field FAF images were compared to visual fields. Panretinal FAF was detected by a newly developed SLO, which allows FAF imaging of up to 200° of the retina in one scan without the need for pupil dilation. Visual fields were obtained by Goldmann manual perimetry.Results: Findings from wide-field FAF imaging showed correspondence to visual field defects in all cases.Conclusion: Wide-field FAF allowed the detection of visual field defect-related alterations of the retinal pigment epithelium in all four uveitis cases.Keywords: fundus autofluorescence (FAF, Optomap, wide-field scanning laser ophthalmoscopy, imaging, uveitis, visual field

  14. [Fundus autofluorescence. Has it a place in the management of diabetic macular edema?

    Science.gov (United States)

    Zbiba, W; Baba, A; Bouayed, E; Daldoul, A

    2016-11-01

    Analyze the characteristics of fundus autofluorescence of diabetic macular edema and study the association between these characteristics and visual function. Our study included 18 patients (28 eyes) with clinically significant diabetic macular edema. All patients had a complete eye examination with a fundus autofluorescence imaging and optical coherence tomography. The central macular thickness and central macular volume were measured. The integrity of the inner segment-outer segment junction and the integrity of the external limiting membrane were also evaluated in the same area. Among the 28 eyes studied, 8 had normal autofluorescence. The remaining 20 eyes had abnormal autofluorescence: a hyper-cystoid autofluorescence in 5 eyes (25%), hyper-spot autofluorescence in 8 eyes (40%), and hypo-irregular autofluorescence in 5 eyes (25%). Best corrected visual acuity was significantly better in patients with normal autofluorescence and those with hyper-cystoid autofluorescence. There was no significant difference in central macular thickness (P=0.186) and central macular volume (P=0.191) between the four groups. The autofluorescence is a simple, fast, and non-invasive technique for the study of diabetic macular edema with good correlation to the visual function as well as to the extent of damage to the retina. It is, therefore, a possible alternative to other invasive imaging techniques in particular in the long term monitoring of diabetic macular edema. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  15. ULTRA-WIDE-FIELD FUNDUS AUTOFLUORESCENCE FINDINGS IN PATIENTS WITH ACUTE ZONAL OCCULT OUTER RETINOPATHY.

    Science.gov (United States)

    Shifera, Amde Selassie; Pennesi, Mark E; Yang, Paul; Lin, Phoebe

    2017-06-01

    To determine whether ultra-wide-field fundus autofluorescence (UWFFAF) findings in acute zonal occult outer retinopathy correlated well with perimetry, optical coherence tomography, and electroretinography findings. Retrospective observational study on 16 eyes of 10 subjects with AZOOR seen at a single referral center from October 2012 to March 2015 who had UWFFAF performed. Chi-square analysis was performed to compare categorical variables, and Mann-Whitney U test used for comparisons of nonparametric continuous variables. All eyes examined within 3 months of symptom onset (five of the five eyes) had diffusely hyperautofluorescent areas on UWFFAF. The remaining eyes contained hypoautofluorescent lesions with hyperautofluorescent borders. In 11/16 (68.8%) eyes, UWFFAF showed the full extent of lesions that would not have been possible with standard fundus autofluorescence centered on the fovea. There were 3 patterns of spread: centrifugal spread (7/16, 43.8%), centripetal spread (5/16, 31.3%), and centrifugal + centripetal spread (4/16, 25.0%). The UWFFAF lesions corresponded well with perimetric, optical coherence tomography, and electroretinography abnormalities. The UWFFAF along with optical coherence tomography can be useful in the evaluation and monitoring of acute zonal occult outer retinopathy patients.

  16. Fundus Autofluorescence Captured With a Nonmydriatic Retinal Camera in Vegetarians Versus Nonvegetarians.

    Science.gov (United States)

    Kommana, Sumana S; Padgaonkar, Pooja; Mendez, Nicole; Wu, Lesley; Szirth, Bernard; Khouri, Albert S

    2015-09-09

    A baseline level of lipofuscin in the retinal pigment epithelium (RPE) is inevitable with age, but increased levels due to increased oxidative stress can result in deleterious vision loss at older ages. As earlier detection of differences in levels can lead to superior preventative management, we studied the relationship between lipofuscin accumulation and dietary lifestyle (vegetarian vs. nonvegetarian) in the younger, healthy South Asian population using retinal fundus autofluorescence (FAF) imaging. In this pilot study, we examined 37 healthy subjects (average age 23 years ± 1) all undergoing similar stress levels as medical students at Rutgers New Jersey Medical School. Levels of lipofuscin concentrations were imaged using a FAF retinal camera (Canon CX-1). Two images (color and FAF) were captured of the left eye and included in the analysis. FAF quantitative scoring was measured in 2 regions of the captured image, the papillo-macular region (P) and the macula (M), by determining the grayscale score of a 35.5 mm(2) rectangle in the respective regions. Standardized scores (corrected to remove baseline fluorescence) were then obtained. Means, standard deviations, and t tests were performed for comparisons. Fundus autofluorescence scores of regions P and M were significantly different (P vegetarians had statistically significant lower levels of autofluorescence. These findings can have potential implications regarding long-term retinal health and risk for developing certain diseases over decades in subjects at risk for vision-threatening diseases. © 2015 Diabetes Technology Society.

  17. Automatic non-proliferative diabetic retinopathy screening system based on color fundus image.

    Science.gov (United States)

    Xiao, Zhitao; Zhang, Xinpeng; Geng, Lei; Zhang, Fang; Wu, Jun; Tong, Jun; Ogunbona, Philip O; Shan, Chunyan

    2017-10-26

    Non-proliferative diabetic retinopathy is the early stage of diabetic retinopathy. Automatic detection of non-proliferative diabetic retinopathy is significant for clinical diagnosis, early screening and course progression of patients. This paper introduces the design and implementation of an automatic system for screening non-proliferative diabetic retinopathy based on color fundus images. Firstly, the fundus structures, including blood vessels, optic disc and macula, are extracted and located, respectively. In particular, a new optic disc localization method using parabolic fitting is proposed based on the physiological structure characteristics of optic disc and blood vessels. Then, early lesions, such as microaneurysms, hemorrhages and hard exudates, are detected based on their respective characteristics. An equivalent optical model simulating human eyes is designed based on the anatomical structure of retina. Main structures and early lesions are reconstructed in the 3D space for better visualization. Finally, the severity of each image is evaluated based on the international criteria of diabetic retinopathy. The system has been tested on public databases and images from hospitals. Experimental results demonstrate that the proposed system achieves high accuracy for main structures and early lesions detection. The results of severity classification for non-proliferative diabetic retinopathy are also accurate and suitable. Our system can assist ophthalmologists for clinical diagnosis, automatic screening and course progression of patients.

  18. Bright Retinal Lesions Detection using Colour Fundus Images Containing Reflective Features

    Energy Technology Data Exchange (ETDEWEB)

    Giancardo, Luca [ORNL; Karnowski, Thomas Paul [ORNL; Chaum, Edward [ORNL; Meriaudeau, Fabrice [ORNL; Tobin Jr, Kenneth William [ORNL; Li, Yaquin [University of Tennessee, Knoxville (UTK)

    2009-01-01

    In the last years the research community has developed many techniques to detect and diagnose diabetic retinopathy with retinal fundus images. This is a necessary step for the implementation of a large scale screening effort in rural areas where ophthalmologists are not available. In the United States of America, the incidence of diabetes is worryingly increasing among the young population. Retina fundus images of patients younger than 20 years old present a high amount of reflection due to the Nerve Fibre Layer (NFL), the younger the patient the more these reflections are visible. To our knowledge we are not aware of algorithms able to explicitly deal with this type of reflection artefact. This paper presents a technique to detect bright lesions also in patients with a high degree of reflective NFL. First, the candidate bright lesions are detected using image equalization and relatively simple histogram analysis. Then, a classifier is trained using texture descriptor (Multi-scale Local Binary Patterns) and other features in order to remove the false positives in the lesion detection. Finally, the area of the lesions is used to diagnose diabetic retinopathy. Our database consists of 33 images from a telemedicine network currently developed. When determining moderate to high diabetic retinopathy using the bright lesions detected the algorithm achieves a sensitivity of 100% at a specificity of 100% using hold-one-out testing.

  19. Comparison of optical coherence tomography and fundus photography for measuring the optic disc size.

    Science.gov (United States)

    Neubauer, Aljoscha S; Krieglstein, Tina R; Chryssafis, Christos; Thiel, Martin; Kampik, Anselm

    2006-01-01

    To assess the agreement and repeatability of optic nerve head (ONH) size measurements by optical coherence tomography (OCT) as compared to conventional planimetry of fundus photographs in normal eyes. For comparison with planimetry the absolute size of the ONH of 25 eyes from 25 normal subjects were measured by both OCT and digital fundus photography (Zeiss FF camera 450). Repeatability of automated Stratus OCT measurements were investigated by repeatedly measuring the optic disc in five normal subjects. Mean disc size was 1763 +/- 186 vertically and 1632 +/- 160 microm horizontally on planimetry. On OCT, values of 1772 +/- 317 microm vertically (p = 0.82) and a significantly smaller horizontal diameter of 1492 +/- 302 microm (p = 0.04) were obtained. The 95% limits of agreement were (-546 microm; +527 microm) for vertical and (-502 microm; +782 microm) for horizontal planimetric compared to OCT measurements. In some cases large discrepancies existed. Repeatability of automatic measurements of the optic disc by OCT was moderately good with intra-class correlation coefficients (ICC) of 0.78 horizontally and 0.83 vertically. The coefficient of repeatability indicating instrument precision was 80 microm for horizontal and 168 microm for vertical measurements. OCT can be used to determine optic disc margins in moderate agreement with planimetry in normal subjects. However, in some cases significant disagreement with photographic assessment may occur making manual inspection advisable. Automatic disc detection by OCT is moderately repeatable.

  20. Automatic multiresolution age-related macular degeneration detection from fundus images

    Science.gov (United States)

    Garnier, Mickaël.; Hurtut, Thomas; Ben Tahar, Houssem; Cheriet, Farida

    2014-03-01

    Age-related Macular Degeneration (AMD) is a leading cause of legal blindness. As the disease progress, visual loss occurs rapidly, therefore early diagnosis is required for timely treatment. Automatic, fast and robust screening of this widespread disease should allow an early detection. Most of the automatic diagnosis methods in the literature are based on a complex segmentation of the drusen, targeting a specific symptom of the disease. In this paper, we present a preliminary study for AMD detection from color fundus photographs using a multiresolution texture analysis. We analyze the texture at several scales by using a wavelet decomposition in order to identify all the relevant texture patterns. Textural information is captured using both the sign and magnitude components of the completed model of Local Binary Patterns. An image is finally described with the textural pattern distributions of the wavelet coefficient images obtained at each level of decomposition. We use a Linear Discriminant Analysis for feature dimension reduction, to avoid the curse of dimensionality problem, and image classification. Experiments were conducted on a dataset containing 45 images (23 healthy and 22 diseased) of variable quality and captured by different cameras. Our method achieved a recognition rate of 93:3%, with a specificity of 95:5% and a sensitivity of 91:3%. This approach shows promising results at low costs that in agreement with medical experts as well as robustness to both image quality and fundus camera model.

  1. Consumo de alcohol y drogas y factores psicosociales asociados en adolescentes de Lima

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    Eduardo Salazar

    2004-09-01

    Full Text Available Objetivo: Determinar la prevalencia del consumo de alcohol y drogas y los factores psicosociales asociados con dicho consumo en adolescentes de Lima. Diseño: Estudio analítico de corte transversal. Material y Métodos: Se estudió una muestra de 430 adolescentes de educación secundaria de un colegio de Lima. Se utilizó el Cuestionario Tamiz de Experiencias Personales (Personal Experience Screening Questionnaire - PESQ. Resultados: Se recibió 391 encuestas válidas. La prevalencia de consumo de alcohol o drogas fue 43%, de alcohol 42,2%, de marihuana 8,7% y de cocaína 3,1%. Se encontró problema de consumo de alcohol o drogas en el 10,7%, los factores psicosociales asociados fueron distrés psicológico severo (OR 4,58 IC 95% 1,60-13,05, pensamiento problemático severo (OR 2,63 IC 95% 1,15-6,01 y abuso físico (OR 2,31 IC 95% 1,19-4,49. Conclusiones: El factor psicosocial más asociado al problema de consumo de drogas fue el distrés psicológico severo. Asimismo, se encontró asociación entre el pensamiento problemático severo y el abuso físico con dicho problema. El acoso sexual sólo se encontró asociado en los adolescentes de segundo de secundaria.

  2. El gobierno corporativo en la cooperativa de trabajo asociado Recuperar CTA

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    Carlos Mario Toro Orozco

    2012-01-01

    Full Text Available En la cooperativa de trabajo asociado Recuperar (CTA se ha logrado demostrar, a través de esta investigación, la efectividad de la concertación entre el gobierno corporativo y la vinculación de los asociados a la solución eficaz y eficiente de un problema social prioritario para una ciudad, como ha sido el reciclaje de las basuras. Es por ello que en este artículo se evidencia cómo, a partir del Gobierno Corporativo , esta organización ha logrado una proyección económica y social que le ha permitido cumplir las necesidades de los asociados, estableciendo una cultura gerencial y de resultados, por medio de lo cual se ha logrado la permanencia de dicha organización en el sector solidario, como un ejemplo de gestión y proyección social. La metodología utilizada es un estudio de corte cualitativo a partir del análisis de los diferentes aspectos para establecer los mecanismos de Gobierno Corporativo. Los resultados permiten observar que su crecimiento y permanencia en el tiempo se ha obtenido, a través de la coherencia con los valores cooperativos, la igualdad y la solidaridad con las exigencias del mercado; la participación y el control democrático; de igual forma la identidad, autonomía e independencia por parte de sus asociados.

  3. Factores asociados a síntomas depresivos en trabajadoras sexuales

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    Ingrid Mercedes Bohórquez

    2010-12-01

    Full Text Available Introducción: Las condiciones de trabajo y la violencia ejercida contra las trabajadoras sexuales han sido relacionadas con el incremento de las tasas de infecciones de transmisión sexual. Sin embargo, también se encuentran enfermedades que afectan su salud mental. Objetivos: Determinar la magnitud de síntomas depresivos y factores asociados en trabajadoras sexuales. Diseño: Estudio transversal-analítico. Lugar: Centro de salud referencial para la prevención y control de infecciones de transmisión sexual. Participantes: Trabajadoras sexuales. Intervenciones: A 117 trabajadoras sexuales, que fueron atendidas durante los meses de mayo y junio del 2010, se aplicó el test de Beck para medir la sintomatología depresiva y una encuesta para medir los siguientes factores: socio-demográficos, sociales (antecedentes de maltrato físico, psicológico y sexual en el trabajo y hábitos nocivos: alcohol y drogas, conductas sexuales de riesgo y características del trabajo (edad de inicio, años de trabajo, satisfacción con el trabajo. Principales medidas de resultados: Porcentaje de síntomas depresivos y fuerza de asociación entre los factores y la presencia de síntomas depresivos. Resultados: El 56,4% de las trabajadoras sexuales presentó algún nivel de sintomatología depresiva. El nivel de síntomas depresivos graves estuvo presente en 23,9%. Los factores que se encontraron asociados a depresión, independiente del nivel, fue el antecedente de maltrato físico frecuente, con OR=9,46, IC95% 1,05 a 85,07; p=0,045. Los factores asociados a nivel de síntomas depresivos graves fueron: ingreso económico menor a S/. 1 000.00, tener hijos, haberse iniciado en el trabajo sexual antes de los 18 años y consumo de drogas (p<0,05. Conclusiones: Más de 50% de trabajadoras presentó algún nivel de síntomas depresivos, que estuvieron asociados al antecedente de maltrato físico. Para el nivel síntomas depresivos graves, los factores asociados

  4. Color Fundus Photography, Optical Coherence Tomography, and Fluorescein Angiography in Diagnosing Polypoidal Choroidal Vasculopathy.

    Science.gov (United States)

    Chaikitmongkol, Voraporn; Khunsongkiet, Preeyanuch; Patikulsila, Direk; Ratanasukon, Mansing; Watanachai, Nawat; Jumroendararasame, Chaisiri; Mayerle, Catherine B; Han, Ian C; Chen, Connie J; Winaikosol, Pawara; Dejkriengkraikul, Chutikarn; Choovuthayakorn, Janejit; Kunavisarut, Paradee; Bressler, Neil M

    2018-05-10

    To determine sensitivity and specificity of polypoidal choroidal vasculopathy (PCV) diagnosis using color fundus photography (CFP), optical coherence tomography (OCT) and fundus fluorescein angiography (FFA) without indocyanine-green angiography (ICGA). Validity analysis. Treatment-naïve eyes with serous/serosanguinous maculopathy undergoing CFP, OCT, FFA and ICGA imaging before treatment at a university-hospital in Thailand (January 2013 to June 2015) were identified. Images of each subject were categorized into 4 sets (set A: CFP; set B: CFP+OCT; set C: CFP+FFA; set D: CFP+OCT+FFA). Six graders, 3 from Thailand (PCV endemic area) and 3 from U.S. (non-endemic area), individually reviewed each set (without ICG), and determined if the presumed diagnosis was PCV. In parallel, 2 other graders confirmed if each case had PCV or not using EVEREST criteria (including ICGA). Sensitivity and specificity of a PCV diagnosis with each set (without ICGA) were analyzed compared with diagnoses including ICGA. Of 119 study eyes (113 subjects, 57% male, mean age±SD 59.9±13.8), definite PCV diagnosis was 40.3%. Sensitivity of sets A, B, C, D: 0.63 (95%CI: 0.47-0.76), 0.83 (95%CI: 0.69-0.92), 0.54 (95%CI: 0.39-0.68), 0.67 (95%CI: 0.51-0.79). Specificity were 0.93 (95% CI: 0.84-0.97), 0.83 (95%CI: 0.72-0.91), 0.97 (95%CI: 0.89-0.99), 0.92 (95%CI: 0.82-0.97). Accuracies: 0.81 (95%CI: 0.73-0.88), 0.83 (95%CI: 0.76-0.90), 0.79 (95%CI: 0.73-0.87), 0.82 (95%CI: 0.74-0.88). Discrepancies between Thai and US graders existed through sets A, C, and D. These data suggest without ICGA, fundus photography combined with OCT provides high sensitivity and high specificity to diagnosis PCV; adding FFA does not improve accuracy. Copyright © 2018 Elsevier Inc. All rights reserved.

  5. An Automated System for the Detection and Classification of Retinal Changes Due to Red Lesions in Longitudinal Fundus Images

    NARCIS (Netherlands)

    Adal, K.M.; Van Etten, Peter G.; Martinez, Jose P; Rouwen, Kenneth W.; Vermeer, K.A.; van Vliet, L.J.

    People with diabetes mellitus need annual screening to check for the development of diabetic retinopathy. Tracking small retinal changes due to early diabetic retinopathy lesions in longitudinal fundus image sets is challenging due to intra- and inter-visit variability in illumination and image

  6. Nitrergic Pathway Is the Main Contributing Mechanism in the Human Gastric Fundus Relaxation: An In Vitro Study.

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    Yang Won Min

    Full Text Available Human gastric fundus relaxation is mediated by intrinsic inhibitory pathway. We investigated the roles of nitrergic and purinergic pathways, two known inhibitory factors in gastric motility, on spontaneous and nerve-evoked contractions in human gastric fundus muscles.Gastric fundus muscle strips (12 circular and 13 longitudinal were obtained from patients without previous gastrointestinal motility disorder who underwent gastrectomy for stomach cancer. Using these specimens, we examined basal tone, peak, amplitude, and frequency of spontaneous contractions, and peak and nadir values under electrical field stimulation (EFS, 150 V, 0.3 ms, 10 Hz, 20 s. To examine responses to purinergic and nitrergic inhibition without cholinergic innervation, atropine (muscarinic antagonist, 1 μM, MRS2500 (a purinergic P2Y1 receptor antagonist, 1 μM, and N-nitro-L-arginine (L-NNA, a nitric oxide synthase inhibitor, 100 μM were added sequentially for spontaneous and electrically-stimulated contractions. Tetrodotoxin was used to confirm any neuronal involvement.In spontaneous contraction, L-NNA increased basal tone and peak in both muscle layers, while amplitude and frequency were unaffected. EFS (up to 10 Hz uniformly induced initial contraction and subsequent relaxation in a frequency-dependent manner. Atropine abolished initial on-contraction and induced only relaxation during EFS. While MRS2500 showed no additional influence, L-NNA reversed relaxation (p = 0.012 in circular muscle, and p = 0.006 in longitudinal muscle. Tetrodotoxin abolished any EFS-induced motor response.The relaxation of human gastric fundus muscle is reduced by nitrergic inhibition. Hence, nitrergic pathway appears to be the main mechanism for the human gastric fundus relaxation.

  7. Automated segmentation of geographic atrophy of the retinal epithelium via random forests in AREDS color fundus images☆

    Science.gov (United States)

    Feeny, Albert K.; Tadarati, Mongkol; Freund, David E.; Bressler, Neil M.; Burlina, Philippe

    2015-01-01

    Background Age-related macular degeneration (AMD), left untreated, is the leading cause of vision loss in people older than 55. Severe central vision loss occurs in the advanced stage of the disease, characterized by either the in growth of choroidal neovascularization (CNV), termed the “wet” form, or by geographic atrophy (GA) of the retinal pigment epithelium (RPE) involving the center of the macula, termed the “dry” form. Tracking the change in GA area over time is important since it allows for the characterization of the effectiveness of GA treatments. Tracking GA evolution can be achieved by physicians performing manual delineation of GA area on retinal fundus images. However, manual GA delineation is time-consuming and subject to inter-and intra-observer variability. Methods We have developed a fully automated GA segmentation algorithm in color fundus images that uses a supervised machine learning approach employing a random forest classifier. This algorithm is developed and tested using a dataset of images from the NIH-sponsored Age Related Eye Disease Study (AREDS). GA segmentation output was compared against a manual delineation by a retina specialist. Results Using 143 color fundus images from 55 different patient eyes, our algorithm achieved PPV of 0.82±0.19, and NPV of 0:95±0.07. Discussion This is the first study, to our knowledge, applying machine learning methods to GA segmentation on color fundus images and using AREDS imagery for testing. These preliminary results show promising evidence that machine learning methods may have utility in automated characterization of GA from color fundus images. PMID:26318113

  8. Automated segmentation of geographic atrophy of the retinal epithelium via random forests in AREDS color fundus images.

    Science.gov (United States)

    Feeny, Albert K; Tadarati, Mongkol; Freund, David E; Bressler, Neil M; Burlina, Philippe

    2015-10-01

    Age-related macular degeneration (AMD), left untreated, is the leading cause of vision loss in people older than 55. Severe central vision loss occurs in the advanced stage of the disease, characterized by either the in growth of choroidal neovascularization (CNV), termed the "wet" form, or by geographic atrophy (GA) of the retinal pigment epithelium (RPE) involving the center of the macula, termed the "dry" form. Tracking the change in GA area over time is important since it allows for the characterization of the effectiveness of GA treatments. Tracking GA evolution can be achieved by physicians performing manual delineation of GA area on retinal fundus images. However, manual GA delineation is time-consuming and subject to inter-and intra-observer variability. We have developed a fully automated GA segmentation algorithm in color fundus images that uses a supervised machine learning approach employing a random forest classifier. This algorithm is developed and tested using a dataset of images from the NIH-sponsored Age Related Eye Disease Study (AREDS). GA segmentation output was compared against a manual delineation by a retina specialist. Using 143 color fundus images from 55 different patient eyes, our algorithm achieved PPV of 0.82±0.19, and NPV of 0:95±0.07. This is the first study, to our knowledge, applying machine learning methods to GA segmentation on color fundus images and using AREDS imagery for testing. These preliminary results show promising evidence that machine learning methods may have utility in automated characterization of GA from color fundus images. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Ultra-wide field imaging system and traditional retinal examinations for screening fundus changes after cataract surgery.

    Science.gov (United States)

    Peng, Jie; Zhang, Qi; Jin, Hai-Ying; Lu, Wu-Yi; Zhao, Pei-Quan

    2016-01-01

    To compare the results of non-mydriatic ultra-wide field imaging system, mydriatic slit-lamp lens (Volk +90 D) and mydriatic Goldmann three-mirror contact lens examinations in screening fundus lesions among patients after cataract surgery. Non-mydriatic images were obtained with an Optomap panoramic 200Tx (Optomap 200Tx) 3d after surgery and graded by a blinded ophthalmologist. A mydriatic slit-lamp lens examination was performed by another blinded retinal specialist on the same day. A third blinded retinal specialist examined patients two weeks after surgery using a Goldmann three-mirror contact lens. In total, 160 patients (184 eyes) were examined, and 66, 69, and 75 cases of retinal lesion(s) were identified using the Optomap 200Tx, slit-lamp lens, and Goldmann three-mirror contact lens, respectively. In 13 cases, fundus changes were sight-threatening. The results obtained by Optomap 200Tx examination and by mydriatic slit-lamp lens examination have good consistency (P=0.375, Kappa=0.942). The mydriatic Goldmann three-mirror lens examination revealed more fundus lesions but are consistent with Optomap 200Tx (P=0.004, Kappa=0.897) and mydriatic slit-lamp lens examination (P=0.031, Kappa=0.932). Early post-operative fundus screening in cataract patients is extremely important and necessary to prevent further vision loss. Wide-field imaging is a feasible and convenient tool for fundus examination that can be used as a primary screening method among patients after cataract surgery.

  10. Classification of Diabetic Macular Edema and Its Stages Using Color Fundus Image

    Institute of Scientific and Technical Information of China (English)

    Muhammad Zubair; Shoab A. Khan; Ubaid Ullah Yasin

    2014-01-01

    Diabetic macular edema (DME) is a retinal thickening involving the center of the macula. It is one of the serious eye diseases which affects the central vision and can lead to partial or even complete visual loss. The only cure is timely diagnosis, prevention, and treatment of the disease. This paper presents an automated system for the diagnosis and classification of DME using color fundus image. In the proposed technique, first the optic disc is removed by applying some preprocessing steps. The preprocessed image is then passed through a classifier for segmentation of the image to detect exudates. The classifier uses dynamic thresholding technique by using some input parameters of the image. The stage classification is done on the basis of anearly treatment diabetic retinopathy study (ETDRS) given criteria to assess the severity of disease. The proposed technique gives a sensitivity, specificity, and accuracy of 98.27%, 96.58%, and 96.54%, respectively on publically available database.

  11. Deep Convolutional Neural Network-Based Early Automated Detection of Diabetic Retinopathy Using Fundus Image.

    Science.gov (United States)

    Xu, Kele; Feng, Dawei; Mi, Haibo

    2017-11-23

    The automatic detection of diabetic retinopathy is of vital importance, as it is the main cause of irreversible vision loss in the working-age population in the developed world. The early detection of diabetic retinopathy occurrence can be very helpful for clinical treatment; although several different feature extraction approaches have been proposed, the classification task for retinal images is still tedious even for those trained clinicians. Recently, deep convolutional neural networks have manifested superior performance in image classification compared to previous handcrafted feature-based image classification methods. Thus, in this paper, we explored the use of deep convolutional neural network methodology for the automatic classification of diabetic retinopathy using color fundus image, and obtained an accuracy of 94.5% on our dataset, outperforming the results obtained by using classical approaches.

  12. 3D Reconstruction of the Retinal Arterial Tree Using Subject-Specific Fundus Images

    Science.gov (United States)

    Liu, D.; Wood, N. B.; Xu, X. Y.; Witt, N.; Hughes, A. D.; Samcg, Thom

    Systemic diseases, such as hypertension and diabetes, are associated with changes in the retinal microvasculature. Although a number of studies have been performed on the quantitative assessment of the geometrical patterns of the retinal vasculature, previous work has been confined to 2 dimensional (2D) analyses. In this paper, we present an approach to obtain a 3D reconstruction of the retinal arteries from a pair of 2D retinal images acquired in vivo. A simple essential matrix based self-calibration approach was employed for the "fundus camera-eye" system. Vessel segmentation was performed using a semi-automatic approach and correspondence between points from different images was calculated. The results of 3D reconstruction show the centreline of retinal vessels and their 3D curvature clearly. Three-dimensional reconstruction of the retinal vessels is feasible and may be useful in future studies of the retinal vasculature in disease.

  13. Automated diabetic retinopathy detection in smartphone-based fundus photography using artificial intelligence.

    Science.gov (United States)

    Rajalakshmi, Ramachandran; Subashini, Radhakrishnan; Anjana, Ranjit Mohan; Mohan, Viswanathan

    2018-06-01

    To assess the role of artificial intelligence (AI)-based automated software for detection of diabetic retinopathy (DR) and sight-threatening DR (STDR) by fundus photography taken using a smartphone-based device and validate it against ophthalmologist's grading. Three hundred and one patients with type 2 diabetes underwent retinal photography with Remidio 'Fundus on phone' (FOP), a smartphone-based device, at a tertiary care diabetes centre in India. Grading of DR was performed by the ophthalmologists using International Clinical DR (ICDR) classification scale. STDR was defined by the presence of severe non-proliferative DR, proliferative DR or diabetic macular oedema (DME). The retinal photographs were graded using a validated AI DR screening software (EyeArt TM ) designed to identify DR, referable DR (moderate non-proliferative DR or worse and/or DME) or STDR. The sensitivity and specificity of automated grading were assessed and validated against the ophthalmologists' grading. Retinal images of 296 patients were graded. DR was detected by the ophthalmologists in 191 (64.5%) and by the AI software in 203 (68.6%) patients while STDR was detected in 112 (37.8%) and 146 (49.3%) patients, respectively. The AI software showed 95.8% (95% CI 92.9-98.7) sensitivity and 80.2% (95% CI 72.6-87.8) specificity for detecting any DR and 99.1% (95% CI 95.1-99.9) sensitivity and 80.4% (95% CI 73.9-85.9) specificity in detecting STDR with a kappa agreement of k = 0.78 (p < 0.001) and k = 0.75 (p < 0.001), respectively. Automated AI analysis of FOP smartphone retinal imaging has very high sensitivity for detecting DR and STDR and thus can be an initial tool for mass retinal screening in people with diabetes.

  14. Application of 3-dimensional printing technology to construct an eye model for fundus viewing study.

    Directory of Open Access Journals (Sweden)

    Ping Xie

    Full Text Available To construct a life-sized eye model using the three-dimensional (3D printing technology for fundus viewing study of the viewing system.We devised our schematic model eye based on Navarro's eye and redesigned some parameters because of the change of the corneal material and the implantation of intraocular lenses (IOLs. Optical performance of our schematic model eye was compared with Navarro's schematic eye and other two reported physical model eyes using the ZEMAX optical design software. With computer aided design (CAD software, we designed the 3D digital model of the main structure of the physical model eye, which was used for three-dimensional (3D printing. Together with the main printed structure, polymethyl methacrylate(PMMA aspherical cornea, variable iris, and IOLs were assembled to a physical eye model. Angle scale bars were glued from posterior to periphery of the retina. Then we fabricated other three physical models with different states of ammetropia. Optical parameters of these physical eye models were measured to verify the 3D printing accuracy.In on-axis calculations, our schematic model eye possessed similar size of spot diagram compared with Navarro's and Bakaraju's model eye, much smaller than Arianpour's model eye. Moreover, the spherical aberration of our schematic eye was much less than other three model eyes. While in off- axis simulation, it possessed a bit higher coma and similar astigmatism, field curvature and distortion. The MTF curves showed that all the model eyes diminished in resolution with increasing field of view, and the diminished tendency of resolution of our physical eye model was similar to the Navarro's eye. The measured parameters of our eye models with different status of ametropia were in line with the theoretical value.The schematic eye model we designed can well simulate the optical performance of the human eye, and the fabricated physical one can be used as a tool in fundus range viewing research.

  15. Centrifugal Expansion of Fundus Autofluorescence Patterns in Stargardt Disease Over Time

    Science.gov (United States)

    Cukras, Catherine A.; Wong, Wai T.; Caruso, Rafael; Cunningham, Denise; Zein, Wadih; Sieving, Paul

    2012-01-01

    Objective Changing lipofuscin and melanin content in RPE cells has been hypothesized to contribute to Stargardt disease pathogenesis. Longitudinal study of autofluorescence in Stargardt disease which reflect changing fluorophore compositions can reveal aspects of disease progression not previously evident. Method We examined the temporal-spatial patterns of fundus autofluorescence with excitation at both 488 nm (standard fundus autofluorescence, FAF) and 795nm (near infrared autofluorescence, NIA) in a longitudinal case series involving 8 eyes of 4 patients (range of follow-up = 11 to 57 months; mean = 39 months). Image processing was performed to analyze spatial and temporal cross-modality associations. Results Longitudinal FAF imaging of fleck lesions revealed hyperautofluorescent lesions that extended in a centrifugal direction from the fovea with time. Patterns of spread were non-random and followed a radial path that leaves behind a trail of diminishing autofluorescence. Longitudinal NIA imaging also demonstrated centrifugal lesion spread, but with fewer hyperautofluorescent lesions, suggestive of more transient hyperautofluorescence and more rapid decay at longer wavelengths. FAF and NIA abnormalities were spatially correlated to each other, and together reflect systematic progressions in fleck distribution and fluorophore composition occurring during the natural history of the disease. Conclusion Stargardt disease fleck lesions do not evolve randomly in location but instead follow consistent patterns of radial expansion and a systematic decay of autofluorescence that reflect changing lipofuscin and melanin compositions in RPE cells. These progressive foveal-to-peripheral changes are helpful in elucidating molecular and cellular mechanisms underlying Stargardt disease and may constitute potential outcome measures in clinical trials. PMID:21987580

  16. COMPARISON OF MANUAL AND SEMIAUTOMATED FUNDUS AUTOFLUORESCENCE ANALYSIS OF MACULAR ATROPHY IN STARGARDT DISEASE PHENOTYPE.

    Science.gov (United States)

    Kuehlewein, Laura; Hariri, Amir H; Ho, Alexander; Dustin, Laurie; Wolfson, Yulia; Strauss, Rupert W; Scholl, Hendrik P N; Sadda, SriniVas R

    2016-06-01

    To evaluate manual and semiautomated grading techniques for assessing decreased fundus autofluorescence (DAF) in patients with Stargardt disease phenotype. Certified reading center graders performed manual and semiautomated (region finder-based) grading of confocal scanning laser ophthalmoscopy (cSLO) fundus autofluorescence (FAF) images for 41 eyes of 22 patients. Lesion types were defined based on the black level and sharpness of the border: definite decreased autofluorescence (DDAF), well, and poorly demarcated questionably decreased autofluorescence (WDQDAF, PDQDAF). Agreement in grading between the two methods and inter- and intra-grader agreement was assessed by kappa coefficients (κ) and intraclass correlation coefficients (ICC). The mean ± standard deviation (SD) area was 3.07 ± 3.02 mm for DDAF (n = 31), 1.53 ± 1.52 mm for WDQDAF (n = 9), and 6.94 ± 10.06 mm for PDQDAF (n = 17). The mean ± SD absolute difference in area between manual and semiautomated grading was 0.26 ± 0.28 mm for DDAF, 0.20 ± 0.26 mm for WDQDAF, and 4.05 ± 8.32 mm for PDQDAF. The ICC (95% confidence interval) for method comparison was 0.992 (0.984-0.996) for DDAF, 0.976 (0.922-0.993) for WDQDAF, and 0.648 (0.306-0.842) for PDQDAF. Inter- and intra-grader agreement in manual and semiautomated quantitative grading was better for DDAF (0.981-0.996) and WDQDAF (0.995-0.999) than for PDQDAF (0.715-0.993). Manual and semiautomated grading methods showed similar levels of reproducibility for assessing areas of decreased autofluorescence in patients with Stargardt disease phenotype. Excellent agreement and reproducibility were observed for well demarcated lesions.

  17. Association between fundus autofluorescence and visual outcome in surgically closed macular holes.

    Science.gov (United States)

    Lee, Young Seob; Yu, Seung-Young; Cho, Nam Suk; Kim, Moo Sang; Kim, Young Gyun; Kim, Eung Suk; Kwak, Hyung Woo

    2013-06-01

    To investigate the association between fundus autofluorescence (FAF) and visual acuity, recovery of foveal microstructure, and FAF in surgically closed macular holes. Twenty-six eyes with surgically closed macular hole were classified into two groups based on foveal FAF: normal autofluorescence (NAF) or increased autofluorescence (IAF). The association between foveal FAF and visual acuity was analyzed. In addition, we examined the relationship between recovery of the foveal microstructure assessed by spectral domain optical coherence tomography and FAF after macular hole surgery. At 1 month and 6 months after surgery, there were 9 NAF eyes and 17 IAF eyes. There were no differences between NAF and IAF eyes at 1 month and 6 months after surgery. Preoperative best-corrected visual acuity (logarithm of the minimum angle of resolution) did not differ between groups. Best-corrected visual acuity was significantly higher in the NAF group than in the IAF group at 1 month postoperatively (0.59 ± 0.34 vs. 0.91 ± 0.36, P = 0.044) and tended to be higher at 6 months (0.37 ± 0.38 vs. 0.69 ± 0.53, P = 0.126). Restoration of photoreceptor external limiting membrane differed significantly in 8 NAF eyes (89%) and 4 IAF eyes (24%) at postoperation 1 month (P = 0.001). After 6 months, external limiting membrane was restored in all 9 NAF eyes (100%) and in only 11 IAF eyes (65%) (P = 0.042). Fundus autofluorescence findings observed in surgically closed macular holes correlated with visual improvement and photoreceptor status. Eyes with visual improvement had restoration of normal foveal autofluorescence and retinal microstructure, whereas eyes with persistent foveal hyperautofluorescence did not achieve complete restoration of the retinal microstructure, and visual improvement was not as significant.

  18. Application of 3-dimensional printing technology to construct an eye model for fundus viewing study.

    Science.gov (United States)

    Xie, Ping; Hu, Zizhong; Zhang, Xiaojun; Li, Xinhua; Gao, Zhishan; Yuan, Dongqing; Liu, Qinghuai

    2014-01-01

    To construct a life-sized eye model using the three-dimensional (3D) printing technology for fundus viewing study of the viewing system. We devised our schematic model eye based on Navarro's eye and redesigned some parameters because of the change of the corneal material and the implantation of intraocular lenses (IOLs). Optical performance of our schematic model eye was compared with Navarro's schematic eye and other two reported physical model eyes using the ZEMAX optical design software. With computer aided design (CAD) software, we designed the 3D digital model of the main structure of the physical model eye, which was used for three-dimensional (3D) printing. Together with the main printed structure, polymethyl methacrylate(PMMA) aspherical cornea, variable iris, and IOLs were assembled to a physical eye model. Angle scale bars were glued from posterior to periphery of the retina. Then we fabricated other three physical models with different states of ammetropia. Optical parameters of these physical eye models were measured to verify the 3D printing accuracy. In on-axis calculations, our schematic model eye possessed similar size of spot diagram compared with Navarro's and Bakaraju's model eye, much smaller than Arianpour's model eye. Moreover, the spherical aberration of our schematic eye was much less than other three model eyes. While in off- axis simulation, it possessed a bit higher coma and similar astigmatism, field curvature and distortion. The MTF curves showed that all the model eyes diminished in resolution with increasing field of view, and the diminished tendency of resolution of our physical eye model was similar to the Navarro's eye. The measured parameters of our eye models with different status of ametropia were in line with the theoretical value. The schematic eye model we designed can well simulate the optical performance of the human eye, and the fabricated physical one can be used as a tool in fundus range viewing research.

  19. Automated detection of retinal landmarks for the identification of clinically relevant regions in fundus photography

    Science.gov (United States)

    Ometto, Giovanni; Calivá, Francesco; Al-Diri, Bashir; Bek, Toke; Hunter, Andrew

    2016-03-01

    Automatic, quick and reliable identification of retinal landmarks from fundus photography is key for measurements used in research, diagnosis, screening and treating of common diseases affecting the eyes. This study presents a fast method for the detection of the centre of mass of the vascular arcades, optic nerve head (ONH) and fovea, used in the definition of five clinically relevant areas in use for screening programmes for diabetic retinopathy (DR). Thirty-eight fundus photographs showing 7203 DR lesions were analysed to find the landmarks manually by two retina-experts and automatically by the proposed method. The automatic identification of the ONH and fovea were performed using template matching based on normalised cross correlation. The centre of mass of the arcades was obtained by fitting an ellipse on sample coordinates of the main vessels. The coordinates were obtained by processing the image with hessian filtering followed by shape analyses and finally sampling the results. The regions obtained manually and automatically were used to count the retinal lesions falling within, and to evaluate the method. 92.7% of the lesions were falling within the same regions based on the landmarks selected by the two experts. 91.7% and 89.0% were counted in the same areas identified by the method and the first and second expert respectively. The inter-repeatability of the proposed method and the experts is comparable, while the 100% intra-repeatability makes the algorithm a valuable tool in tasks like analyses in real-time, of large datasets and of intra-patient variability.

  20. Multispectral imaging of the ocular fundus using light emitting diode illumination.

    Science.gov (United States)

    Everdell, N L; Styles, I B; Calcagni, A; Gibson, J; Hebden, J; Claridge, E

    2010-09-01

    We present an imaging system based on light emitting diode (LED) illumination that produces multispectral optical images of the human ocular fundus. It uses a conventional fundus camera equipped with a high power LED light source and a highly sensitive electron-multiplying charge coupled device camera. It is able to take pictures at a series of wavelengths in rapid succession at short exposure times, thereby eliminating the image shift introduced by natural eye movements (saccades). In contrast with snapshot systems the images retain full spatial resolution. The system is not suitable for applications where the full spectral resolution is required as it uses discrete wavebands for illumination. This is not a problem in retinal imaging where the use of selected wavelengths is common. The modular nature of the light source allows new wavelengths to be introduced easily and at low cost. The use of wavelength-specific LEDs as a source is preferable to white light illumination and subsequent filtering of the remitted light as it minimizes the total light exposure of the subject. The system is controlled via a graphical user interface that enables flexible control of intensity, duration, and sequencing of sources in synchrony with the camera. Our initial experiments indicate that the system can acquire multispectral image sequences of the human retina at exposure times of 0.05 s in the range of 500-620 nm with mean signal to noise ratio of 17 dB (min 11, std 4.5), making it suitable for quantitative analysis with application to the diagnosis and screening of eye diseases such as diabetic retinopathy and age-related macular degeneration.

  1. Detection of motion artifacts in optical coherence tomography using the fundus enhancement system

    International Nuclear Information System (INIS)

    Schaudig, U.; Skevas, C.; Scholz, F.

    2007-01-01

    Extensive artefacts due to major eye movements are detectable in optical coherence tomography images (OCT), but frequency and extent of small eye movements have not been studied. To investigate frequency and extent of irregularities in OCT imaging due to eye movements during the scanning process in OCT. A fundus enhancement system (FES) originally designed to improve retinal image quality in a conventional OCT device (Zeiss Stratus OCT) in order to integrate OCT images into fluorescence angiographies was used to record the scanning process and review OCT-scan acquisition in slow motion. A horizontal and a vertical single line scan of 5 mm length through the center of fixation were obtained in 40 eyes of 20 normal healthy subjects, all with a visual acuity of at least 20/20. Scans were investigated for loss of fixation and eye movements during the scanning process. Outcome measures were presence or absence of eye movements during the scanning process and mean deviation from the intended scan position, measured in millimeter. 7 of 20 patients showed no eye movements in both eyes. 4 of the remaining 13 patients showed eye movements only in one eye. In the eyes with detectable movements, the mean deviation from the intended scan position was 0.2 mm in the horizontal and 0.28 mm in the vertical scans. Fundus imaging in conventional systems can be enhanced to detect artifacts due to minimal eye movements during the scanning process. In this first series with normal healthy subjects, minimal eye movements were present in the over half of the investigations. Although the distances from the intended scan positions seem to be small in normal eyes, further investigations of the phenomenon are necessary. OCT is increasingly used as the primary tool for controlling therapy in macular diseases and the extent of motion artefacts is not known. (author) [de

  2. Automatic classification of pathological myopia in retinal fundus images using PAMELA

    Science.gov (United States)

    Liu, Jiang; Wong, Damon W. K.; Tan, Ngan Meng; Zhang, Zhuo; Lu, Shijian; Lim, Joo Hwee; Li, Huiqi; Saw, Seang Mei; Tong, Louis; Wong, Tien Yin

    2010-03-01

    Pathological myopia is the seventh leading cause of blindness. We introduce a framework based on PAMELA (PAthological Myopia dEtection through peripapilLary Atrophy) for the detection of pathological myopia from fundus images. The framework consists of a pre-processing stage which extracts a region of interest centered on the optic disc. Subsequently, three analysis modules focus on detecting specific visual indicators. The optic disc tilt ratio module gives a measure of the axial elongation of the eye through inference from the deformation of the optic disc. In the texturebased ROI assessment module, contextual knowledge is used to demarcate the ROI into four distinct, clinically-relevant zones in which information from an entropy transform of the ROI is analyzed and metrics generated. In particular, the preferential appearance of peripapillary atrophy (PPA) in the temporal zone compared to the nasal zone is utilized by calculating ratios of the metrics. The PPA detection module obtains an outer boundary through a level-set method, and subtracts this region against the optic disc boundary. Temporal and nasal zones are obtained from the remnants to generate associated hue and color values. The outputs of the three modules are used as in a SVM model to determine the presence of pathological myopia in a retinal fundus image. Using images from the Singapore Eye Research Institute, the proposed framework reported an optimized accuracy of 90% and a sensitivity and specificity of 0.85 and 0.95 respectively, indicating promise for the use of the proposed system as a screening tool for pathological myopia.

  3. Factores asociados al uso de mosquiteros en el departamento de Piura, Perú.

    Directory of Open Access Journals (Sweden)

    Fernando Llanos-Zavalaga

    2005-06-01

    Full Text Available Objetivos: El presente estudio da a conocer los factores asociados al uso de mosquiteros en el departamento de Piura. Materiales y Métodos: Estudio cualitativo realizado en Febrero y Marzo del 2000 en el departamento de Piura, Perú. Los informantes clave fueron los prestadores de salud, promotores y pobladores seleccionados aleatoriamente de dos áreas (alta y mediana endemicidad, aplicándose 12 entrevistas en profundidad (EEP, una por establecimiento, bajo el principio de saturación. Según las EEP y grupos focales (GF realizados se elaboró un mapa de conocimientos. Resultados: Se identificaron como factores asociados al uso de mosquiteros: la percepción de efectividad tanto de mosquiteros convencionales como impregnados con insecticida y la educación y supervisión continua por prestadores y promotores de salud. Los factores asociados al no uso de mosquiteros fueron: la falta de conocimiento integral sobre la enfermedad, sensación de calor y asfixia para mosquiteros convencionales, efectos adversos (reacciones dérmicas y olor del insecticida, el costo de los mosquiteros y la falta de implantación de estrategias conjuntas con aspectos educativos, de soporte, participativas y de colaboración entre los servicios de salud y la comunidad. Conclusiones: No existe buen conocimiento de la enfermedad por parte de la población pero reconocen el mosquitero como una buena medida preventiva. El conocimiento en prestadores de salud, promotores y pobladores sobre los beneficios, uso adecuado y mantenimiento de los mosquiteros impregnados con insecticida fue insuficiente, siendo necesaria la capacitación continua de esta medida preventiva contra la malaria. (Rev Med Hered 2005;16:97-106.

  4. Obesidad pediátrica y factores de riesgo cardiometabólicos asociados

    Directory of Open Access Journals (Sweden)

    Lourdes María Pérez Clemente

    Full Text Available Introducción: la obesidad está asociada a eventos cardiovasculares fundamentalmente en adultos, sin embargo, los factores de riesgo cardiometabólicos, a menudo, están presentes desde la infancia y la adolescencia. Objetivo: determinar la frecuencia de factores de riesgo cardiometabólicos en niños y adolescentes obesos. Métodos: se presenta un estudio observacional, prospectivo en 202 niños y adolescentes obesos procedentes de consultas de Endocrinología de los hospitales pediátricos de La Habana, remitidos a consulta de referencia del Hospital Pediátrico Centro Habana, durante el periodo enero-2010 a enero-2012. Al total de pacientes se les realizó una encuesta de antecedentes, factores de riesgo y mediciones físicas (peso, talla, circunferencia de cintura y tensión arterial. Se determinaron niveles séricos de colesterol, triglicéridos, colesterol transportado por lipoproteínas de alta densidad, glucemia e insulina en ayunas. Se determinó microalbuminuria como marcador de daño vascular. Se identificaron los factores de riesgo cardiometabólicos, y se correlacionaron con la microalbuminuria. Se empleó el programa estadístico SPSS 13.0 para su análisis. Resultados: se encontró que los niveles bajos de colesterol transportado por lipoproteínas de alta densidad, el síndrome metabólico, la resistencia insulínica, la hipertrigliceridemia, la hipertensión arterial y la hipercolesterolemia fueron los factores de riesgo cardiometabólicos más frecuentemente asociados a la obesidad. El factor de riesgo asociado de manera significativa a la microalbuminuria fue la hipertensión arterial. Conclusiones: los factores de riesgo cardiometabólicos asociados a la obesidad pueden ser identificados en edades tempranas de la vida.

  5. Desarrollo de una escala para evaluar recursos de personalidad asociados a la resiliencia infantil

    OpenAIRE

    Lemos, Viviana; Krumm, Gabriela; Gutierrez, Marisel; Arán-Filippetti, Vanessa

    2016-01-01

    Resumen El estudio de la resiliencia, capacidad humana para sobreponerse a las adversidades, construir sobre ellas y salir fortalecido, posee una gran relevancia, dadas las implicancias que tiene en la prevención y promoción positiva del desarrollo humano. En este sentido, el objetivo de este trabajo fue evaluar de manera válida y confiable algunos de los recursos de personalidad asociados comúnmente por la literatura a la resiliencia infantil: autocontrol, empatía, prosocialidad, autoeficaci...

  6. Prevalencia de caídas en ancianos de la comunidad: factores asociados

    OpenAIRE

    Castro Martín, Estrella

    2011-01-01

    Objetivo. Conocer la prevalencia de caídas en personas mayores, sus características, consecuencias y factores asociados.Diseño. Estudio descriptivo transversal por entrevista personal. Emplazamiento. Tres Zonas Básicas de Salud de Córdoba. Participantes. 362 personas de 70 ó mas años, residentes en la comunidad, elegidas por muestreo polietápico. Mediciones. Se realizó una valoración consistente en el estudio de las caídas con un cuestionario específico de la OMS, y de su calidad de vida, con...

  7. Ideación suicida en estudiantes de medicina: prevalencia y factores asociados

    OpenAIRE

    Pinzón-Amado, Alexander; Guerrero, Sonia; Moreno, Katherine; Landínez, Carolina; Pinzón, Julie

    2013-01-01

    Introducción: Los médicos tienen mayores tasas de suicidio en comparación con la población general. Este riesgo tiende a incrementarse incluso a partir del inicio de la formación de pregrado en medicina. Existen pocos estudios que evalúen la frecuencia de conductas suicidas en estudiantes de pregrado de medicina, especialmente en Latinoamérica. Objetivo: Determinar la prevalencia de vida y factores asociados con la ideación suicida e intentos suicidas en una muestra de estudiantes de medicina...

  8. Factores familiares asociados a los Trastornos Alimentarios: una revisión

    OpenAIRE

    Ruíz Martínez, Ana Olivia; Vázquez Arévalo, Rosalía; Mancilla Díaz, Juan Manuel; Viladrich i Segués, Carme; Halley Castillo, María Elizabeth

    2013-01-01

    Desde una perspectiva multifactorial el presente trabajo es una revisión sobre los factores familiares asociados a los Trastornos de la Conducta Alimentaria (TCA), considerando las aportaciones teóricas y empíricas propuestas en artículos nacionales e internacionales. Los resultados de la búsqueda sobre TCA y familia, indican que los principales tópicos investigados son: funcionamiento familiar, relaciones hija-padres, experiencias estresantes, psicopatología familiar, actitudes y conductas h...

  9. Cefalea por uso excesivo de analgésicos en Bucaramanga, Colombia: Prevalencia y factores asociados

    OpenAIRE

    Rueda-Sánchez, Mauricio

    2013-01-01

    Introducción : el uso de analgésicos es frecuente en pacientes con cefalea; sin embargo no hay datos sobre la prevalencia de la cefalea por uso excesivo de medicaciones (CUEM) en Colombia. Objetivo: determinar la prevalencia de CUEM en Bucaramanga-Colombia y los factores asociados a este consumo. Se realizó un estudio de prevalencia mediante un cuestionario autoadministrado en habitantes de Bucaramanga seleccionados al azar. Las comparaciones se realizaron mediante la prueba t o el chi (χ2)i ...

  10. FACTORES ASOCIADOS AL DESARROLLO DE PREECLAMPSIA EN UN HOSPITAL DE PIURA, PERÚ

    OpenAIRE

    Yamalí Benites-Cóndor; Susy Bazán-Ruiz; Danai Valladares-Garrido

    2011-01-01

    Introducción: La Organización Mundial de la Salud indica que diariamente fallecen alrededor de 800 mujeres por causas relacionadas al embarazo y parto, dentro de las cuales la preeclampsia ocupa el tercer lugar. Objetivo: identificar los factores asociados a preeclampsia en gestantes que fueron hospitalizadas en el Hospital de Apoyo II "Santa Rosa" de la ciudad de Piura durante el periodo junio 2010 - mayo 2011. Métodos: Se realizó un estudio descriptivo retrospectivo de casos y controles, e...

  11. IDENTIFICACIÓN MOLECULAR DE MICROORGANISMOS ASOCIADOS A LA RIZOSFERA DE PLANTAS DE VAINILLA EN COLOMBIA

    OpenAIRE

    CLAUDIA L. ÁLVAREZ LÓPEZ; NELSON W. OSORIO VEGA; MAURICIO MARÍN MONTOYA

    2013-01-01

    El cultivo de vainilla es altamente promisorio en Colombia, pero se requiere mayor conocimiento de su manejo agronómico y de los microorganismos que crecen asociados a su rizosfera, de los cuales depende esta planta para su nutrición y crecimiento. En este trabajo se realizaron aislamientos de microorganismos de la rizosfera de plantas de vainilla en un cultivo piloto ubicado en el municipio de Sopetrán (Antioquia, Colombia). Los microorganismos se aislaron en medios selectivos de crecimiento...

  12. Factores asociados a la utilización de servicios de salud odontológicos

    OpenAIRE

    Dho, María Silvina

    2018-01-01

    Resumen El presente trabajo se propone analizar los factores asociados a la utilización de servicios de salud odontológicos (USSO) en individuos adultos de la Ciudad de Corrientes; Argentina. Se realizó un estudio transversal. A través de una encuesta domiciliaria se recolectó información de las variables de estudio. Se determinó el tamaño de la muestra estableciéndose un nivel de confianza del 95% (381 individuos). Se aplicó un diseño muestral aleatorio simple, que se complementó con un mues...

  13. Prevalencia y factores asociados al síndrome de sobrecarga del cuidador primario de ancianos*

    OpenAIRE

    Doris Cardona A; Ángela M. Segura C; Dedsy Y. Berbesí F; María A. Agudelo M

    2013-01-01

    El síndrome de sobrecarga del cuidador de los adultos mayores es un estado de angustia que amenaza la salud física y mental por la dificultad persistente de cuidar a un familiar. Objetivo: identificar la prevalencia y factores asociados a sobrecarga en el cuidador primario de ancianos. Metodología: estudio descriptivo transversal, con 310 cuidadores principales de adultos mayores de 65 años y más de edad, seleccionados por muestreo aleatorio simple y entrevistados telefónicamente. Se calculó ...

  14. Prevalencia y factores asociados al síndrome de sobrecarga del cuidador primario de ancianos

    OpenAIRE

    Cardona A., Doris; Segura C., Ángela M.; Berbesí F., Dedsy Y.; Agudelo M., María A.

    2013-01-01

    El síndrome de sobrecarga del cuidador de los adultos mayores es un estado de angustia que amenaza la salud física y mental por la dificultad persistente de cuidar a un familiar. OBJETIVOS: identificar la prevalencia y factores asociados a sobrecarga en el cuidador primario de ancianos. METODOLOGIA:estudio descriptivo transversal, con 310 cuidadores principales de adultos mayores de 65 años y más de edad, seleccionados por muestreo aleatorio simple y entrevistados telefónicamente. Se calculó ...

  15. Xantomas eruptivos asociados a diabetes mellitus tipo II e hipertrigliceridemia: reporte de un caso

    OpenAIRE

    Victoria Bárzaga, Héctor Oscar; Ramos Cabrera, Asmell; Lazo Sánchez, Laura

    2009-01-01

    Se reporta el caso de un hombre de raza blanca, 37 años de edad, hijo de madre con diabetes mellitus tipo 1, con antecedentes patológicos personales de padecer de obesidad exógena desde aproximadamente cinco años. Comenzó a presentar de forma diseminada una erupción papulosa de color amarillento, que se diagnosticó clínicamente e histológicamente como xantomas eruptivos asociados a diabetes mellitus tipo 2 de debut e hipertrigliceridemia. Se describen las generalidades de los xantomas eruptiv...

  16. Factores asociados a la deserción de estudiantes universitarios

    OpenAIRE

    Castañeda Castañeda, Rafael Serafín

    2013-01-01

    Adopta el modelo de Vincent Tinto para analizar la deserción parcial, temporal y definitiva de estudiantes de las carreras profesionales de: Contabilidad y Finanzas, Administración Finanzas y Negocios Globales, Derecho Corporativo, Psicología, Ciencias de la Comunicación, Marketing y Negocios Globales e Ingeniería de Sistemas e Informática en la modalidad virtual de la Universidad Privada TELESUP, Lima-Perú. El objetivo de este estudio fue verificar de qué manera los factores asociados fueron...

  17. Aplicación de microorganismos asociados a biopelículas

    Directory of Open Access Journals (Sweden)

    Sergio Olarte Avellaneda

    2012-07-01

    Full Text Available Las biopelículas son comunidades microbianas y su formación ocurre por un sistema de comunicación celular conocido como Quorum sensing en el cual conforman una matriz que les confiere una mayor resistencia frente al medio; por eso, el estudio de los microorganismos asociados a biopelícula se postula como una estrategia interesante para ser utilizados en procesos de biorremediación y en este caso en la búsqueda de alternativas para la consolidación de un tratamiento secundario de aguas residuales.

  18. Factores asociados a mastitis en vacas de la microcuenca lechera del altiplano norte de Antioquia, Colombia

    OpenAIRE

    Ramírez Vásquez, Nicolás; Arroyave Henao, Ofelia; Cerón-Muñoz, Mario; Jaramillo, Manuel; Cerón, Juan; Palacio, Luis Guillermo

    2011-01-01

    Se efectuó un estudio de corte sobre la prevalencia de mastitis bovina en una muestra representativa de las granjas lecheras del altiplano norte de Antioquia, Colombia. Se evaluaron los resultados del California Mastitis Test (CMT), Recuento de Células Somáticas (RCS) y cultivo bacteriológico de leche, y se analizaron los factores de riesgo asociados a mastitis bovina. El análisis estadístico de la información se efectuó por medio de estadística descriptiva, análisis de razón de prevalencias ...

  19. Factores asociados con lactancia materna exclusiva hasta el sexto mes en madres adolescentes. medellin, 2010

    OpenAIRE

    Gómez Aristizábal, Liliana Yanet; Díaz Ruíz, Carlos Eduardo; Manrique Hernández, Ruben Dario

    2013-01-01

    Objetivo Determinar los factores asociados con la lactancia materna exclusiva hasta el sexto mes en madres adolescentes de los niveles I y II del SISBEN de la ciudad de Medellín.Métodos Se realizó un estudio de casos y controles con 323 madres adolescentes, 197 casos y 126 controles de la “Estrategia Buen Comienzo Había una Vez-BCHV” de Metrosalud y la Alcaldía de Medellín. Se aplicó estadística descriptiva para el análisis univariado. Se hizo un análisis de correspondencias. La comparación d...

  20. Frecuencia de criptorquidia y factores asociados en recién nacidos

    OpenAIRE

    Chirinos M, Jorge Luis; Gómez P, Roald E; Osuna C, Jesús A; Arata-Bellabarba, Gabriela

    2009-01-01

    Objetivos: Determinar la frecuencia de las anormalidades del descenso testicular y los factores asociados en recién nacidos (RN). Métodos: Se realizó un estudio clínico observacional tipo caso control. Durante el período noviembre 2007- Agosto 2008, se examinaron en el Instituto Autónomo Hospital Universitario de los Andes (IAHULA) todos los RN con criptorquidia, los cuales se compararon con 105 RN sin criptorquidia (grupo control). Datos complementarios fueron obtenidos mediante una encuesta...

  1. Frecuencia de criptorquidia y factores asociados en recién nacidos

    OpenAIRE

    Chirinos, Jorge; Gómez Pérez, Roald; Osuna Ceballos, Jesús A.; Arata de Bellabarba, Gabriela

    2009-01-01

    Objetivos: Determinar la frecuencia de las anormalidades del descenso testicular y los factores asociados en recién nacidos (RN). Métodos: Se realizó un estudio clínico observacional tipo caso control. Durante el período noviembre 2007-Agosto 2008, se examinaron en el Instituto Autónomo Hospital Universitario de los Andes (IAHULA) todos los RN con criptorquidia, los cuales se compararon con 105 RN sin criptorquidia (grupo control). Datos complementarios fueron obtenidos mediante una encue...

  2. Frecuencia y factores asociados al acoso escolar en colegios públicos

    OpenAIRE

    Natalia Isabel Buendía Giraldo; José Jaime Castaño Castrillón; Sandra Constanza Cañón; Jhon Alexander Giraldo Acevedo; Lucia Marín Echeverri; Sebastián Sánchez Pacheco; Fabio Alexander Suarez Ruiz

    2016-01-01

    El presente estudio tuvo como objetivo identificar la frecuencia del acoso y ciberacoso escolar y los factores asociados en una muestra representativa de 475 estudiantes de secundaria en tres instituciones públicas del municipio de Chinchiná, en el departamento de Caldas, Colombia, en el año 2014. La población fue seleccionada mediante un muestreo probabilístico estratificado por grado y género. Aplicamos las escalas: APGAR familiar, CAGE (Cut, Annoyed, Guilty, Eye), Escala Hospitalaria de An...

  3. Frecuencia y factores asociados al acoso escolar en colegios de Chinchiná (Colombia), 2014

    OpenAIRE

    Natalia Isabel, Buendía Giraldo; Castaño Castrillón, José Jaime M.Sc.; Cañón, Sandra Constanza MGTH; Giraldo Acevedo, Jhon Alexander; Echeverri, Lucia Marín; Sánchez Pacheco, Sebastián; Suarez Ruiz, Fabio Alexander

    2015-01-01

    Objetivo. Identificar la frecuencia de acoso y ciberacoso escolar y los factores asociados en una muestra representativa de 475 estudiantes de secundaria en 3 instituciones públicas de Chinchiná (Colombia) en el año 2014. Materiales y métodos: Estudio de corte transversal que se realiza en tres instituciones educativas públicas de Chinchiná-Caldas. La población está constituida por 2 330 estudiantes de secundaria, muestra 475 estudiantes. Se aplican las escalas APGAR familiar, CAG...

  4. Significado del trabajo y estrés percibido en cuidados paliativos:factores asociados

    OpenAIRE

    Moreno Milán, Beatriz

    2015-01-01

    El equilibrio entre la vida personal y profesional es un reto constante. En profesionales de cuidados paliativos este equilibrio puede ser especialmente difícil debido a las demandas propias de este trabajo. Nuestra investigación ha tratado de profundizar en el conocimiento de los recursos personales que pueden estar asociados para lograrlo. Nuestro estudio investigó el grado de interrelación entre el significado del trabajo y el nivel de estrés percibido, así como otros recursos personales c...

  5. Identificación del Burnout asociado a profesiones sanitarias y del retail

    OpenAIRE

    Díez Piñol, Miriam

    2015-01-01

    La tesis "Identificación del Burnout asociado a profesiones sanitarias y del retail" ha sido el resultado del trabajo de investigación iniciando en el 2002, con el propósito de llevar a cabo investigaciones en el ámbito de la salud y calidad de vida en el trabajo. A lo largo de casi una década fui orientando mi actividad investigadora en esta dirección, combinando distintas actividades de investigación (estudio y análisis, publicación de artículos y asistencia a eventos científicos). A partir...

  6. Factores de riesgo asociados a osteopenia del prematuro en una terapia intensiva neonatal de referencia

    OpenAIRE

    MP Ríos-Moreno; MP Salinas-López ,; NB Pérez-Ornelas ,; TL Barajas-Serrano; JC Barrera-de León

    2016-01-01

    INTRODUCCIÓN: la enfermedad ósea metabólica del prematuro resulta de la desmineralización ósea. Existen factores que deben vigilarse con la finalidad de realizar diagnóstico y tratamiento temprano. OBJETIVO: determinar los factores de riesgo asociados a osteopenia en prematuros. MATERIALES Y MÉTODOS: estudio transversal comparativo de octubre del 2011 a octubre del 2013. Se incluyeron 120 prematuros < 37 semanas gestacionales, ≤ 1,500 gramos al nacer y ≥ 21 días. Diagnóstico de la enf...

  7. Factores de riesgo asociados con malnutrición por exceso en adolescentes

    OpenAIRE

    David Yunior Velasco Peña; Osmany Álvarez Paneque; Yamilé Marí Nin; Andrés Andrés; Carlos Padilla Sánchez; Sonia Caballero Cáceres

    2012-01-01

    Introducción: en la actualidad la obesidad y el sobrepeso son un importante problema de salud para los niños y adolescentes cubanos. Objetivo: determinar algunos factores de riesgo asociados con malnutrición por exceso en adolescentes del policlínico Julio Grave de Peralta de la provincia Holguín durante el periodo de agosto del 2011 a febrero del 2012. Métodos: se realizó un estudio analítico y transversal. Se estudiaron 37 adolescentes entre 15-19 años. Las variables analizadas en el estu...

  8. Factores personales y familiares asociados a los problemas de comportamiento en niños

    OpenAIRE

    Rodríguez,María Clara

    2010-01-01

    Se identificaron los factores personales y familiares asociados a los problemas de comportamiento en niños. Participaron 254 escolares, entre 7 y 11 años, sus respectivos padres y docentes. Una vez obtenido el consentimiento informado, se aplicaron la Escala Multidimensional de la Conducta de Reynolds y Kamphaus; estandarizada en Medellín, Cuestionario de Evaluación de factores personales y familiares. El análisis chi-cuadrado muestra que la inconsistencia en las pautas de crianza, no vivir c...

  9. EFECTOS DE LA METFORMINA EN EL SINDROME DE OVARIO POLIQUISTICO ASOCIADO A INSULINO RESISTENCIA

    OpenAIRE

    Caro,Claudio; Fuhrer,Juan; Sáez,Rodrigo; Rubio,Víctor; Moreno,Luis; Cumsille,Miguel

    2002-01-01

    Se presenta la experiencia clínica del uso de metformina (1,7 g día), por 4 meses, en 11 pacientes con (SOP) asociado a resistencia insulínica. Se determinaron los efectos clínicos, bioquímicos y hormonales luego de 4 meses de terapia. Cinco de las pacientes que deseaban embarazo, continuaron recibiendo la droga, hasta por un año. Se evaluó durante el tratamiento los síntomas clínicos, historia menstrual, hirsutismo; y los niveles séricos de gonadotrofinas, andrógenos, globulina ligante sexua...

  10. Factores asociados y consecuencias clínicas de la anemia post trasplante renal

    OpenAIRE

    Mónica Freiberg; Carlos Chiurchiu; Raúl Capra; Andrea Eckhardt; Jorge de la Fuente; Walter Douthat; Javier de Arteaga; Pablo U. Massari

    2013-01-01

    Un porcentaje considerable de pacientes presentan anemia post trasplante renal. Su origen es multifactorial y sus principales etiologías dependen de la etapa post trasplante que se considere. Estudiamos en un grupo de 134 pacientes los factores asociados con anemia tardía (6 meses post trasplante) y sus implicaciones clínicas a mediano plazo. En el análisis de regresión múltiple, la duración de la oliguria post trasplante y el número de episodios de rechazo fueron las variables significativam...

  11. Nivel de autoestima y factores asociados en adolescentes escolarizados en la parroquia Paccha, Cuenca- Azuay 2015.

    OpenAIRE

    Zambrano Faicán, Viviana Paola

    2017-01-01

    Antecedentes: Una autoestima elevada se asocia con bienestar, buen rendimiento académico, entre otras condiciones favorables para el individuo. Sin embargo, en la actualidad aún no están completamente claros los factores que determinan el desarrollo de la autoestima en los individuos. Objetivos: Determinar el nivel de autoestima y su relación con los factores asociados en los adolescentes escolarizados de la parroquia Paccha, Cuenca – Azuay. Materiales y Métodos: Se llevó a cabo un est...

  12. Función endotelial y lipemia postprandial en adultos con presencia de criterios asociados a síndrome metabólico: efecto del estado nutricional

    Directory of Open Access Journals (Sweden)

    Diana Milena Díaz-Vidal

    2017-07-01

    Conclusión: Este estudio demuestra que los sujetos clasificados en sobrepeso y que presentan criterios asociados al síndrome metabólico, muestran un perfil cardiometabólico asociado con un mayor riesgo cardiovascular, tras una ingesta alta en grasas.

  13. Tercerización y cooperativas de trabajo asociado en el hospital San Rafael de Tunja

    Directory of Open Access Journals (Sweden)

    Lina Marleny López Sánchez

    2010-06-01

    Full Text Available En este documento se destacan los diversos efectos que el funcionamiento de las Cooperativas de Trabajo Asociado (CTA ha traído en la contratación de personal del Hospital San Rafael de Tunja, a partir de la reestructuración registrada a finales del año 2004. Así mismo, se enfatiza en el cómo la tercerización ha venido adquiriendo importancia en este tipo de instituciones hospitalarias, mediante la prestación de servicios médico-asistenciales,administrativos y servicios generales, lo que revela que la contratación incluyó actividades misionales no inherentes a la naturaleza de la tercerización. Por último, se analiza el cumplimiento de los principios cooperativos (definidos por el Congreso Alianza Cooperativa Internacional en 1995 y adaptados por Confecoop, por parte de las cooperativas de trabajo asociado que suministran los servicios requeridos por el hospital.

  14. Invertebrados acuáticos asociados a la Bromelia Tillandsia turneri Baker. en un bosque altoandino

    Directory of Open Access Journals (Sweden)

    María Fabiola Ospina

    2000-07-01

    Full Text Available Las bromelias como plantas fitotelmas mantienen una compleja cadena trófica que incluye invertebrados asociados a depósitos de agua. Se determinó la comunidad de invertebrados acuáticos de la bromelia Tillandsia turneri en un bosque altoandino en el Municipio de Chocontá, Cundinamarca, Colombia. Se estudiaron 37 individuos de la bromelia ubicadas desde 0 hasta 6 m de altura, a las cuales se realizaron mediciones morfológicas, de contenido de agua y análisis fisicoquímico de esta y se colectaron los invertebrados asociados. Los órdenes mas abundantes fueron Coleóptera, Díptera y Cladócera; por medio de un análisis de similaridad de Morisita Horn se encontró que las bromelias son similares en cuanto a composición de invertebrados, por lo que se sugiere que pertenecen a un solo estrato dentro del bosque y que los procesos de ovoposición y dispersión para los grupos estudiados tienen igual probabilidad de ocurrir en las bromelias ubicadas de 0 a 6 m de altura.

  15. Frecuencia y factores asociados al acoso escolar en colegios públicos

    Directory of Open Access Journals (Sweden)

    Natalia Isabel Buendía Giraldo

    2016-01-01

    Full Text Available El presente estudio tuvo como objetivo identificar la frecuencia del acoso y ciberacoso escolar y los factores asociados en una muestra representativa de 475 estudiantes de secundaria en tres instituciones públicas del municipio de Chinchiná, en el departamento de Caldas, Colombia, en el año 2014. La población fue seleccionada mediante un muestreo probabilístico estratificado por grado y género. Aplicamos las escalas: APGAR familiar, CAGE (Cut, Annoyed, Guilty, Eye, Escala Hospitalaria de Ansiedad y Depresión (HAD, la SCOFF (Scik Control On Fast Food, el acoso escolar por medio de la encuesta sobre convivencia escolar para alumnos, y el ciberacoso por medio de Escala de Patchin. De acuerdo al cuestionario empleado se encontró una proporción del más alto nivel de acoso del 1.9%, 0.4% acosadores, 1.3% ciberacoso, 1.9% ciberacosadores, en rango medio, 14% acoso, 8.5% acosador, 5.5% ciberacoso, 4.9% ciberagresores. Se encontraron relaciones significativas entre nivel de acoso y funcionalidad familiar, consumo de alcohol, ansiedad, depresión, consumo de sustancias, nivel de ciberacoso también con trastornos de la conducta alimentaria. Los factores asociados con acoso y ciberacoso afectan por igual a acosados y acosadores, resultado también encontrado en otros estudios. En esta población se presentan principalmente niveles de acoso medio y bajo.

  16. Factores asociados a recaídas por tuberculosis en Lima este - Perú

    Directory of Open Access Journals (Sweden)

    María Ríos Hipólito

    2002-01-01

    Full Text Available Objetivo: Determinar los factores de riesgo asociados a recaídas por tuberculosis en Lima Este - Perú, entre marzo y diciembre del 2000. Materiales y métodos: estudio caso-control. Se definió a los casos (184 como los pacientes que recibieron tratamiento con el esquema I alguna vez, egresaron como curados y volvieron a presentar otro episodio de tuberculosis BK positivo durante 1999. Los controles (368 fueron los pacientes nuevos con tuberculosis BK positivo tratados en 1998 que no recayeron. Resultados: se asociaron significativamente a las recaídas el sexo masculino, la edad mayor de 50 años, el consumo de drogas, la residencia en un área urbana, el hacinamiento, la percepción errada de la enfermedad (PEE y la desocupación, no así el contacto con un paciente tuberculoso. Luego del análisis multivariado, sólo se asociaron el área urbana, el hacinamiento, la PEE y el tratamiento irregular. Conclusiones: la residencia en un área urbana, el hacinamiento, la PEE y la irregularidad en el tratamiento son factores asociados significativamente a recaídas en pacientes con TBC pulmonar BK(+ de Lima Este, Perú.

  17. Factores asociados al abandono del tratamiento antituberculoso en pacientes con TB

    Directory of Open Access Journals (Sweden)

    Cecilia Navarro-Quintero

    2013-06-01

    Full Text Available Objetivo. Determinar los factores asociados al abandono del tratamiento antituberculoso, en pacientes de tuberculosis en los municipios de Cúcuta, Villa del Rosario y el Zulia. Materiales y Métodos: estudio cuantitativo de tipo descriptivo retrospectivo transversal de corte con dos muestras, donde se analizó una muestra de abandono al tratamiento (n=34 y otra que terminó el tratamiento antituberculoso (n=34. Se adoptó el instrumento “factores asociados al abandono del tratamiento antituberculoso. Resultados: Los factores perceptivos cognitivos se establecieron como los principales determinantes directos de abandono al tratamiento antituberculoso, entre estos en primer lugar el desconocimiento de la importancia de adherencia al tratamiento (95.8%, seguido de mejoría del estado de salud (82.7%, desconocimiento de la duración del tratamiento (75%. En segundo lugar los factores fisiológicos y por último los factores de seguridad. Conclusiones: el estudio permitió identificar las variables asociadas al abandono del tratamiento antituberculoso, clasificar los factores de riesgo y construir un instrumento al implementarse en los servicios de salud de la región, permitiría al personal de salud detectar oportunamente a los pacientes con un posible riesgo.

  18. Quantitative Fundus Autofluorescence in Best Vitelliform Macular Dystrophy: RPE Lipofuscin is not Increased in Non-Lesion Areas of Retina.

    Science.gov (United States)

    Sparrow, Janet R; Duncker, Tobias; Woods, Russell; Delori, François C

    2016-01-01

    Since the lipofuscin of retinal pigment epithelial (RPE) cells has been implicated in the pathogenesis of Best vitelliform macular dystrophy, we quantified fundus autofluorescence (quantitative fundus autofluorescence, qAF) as an indirect measure of RPE lipofuscin levels. Mean non-lesion qAF was found to be within normal limits for age. By spectral domain optical coherence tomography (SD-OCT) vitelliform lesions presented as fluid-filled subretinal detachments containing reflective material. We discuss photoreceptor outer segment debris as the source of the intense fluorescence of these lesions and loss of anion channel functioning as an explanation for the bullous photoreceptor-RPE detachment. Unexplained is the propensity of the disease for central retina.

  19. A Method of Drusen Measurement Based on the Geometry of Fundus Reflectance

    Directory of Open Access Journals (Sweden)

    Barbazetto Irene

    2003-04-01

    Full Text Available Abstract Background The hallmarks of age-related macular degeneration, the leading cause of blindness in the developed world, are the subretinal deposits known as drusen. Drusen identification and measurement play a key role in clinical studies of this disease. Current manual methods of drusen measurement are laborious and subjective. Our purpose was to expedite clinical research with an accurate, reliable digital method. Methods An interactive semi-automated procedure was developed to level the macular background reflectance for the purpose of morphometric analysis of drusen. 12 color fundus photographs of patients with age-related macular degeneration and drusen were analyzed. After digitizing the photographs, the underlying background pattern in the green channel was leveled by an algorithm based on the elliptically concentric geometry of the reflectance in the normal macula: the gray scale values of all structures within defined elliptical boundaries were raised sequentially until a uniform background was obtained. Segmentation of drusen and area measurements in the central and middle subfields (1000 μm and 3000 μm diameters were performed by uniform thresholds. Two observers using this interactive semi-automated software measured each image digitally. The mean digital measurements were compared to independent stereo fundus gradings by two expert graders (stereo Grader 1 estimated the drusen percentage in each of the 24 regions as falling into one of four standard broad ranges; stereo Grader 2 estimated drusen percentages in 1% to 5% intervals. Results The mean digital area measurements had a median standard deviation of 1.9%. The mean digital area measurements agreed with stereo Grader 1 in 22/24 cases. The 95% limits of agreement between the mean digital area measurements and the more precise stereo gradings of Grader 2 were -6.4 % to +6.8 % in the central subfield and -6.0 % to +4.5 % in the middle subfield. The mean absolute

  20. EVALUATION OF DIABETIC MACULAR OEDEMA WITH SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHY AND FUNDUS FLUORESCEIN ANGIOGRAPHY

    Directory of Open Access Journals (Sweden)

    Mallika Venkitasubramanian

    2017-02-01

    Full Text Available BACKGROUND Macular oedema is an important cause of visual morbidity in Diabetic Retinopathy. It can be assessed by both Fundus Fluorescein Angiography (FFA and Optical Coherence Tomography (OCT. The aims of this study were to evaluate the agreement between morphological features on spectral domain Optical Coherence Tomography and Fluorescein Angiographic leakage patterns in Diabetic Macular Oedema, and to study the correlation between the best corrected visual acuity and central foveal thickness measured by Optical Coherence Tomography. MATERIALS AND METHODS This was an observational study. All patients with Diabetic Macular Oedema underwent complete ophthalmic examination and subjected to FFA and OCT. Presence or absence of macular oedema by FFA and OCT was noted and agreement between two modalities of imaging was assessed. Sensitivity of these modalities were also found out using appropriate statistical methods. Best Corrected Visual Acuity (BCVA measured were converted to LogMAR scale and Central foveal thickness measured by OCT. Linear regression analysis was done with central foveal thickness and LogMAR visual acuity. RESULTS A total of 69 eyes of 39 patients were studied. OCT revealed Diabetic Macular Oedema in 97.5% of eyes. Fundus Fluorescein Angiography performed in these patients identified leakage in 95.6% of eyes. Sensitivity and specificity of FFA and OCT were calculated keeping one as the gold standard for sensitivity and specificity of the other. FFA and OCT had almost equal sensitivity (95.46 for OCT and 96.92 for FFA for detection of DME. Specificity of OCT was found to be slightly higher (33.33% compared to FFA (25%. Our results suggest that there is minimal agreement between these two imaging modalities in evaluating DME. Statistically, Kappa value was 0.248. Linear regression analysis showed that central foveal thickness had a significant correlation with visual acuity, with Pearson correlation coefficient r=0.442, p=0

  1. Cost effectiveness of a telephone intervention to promote dilated fundus examination in adults with diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Clyde B Schechter

    2008-05-01

    Full Text Available Clyde B Schechter1, Charles E Basch2, Arlene Caban3, Elizabeth A Walker41Departments of Family and Social Medicine and Epidemiology and Population Health, Albert Einstein College of Medicine, Bronx, New York, USA; 2Department of Health Behavior Studies, Teachers College, Columbia University, New York, NY, USA; 3Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, USA; 4Departments of Medicine and Epidemiology and Population Health, Albert Einstein College of Medicine, Bronx, New York, USAAbstract: In a clinical trial, we have previously shown that a telephone intervention can significantly increase participation in dilated fundus examination (DFE screening among low-income adults with diabetes. Here the costs and cost-effectiveness ratio of this intervention are calculated. Intervention effectiveness was estimated as the difference in DFE utilization between the telephone intervention and print groups from the clinical trial multiplied by the size of the telephone intervention group. A micro-costing approach was used. Personnel time was aggregated from logs kept during the clinical trial of the intervention. Wage rates were taken from a commercial compensation database. Telephone charges were estimated based on prevailing fees. The cost-effectiveness ratio was calculated as the ratio of total costs of the intervention to the number of DFEs gained by the intervention. A sensitivity analysis estimated the cost-effectiveness of a more limited telephone intervention. A probabilistic sensitivity analysis using bootstrap samples from the clinical trial results quantified the uncertainties in resource utilization and intervention effectiveness. Net intervention costs were US$18,676.06, with an associated gain of 43.7 DFEs and 16.4 new diagnoses of diabetic retinopathy. The cost-effectiveness ratio is US$427.37 per DFE gained. A restricted intervention limiting the number of calls to 5, as opposed to 7, would achieve the same results

  2. Fundus autofluorescence in central serous chorioretinopathy:association with spectral-domain optical coherence tomography and fluorescein angiography

    Directory of Open Access Journals (Sweden)

    Peng Zhang

    2015-10-01

    Full Text Available AIM: To evaluate the correlation among changes in fundus autofluorescence (AF measured using infrared fundus AF (IR-AF and short-wave length fundus AF (SW-AF with changes in spectral-domain optical coherence tomography (SD-OCT and fluorescein angiography (FA in central serous chorioretinopathy (CSC.METHODS:Two hundred and twenty consecutive patients with CSC were included. In addition to AF, patients were assessed by means of SD-OCT and FA. Abnormalities in images of IR-AF, SW-AF, FA were analyzed and correlated with the corresponding outer retinal alterations in SD-OCT findings.RESULTS:Eyes with abnormalities on either IR-AF or SW-AF were found in 256 eyes (58.18%, among them 256 eyes (100% showed abnormal IR-AF, but SW-AF abnormalities were present only in 213 eyes (83.20%. The hypo-IR-AF corresponded to accumulation of sub-retinal liquid, collapse of retinal pigment epithelium (RPE or detachment of RPE with or without RPE leakage point in the corresponding area. The hyper-IR-AF corresponded to the area with loss of the ellipsoid portion of the inner segments and sub-sensory retinal deposits or focal melanogenesis under sensory retina. The hypo-SW-AF corresponded to accumulation of sub-retinal liquid or atrophy of RPE. The hyper-SW-AF associated with sub-sensory retinal deposits, detachment of RPE and focal melanogenesis.CONCLUSION:IR-AF was more sensitive than SW-AF and FA for identifying pathological abnormalities in CSC. The characteristics of IR-AF in CSC were attributable to the modification of melanin in the RPE. IR-AF should be used as a common diagnostic tool for identifying pathological lesion in CSC.KEYWORDS:central serous chorioretinopathy; fluorescein angiography; fundus autofluorescence; optical coherence tomography

  3. Interoperative fundus image and report sharing in compliance with integrating the healthcare enterprise conformance and web access todigital imaging and communication in medicinepersistent object protocol

    Directory of Open Access Journals (Sweden)

    Hui-Qun Wu

    2013-12-01

    Full Text Available AIM:To address issues in interoperability between different fundus image systems, we proposed a web eye-picture archiving and communication system (PACS framework in conformance with digital imaging and communication in medicine (DICOM and health level 7 (HL7 protocol to realize fundus images and reports sharing and communication through internet.METHODS: Firstly, a telemedicine-based eye care work flow was established based on integrating the healthcare enterprise (IHE Eye Care technical framework. Then, a browser/server architecture eye-PACS system was established in conformance with the web access to DICOM persistent object (WADO protocol, which contains three tiers.RESULTS:In any client system installed with web browser, clinicians could log in the eye-PACS to observe fundus images and reports. Multipurpose internet mail extensions (MIME type of a structured report is saved as pdf/html with reference link to relevant fundus image using the WADO syntax could provide enough information for clinicians. Some functions provided by open-source Oviyam could be used to query, zoom, move, measure, view DICOM fundus images.CONCLUSION:Such web eye-PACS in compliance to WADO protocol could be used to store and communicate fundus images and reports, therefore is of great significance for teleophthalmology.

  4. Interoperative fundus image and report sharing in compliance with integrating the healthcare enterprise conformance and web access to digital imaging and communication in medicine persistent object protocol.

    Science.gov (United States)

    Wu, Hui-Qun; Lv, Zheng-Min; Geng, Xing-Yun; Jiang, Kui; Tang, Le-Min; Zhou, Guo-Min; Dong, Jian-Cheng

    2013-01-01

    To address issues in interoperability between different fundus image systems, we proposed a web eye-picture archiving and communication system (PACS) framework in conformance with digital imaging and communication in medicine (DICOM) and health level 7 (HL7) protocol to realize fundus images and reports sharing and communication through internet. Firstly, a telemedicine-based eye care work flow was established based on integrating the healthcare enterprise (IHE) Eye Care technical framework. Then, a browser/server architecture eye-PACS system was established in conformance with the web access to DICOM persistent object (WADO) protocol, which contains three tiers. In any client system installed with web browser, clinicians could log in the eye-PACS to observe fundus images and reports. Multipurpose internet mail extensions (MIME) type of a structured report is saved as pdf/html with reference link to relevant fundus image using the WADO syntax could provide enough information for clinicians. Some functions provided by open-source Oviyam could be used to query, zoom, move, measure, view DICOM fundus images. Such web eye-PACS in compliance to WADO protocol could be used to store and communicate fundus images and reports, therefore is of great significance for teleophthalmology.

  5. Retinal pigment epithelial changes in chronic Vogt-Koyanagi-Harada disease: fundus autofluorescence and spectral domain optical coherence tomography findings

    Science.gov (United States)

    Vasconcelos-Santos, Daniel V.; Sohn, Elliott H.; Sadda, Srinivas; Rao, Narsing A.

    2009-01-01

    Purpose To determine whether fundus autofluorescence (FAF) and spectral-domain optical coherence tomography (SD-OCT) imaging allows better assessment of RPE and outer retina (OR) in subjects with chronic VKH compared to examination and angiography alone. Methods Cross-sectional analysis of a series of seven consecutive patients with chronic VKH undergoing FAF and SD-OCT. Chronic VKH was defined as during >3 months. Color fundus photographs were correlated to FAF and SD-OCT images. The images were later correlated to fluorescein angiography (FA) and indocyanine green angiography (ICG-A). Results All patients had sunset glow fundus, which resulted in no apparent corresponding abnormality on FAF or SD-OCT. Lesions with decreased autofluorescence signal were observed in 11 eyes (85%), being associated with loss of the RPE and involvement of OR on SD-OCT. In 5 eyes (38%) some of these lesions were very subtle on clinical examination but easily detected by FAF. Lesions with increased autofluorescence signal were seen in 8 eyes (61.5%), showing variable involvement of the OR on SD-OCT and corresponding clinically to areas of RPE proliferation and cystoid macular edema. Conclusion Combined use of FAF and SD-OCT imaging allowed noninvasive delineation of RPE/OR changes in patients with chronic VKH, which were consistent with previous histopathological reports. Some of these changes were not apparent on clinical examination. PMID:20010321

  6. Agreement between clinical estimation and a new quantitative analysis by Photoshop software in fundus and angiographic image variables.

    Science.gov (United States)

    Ramezani, Alireza; Ahmadieh, Hamid; Azarmina, Mohsen; Soheilian, Masoud; Dehghan, Mohammad H; Mohebbi, Mohammad R

    2009-12-01

    To evaluate the validity of a new method for the quantitative analysis of fundus or angiographic images using Photoshop 7.0 (Adobe, USA) software by comparing with clinical evaluation. Four hundred and eighteen fundus and angiographic images of diabetic patients were evaluated by three retina specialists and then by computing using Photoshop 7.0 software. Four variables were selected for comparison: amount of hard exudates (HE) on color pictures, amount of HE on red-free pictures, severity of leakage, and the size of the foveal avascular zone (FAZ). The coefficient of agreement (Kappa) between the two methods in the amount of HE on color and red-free photographs were 85% (0.69) and 79% (0.59), respectively. The agreement for severity of leakage was 72% (0.46). In the two methods for the evaluation of the FAZ size using the magic and lasso software tools, the agreement was 54% (0.09) and 89% (0.77), respectively. Agreement in the estimation of the FAZ size by the lasso magnetic tool was excellent and was almost as good in the quantification of HE on color and on red-free images. Considering the agreement of this new technique for the measurement of variables in fundus images using Photoshop software with the clinical evaluation, this method seems to have sufficient validity to be used for the quantitative analysis of HE, leakage, and FAZ size on the angiograms of diabetic patients.

  7. Modified submucosal tunneling endoscopic resection for submucosal tumors in the esophagus and gastric fundus near the cardia.

    Science.gov (United States)

    Zhang, Qiang; Cai, Jian-Qun; Xiang, Li; Wang, Zhen; de Liu, Si; Bai, Yang

    2017-08-01

    Background and study aims  Submucosal tunneling endoscopic resection with double opening (DO-STER) was developed by our group for the resection of submucosal tumors in the esophagus and gastric fundus near the cardia. This study aimed to provide a preliminary evaluation of feasibility and safety of DO-STER. Methods  The key to DO-STER is the creation of a tunnel opening in the mucosa over the inferior border of the tumor. During resection, the tumor can be gradually pushed out of the submucosal tunnel through the opening, leaving enough space for operation within the tunnel. A total of 10 tumors resected by DO-STER were retrospectively reviewed. Results  All tumors were successfully resected by DO-STER. One tumor was located at the lower esophagus, four at the esophagogastric junction, and five at the gastric fundus near the cardia. Tumor size ranged from 1.0 × 1.2 cm to 3.5 × 5.0 cm, and all tumors originated from the muscularis propria. Operative times ranged from 45 to 150 minutes. No delayed bleeding or perforation occurred. Conclusion DO-STER seems to provide an alternative approach for resection of tumors in the esophagus and gastric fundus near the cardia. © Georg Thieme Verlag KG Stuttgart · New York.

  8. Diabetic Retinopathy Screening Ratio Is Improved When Using a Digital, Nonmydriatic Fundus Camera Onsite in a Diabetes Outpatient Clinic

    Directory of Open Access Journals (Sweden)

    Pia Roser

    2016-01-01

    Full Text Available Objective. To evaluate the effect of onsite screening with a nonmydriatic, digital fundus camera for diabetic retinopathy (DR at a diabetes outpatient clinic. Research Design and Methods. This cross-sectional study included 502 patients, 112 with type 1 and 390 with type 2 diabetes. Patients attended screenings for microvascular complications, including diabetic nephropathy (DN, diabetic polyneuropathy (DP, and DR. Single-field retinal imaging with a digital, nonmydriatic fundus camera was used to assess DR. Prevalence and incidence of microvascular complications were analyzed and the ratio of newly diagnosed to preexisting complications for all entities was calculated in order to differentiate natural progress from missed DRs. Results. For both types of diabetes, prevalence of DR was 25.0% (n=126 and incidence 6.4% (n=32 (T1DM versus T2DM: prevalence: 35.7% versus 22.1%, incidence 5.4% versus 6.7%. 25.4% of all DRs were newly diagnosed. Furthermore, the ratio of newly diagnosed to preexisting DR was higher than those for DN (p=0.12 and DP (p=0.03 representing at least 13 patients with missed DR. Conclusions. The results indicate that implementing nonmydriatic, digital fundus imaging in a diabetes outpatient clinic can contribute to improved early diagnosis of diabetic retinopathy.

  9. Retinal blood vessel segmentation in high resolution fundus photographs using automated feature parameter estimation

    Science.gov (United States)

    Orlando, José Ignacio; Fracchia, Marcos; del Río, Valeria; del Fresno, Mariana

    2017-11-01

    Several ophthalmological and systemic diseases are manifested through pathological changes in the properties and the distribution of the retinal blood vessels. The characterization of such alterations requires the segmentation of the vasculature, which is a tedious and time-consuming task that is infeasible to be performed manually. Numerous attempts have been made to propose automated methods for segmenting the retinal vasculature from fundus photographs, although their application in real clinical scenarios is usually limited by their ability to deal with images taken at different resolutions. This is likely due to the large number of parameters that have to be properly calibrated according to each image scale. In this paper we propose to apply a novel strategy for automated feature parameter estimation, combined with a vessel segmentation method based on fully connected conditional random fields. The estimation model is learned by linear regression from structural properties of the images and known optimal configurations, that were previously obtained for low resolution data sets. Our experiments in high resolution images show that this approach is able to estimate appropriate configurations that are suitable for performing the segmentation task without requiring to re-engineer parameters. Furthermore, our combined approach reported state of the art performance on the benchmark data set HRF, as measured in terms of the F1-score and the Matthews correlation coefficient.

  10. Comparison of conventional color fundus photography and multicolor imaging in choroidal or retinal lesions.

    Science.gov (United States)

    Muftuoglu, Ilkay Kilic; Gaber, Raouf; Bartsch, Dirk-Uwe; Meshi, Amit; Goldbaum, Michael; Freeman, William R

    2018-04-01

    Our purpose was to compare the characteristics of the retinal and choroidal lesions including choroidal nevus, choroidal melanoma and congenital hypertrophy of the retina pigment epithelium using conventional color fundus photography (CFP) and multicolor imaging (MCI). The paired images of patients with retinal or choroidal lesions were assessed for the visibility of lesion's border, halo and drusen using a grading scale (0-2). The area of the lesion was measured on both imaging modalities. The same grading was also done on the individual color channels of MCI for a further evaluation. Thirty-three eyes of 33 patients were included. There were no significant differences in the mean border, drusen and halo visibility scores between the two imaging modalities (p = 0.12, p = 0.70, p = 0.35). However, the mean area of the lesion was significantly smaller on MCI than that on CFP (14.9±3.3 versus 18.7±3.4 mm 2 , p = 0.01). The appearance of choroidal and/ or retinal lesions on MCI may be different than that on CFP. Though MCI can provide similar information with CFP for the features of retinal and/ or choroidal lesions including border, halo and drusen; the infrared light reflection on MCI underestimates the extent of the choroidal lesion by 33%.

  11. En Face Optical Coherence Tomography Angiography Imaging Versus Fundus Photography in the Measurement of Choroidal Nevi.

    Science.gov (United States)

    Lee, Michele D; Kaidonis, Georgia; Kim, Alice Y; Shields, Ryan A; Leng, Theodore

    2017-09-01

    Choroidal nevi are common benign intraocular tumors with a small risk of malignant transformation. This retrospective study investigates the use of en face spectral-domain optical coherence tomography angiography (SD-OCTA) in determining the clinical features and measurement of choroidal nevi. Patients with choroidal nevi were imaged with both OCTA and a fundus photography device. Greatest longitudinal dimension (GLD), perpendicular dimension (PD), and the GLD/PD ratio were assessed on each device. Inter-device variation and intra- and inter-rater reliability analyses were performed. Fourteen patients with choroidal nevi were included. No significant difference between the GLD/PD ratio as measured by all three devices was found (Chi-square = 2.8, 2 df, P = .247). Intraclass correlation coefficients were greater than 0.7 for repeated measures on all devices, suggesting good repeatability and reproducibility. This study demonstrated inter-device consistency and high intra- and inter-rater reliability when measuring choroidal nevi. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:741-747.]. Copyright 2017, SLACK Incorporated.

  12. Automated retinal nerve fiber layer defect detection using fundus imaging in glaucoma.

    Science.gov (United States)

    Panda, Rashmi; Puhan, N B; Rao, Aparna; Padhy, Debananda; Panda, Ganapati

    2018-06-01

    Retinal nerve fiber layer defect (RNFLD) provides an early objective evidence of structural changes in glaucoma. RNFLD detection is currently carried out using imaging modalities like OCT and GDx which are expensive for routine practice. In this regard, we propose a novel automatic method for RNFLD detection and angular width quantification using cost effective redfree fundus images to be practically useful for computer-assisted glaucoma risk assessment. After blood vessel inpainting and CLAHE based contrast enhancement, the initial boundary pixels are identified by local minima analysis of the 1-D intensity profiles on concentric circles. The true boundary pixels are classified using random forest trained by newly proposed cumulative zero count local binary pattern (CZC-LBP) and directional differential energy (DDE) along with Shannon, Tsallis entropy and intensity features. Finally, the RNFLD angular width is obtained by random sample consensus (RANSAC) line fitting on the detected set of boundary pixels. The proposed method is found to achieve high RNFLD detection performance on a newly created dataset with sensitivity (SN) of 0.7821 at 0.2727 false positives per image (FPI) and the area under curve (AUC) value is obtained as 0.8733. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. A Web-based telemedicine system for diabetic retinopathy screening using digital fundus photography.

    Science.gov (United States)

    Wei, Jack C; Valentino, Daniel J; Bell, Douglas S; Baker, Richard S

    2006-02-01

    The purpose was to design and implement a Web-based telemedicine system for diabetic retinopathy screening using digital fundus cameras and to make the software publicly available through Open Source release. The process of retinal imaging and case reviewing was modeled to optimize workflow and implement use of computer system. The Web-based system was built on Java Servlet and Java Server Pages (JSP) technologies. Apache Tomcat was chosen as the JSP engine, while MySQL was used as the main database and Laboratory of Neuro Imaging (LONI) Image Storage Architecture, from the LONI-UCLA, as the platform for image storage. For security, all data transmissions were carried over encrypted Internet connections such as Secure Socket Layer (SSL) and HyperText Transfer Protocol over SSL (HTTPS). User logins were required and access to patient data was logged for auditing. The system was deployed at Hubert H. Humphrey Comprehensive Health Center and Martin Luther King/Drew Medical Center of Los Angeles County Department of Health Services. Within 4 months, 1500 images of more than 650 patients were taken at Humphrey's Eye Clinic and successfully transferred to King/Drew's Department of Ophthalmology. This study demonstrates an effective architecture for remote diabetic retinopathy screening.

  14. Endoscopically Assisted Drilling, Exposure of the Fundus through a Presigmoid Retrolabyrinthine Approach: A Cadaveric Feasibility Study.

    Science.gov (United States)

    Muelleman, Thomas; Shew, Matthew; Alvi, Sameer; Shah, Kushal; Staecker, Hinrich; Chamoun, Roukouz; Lin, James

    2018-01-01

    The presigmoid retrolabyrinthine approach to the cerebellopontine angle is traditionally described to not provide access to the internal auditory canal (IAC). We aimed to evaluate the extent of the IAC that could be exposed with endoscopically assisted drilling and to measure the percentage of the IAC that could be visualized with the microscope and various endoscopes after drilling had been completed. Presigmoid retrolabyrinthine approaches were performed bilaterally on 4 fresh cadaveric heads. We performed endoscopically assisted drilling to expose the fundus of the IAC, which resulted in exposure of the entire IAC in 8 of 8 temporal bone specimens. The microscope afforded a mean view of 83% (n = 8) of the IAC. The 0°, 30°, 45°, and 70° endoscope each afforded a view of 100% of the IAC in 8 of 8 temporal bone specimens. In conclusion, endoscopic drilling of the IAC of can provide an extradural means of exposing the entire length of the IAC while preserving the labyrinth.

  15. A thresholding based technique to extract retinal blood vessels from fundus images

    Directory of Open Access Journals (Sweden)

    Jyotiprava Dash

    2017-12-01

    Full Text Available Retinal imaging has become the significant tool among all the medical imaging technology, due to its capability to extract many data which is linked to various eye diseases. So, the accurate extraction of blood vessel is necessary that helps the eye care specialists and ophthalmologist to identify the diseases at the early stages. In this paper, we have proposed a computerized technique for extraction of blood vessels from fundus images. The process is conducted in three phases: (i pre-processing where the image is enhanced using contrast limited adaptive histogram equalization and median filter, (ii segmentation using mean-C thresholding to extract retinal blood vessels, (iii post-processing where morphological cleaning operation is used to remove isolated pixels. The performance of the proposed method is tested on and experimental results show that our method achieve an accuracies of 0.955 and 0.954 on Digital retinal images for vessel extraction (DRIVE and Child heart and health study in England (CHASE_DB1 databases respectively.

  16. Effect of chronic aspirin ingestion on epithelial proliferation in rat fundus, antrum, and duodenum

    International Nuclear Information System (INIS)

    Eastwood, G.L.; Quimby, G.F.

    1972-01-01

    We studied the effect of chronic aspirin ingestion on gastroduodenal epithelial proliferation by feeding rats aspirin in the drinking water. A control group of rats received plain water. At the end of 4 wk, [3H]-thymidine was given intravenously to label proliferating cells, and the rats were killed 1 h later. Sections of fundus, antrum, and proximal duodenum were processed for light autoradiography. We found that chronic aspirin ingestion stimulated epithelial proliferation in fundic mucosa but had no effect in the antrum. In the duodenum, aspirin increased proliferation in the lowest four crypt-cell positions, which most likely indicates an increase in stem-cell production. None of the tissues contained evidence of inflammation or ulceration. The proliferative effects of aspirin may help explain the previously observed phenomenon of mucosal adaptation in the rat after repeated exposure to aspirin. Further, if human gastroduodenal epithelium responds in a similar manner to chronic aspirin exposure, the effects on proliferation may explain in part the distribution of aspirin-associated ulcers

  17. Structural and functional changes associated with normal and abnormal fundus autofluorescence in patients with retinitis pigmentosa.

    Science.gov (United States)

    Greenstein, Vivienne C; Duncker, Tobias; Holopigian, Karen; Carr, Ronald E; Greenberg, Jonathan P; Tsang, Stephen H; Hood, Donald C

    2012-02-01

    To analyze the structure and visual function of regions bordering the hyperautofluorescent ring/arcs in retinitis pigmentosa. Twenty-one retinitis pigmentosa patients (21 eyes) with rings/arcs and 21 normal individuals (21 eyes) were studied. Visual sensitivity in the central 10° was measured with microperimetry. Retinal structure was evaluated with spectral-domain optical coherence tomography. The distance from the fovea to disruption/loss of the inner outer segment (IS/OS) junction and thicknesses of the total receptor plus retinal pigment epithelial complex and outer segment plus retinal pigment epithelial complex layers were measured. Results were compared with measurements of the distance from the fovea to the inner and outer borders of the ring/arc seen on fundus autofluorescence. Disruption/loss of the inner outer segment junction occurred closer to the inner border of the ring/arc and it was closer to the fovea in eight eyes. For 19 eyes, outer segment plus and receptor plus RPE complex thicknesses were significantly decreased at locations closer to the fovea than the appearance of the inner border of hyperautofluorescence. Mean visual sensitivity was decreased inside, across, and outside the ring/arc by 3.5 ± 3.8, 8.9 ± 4.8, and 17.0 ± 2.4 dB, respectively. Structural and functional changes can occur inside the hyperfluorescent ring/arc in retinitis pigmentosa.

  18. Fundus Autofluorescence and Optical Coherence Tomography Findings in Branch Retinal Vein Occlusion

    Directory of Open Access Journals (Sweden)

    Tetsuju Sekiryu

    2012-01-01

    Full Text Available Purpose. To describe the findings of fundus autofluorescence (FAF and optical coherence tomography (OCT in patients with branch retinal vein occlusion (BRVO. Methods. In this institutional, retrospective, observational case series, FAF was evaluated in 65 eyes with BRVO in 64 consecutive patients and compared with visual acuity, OCT findings, and other clinical observations. Results. Five types of autofluorescence appeared during the course of BRVO: (1 petaloid-shaped hyperautofluorescence in the area of macular edema and (2 hyperautofluorescence coincident with yellow subretinal deposits. (3 Diffuse hyperautofluorescence appeared within the area of serous retinal detachment (SRD and OCT showed precipitates on the undersurface of the retina in 5/5 of these eyes (100%. (4 The area of vein occlusion showed diffuse hyperautofluorescence after resolution of the retinal bleeding. (5 Hard exudates exhibited hyper- or hypoautofluorescence. OCT indicated that most of the hard exudates with hyperautofluorescence were located on the retinal pigment epithelium. Conclusions. Hyperautofluorescence associated with subretinal fluid or hard exudate appeared in the subretinal space. This type of hyperautofluorescence may be attributed to blood cell or macrophages. FAF and OCT are noninvasive modalities that provide additional information regarding macular edema due to BRVO.

  19. Optical coherence tomography and fundus autofluorescence findings in presumed congenital simple retinal pigment epithelium hamartoma

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    Baskaran, Prabu

    2017-10-01

    Full Text Available Aim: Presumed congenital simple retinal pigment epithelium hamartoma is a rare benign lesion of the macula that mimics congenital hypertrophy of the retinal pigment epithelium (RPE and combined hamartoma of the retina and the RPE; newer imaging modalities can help in diagnosis. We report three patients with presumed congenital simple RPE hamartoma, and describe the enhanced-depth imaging optical coherence tomography (EDI-OCT and fundus autofluorescence (FAF findings. Methods: Two patients were asymptomatic; one had an intraocular foreign body in addition to the hamartoma. All had a similar jet black, elevated lesion in the macula, sparing the fovea. EDI-OCT showed a characteristic hyperreflective layer with complete optical shadowing of the deeper layers; FAF showed pronounced hypoautofluorescence of the lesion. Conclusion: Multimodal imaging with FAF and EDI-OCT can help to differentiate simple RPE hamartoma from similar RPE lesions, and may serve as a useful adjunct to clinical diagnosis of this rare tumor. We present the second largest series of presumed congenital simple RPE hamartoma, and – to the best of our knowledge – the first report of FAF findings of this tumor.

  20. Fundus auto fluorescence and spectral domain ocular coherence tomography in the early detection of chloroquine retinopathy

    Directory of Open Access Journals (Sweden)

    Megan B. Goodman

    2015-08-01

    Full Text Available Purpose: To determine the sensitivity of spectral domain ocular coherence tomography (SD-OCT and fundus auto fluorescence (FAF images as a screening test to detect early changes in the retina prior to the onset of chloroquine retinopathy. Method: The study was conducted using patients taking chloroquine (CQ, referred by the Rheumatology Department to the Ophthalmology Department at Tygerberg Academic Hospital. Group A consisted of 59 patients on CQ for less than 5 years, and Group B consisted of 53 patients on CQ for more than 5 years. A 200 × 200 macula thickness map, 5-line raster SD-OCT on a Carl Zeiss Meditec Cirrus HD-OCT and FAF images on a Carl Zeiss Meditec Visucam 500 were recorded for 223 eyes. Images were reviewed independently, and then those of Groups A and B compared. Results: There were no statistically significant differences between Groups A and B. The criteria included the internal limiting membrane and the retinal pigment epithelium (ILM-RPE thickness, interdigitation zone integrity (p = 0.891, df = 1, χ² = 0.1876, ellipsoid zone integrity (p = 0.095, df = 2, χ² = 4.699 and FAF image irregularities (p = 0.479, df = 1, χ²= 4995978. Conclusion: The inclusion of SD-OCT and FAF as objective tests into the prescribed screening guidelines does not appear to simplify the detection of subclinical injury in patients on chloroquine treatment.

  1. Automated segmentation of geographic atrophy in fundus autofluorescence images using supervised pixel classification.

    Science.gov (United States)

    Hu, Zhihong; Medioni, Gerard G; Hernandez, Matthias; Sadda, Srinivas R

    2015-01-01

    Geographic atrophy (GA) is a manifestation of the advanced or late stage of age-related macular degeneration (AMD). AMD is the leading cause of blindness in people over the age of 65 in the western world. The purpose of this study is to develop a fully automated supervised pixel classification approach for segmenting GA, including uni- and multifocal patches in fundus autofluorescene (FAF) images. The image features include region-wise intensity measures, gray-level co-occurrence matrix measures, and Gaussian filter banks. A [Formula: see text]-nearest-neighbor pixel classifier is applied to obtain a GA probability map, representing the likelihood that the image pixel belongs to GA. Sixteen randomly chosen FAF images were obtained from 16 subjects with GA. The algorithm-defined GA regions are compared with manual delineation performed by a certified image reading center grader. Eight-fold cross-validation is applied to evaluate the algorithm performance. The mean overlap ratio (OR), area correlation (Pearson's [Formula: see text]), accuracy (ACC), true positive rate (TPR), specificity (SPC), positive predictive value (PPV), and false discovery rate (FDR) between the algorithm- and manually defined GA regions are [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text], respectively.

  2. Exudate-based diabetic macular edema detection in fundus images using publicly available datasets

    Energy Technology Data Exchange (ETDEWEB)

    Giancardo, Luca [ORNL; Meriaudeau, Fabrice [ORNL; Karnowski, Thomas Paul [ORNL; Li, Yaquin [University of Tennessee, Knoxville (UTK); Garg, Seema [University of North Carolina; Tobin Jr, Kenneth William [ORNL; Chaum, Edward [University of Tennessee, Knoxville (UTK)

    2011-01-01

    Diabetic macular edema (DME) is a common vision threatening complication of diabetic retinopathy. In a large scale screening environment DME can be assessed by detecting exudates (a type of bright lesions) in fundus images. In this work, we introduce a new methodology for diagnosis of DME using a novel set of features based on colour, wavelet decomposition and automatic lesion segmentation. These features are employed to train a classifier able to automatically diagnose DME through the presence of exudation. We present a new publicly available dataset with ground-truth data containing 169 patients from various ethnic groups and levels of DME. This and other two publicly available datasets are employed to evaluate our algorithm. We are able to achieve diagnosis performance comparable to retina experts on the MESSIDOR (an independently labelled dataset with 1200 images) with cross-dataset testing (e.g., the classifier was trained on an independent dataset and tested on MESSIDOR). Our algorithm obtained an AUC between 0.88 and 0.94 depending on the dataset/features used. Additionally, it does not need ground truth at lesion level to reject false positives and is computationally efficient, as it generates a diagnosis on an average of 4.4 s (9.3 s, considering the optic nerve localization) per image on an 2.6 GHz platform with an unoptimized Matlab implementation.

  3. Automatic Diabetic Macular Edema Detection in Fundus Images Using Publicly Available Datasets

    Energy Technology Data Exchange (ETDEWEB)

    Giancardo, Luca [ORNL; Meriaudeau, Fabrice [ORNL; Karnowski, Thomas Paul [ORNL; Li, Yaquin [University of Tennessee, Knoxville (UTK); Garg, Seema [University of North Carolina; Tobin Jr, Kenneth William [ORNL; Chaum, Edward [University of Tennessee, Knoxville (UTK)

    2011-01-01

    Diabetic macular edema (DME) is a common vision threatening complication of diabetic retinopathy. In a large scale screening environment DME can be assessed by detecting exudates (a type of bright lesions) in fundus images. In this work, we introduce a new methodology for diagnosis of DME using a novel set of features based on colour, wavelet decomposition and automatic lesion segmentation. These features are employed to train a classifier able to automatically diagnose DME. We present a new publicly available dataset with ground-truth data containing 169 patients from various ethnic groups and levels of DME. This and other two publicly available datasets are employed to evaluate our algorithm. We are able to achieve diagnosis performance comparable to retina experts on the MESSIDOR (an independently labelled dataset with 1200 images) with cross-dataset testing. Our algorithm is robust to segmentation uncertainties, does not need ground truth at lesion level, and is very fast, generating a diagnosis on an average of 4.4 seconds per image on an 2.6 GHz platform with an unoptimised Matlab implementation.

  4. Microaneurysms detection with the radon cliff operator in retinal fundus images

    Energy Technology Data Exchange (ETDEWEB)

    Giancardo, Luca [ORNL; Meriaudeau, Fabrice [ORNL; Karnowski, Thomas Paul [ORNL; Tobin Jr, Kenneth William [ORNL; Li, Yaquin [University of Tennessee, Knoxville (UTK); Chaum, Edward [University of Tennessee, Knoxville (UTK)

    2010-01-01

    Diabetic Retinopathy (DR) is one of the leading causes of blindness in the industrialized world. Early detection is the key in providing effective treatment. However, the current number of trained eye care specialists is inadequate to screen the increasing number of diabetic patients. In recent years, automated and semi-automated systems to detect DR with color fundus images have been developed with encouraging, but not fully satisfactory results. In this study we present the initial results of a new technique for the detection and localization of microaneurysms, an early sign of DR. The algorithm is based on three steps: candidates selection, the actual microaneurysms detection and a final probability evaluation. We introduce the new Radon Cliff operator which is our main contribution to the field. Making use of the Radon transform, the operator is able to detect single noisy Gaussian-like circular structures regardless of their size or strength. The advantages over existing microaneurysms detectors are manifold: the size of the lesions can be unknown, it automatically distinguishes lesions from the vasculature and it provides a fair approach to microaneurysm localization even without post-processing the candidates with machine learning techniques, facilitating the training phase. The algorithm is evaluated on a publicly available dataset from the Retinopathy Online Challenge.

  5. Optical design considerations when imaging the fundus with an adaptive optics correction

    Science.gov (United States)

    Wang, Weiwei; Campbell, Melanie C. W.; Kisilak, Marsha L.; Boyd, Shelley R.

    2008-06-01

    Adaptive Optics (AO) technology has been used in confocal scanning laser ophthalmoscopes (CSLO) which are analogous to confocal scanning laser microscopes (CSLM) with advantages of real-time imaging, increased image contrast, a resistance to image degradation by scattered light, and improved optical sectioning. With AO, the instrumenteye system can have low enough aberrations for the optical quality to be limited primarily by diffraction. Diffraction-limited, high resolution imaging would be beneficial in the understanding and early detection of eye diseases such as diabetic retinopathy. However, to maintain diffraction-limited imaging, sufficient pixel sampling over the field of view is required, resulting in the need for increased data acquisition rates for larger fields. Imaging over smaller fields may be a disadvantage with clinical subjects because of fixation instability and the need to examine larger areas of the retina. Reduction in field size also reduces the amount of light sampled per pixel, increasing photon noise. For these reasons, we considered an instrument design with a larger field of view. When choosing scanners to be used in an AOCSLO, the ideal frame rate should be above the flicker fusion rate for the human observer and would also allow user control of targets projected onto the retina. In our AOCSLO design, we have studied the tradeoffs between field size, frame rate and factors affecting resolution. We will outline optical approaches to overcome some of these tradeoffs and still allow detection of the earliest changes in the fundus in diabetic retinopathy.

  6. Automatic detection of the macula in retinal fundus images using seeded mode tracking approach.

    Science.gov (United States)

    Wong, Damon W K; Liu, Jiang; Tan, Ngan-Meng; Yin, Fengshou; Cheng, Xiangang; Cheng, Ching-Yu; Cheung, Gemmy C M; Wong, Tien Yin

    2012-01-01

    The macula is the part of the eye responsible for central high acuity vision. Detection of the macula is an important task in retinal image processing as a landmark for subsequent disease assessment, such as for age-related macula degeneration. In this paper, we have presented an approach to automatically determine the macula centre in retinal fundus images. First contextual information on the image is combined with a statistical model to obtain an approximate macula region of interest localization. Subsequently, we propose the use of a seeded mode tracking technique to locate the macula centre. The proposed approach is tested on a large dataset composed of 482 normal images and 162 glaucoma images from the ORIGA database and an additional 96 AMD images. The results show a ROI detection of 97.5%, and 90.5% correct detection of the macula within 1/3DD from a manual reference, which outperforms other current methods. The results are promising for the use of the proposed approach to locate the macula for the detection of macula diseases from retinal images.

  7. Microaneurysms detection with the radon cliff operator in retinal fundus images

    Science.gov (United States)

    Giancardo, Luca; Mériaudeau, Fabrice; Karnowski, Thomas P.; Tobin, Kenneth W.; Li, Yaqin; Chaum, Edward

    2010-03-01

    Diabetic Retinopathy (DR) is one of the leading causes of blindness in the industrialized world. Early detection is the key in providing effective treatment. However, the current number of trained eye care specialists is inadequate to screen the increasing number of diabetic patients. In recent years, automated and semi-automated systems to detect DR with color fundus images have been developed with encouraging, but not fully satisfactory results. In this study we present the initial results of a new technique for the detection and localization of microaneurysms, an early sign of DR. The algorithm is based on three steps: candidates selection, the actual microaneurysms detection and a final probability evaluation. We introduce the new Radon Cliff operator which is our main contribution to the field. Making use of the Radon transform, the operator is able to detect single noisy Gaussian-like circular structures regardless of their size or strength. The advantages over existing microaneurysms detectors are manifold: the size of the lesions can be unknown, it automatically distinguishes lesions from the vasculature and it provides a fair approach to microaneurysm localization even without post-processing the candidates with machine learning techniques, facilitating the training phase. The algorithm is evaluated on a publicly available dataset from the Retinopathy Online Challenge.

  8. Decision support system for the detection and grading of hard exudates from color fundus photographs

    Science.gov (United States)

    Jaafar, Hussain F.; Nandi, Asoke K.; Al-Nuaimy, Waleed

    2011-11-01

    Diabetic retinopathy is a major cause of blindness, and its earliest signs include damage to the blood vessels and the formation of lesions in the retina. Automated detection and grading of hard exudates from the color fundus image is a critical step in the automated screening system for diabetic retinopathy. We propose novel methods for the detection and grading of hard exudates and the main retinal structures. For exudate detection, a novel approach based on coarse-to-fine strategy and a new image-splitting method are proposed with overall sensitivity of 93.2% and positive predictive value of 83.7% at the pixel level. The average sensitivity of the blood vessel detection is 85%, and the success rate of fovea localization is 100%. For exudate grading, a polar fovea coordinate system is adopted in accordance with medical criteria. Because of its competitive performance and ability to deal efficiently with images of variable quality, the proposed technique offers promising and efficient performance as part of an automated screening system for diabetic retinopathy.

  9. Factores perinatales asociados al desarrollo de alergia a las proteínas de la leche de vaca

    Directory of Open Access Journals (Sweden)

    E.M. Toro Monjaraz

    2015-01-01

    Conclusión: Los factores asociados estadísticamente significativos fueron la duración de la lactancia materna y el uso de antibióticos durante la etapa gestacional, lo que obliga a realizar estudios prospectivos.

  10. Las cooperativas de trabajo asociado en Colombia: balance de la política gubernamental 2002-2007

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    Stephano Farné

    2008-06-01

    Full Text Available En los ��ltimos años ha habido un gran crecimiento del sector cooperativo asociado en Colombia. Muchas empresas públicas y privadas contratan mediante Cooperativas de Trabajo Asociado (CTA debido a las economías provenientes de la tercerización y a los beneficios y exenciones de que gozan las CTA. Estas ventajas del cooperativismo asociado han llevado a la proliferación de pseudo CTA, que reemplazan la solidaridad y la autogestión por la búsqueda de menores costos laborales y mayores ganancias para sus falsos “propietarios” y las empresas-clientes, a costa de los derechos y del bienestar de los asociados. Hasta ahora, la actitud del Gobierno ha sido ambigua. Por un lado, ha ejercido controles laxos, y estimulado su creación, especialmente en el sector de la salud y en empresas públicas reestructuradas. Por otro lado, ha intentado reducir los incentivos económicos existentes en la legislación laboral, con poco éxito. Debido a esta ambigüedad se carece de una reglamentación seria que dé un tratamiento realista y técnico a la problemática del sector, y que haga la distinción necesaria entre CTA y pseudo CTA.

  11. Prevalencia y factores asociados a macrosomía en Perú, 2013

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    Antonio José Ledo Alves da Cunha

    Full Text Available Objetivos. Determinar la prevalencia de macrosomía y factores asociados en Perú, y describir la ocurrencia de complicaciones durante el parto y posparto. Materiales y métodos. Los pesos al nacer de los niños menores de cinco años fueron analizados usando datos de la Encuesta Demográfica y de Salud Familiar (ENDES 2013, llevada a cabo por el Instituto Nacional de Estadística e Informática. Los niños con un peso mayor a 4000 g al nacer fueron considerados como macrosómicos. Se empleó un análisis de regresión logística para establecer la asociación independiente de factores sociodemográficos con la macrosomía. Resultados. La muestra estuvo constituida por 6121 niños. La prevalencia de macrosomía fue 5,3% (intervalo de confianza al 95%: 4,8 a 5,9. El sexo masculino, un orden de nacimiento mayor, la obesidad materna y una mayor estatura materna estuvieron independientemente asociados con la macrosomía. Los partos por cesárea fueron más frecuentes en niños macrosómicos (43,9% vs 26,9%. Las complicaciones durante el parto y posparto fueron frecuentes, pero no estadísticamente asociadas con la macrosomía. Conclusiones. La prevalencia de macrosomía en Perú es relativamente baja comparada con otros países de ingresos bajos o medios. Los factores asociados con la macrosomía fueron principalmente no modificables, con excepción de la obesidad materna. Los niños macrosómicos nacieron más frecuentemente por cesárea. La reducción del peso y la prevención de la obesidad en mujeres en edad fértil en Perú podrían potencialmente reducir la macrosomía y las tasas de cesáreas.

  12. Clinical research on intravitreal injection of bevacizumab in the treatment of macula lutea and retinal edema of ocular fundus disease.

    Science.gov (United States)

    Yan, Ying; Wang, Tao; Cao, Jing; Wang, Meng; Li, Fenghua

    2015-07-01

    This paper aimed to explore clinically curative effect of intravitreal injection of bevacizumab in the treatment of macula lutea and retinal edema of ocular fundus disease. The number of 300 patients (390 eyes) with ocular fundus diseases including retinal vein occlusion (RVO), diabetic retinopathy (DR), age-related macular degeneration (ARMD), central serous chorioretinopathy (CSC), choridal new vessel (CNV) received and cured in the hospital from February 2010 to February 2014 were given intravitreal injection of bevacizumab (1.5mg) with once per month and a total of 2-3 times. Results of patients' vision and fluorescence fundus angiography (FFA), optical coherence tomography (OCT) before and after treatment were compared and curative effects were evaluated. Vision of 349 eyes (89.49%) improved obviously with the average of more than 2 lines, patient's intraocular pressure (IOP) was normal and all indexes were clearly better; vision of 26 eyes (6.67%) was stable before the treatment and without any changes after the treatment, the situation of fundus got better without increased IOP; vision of 15 eyes (3.85%) decreased to some extent, and the symptoms eased slightly after symptomatic treatment. In the 1st day after intravitreal injection, best-corrected visual acuity increased to 0.239±0.175, best-corrected visual acuity in 1 m was 0.315±0.182, in 3m continuously climbed to 0.350±0.270, and in 6 m was 0.362±0.282. Compared with vision before injection, t value was t=3.184, t=7.213, t=9.274 and t=9.970 (P=0.002, P=0.000, P=0.000 and P=0.000) respectively, and all P were less than 0.01. Furthermore, the difference was significant if a=0.01, which could confirm that 1m best corrected visual acuity of patients after intravitreal injection improved clearly in combination with before injection and 3m and 6 m visions enhanced constantly after injection. To sum up, intravitreal injection of bevacizumab in treating ocular fundus disease improves patient's vision

  13. Comparison of optic area measurement using fundus photography and optical coherence tomography between optic nerve head drusen and control subjects.

    Science.gov (United States)

    Flores-Rodríguez, Patricia; Gili, Pablo; Martín-Ríos, María Dolores; Grifol-Clar, Eulalia

    2013-03-01

    To compare optic disc area measurement between optic nerve head drusen (ONHD) and control subjects using fundus photography, time-domain optical coherence tomography (TD-OCT) and spectral-domain optical coherence tomography (SD-OCT). We also made a comparison between each of the three techniques. We performed our study on 66 eyes (66 patients) with ONHD and 70 healthy control subjects (70 controls) with colour ocular fundus photography at 20º (Zeiss FF 450 IR plus), TD-OCT (Stratus OCT) with the Fast Optic Disc protocol and SD-OCT (Cirrus OCT) with the Optic Disc Cube 200 × 200 protocol for measurement of the optic disc area. The measurements were made by two observers and in each measurement a correction of the image magnification factor was performed. Measurement comparison using the Student's t-test/Mann-Whitney U test, the intraclass correlation coefficient, Pearson/Spearman rank correlation coefficient and the Bland-Altman plot was performed in the statistical analysis. Mean and standard deviation (SD) of the optic disc area in ONHD and in controls was 2.38 (0.54) mm(2) and 2.54 (0.42) mm(2), respectively with fundus photography; 2.01 (0.56) mm(2) and 1.66 (0.37) mm(2), respectively with TD-OCT, and 2.03 (0.49) mm(2) and 1.75 (0.38) mm(2), respectively with SD-OCT. In ONHD and controls, repeatability of optic disc area measurement was excellent with fundus photography and optical coherence tomography (TD-OCT and SD-OCT), but with a low degree of agreement between both techniques. Optic disc area measurement is smaller in ONHD compared to healthy subjects with fundus photography, unlike time-domain and spectral-domain optical coherence tomography in which the reverse is true. Both techniques offer good repeatability, but a low degree of correlation and agreement, which means that optic disc area measurement is not interchangeable or comparable between techniques. Ophthalmic & Physiological Optics © 2013 The College of Optometrists.

  14. Comportamientos de riesgo para la salud en adolescentes estudiantes: prevalencia y factores asociados

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    Adalberto Campo-Arias

    2008-01-01

    Resultados: La edad promedio del grupo fue 14,8 años (DE=1,6, 51,3 % varones y escolaridad promedio de 8,5 años (DE=1,6. El 21,2 % (IC95 % 17,6-24,8 presentaba un PCRS. Se observó que los síntomas depresivos con importancia clínica (OR=2,74; IC95 % 1,46-5,16, ser varón (OR=2,35; IC95 % 1,47-3,78 y baja religiosidad (OR=1,93; IC95 % 1,24-3,02 se asociaban significativamente al PCRS. Conclusiones: EL PCRS se presenta en uno de cada cinco estudiantes de esta institución y está asociado a síntomas depresivos con importancia clínica, sexo masculino y baja religiosidad.

  15. Factores asociados a la adherencia al tratamiento de Malaria en Piura y Tumbes-Perú

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    Fernando Llanos-Zavalaga

    2001-07-01

    Full Text Available La Organización Mundial de Salud considera al tratamiento temprano y adecuado como parte fundamental del programa mundial de control de la malaria. Un problema asociado a esta estrategia es la resistencia, especialmente de P. falciparum a las drogas antimaláricas. Objetivo: Determinar los factores sociales, culturales y de los servicios de salud asociados a la adherencia al tratamiento de malaria desde la perspectiva del usuario y del prestador, en poblados de los departamentos de Piura y Tumbes, Perú. Materiales y métodos: Se realizó un estudio transversal cualitativo en comunidades de los departamentos de Piura y Tumbes durante Febrero, y Marzo del 2000, para ello se aplicaron grupos focales y entrevistas en profundidad, bajo el principio de saturación. Estos fueron grabados, transcritos, revisados y codificados considerando los temas de interés, utilizando el software Atlas-ti. Resultados y conclusiones: Existen factores que influencian positiva o negativamente en la adherencia al tratamiento antimalárico. Dentro de las primeras, se identificó la conciencia de enfermedad, la confianza en la efectividad de los medicamentos, el conocimiento del riesgo de presentar complicaciones, medicamentos de fácil y corta administración, tratamiento gratuito y supervisado, y la participación de promotores de salud. Por otro lado, la rápida recuperación de síntomas, aparición de efectos adversos, presencia de población migrante y predominancia de actividad agrícola, la pobre accesibilidad, la mala calidad de atención y la automedicación influencian negativamente en la adherencia al tratamiento.

  16. Artrópodos asociados a Jatropha curcas Linnaeus. Funciones y estrategia para su manejo

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    O Alonso

    Full Text Available En la actualidad, Jatropha curcas Linnaeus constituye una de las plantas más investigadas a nivel mundial debido a su potencial como productora de aceite, el cual se puede transformar en biodiesel. Sin embargo, aún no se dispone de suficiente información sobre sus interacciones ecológicas con otros vegetales y animales; por lo que el conocimiento referente a los artrópodos asociados al piñón nombre común por el que se le conoce» es un requisito indispensable para el manejo adecuado del cultivo. El objetivo de este artículo es exponer los resultados de una recopilación realizada acerca de dichos organismos (insectos, ácaros y arañas, fundamentalmente, para lograr una mejor explotación de las plantaciones de este cultivo energético en Cuba. Dentro del grupo de los fitófagos se encontraron 151 especies de insectos, entre las que sobresalen las del orden Hemiptera, por ejemplo: Pachycoris klugii Burmeister (Scutelleridae y Leptoglossus zonatus (Dallas; además de cuatro de ácaros. Entre los benéficos se hallaron 90 especies de insectos, cinco de ácaros y 13 de arañas depredadoras. En cuanto a las estrategias de manejo de plagas, se hace un mayor énfasis en las medidas de control químico y en algunas acciones de tipo cultural. Teniendo en cuenta estos antecedentes, en Cuba es imprescindible conocer los principales organismos asociados a dicha planta, con vistas a incorporar con mayor precisión el componente agroecológico en el manejo de las plagas, y con ello contribuir al mantenimiento de las capacidades productivas de los agroecosistemas y a su resiliencia.

  17. Factores asociados a mortalidad perinatal en el hospital general de Chiapas, México

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    Rivera Leonor

    2003-01-01

    Full Text Available OBJETIVO: El objetivo del estudio es identificar factores socioeconómicos, gineco-obstétricos y del producto asociados a mortalidad perinatal. MÉTODOS: Se realizó un estudio de casos y controles pareado. Se consideró caso a los nacidos vivos o muertos que nacieron y fallecieron entre las 28 semanas de gestación a los 7 días de vida extrauterina. y control al producto nacido vivo entre las 28 semanas de gestación y los 7 días de vida extrauterina. Los datos se obtuvieron de los expedientes clínicos hospitalarios. Se estudiaron 99 casos y 197 controles. Se hizo un análisis estadístico utilizando Stata 6.0. RESULTADOS La media de edad de la madre fue de 24.82 años y del producto de 37.78 semanas de gestación. El promedio de peso del producto fue de 2,760 gramos. Los factores asociados a mortalidad perinatal fueron: ocupación del padre agricultor (RM ajustada 3,31; IC 95% 1,26-8,66; índice de riesgo obstétrico alto (RM ajustada 10,57; IC 95% 2,82-39,66, antecedente de cesárea (RM ajustada 2,75; IC 95% 1,37-5,51; cinco y más consultas prenatales (RM ajustada 4,43; IC 95% 1.86-10,54; producto pretérmino (RM ajustada 9,20; IC 95% 4,39-19,25. CONCLUSIONES: Los resultados muestran que es necesario implementar medidas de prevención y control que aseguren la identificación del riesgo en las mujeres embarazadas, con el fin de abatir la incidencia de mortalidad perinatal.

  18. Factores asociados a mortalidad perinatal en el hospital general de Chiapas, México

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    Leonor Rivera

    2003-12-01

    Full Text Available OBJETIVO: El objetivo del estudio es identificar factores socioeconómicos, gineco-obstétricos y del producto asociados a mortalidad perinatal. MÉTODOS: Se realizó un estudio de casos y controles pareado. Se consideró caso a los nacidos vivos o muertos que nacieron y fallecieron entre las 28 semanas de gestación a los 7 días de vida extrauterina. y control al producto nacido vivo entre las 28 semanas de gestación y los 7 días de vida extrauterina. Los datos se obtuvieron de los expedientes clínicos hospitalarios. Se estudiaron 99 casos y 197 controles. Se hizo un análisis estadístico utilizando Stata 6.0. RESULTADOS La media de edad de la madre fue de 24.82 años y del producto de 37.78 semanas de gestación. El promedio de peso del producto fue de 2,760 gramos. Los factores asociados a mortalidad perinatal fueron: ocupación del padre agricultor (RM ajustada 3,31; IC 95% 1,26-8,66; índice de riesgo obstétrico alto (RM ajustada 10,57; IC 95% 2,82-39,66, antecedente de cesárea (RM ajustada 2,75; IC 95% 1,37-5,51; cinco y más consultas prenatales (RM ajustada 4,43; IC 95% 1.86-10,54; producto pretérmino (RM ajustada 9,20; IC 95% 4,39-19,25. CONCLUSIONES: Los resultados muestran que es necesario implementar medidas de prevención y control que aseguren la identificación del riesgo en las mujeres embarazadas, con el fin de abatir la incidencia de mortalidad perinatal.

  19. BIOMASA Y RENDIMIENTO DE FRIJOL CON POTENCIAL EJOTERO EN UNICULTIVO Y ASOCIADO CON GIRASOL

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    J. Garduño-González

    2009-01-01

    Full Text Available El objetivo del presente estudio fue estimar la producción de biomasa, rendimiento y algunos de sus componentes de dos cultivares de frijol (Phaseolus vulgaris L. con potencial ejotero ('Acerado' y 'Criollo', en unicultivo y asociado con dos cultivares de girasol (Helianthus annuus L. ('Sunbright' y 'Victoria'. El estudio se realizó durante el ciclo primavera verano 2006 bajo condiciones de temporal en Tenancingo, Méx. Las variables evaluadas fueron: índice de área foliar (IAF, tasa de asimilación neta (TAN, biomasa total (BT, diámetro de vaina (DV, longitud de vaina (LV, número de vainas·m-2 (NV y rendimiento de vaina·m-2 (RV; las cuales fueron analizadas en arreglo factorial, bajo un diseño de bloques completos al azar con cuatro repeticiones. Para estimar el grado de asociación, entre las variables estudiadas y el rendimiento de vainas, se realizó un análisis de correlación lineal simple. En el factor cultivares se detectaron diferencias estadísticas significativas para la TAN y DV; para el factor sistemas de siembra hubo diferencias significativas para BT, DV, NV y RV. La interacción cultivares * sistema de siembra fue significativa en todas las variables, excepto en la TAN. En ese sentido, las asociaciones 'Criollo' + 'Sunbright', 'Acerado' + 'Victoria' y 'Acerado' en unicultivo, presentaron el mayor RV. Las variables IAF, BT y NV se correlacionaron positiva y significativamente con el rendimiento de vaina. Los resultados indican que 'Criollo' y 'Acerado', asociados con 'Sunbright' y 'Victoria', respectivamente, responden positivamente a la asociación, constituyendo una buena opción para los productores de la región de Tenancingo, México.

  20. Loci asociados con enfermedades genéticas y calidad de carne en bovinos Charolais Mexicanos

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    Ana María Sifuentes Rincón

    2015-01-01

    Full Text Available Se determinaron las frecuencias alélicas y genotípicas de ocho marcadores localizados en los genes calpaína (CAPN, 4 751 y 316, calpastatina (CASTT1 y tiroglobulina (TG5, asociados a calidad de carne, y en los genes, m iost atina (MSTN, Q204X, arginino succinato sintasa (ASS, monofosfato sintasa (UMPS y miofosforilasa (PYGM, asocia dos a enfermedade s genéticas de ganado bovino. Se muestrearon 493 animales Charolais de registro de dos hatos ubicado s en Sonora (n=157 y tres en Nuevo León (n=336. No se encontraron portadores de los alelos T-ASS y T-UM PS, pero sí portadores del alelo Q204X del gen MSTN en frecuencias de  1 % en las poblaciones de Sonora y de 8.6 a 14.4 % en las de Nuevo León. Además, se identificaron portadores del marcador del gen PYGM, en frecuencias del 6.5 y de 1.0 % para un hato de Sonora y otro de Nuevo León, respectivamente. El análisis de diferenciación génica p areado entre las poblaciones y con los cuatro loci mostró que hay diferencias altamente significativas dentro de pobl aciones del noroeste ( P <0.0001 y entre éstas y las del noreste ( P <0.001, la cual es explicada principalmente por los loci CAPN-316 y TG5. De acuerdo a los resultados obtenidos se recomienda el monitoreo del marcador del gen PYGM y del ale lo Q204X del gen MSTN, así como también implementar estrategias para confirmar la utilidad de los marcadores asociado s a calidad y productividad como herramienta para complementar los progra mas de mejoramiento genético.

  1. Factores socio-culturales asociados a la actividad sexual de los adolescentes

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    William Atehortua-Puerta

    2014-06-01

    Full Text Available Objetivo: identificar los factores socioculturales asociados a la actividad sexual de los adolescentes. Materiales y Métodos: estudio cuantitativo-descriptivo, con muestreo probabilístico de tipo aleatorio simple, en una población de adolescentes escolarizados entre 13 y 19 años de los sectores público y privado. Para la realización de este estudio los investigadores realizaron una adaptación y modificación de un instrumento usado en un estudio similar, previa notificación y autorización de uso a la autora. Resultados: en los factores sociales asociados a la actividad sexual de los adolescentes, sobresalen el alto porcentaje de conocimiento sobre sexualidad y planificación familiar en los dos sectores, con un bajo uso en los métodos (50%, el aumento en la comunicación con los padres y la convivencia con estos, también se encontró la escasa información brindada por la escuela sobre sexualidad y el desconocimiento de los adolescentes con relación a los servicios amigables. En cuanto a los factores culturales, se observó que la virginidad hace parte de un mito, que por el modernismo y la globalización, esta cultura no es un impedimento moral para las mujeres, considerando su vida sexual como un derecho que pueden ejercer. Conclusiones: los adolescentes de los colegios estudiados, inician relaciones sexuales antes de alcanzar la mayoría de edad, considerándose como factores causales el uso inadecuado de la información que los adolescentes adquieren de los medios masivos de comunicación, colegio y familia, y las diversas influencias culturales que ven las relaciones sexuales como una actividad natural en la adolescencia.

  2. Desarrollo de una escala para evaluar recursos de personalidad asociados a la resiliencia infantil

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    Viviana Lemos

    Full Text Available Resumen El estudio de la resiliencia, capacidad humana para sobreponerse a las adversidades, construir sobre ellas y salir fortalecido, posee una gran relevancia, dadas las implicancias que tiene en la prevención y promoción positiva del desarrollo humano. En este sentido, el objetivo de este trabajo fue evaluar de manera válida y confiable algunos de los recursos de personalidad asociados comúnmente por la literatura a la resiliencia infantil: autocontrol, empatía, prosocialidad, autoeficacia y creatividad. Se realizaron dos estudios para analizar diferentes aspectos complementarios de las propiedades psicométricas del instrumento. El primer estudio (E1 se desarrolló con una muestra intencional de 216 niños de ambos sexos, de 9 a 12 años, de tres provincias de la República Argentina. El segundo estudio (E2, con una muestra de 479 niños de características semejantes al E1. Se realizó un Análisis Factorial Exploratorio y uno Confirmatorio, se estudió el poder discriminativo de los ítems, la consistencia interna del instrumento y diferentes análisis de validez de constructo convergente y discriminante. Los resultados de ambos estudios permiten indicar que la versión final del instrumento cumple con los criterios esperados de validez y confiabilidad. La escala desarrollada permite obtener, a partir de una prueba psicológica breve y de sencilla aplicación, un perfil de recursos de personalidad asociados a la resiliencia infantil. Teniendo en cuenta que dichos recursos constituyen sólo un aspecto a considerar en la evaluación de este importante constructo, se sugiere complementar esta información con la evaluación de los riesgos y las competencias en otros ámbitos del desarrollo psicológico.

  3. MORTALIDAD YCOSTES ASOCIADOS A LA DEMORA DEL TRATAMIENTO QUIRÚRGICO POR FRACTURA DE CADERA

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    Iñigo Etxebarria-Foronda

    2013-01-01

    Full Text Available Fundamentos: La intervención quirúrgica en las fracturas de cadera suele demorarse varios días. Nuestro trabajo tiene dos objetivos. Estudiar la estancia preoperatoria de los pacientes ingresados por fractura de cade- ra en los hospitales vascos durante el año 2010 y medir su posible asocia- ción con la mortalidad intrahospitalaria, y estimar el coste económico que supone la estancia preoperatoria. Métodos. Se realizó un estudio observacional analizando los siguien- tes datos del Conjunto Mínimo Básico de Datos (CMBD: hospital, edad, sexo, estancia preoperatoria, estado al alta, diagnósticos asociados y pro- cedimiento quirúrgico. Además, se estudió el índice de comorbilidad de Charlson y se calculó el coste unitario de la estancia pre y postoperatoria mediante modelos de regresión múltiple. Resultados. Se analizó una muestra de 1.856 intervenciones. La es- tancia preoperatoria fue de 2,7 días y la postoperatoria de 9,7 días. El cos- te medio por ingreso fue de 12.552,12 euros. El coste medio de la estan- cia preoperatoria fue de 1295,5 euros. La mortalidad fue del 5%. Conclusiones. La estancia preoperatoria no es un factor estadística- mente asociado con la mortalidad, aunque aumenta significativamente el coste total. No encontramos una asociación entre la demora quirúrgica y la mortalidad, aunque sí tiene una clara influencia en el coste total del proceso. La reducción del tiempo prequirúrgico permite ahorrar costes.

  4. Diagnostic Accuracy of Nonmydriatic Fundus Photography for the Detection of Glaucoma in Diabetic Patients

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    Francisco J. Muñoz-Negrete

    2015-01-01

    Full Text Available Purpose. To determine the diagnostic accuracy for glaucoma of a set of criteria with nonmydriatic monoscopic fundus photography (NMFP in diabetics. Methods. Diabetics recruited from a screening program for diabetic retinopathy and diabetic glaucoma patients recruited from our glaucoma unit were included. Any patient with evidence of diabetic retinopathy was excluded. Diabetic patients had to have no visual field defects to be included as controls. Glaucoma patients had to have a glaucomatous field defect in at least one eye to be included. One NMFP was taken per eye for all subjects. These photographs were evaluated by two masked glaucoma specialists for the presence of the following: bilateral cup to disc (C/D ratio ≥0.6, notching or thinning of the neuroretinal rim, disc hemorrhages, and asymmetry in the C/D ratio between both eyes ≥0.2. This evaluation led to a dichotomous classification: if any of the above criteria was present, the patient was classified as glaucoma. If none were present, the patient was classified as normal. Results. 72 control subjects and 72 glaucoma patients were included. Evaluation of NMFP had a sensitivity of 79.17% and a specificity of 80.56% for specialist 1 and a sensitivity of 72.22% and a specificity of 88.88% for specialist 2 for the detection of glaucoma. The overall accuracy was 79.83% and 80.55%, respectively. Discussion. NMFP evaluation by a glaucoma specialist may be useful for the detection of glaucoma in diabetics.

  5. A longitudinal study of Stargardt disease: quantitative assessment of fundus autofluorescence, progression, and genotype correlations.

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    Fujinami, Kaoru; Lois, Noemi; Mukherjee, Rajarshi; McBain, Vikki A; Tsunoda, Kazushige; Tsubota, Kazuo; Stone, Edwin M; Fitzke, Fred W; Bunce, Catey; Moore, Anthony T; Webster, Andrew R; Michaelides, Michel

    2013-12-17

    We characterized subtypes of fundus autofluorescence (AF) and the progression of retinal atrophy, and correlated these findings with genotype in Stargardt disease. Full clinical examination and AF imaging was undertaken in 68 patients with Stargardt disease. The baseline data were compared to those at follow-up. Patients were classified into three AF subtypes: type 1 had a localized low signal at the fovea surrounded by a homogeneous background, type 2 had a localized low signal at the macula surrounded by a heterogeneous background with numerous foci of abnormal signal, and type 3 had multiple low signal areas at the posterior pole with a heterogeneous background. At baseline, there were 19 patients with type 1, 41 with type 2, and 8 with type 3 disease. The areas of reduced AF signal were measured and rate of atrophy enlargement (RAE) was calculated as the difference of the atrophy size over time (mm²) divided by the follow-up interval (years). Molecular screening of ABCA4 was undertaken. The mean follow-up interval was 9.1 years. A total of 42% cases with type 1 disease progressed to type 2, and 12% with type 2 progressed to type 3. The RAE (mm²/y) based upon baseline AF subtypes was significantly different; 0.06 in type 1, 0.67 in type 2, and 4.37 in type 3. ABCA4 variants were identified in 57 patients. There was a significant association between AF subtype and genotype. The AF pattern at baseline influences the enlargement of atrophy over time and has genetic correlates. These data are likely to assist in the provision of counseling on prognosis in Stargardt disease and be valuable for future clinical trials.

  6. Diabetic retinal pigment epitheliopathy: fundus autofluorescence and spectral-domain optical coherence tomography findings.

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    Kang, Eui Chun; Seo, Yuri; Byeon, Suk Ho

    2016-10-01

    To describe the characteristics of an unfamiliar disease entity, diabetic retinal pigment epitheliopathy (DRPE), using fundus autofluorescence (FAF) and spectral-domain optical coherence tomography (SD-OCT). This retrospective study included 17 eyes from 10 proliferative diabetic retinopathy (PDR) patients with granular hypo-autofluorescence and/or variable hyper-autofluorescence on FAF (DRPE group) and 17 eyes from 10 age- and sex-matched PDR patients without abnormal autofluorescence (PDR group). Eyes with diabetic macular edema were excluded. Visual acuity (VA), retinal thickness (RT), and choroidal thickness (CT) were compared between the groups. Eyes in the DRPE group had worse logMAR VA than eyes in the PDR group (0.369 ± 0.266 vs. 0.185 ± 0.119; P = 0.026). The thickness of the retinal pigment epithelium plus the inner segment/outer segment of the photoreceptors was reduced to a greater degree in the DRPE group than the PDR group (P retina showed no differences between the two groups. CT was significantly thicker in the DRPE group than in the PDR group (329.00 ± 33.76 vs. 225.62 ± 37.47 μm; P retina, and thicker choroid in comparison with eyes with PDR. Alterations of autofluorescence on FAF and changes in the outer retinal thickness and CT on SD-OCT can be helpful for differentiating DRPE in patients with PDR.

  7. THE EFFECT OF PHOTOPIGMENT BLEACHING ON FUNDUS AUTOFLUORESCENCE IN ACUTE CENTRAL SEROUS CHORIORETINOPATHY.

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    Choi, Kwang-Eon; Yun, Cheolmin; Kim, Young-Ho; Kim, Seong-Woo; Oh, Jaeryung; Huh, Kuhl

    2017-03-01

    To evaluate the effect of photobleaching on fundus autofluorescence (FAF) images in acute central serous chorioretinopathy. We obtained prephotobleaching and postphotobleaching images using an Optomap 200Tx, and photobleaching was induced with a Heidelberg Retina Angiograph 2. Degrees of photobleaching were assessed as grayscale values in Optomap images. Concordances among the three kinds of images were analyzed. Hyper-AF lesions in prephotobleaching images were classified as Type 1 (changed to normal-AF after photobleaching) and Type 2 (unchanged after photobleaching). The FAF composite patterns of central serous chorioretinopathy lesions were classified as diffuse or mottled. Initial and final best-corrected visual acuity, central retinal thickness, and disease duration were compared according to fovea FAF type. Forty-one eyes of 41 patients were analyzed. The lesion brightness of postphotobleaching Optomap FAF showed greater concordance with Heidelberg Retina Angiograph 2 FAF (94.74%) than the prephotobleaching Optomap FAF (80.49%). Eyes with Type 1 fovea had greater initial and final best-corrected visual acuity (20/23 vs. 20/41, 20/21 vs. 20/32, P < 0.0001, P = 0.001, respectively) and shorter disease duration (19.68 ± 12.98 vs. 51.55 ± 44.98 days, P = 0.043) than those with Type 2 fovea. However, eyes with diffuse Type 2 fovea had only lower initial and final best-corrected visual acuity (20/23 vs. 20/45, 20/21 vs. 20/36, P < 0.0001, P < 0.0001, respectively) than those with Type 1 fovea. Understanding the photobleaching effect is necessary for the accurate interpretation of FAF images. Furthermore, comparing prephotobleaching and postphotobleaching FAF images may be helpful for estimation of lesion status in central serous chorioretinopathy.

  8. Ultra-widefield fundus autofluorescence in age-related macular degeneration.

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    Abhilash Guduru

    Full Text Available Establish accuracy and reproducibility of subjective grading in ultra-widefield fundus autofluorescence (FAF imaging in patients with age-related macular degeneration (AMD, and determine if an association exists between peripheral FAF abnormalities and AMD.This was a prospective, single-blinded case-control study. Patients were consecutively recruited for the study. Patients were excluded if there was a history of prior or active ocular pathology other than AMD or image quality was insufficient for analysis as determined by two independent graders. Control patients were those without any evidence of AMD or other ophthalmic disease apart from cataract. Using the Optos 200Tx (Optos, Marlborough, MA, USA, a ResMax central macula and an ultra-widefield peripheral retina image was taken for each eye in both normal color and short wavelength FAF. Ultra-widefield photographs were modified to mask the macula. Each ResMax and ultra-widefield image was independently graded by two blinded investigators.There were 28 AMD patients and 11 controls. There was a significant difference in the average age between AMD patients and control groups (80 versus 64, respectively P<0.001. There was moderate, statistically significant agreement between observers regarding image interpretation (78.4%, K = 0.524, P<0.001, and 69.0% (K = 0.49, P<0.001 agreement between graders for FAF abnormality patterns. Patients with AMD were at greater risk for peripheral FAF abnormalities (OR: 3.43, P = 0.019 and patients with FAF abnormalities on central macular ResMax images were at greater risk of peripheral FAF findings (OR: 5.19, P = 0.017.Subjective interpretation of FAF images has moderate reproducibility and validity in assessment of peripheral FAF abnormalities. Peripheral FAF abnormalities are seen in both AMD and control patients. Those with AMD, poor visual acuity, and macular FAF abnormalities are at greater risk.

  9. Central serous chorioretinopathy fundus autofluorescence comparison with two different confocal scanning laser ophthalmoscopes.

    Science.gov (United States)

    Nam, Ki Tae; Yun, Cheol Min; Kim, Jee Taek; Yang, Kyung-Sook; Kim, Hyun Joo; Kim, Seong-Woo; Oh, Jaeryung; Huh, Kuhl

    2015-12-01

    To compare the lesion characteristics of two different types of confocal scanning laser ophthalmoscopy (cSLO) autofluorescence (AF) images in central serous chorioretinopathy (CSC). The study included 63 eyes of 61 patients; 63 pairs of fundus autofluorescence (FAF) images were compared before CSC resolution in 63 eyes, FAF images of 31 eyes were also compared after CSC resolution. The lesion characteristics (brightness and composite pattern) were compared between Heidelberg Retina Angiograph 2 (HRA2; Heidelberg Engineering, Germany) and Optomap Tx (Optomap; Optos, Scotland) FAF images. The lesion composite pattern was categorized as diffuse or granular. Diffuse AF was defined as homogenously increased or decreased AF, and granular AF was defined as dot-like, coarse changes in AF. The mean disease duration and subretinal fluid (SRF) height in the spectral domain optical coherence tomography were compared according to the FAF image characteristics. Lesion brightness before CSC resolution was hypo-AF in 48 eyes (76.2 %), hyper-AF in three (4.8 %), and mixed-AF in 12 (19.0 %) in HRA2 FAF images. In comparison, nine (14.3 %) images were hypo-AF, 44 (69.8 %) were hyper-AF, and 10 (15.9 %) were mixed-AF in Optomap FAF images (P < 0.0001). There was no significant difference in lesion composite pattern between the two FAF image wavelengths. Patients with lesions that were hyper-AF in Optomap FAF and hypo-AF in HRA2 FAF had a shorter disease duration and greater SRF height (1 month, 281 um) than those who were hyper-AF in both Optomap and HRA2 images (26 months, 153 um; P = 0.004, 0.001). The two types of FAF images of CSC showed different lesion brightness before and after CSC resolution but demonstrated similar lesion composite patterns.

  10. Segmentation of the geographic atrophy in spectral-domain optical coherence tomography and fundus autofluorescence images.

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    Hu, Zhihong; Medioni, Gerard G; Hernandez, Matthias; Hariri, Amirhossein; Wu, Xiaodong; Sadda, Srinivas R

    2013-12-30

    Geographic atrophy (GA) is the atrophic late-stage manifestation of age-related macular degeneration (AMD), which may result in severe vision loss and blindness. The purpose of this study was to develop a reliable, effective approach for GA segmentation in both spectral-domain optical coherence tomography (SD-OCT) and fundus autofluorescence (FAF) images using a level set-based approach and to compare the segmentation performance in the two modalities. To identify GA regions in SD-OCT images, three retinal surfaces were first segmented in volumetric SD-OCT images using a double-surface graph search scheme. A two-dimensional (2-D) partial OCT projection image was created from the segmented choroid layer. A level set approach was applied to segment the GA in the partial OCT projection image. In addition, the algorithm was applied to FAF images for the GA segmentation. Twenty randomly chosen macular SD-OCT (Zeiss Cirrus) volumes and 20 corresponding FAF (Heidelberg Spectralis) images were obtained from 20 subjects with GA. The algorithm-defined GA region was compared with consensus manual delineation performed by certified graders. The mean Dice similarity coefficients (DSC) between the algorithm- and manually defined GA regions were 0.87 ± 0.09 in partial OCT projection images and 0.89 ± 0.07 in registered FAF images. The area correlations between them were 0.93 (P segment GA regions in both SD-OCT and FAF images. This approach demonstrated good agreement between the algorithm- and manually defined GA regions within each single modality. The GA segmentation in FAF images performed better than in partial OCT projection images. Across the two modalities, the GA segmentation presented reasonable agreement.

  11. An ensemble deep learning based approach for red lesion detection in fundus images.

    Science.gov (United States)

    Orlando, José Ignacio; Prokofyeva, Elena; Del Fresno, Mariana; Blaschko, Matthew B

    2018-01-01

    Diabetic retinopathy (DR) is one of the leading causes of preventable blindness in the world. Its earliest sign are red lesions, a general term that groups both microaneurysms (MAs) and hemorrhages (HEs). In daily clinical practice, these lesions are manually detected by physicians using fundus photographs. However, this task is tedious and time consuming, and requires an intensive effort due to the small size of the lesions and their lack of contrast. Computer-assisted diagnosis of DR based on red lesion detection is being actively explored due to its improvement effects both in clinicians consistency and accuracy. Moreover, it provides comprehensive feedback that is easy to assess by the physicians. Several methods for detecting red lesions have been proposed in the literature, most of them based on characterizing lesion candidates using hand crafted features, and classifying them into true or false positive detections. Deep learning based approaches, by contrast, are scarce in this domain due to the high expense of annotating the lesions manually. In this paper we propose a novel method for red lesion detection based on combining both deep learned and domain knowledge. Features learned by a convolutional neural network (CNN) are augmented by incorporating hand crafted features. Such ensemble vector of descriptors is used afterwards to identify true lesion candidates using a Random Forest classifier. We empirically observed that combining both sources of information significantly improve results with respect to using each approach separately. Furthermore, our method reported the highest performance on a per-lesion basis on DIARETDB1 and e-ophtha, and for screening and need for referral on MESSIDOR compared to a second human expert. Results highlight the fact that integrating manually engineered approaches with deep learned features is relevant to improve results when the networks are trained from lesion-level annotated data. An open source implementation of our

  12. Automated microaneurysm detection method based on double ring filter in retinal fundus images

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    Mizutani, Atsushi; Muramatsu, Chisako; Hatanaka, Yuji; Suemori, Shinsuke; Hara, Takeshi; Fujita, Hiroshi

    2009-02-01

    The presence of microaneurysms in the eye is one of the early signs of diabetic retinopathy, which is one of the leading causes of vision loss. We have been investigating a computerized method for the detection of microaneurysms on retinal fundus images, which were obtained from the Retinopathy Online Challenge (ROC) database. The ROC provides 50 training cases, in which "gold standard" locations of microaneurysms are provided, and 50 test cases without the gold standard locations. In this study, the computerized scheme was developed by using the training cases. Although the results for the test cases are also included, this paper mainly discusses the results for the training cases because the "gold standard" for the test cases is not known. After image preprocessing, candidate regions for microaneurysms were detected using a double-ring filter. Any potential false positives located in the regions corresponding to blood vessels were removed by automatic extraction of blood vessels from the images. Twelve image features were determined, and the candidate lesions were classified into microaneurysms or false positives using the rule-based method and an artificial neural network. The true positive fraction of the proposed method was 0.45 at 27 false positives per image. Forty-two percent of microaneurysms in the 50 training cases were considered invisible by the consensus of two co-investigators. When the method was evaluated for visible microaneurysms, the sensitivity for detecting microaneurysms was 65% at 27 false positives per image. Our computerized detection scheme could be improved for helping ophthalmologists in the early diagnosis of diabetic retinopathy.

  13. Automatic Detection of Microaneurysms in Color Fundus Images using a Local Radon Transform Method

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    Hamid Reza Pourreza

    2009-03-01

    Full Text Available Introduction: Diabetic retinopathy (DR is one of the most serious and most frequent eye diseases in the world and the most common cause of blindness in adults between 20 and 60 years of age. Following 15 years of diabetes, about 2% of the diabetic patients are blind and 10% suffer from vision impairment due to DR complications. This paper addresses the automatic detection of microaneurysms (MA in color fundus images, which plays a key role in computer-assisted early diagnosis of diabetic retinopathy. Materials and Methods: The algorithm can be divided into three main steps. The purpose of the first step or pre-processing is background normalization and contrast enhancement of the images. The second step aims to detect candidates, i.e., all patterns possibly corresponding to MA, which is achieved using a local radon transform, Then, features are extracted, which are used in the last step to automatically classify the candidates into real MA or other objects using the SVM method. A database of 100 annotated images was used to test the algorithm. The algorithm was compared to manually obtained gradings of these images. Results: The sensitivity of diagnosis for DR was 100%, with specificity of 90% and the sensitivity of precise MA localization was 97%, at an average number of 5 false positives per image. Discussion and Conclusion: Sensitivity and specificity of this algorithm make it one of the best methods in this field. Using the local radon transform in this algorithm eliminates the noise sensitivity for MA detection in retinal image analysis.

  14. Simultaneous macula detection and optic disc boundary segmentation in retinal fundus images

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    Girard, Fantin; Kavalec, Conrad; Grenier, Sébastien; Ben Tahar, Houssem; Cheriet, Farida

    2016-03-01

    The optic disc (OD) and the macula are important structures in automatic diagnosis of most retinal diseases inducing vision defects such as glaucoma, diabetic or hypertensive retinopathy and age-related macular degeneration. We propose a new method to detect simultaneously the macula and the OD boundary. First, the color fundus images are processed to compute several maps highlighting the different anatomical structures such as vessels, the macula and the OD. Then, macula candidates and OD candidates are found simultaneously and independently using seed detectors identified on the corresponding maps. After selecting a set of macula/OD pairs, the top candidates are sent to the OD segmentation method. The segmentation method is based on local K-means applied to color coordinates in polar space followed by a polynomial fitting regularization step. Pair scores are updated, resulting in the final best macula/OD pair. The method was evaluated on two public image databases: ONHSD and MESSIDOR. The results show an overlapping area of 0.84 on ONHSD and 0.90 on MESSIDOR, which is better than recent state of the art methods. Our segmentation method is robust to contrast and illumination problems and outputs the exact boundary of the OD, not just a circular or elliptical model. The macula detection has an accuracy of 94%, which again outperforms other macula detection methods. This shows that combining the OD and macula detections improves the overall accuracy. The computation time for the whole process is 6.4 seconds, which is faster than other methods in the literature.

  15. Detailed Morphological Changes of Foveoschisis in Patient with X-Linked Retinoschisis Detected by SD-OCT and Adaptive Optics Fundus Camera

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    Keiichiro Akeo

    2015-01-01

    Full Text Available Purpose. To report the morphological and functional changes associated with a regression of foveoschisis in a patient with X-linked retinoschisis (XLRS. Methods. A 42-year-old man with XLRS underwent genetic analysis and detailed ophthalmic examinations. Functional assessments included best-corrected visual acuity (BCVA, full-field electroretinograms (ERGs, and multifocal ERGs (mfERGs. Morphological assessments included fundus photography, spectral-domain optical coherence tomography (SD-OCT, and adaptive optics (AO fundus imaging. After the baseline clinical data were obtained, topical dorzolamide was applied to the patient. The patient was followed for 24 months. Results. A reported RS1 gene mutation was found (P203L in the patient. At the baseline, his decimal BCVA was 0.15 in the right and 0.3 in the left eye. Fundus photographs showed bilateral spoke wheel-appearing maculopathy. SD-OCT confirmed the foveoschisis in the left eye. The AO images of the left eye showed spoke wheel retinal folds, and the folds were thinner than those in fundus photographs. During the follow-up period, the foveal thickness in the SD-OCT images and the number of retinal folds in the AO images were reduced. Conclusions. We have presented the detailed morphological changes of foveoschisis in a patient with XLRS detected by SD-OCT and AO fundus camera. However, the findings do not indicate whether the changes were influenced by topical dorzolamide or the natural history.

  16. Pengaruh Senam Nifas terhadap Penurunan Tinggi Fundus Uteri pada Ibu Post Partum di RSUP DR. M. Djamil Padang

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    Nurniati Tianastia Rullynil

    2014-09-01

    Full Text Available AbstrakPerdarahan merupakan penyebab utama kesakitan dan kematian ibu pada masa nifas, dimana 50%-60% karena kegagalan miometrium berkontraksi secara sempurna. Salah satu asuhan untuk memaksimalkan kontraksi uterus pada masa nifas adalah dengan melaksanakan senam nifas, guna mempercepat proses involusi uteri. Tujuan penelitian ini adalah untuk mengetahui pengaruh senam nifas terhadap penurunan tinggi fundus uteri (TFU pada ibu post partum. Penelitian ini merupakan studi eksperimental dengan Post Test Only Control Group Design. Alat yang digunakan dalam penelitian berupa kaliper pelvimetri. Diberikan perlakuan senam nifas pada kelompok intervensi dan tidak senam nifas pada kelompok kontrol, kemudian dilakukan pengukuran tinggi fundus uteri hari ke-1, hari ke-3 dan hari ke-6. Data dianalisa menggunakan Uji General Linier Model (GLM. Rerata TFU hari ke-1 pada kelompok intervensi 12,37±0,72 dan 12,42±0,54 pada kelompok kontrol. Rerata TFU hari ke-3 pada kelompok intervensi 9,00±0,94 dan 9,87±0,75 pada kelompok kontrol. Sedangkan rerata TFU hari ke-6 pada kelompok intervensi 5,72±0,88 dan 7,37±0,68 pada kelompok kontrol. Terdapat perbedaan yang signifikan penurunan tinggi fundus uteri antara kedua kelompok pada hari ke-3 (p=0,00 dan hari ke 6 (p=0,00. Dari hasil penelitian dapat disimpulkan bahwa senam nifas berpengaruh terhadap penurunan tinggi fundus uteri. Penurunan tinggi fundus uteri pada kelompok intervensi lebih turun dibanding kelompok kontrol.Kata kunci: senam nifas, tinggi fundus uteri, post partumAbstractHemorrhage is a major cause of maternal morbidity and mortality in the puerperium, about 50%-60% of hemorrhage occurs due to failure of myometrium to contract completely. One care to maximaze uterine contraction during the puerperium is by implementing parturition gymnastics in order to accelarate the process of uterine involution. The purpose of this study was to determine the effect of parturition gymnastics on a decreasing of

  17. CORRELATION OF FUNDUS CHANGES IN RELATION TO REFRACTIVE ERROR IN PATIENTS WITH MYOPIA- A CLINICAL PROSPECTIVE STUDY

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    Balasubramanian M. Manickavelu

    2018-01-01

    Full Text Available BACKGROUND Retina is unique among the complex element of the central nervous system and the special senses. It may be readily viewed during life and it is sufficiently transparent, so that alterations within and adjacent to it may be observed in vivo. The peripheral retina owing to its thinness comparing to that of the central part, poorly-developed retinal cells, absence of large blood vessels, relatively insensitive to light, less resistance to traction, forms a seat for various lesions, which are potentially dangerous for the vision. It is in myopia that we meet the most frequent and the most obvious anomalies in the fundus changes, which bear some relation to the degree of myopia and appeal to be concerned with it either as a cause or effect or perhaps both. The aim of our study is to correlate fundus changes in relation to refractive error in patients with myopia. MATERIALS AND METHODS In our study, 100 cases of myopic (-6D:50 cases patients were selected. Detailed evaluation done. History of refractive error includes duration, age at which spectacles were worn for the first time. Time of last change of spectacles, family history of myopia, history of other symptoms like progressive loss of vision, defective vision related to day or night, sudden loss of vision, flashes and floaters. Anterior segment was examined followed by the recording of initial visual acuity and the best corrected visual acuity was noted. IOP was measured for all the cases using Schiotz tonometry. Axial length was measured in all the cases. Fundus examined with direct ophthalmoscope, indirect ophthalmoscope, 3 mirror and 90D lens. Bscan was done in few cases. The media, disc, vessels, macula and the surrounding retina were examined. The periphery was examined with indentation method. The various fundus features and pathological lesions in different degrees of myopia were noted. RESULTS Females were comparatively more affected. Highest incidence was seen in the younger

  18. [Evaluation of diabetic retinopathy screening using non-mydriatic fundus camera performed by physicians' assistants in the endocrinology service].

    Science.gov (United States)

    Barcatali, M-G; Denion, E; Miocque, S; Reznik, Y; Joubert, M; Morera, J; Rod, A; Mouriaux, F

    2015-04-01

    Since 2010, the High Authority for health (HAS) recommends the use of non-mydriatic fundus camera for diabetic retinopathy screening. The purpose of this study is to evaluate the results of screening for diabetic retinopathy using the non-mydriatic retinal camera by a physician's assistant in the endocrinology service. This is a retrospective study of all diabetic patients hospitalized in the endocrinology department between May 2013 and November 2013. For each endocrinology patient requiring screening, a previously trained physician's assistant performed fundus photos. The ophthalmologist then provided a written interpretation of the photos on a consultant's sheet. Of the 120 patients screened, 40 (33.3%) patients had uninterpretable photos. Among the 80 interpretable photos, 64 (53.4%) patients had no diabetic retinopathy, and 16 (13.3%) had diabetic retinopathy. No patient had diabetic maculopathy. Specific quality criteria were established by the HAS for screening for diabetic retinopathy using the non-mydriatic retinal camera in order to ensure sufficient sensitivity and specificity. In our study, the two quality criteria were not achieved: the rates of uninterpretable photos and the total number of photos analyzed in a given period. In our center, we discontinued this method of diabetic retinopathy screening due to the high rate of uninterpretable photos. Due to the logistic impossibility of the ophthalmologists taking all the fundus photos, we proposed that the ophthalmic nurses take the photos. They are better trained in the use of the equipment, and can confer directly with an ophthalmologist in questionable cases and to obtain pupil dilation as necessary. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  19. Diagnostic accuracy of direct ophthalmoscopy for detection of diabetic retinopathy using fundus photographs as a reference standard.

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    Ahsan, Shahid; Basit, Abdul; Ahmed, Kazi Rumana; Ali, Liaquat; Shaheen, Fariha; Ulhaque, Muhammad Saif; Fawwad, Asher

    2014-01-01

    To determine the diagnostic accuracy of direct ophthalmoscopy for the presence and severity of diabetic retinopathy (DR) using fundus photographs as a reference standard. Patients with type 2 diabetes attending the outpatient department (OPD) of a tertiary care diabetes center, from October 2009 to March 2010 were recruited in the study after obtaining signed informed consent. Patients with type 1 diabetes and gestational diabetes or having eye problems were excluded. After checking visual acuity, direct ophthalmoscopy of each eye was done by diabetologist, followed by photography of two fields of retina by fundus camera. DR was graded by a retinal specialist, according to International Diabetic Retinopathy Disease Severity Scale. According to severity, patients with DR were grouped into non-sight threatening diabetic retinopathy (NSTDR) and sight threatening diabetic retinopathy (STDR). Sensitivity and specificity of direct ophthalmoscopy for detection of any retinopathy, NSTDR and STDR was calculated. A total of 728 eyes were examined by direct ophthalmoscopy as well as fundus photography. Sensitivity (95% CI) of direct ophthalmoscopy for any retinopathy, NSTDR and STDR was found to be 55.67% (50.58-60.78), 37.63% (32.67-42.59) and 68.25% (63.48-73.02) respectively. Whereas, specificity of direct ophthalmoscopy was found to be 76.78% (72.45-81.11), 71.27% (CI: 66.63-75.91) and 90.0% (86.93-93.07) for any retinopathy, NSTDR and STDR respectively. The sensitivity and specificity of direct ophthalmoscopy performed by the diabetologist for the presence and severity of DR was lower compared to the recommended level of sensitivity and specificity of a screening test of DR. Copyright © 2014 Diabetes India. Published by Elsevier Ltd. All rights reserved.

  20. Comparison of subjective and objective methods to determine the retinal arterio-venous ratio using fundus photography

    Directory of Open Access Journals (Sweden)

    Rebekka Heitmar

    2015-10-01

    Conclusion: Grader education and experience leads to inter-grader differences but more importantly, subjective grading is not capable to pick up subtle differences across healthy individuals and does not represent true AVR when compared with an objective assessment method. Technology advancements mean we no longer rely on opthalmoscopic evaluation but can capture and store fundus images with retinal cameras, enabling us to measure vessel calibre more accurately compared to visual estimation; hence it should be integrated in optometric practise for improved accuracy and reliability of clinical assessments of retinal vessel calibres.

  1. Nerve canals at the fundus of the internal auditory canal on high-resolution temporal bone CT

    International Nuclear Information System (INIS)

    Ji, Yoon Ha; Youn, Eun Kyung; Kim, Seung Chul

    2001-01-01

    To identify and evaluate the normal anatomy of nerve canals in the fundus of the internal auditory canal which can be visualized on high-resolution temporal bone CT. We retrospectively reviewed high-resolution (1 mm thickness and interval contiguous scan) temporal bone CT images of 253 ears in 150 patients who had not suffered trauma or undergone surgery. Those with a history of uncomplicated inflammatory disease were included, but those with symptoms of vertigo, sensorineural hearing loss, or facial nerve palsy were excluded. Three radiologists determined the detectability and location of canals for the labyrinthine segment of the facial, superior vestibular and cochlear nerve, and the saccular branch and posterior ampullary nerve of the inferior vestibular nerve. Five bony canals in the fundus of the internal auditory canal were identified as nerve canals. Four canals were identified on axial CT images in 100% of cases; the so-called singular canal was identified in only 68%. On coronal CT images, canals for the labyrinthine segment of the facial and superior vestibular nerve were seen in 100% of cases, but those for the cochlear nerve, the saccular branch of the inferior vestibular nerve, and the singular canal were seen in 90.1%, 87.4% and 78% of cases, respectiveIy. In all detectable cases, the canal for the labyrinthine segment of the facial nerve was revealed as one which traversed anterolateralIy, from the anterosuperior portion of the fundus of the internal auditory canal. The canal for the cochlear nerve was located just below that for the labyrinthine segment of the facial nerve, while that canal for the superior vestibular nerve was seen at the posterior aspect of these two canals. The canal for the saccular branch of the inferior vestibular nerve was located just below the canal for the superior vestibular nerve, and that for the posterior ampullary nerve, the so-called singular canal, ran laterally or posteolateralIy from the posteroinferior aspect of

  2. Nerve canals at the fundus of the internal auditory canal on high-resolution temporal bone CT

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Yoon Ha; Youn, Eun Kyung; Kim, Seung Chul [Sungkyunkwan Univ., School of Medicine, Seoul (Korea, Republic of)

    2001-12-01

    To identify and evaluate the normal anatomy of nerve canals in the fundus of the internal auditory canal which can be visualized on high-resolution temporal bone CT. We retrospectively reviewed high-resolution (1 mm thickness and interval contiguous scan) temporal bone CT images of 253 ears in 150 patients who had not suffered trauma or undergone surgery. Those with a history of uncomplicated inflammatory disease were included, but those with symptoms of vertigo, sensorineural hearing loss, or facial nerve palsy were excluded. Three radiologists determined the detectability and location of canals for the labyrinthine segment of the facial, superior vestibular and cochlear nerve, and the saccular branch and posterior ampullary nerve of the inferior vestibular nerve. Five bony canals in the fundus of the internal auditory canal were identified as nerve canals. Four canals were identified on axial CT images in 100% of cases; the so-called singular canal was identified in only 68%. On coronal CT images, canals for the labyrinthine segment of the facial and superior vestibular nerve were seen in 100% of cases, but those for the cochlear nerve, the saccular branch of the inferior vestibular nerve, and the singular canal were seen in 90.1%, 87.4% and 78% of cases, respectiveIy. In all detectable cases, the canal for the labyrinthine segment of the facial nerve was revealed as one which traversed anterolateralIy, from the anterosuperior portion of the fundus of the internal auditory canal. The canal for the cochlear nerve was located just below that for the labyrinthine segment of the facial nerve, while that canal for the superior vestibular nerve was seen at the posterior aspect of these two canals. The canal for the saccular branch of the inferior vestibular nerve was located just below the canal for the superior vestibular nerve, and that for the posterior ampullary nerve, the so-called singular canal, ran laterally or posteolateralIy from the posteroinferior aspect of

  3. Inherited Retinal Degenerative Disease Registry

    Science.gov (United States)

    2017-09-13

    Eye Diseases Hereditary; Retinal Disease; Achromatopsia; Bardet-Biedl Syndrome; Bassen-Kornzweig Syndrome; Batten Disease; Best Disease; Choroidal Dystrophy; Choroideremia; Cone Dystrophy; Cone-Rod Dystrophy; Congenital Stationary Night Blindness; Enhanced S-Cone Syndrome; Fundus Albipunctatus; Goldmann-Favre Syndrome; Gyrate Atrophy; Juvenile Macular Degeneration; Kearns-Sayre Syndrome; Leber Congenital Amaurosis; Refsum Syndrome; Retinitis Pigmentosa; Retinitis Punctata Albescens; Retinoschisis; Rod-Cone Dystrophy; Rod Dystrophy; Rod Monochromacy; Stargardt Disease; Usher Syndrome

  4. Factores asociados al estadio clínico avanzado en el inicio de la terapia antirretroviral

    Directory of Open Access Journals (Sweden)

    Eduardo Warley

    2012-10-01

    Full Text Available A fin de evaluar la frecuencia y posibles factores asociados a la presencia de estadio clínico avanzado al inicio de terapia antirretroviral (ECAITA, efectuamos un análisis retrospectivo de datos de dos cohortes prospectivas de pacientes infectados por HIV que iniciaron terapia antirretroviral (sin tratamiento anterior entre 2005 y 2009. Se analizaron las historias clínicas de 264 pacientes, 123 mujeres (46.6% y 141 hombres (53.4%. La mediana de edad fue de 37.7 años. Observamos ECAITA en 132 casos (50%, de los cuales 102 (77.2% se asociaron a diagnóstico tardío de infección por HIV y 30 (22.8% a pacientes con diagnóstico previo no retenidos en el cuidado clínico de la salud. La mediana de células CD4 fue 120/ml y de carga viral 58 038 copias/ml. El recuento de células CD4 era inferior a 200 cel/ml en 174 pacientes (71.3%. Los hombres presentaron ECAITA con mayor frecuencia que las mujeres (59.8% vs. 40.2%, en quienes el diagnóstico se realizó durante el control de un embarazo en el 25.2% de los casos. Consumo elevado de alcohol (p 0.006, ser soltero (p 0.04 y nivel de educación menor al secundario completo (p 0.008 se asociaron a ECAITA en el análisis bivariado. Ser de sexo masculino (p 0.003 fue el único factor asociado tanto en el análisis bivariado como en el multivariado. Nuestros datos refuerzan la necesidad de expandir el testeo para HIV y deberían impulsar a definir acciones programáticas que promuevan el ingreso precoz al cuidado de la infección por HIV.

  5. Papilomavirus humanos y otros factores asociados al desarrollo de lesiones cervicouterinas en mujeres cubanas

    Directory of Open Access Journals (Sweden)

    Yudira Soto Brito

    2016-02-01

    Full Text Available Objetivo: Determinar la circulación de genotipos de Papilomavirus humanos (PVH y los factores sociodemográficos, epidemiológicos y clínicos asociados con la presencia de lesiones intraepiteliales cervicales en un grupo de mujeres cubanas. Materiales y Métodos: Estudio de corte transversal en población femenina de 4 municipios de La Habana. Se incluyeron 519 mujeres entre 15 y 59 años con una citología cervical negativa en los dos años anteriores al estudio. Se les realizó citología cervical y detección de PVH. Para la detección viral se realizó Reacción en Cadena de la Polimerasa (PCR empleando los oligonucleótidos MY09/11. El genotipado se realizó mediante hibridación Dot Blot. Resultados: El 41,6% de la población estudiada se diagnosticó con citología con citología positiva, de ellas el 58,8% con lesiones de alto grado. En el 66,3% de las mujeres estudiadas se detectó algún tipo de PVH, asociado significativamente con la citología positiva. Se identificaron 30 genotipos diferentes de PVH, con predominio de los genotipos oncogénicos PVH 16 (41,0%, 31 (11,6% y 18 (10,2%. Los predictores de riesgo para la infección con estos genotipos fueron: el inicio de las relaciones sexuales antes de los 15 años, la menarquía entre 10 y 14 años, el consumo de cigarrillos y de anticonceptivos orales. En mujeres menores de 20 años predominaron las lesiones de alto grado. Conclusiones: Los resultados del presente estudio apoyan el uso de la vacunación contra PVH y sugiere la realización de investigaciones basadas en estudios virológicos y citológicos en mujeres menores de 25 años.

  6. Factores clínicos asociados a multirresistencia bacteriana en un hospital de cuarto nivel

    Directory of Open Access Journals (Sweden)

    Eliana Saldarriaga Quintero

    Full Text Available Introducción: Las infecciones causadas por bacterias multirresistentes aumentan la morbilidad, la mortalidad, los costos de la atención y ocasionan dificultades para el tratamiento. Conocer los factores asociados a la infección por bacterias multirresistentes es clave para una adecuada vigilancia y control que permita mejorar la atención de los pacientes en los hospitales. Objetivo: Determinar factores clínicos asociados a infección por bacterias multirresistentes en un hospital de alta complejidad. Materiales y métodos: Se realizó un estudio de casos y controles utilizando las historias clínicas de pacientes hospitalizados. La selección de los controles se hizo por muestreo aleatorizado simple. Los análisis de los datos se realizaron en el software SPSS 21.0, se calcularon medidas descriptivas y de asociación (U de Mann-Whitney, chi-cuadrado y OR, y se realizó un modelo multivariado mediante regresión logística para el cálculo del OR ajustado. Resultados: Se encontraron asociaciones significativas con inmunosupresión por medicamentos (OR = 2,58, trasplante (OR = 2,88, hospitalización (OR = 1,73 o cirugía (OR = 1,78 en los 3 meses previos a la infección, diálisis (OR = 3,53, catéter venoso central (OR = 2,16, nutrición parenteral (OR = 2,06 y terapia antibiótica en las 48 h previas a la infección (OR = 1,86. En el modelo multivariado fueron importantes la hospitalización previa (OR = 1,83 y tener EPOC (OR = 3,07. Conclusiones: La hospitalización previa y la EPOC son factores de riesgo independientes para adquirir infección por bacterias multirresistentes. Además, aunque no fue posible estimar el riesgo debido a que no se encontraron controles expuestos, la nutrición parenteral y el uso de quinolonas en las 48 h previas a la infección fueron importantes en la ocurrencia del evento.

  7. Factores asociados a la prevalencia de tuberculosis en el distrito de Cartagena

    Directory of Open Access Journals (Sweden)

    Irma Yolanda Castillo Ávila

    2013-08-01

    Full Text Available Objetivo: determinar los factores asociados a la prevalencia de tuberculosis en el Distrito de Cartagena. Metodología: se realizó un estudio analítico de casos y controles. La población objeto de estudio estuvo constituida por 240 personas diagnosticadas con tuberculosis en Cartagena. Se definió como caso toda persona ingresada al programa de control de tuberculosis del Distrito. Se realizó control comunitario a vecinos cercanos en la misma localidad, del mismo sexo, con más o menos cinco años de edad que el caso, quienes nunca habían padecido la enfermedad y sin síntomas respiratorios. Se almacenó los datos en el programa estadístico SPSSS versión 20.0, se calcularon razones de disparidad para estimar la relación entre variables. Resultados: participaron del estudio 303 personas (101 casos y 202 controles. Con un promedio de edad de 35.7 años (DE=17.9, para casos y 40.3 años (DE=20.3 para controles. Se encontraron como factores asociados a la presencia de tuberculosis el estado de vacunación con BCG (OR=0.11 IC 95% 0.05 - 0.22, tener pareja estable (OR= 0.54 IC 95% 0.30 - 0.96 y el antecedente familiar de Tuberculosis. (OR=20.97 IC 95%: 6.26 - 70.24. Conclusiones: el fortalecimiento de los programas de promoción y prevención de tuberculosis a nivel comunitario y familiar, puede mejorar el estado de salud de los individuos. La aplicación de prácticas como la vacunación de niños y niñas y las medidas preventivas en el hogar son necesarias para prevenir la aparición de la enfermedad.

  8. Primer registro de Triatoma infestans (Klug (Hemiptera: Reduviidae asociado a nidos de loros barranqueros (Cyanoliseus patagonus (Aves: Psittacidae

    Directory of Open Access Journals (Sweden)

    María L. HERNÁNDEZ

    2015-01-01

    Full Text Available Triatoma infestans es el vector más importante de la enfermedad de Chagas de la Argentina. Se cita por primera vez la presencia de T. infestans (Klug (Hemiptera: Reduviidae asociado a nidos de loro barranquero Cyanoliseus patagonus (Psittasiformes: Psittacidae construidos en viviendas de adobe abandonadas. Se discuten las posibles implicancias de este hallazgo para la vigilancia entomológica del vector.

  9. Factores asociados a insuficiencia renal postoperatoria en cirugía de revascularización miocárdica

    Directory of Open Access Journals (Sweden)

    Albert F. Guerrero B.

    2016-05-01

    Conclusiones: En quienes se realizó revascularización miocárdica los factores asociados a la presentación de insuficiencia renal postoperatoria fueron comorbilidades que se relacionaron con daño renal progresivo dentro y fuera del contexto de la cirugía. Esto implica que las estrategias para minimizar este evento estarán enfocadas a identificar de manera oportuna a estos pacientes y proporcionarles nefroprotección adecuada.

  10. Factores asociados a la calificación del Examen Nacional de Medicina 2012 en internos de la UNMSM

    Directory of Open Access Journals (Sweden)

    Fernando Ricardo Arenas-Significación

    2014-01-01

    Full Text Available Introducción: El Examen Nacional de Medicina (ENAM es una herramienta que mide los conocimientos y el raciocinio clínico del interno como una forma de aproximarse a evaluar la calidad educativa. Objetivo: Determinar los factores asociados a la calificación del ENAM 2012 en internos de la Universidad Nacional Mayor de San Marcos (UNMSM. Diseño: Estudio transversal. Lugar: Facultad de Medicina Humana de la UNMSM, Lima, Perú. Participantes: Internos de Medicina Humana 2012. Intervenciones: Se analizó fuentes secundarias con el método de regresión logística binaria. Se determinó los coeficientes de correlación de Pearson y Spearman, así como la prueba t student. Principales medidas de resultados: Promedios de las calificaciones del ENAM, pertenencia a la promoción ingresante, sede hospitalaria de internado, orden de mérito según promedio ponderado universitario (PPU. Resultados: Los factores asociados a un mejor puntaje en el ENAM fueron pertenecer a la promoción ingresante 2006, realizar internado en EsSalud y ubicarse en el tercio superior y medio. Conclusiones: La pertenencia a la promoción ingresante 2006, la sede hospitalaria de internado y el orden de mérito según el PPU fueron factores asociados a obtener una calificación mayor o igual a trece en el ENAM 2012.

  11. Factores asociados con la seropositividad a Brucella canis en criaderos caninos de dos regiones de Antioquia, Colombia

    Directory of Open Access Journals (Sweden)

    Laura Castrillón-Salazar

    2013-10-01

    Full Text Available El objetivo fue determinar la seroprevalencia a Brucella canis en perros y humanos convivientes en criaderos caninos y explorar los factores de riesgo asociados a la seropositividad. Se tomaron 20 criaderos, en los cuales se realizó diagnóstico serológico por PARP-2ME de 428 caninos y 91 humanos. Se aplicó una encuesta para determinar los factores de riesgo y se analizaron los datos mediante regresión logística. Se determinó una seroprevalencia de 15% en caninos y 9% en humanos convivientes. Se determinaron como factores asociados a la seropositividad canina el historial de seropositividad canina, conservar los caninos seropositivos, historial de aborto, higiene y protección del operario deficientes durante el servicio reproductivo, y procedimiento inseguro durante la atención de abortos. Como factores protectores se establecieron la ubicación rural de los criaderos, facilidad de aseo de los caniles, PARP-2ME premonta, y procedimiento seguro durante la atención de partos. En humanos se determinaron factores asociados: criaderos ubicados en el Valle Aburrá y de tipo urbano.

  12. A Deep Learning Algorithm for Prediction of Age-Related Eye Disease Study Severity Scale for Age-Related Macular Degeneration from Color Fundus Photography.

    Science.gov (United States)

    Grassmann, Felix; Mengelkamp, Judith; Brandl, Caroline; Harsch, Sebastian; Zimmermann, Martina E; Linkohr, Birgit; Peters, Annette; Heid, Iris M; Palm, Christoph; Weber, Bernhard H F

    2018-04-10

    Age-related macular degeneration (AMD) is a common threat to vision. While classification of disease stages is critical to understanding disease risk and progression, several systems based on color fundus photographs are known. Most of these require in-depth and time-consuming analysis of fundus images. Herein, we present an automated computer-based classification algorithm. Algorithm development for AMD classification based on a large collection of color fundus images. Validation is performed on a cross-sectional, population-based study. We included 120 656 manually graded color fundus images from 3654 Age-Related Eye Disease Study (AREDS) participants. AREDS participants were >55 years of age, and non-AMD sight-threatening diseases were excluded at recruitment. In addition, performance of our algorithm was evaluated in 5555 fundus images from the population-based Kooperative Gesundheitsforschung in der Region Augsburg (KORA; Cooperative Health Research in the Region of Augsburg) study. We defined 13 classes (9 AREDS steps, 3 late AMD stages, and 1 for ungradable images) and trained several convolution deep learning architectures. An ensemble of network architectures improved prediction accuracy. An independent dataset was used to evaluate the performance of our algorithm in a population-based study. κ Statistics and accuracy to evaluate the concordance between predicted and expert human grader classification. A network ensemble of 6 different neural net architectures predicted the 13 classes in the AREDS test set with a quadratic weighted κ of 92% (95% confidence interval, 89%-92%) and an overall accuracy of 63.3%. In the independent KORA dataset, images wrongly classified as AMD were mainly the result of a macular reflex observed in young individuals. By restricting the KORA analysis to individuals >55 years of age and prior exclusion of other retinopathies, the weighted and unweighted κ increased to 50% and 63%, respectively. Importantly, the algorithm

  13. Modification of a Kowa RC-2 fundus camera for self-photography without the use of mydriatics. [for blood vessel monitoring during space flight

    Science.gov (United States)

    Philpott, D. E.; Harrison, G.; Turnbill, C.; Bailey, P. F.

    1979-01-01

    Research on retinal circulation during space flight required the development of a simple technique to provide self monitoring of blood vessel changes in the fundus without the use of mydriatics. A Kowa RC-2 fundus camera was modified for self-photography by the use of a bite plate for positioning and cross hairs for focusing the subject's retina relative to the film plane. Dilation of the pupils without the use of mydriatics was accomplished by dark-adaption of the subject. Pictures were obtained without pupil constriction by the use of a high speed strobe light. This method also has applications for clinical medicine.

  14. Canine and feline fundus photography and videography using a nonpatented 3D printed lens adapter for a smartphone.

    Science.gov (United States)

    Espinheira Gomes, Filipe; Ledbetter, Eric

    2018-05-11

    To describe an indirect funduscopy imaging technique for dogs and cats using low cost and widely available equipment: a smartphone, a three-dimensional (3D) printed indirect lens adapter, and a 40 diopters (D) indirect ophthalmoscopy lens. Fundus videography was performed in dogs and cats using a 40D indirect ophthalmoscopy lens and a smartphone fitted with a 3D printed indirect lens adapter. All animals were pharmacologically dilated with topical tropicamide 1% solution. Eyelid opening and video recording were performed using standard binocular indirect ophthalmoscopy technique. All videos were uploaded to a computer, and still images were selected and acquired for archiving purposes. Fundic images were manipulated to represent the true anatomy of the fundus. It was possible to promptly obtain good quality images from normal and diseased retinas using the nonpatented 3D printed, lens adapter for a smartphone. Fundic imaging using a smartphone can be performed with minimal investment. This simple imaging modality can be used by veterinary ophthalmologists and general practitioners to acquire, archive, and share images of the retina. The quality of images obtained will likely improve with developments in smartphone camera software and hardware. © 2018 American College of Veterinary Ophthalmologists.

  15. Supervised retinal vessel segmentation from color fundus images based on matched filtering and AdaBoost classifier.

    Directory of Open Access Journals (Sweden)

    Nogol Memari

    Full Text Available The structure and appearance of the blood vessel network in retinal fundus images is an essential part of diagnosing various problems associated with the eyes, such as diabetes and hypertension. In this paper, an automatic retinal vessel segmentation method utilizing matched filter techniques coupled with an AdaBoost classifier is proposed. The fundus image is enhanced using morphological operations, the contrast is increased using contrast limited adaptive histogram equalization (CLAHE method and the inhomogeneity is corrected using Retinex approach. Then, the blood vessels are enhanced using a combination of B-COSFIRE and Frangi matched filters. From this preprocessed image, different statistical features are computed on a pixel-wise basis and used in an AdaBoost classifier to extract the blood vessel network inside the image. Finally, the segmented images are postprocessed to remove the misclassified pixels and regions. The proposed method was validated using publicly accessible Digital Retinal Images for Vessel Extraction (DRIVE, Structured Analysis of the Retina (STARE and Child Heart and Health Study in England (CHASE_DB1 datasets commonly used for determining the accuracy of retinal vessel segmentation methods. The accuracy of the proposed segmentation method was comparable to other state of the art methods while being very close to the manual segmentation provided by the second human observer with an average accuracy of 0.972, 0.951 and 0.948 in DRIVE, STARE and CHASE_DB1 datasets, respectively.

  16. A multi-scale tensor voting approach for small retinal vessel segmentation in high resolution fundus images.

    Science.gov (United States)

    Christodoulidis, Argyrios; Hurtut, Thomas; Tahar, Houssem Ben; Cheriet, Farida

    2016-09-01

    Segmenting the retinal vessels from fundus images is a prerequisite for many CAD systems for the automatic detection of diabetic retinopathy lesions. So far, research efforts have concentrated mainly on the accurate localization of the large to medium diameter vessels. However, failure to detect the smallest vessels at the segmentation step can lead to false positive lesion detection counts in a subsequent lesion analysis stage. In this study, a new hybrid method for the segmentation of the smallest vessels is proposed. Line detection and perceptual organization techniques are combined in a multi-scale scheme. Small vessels are reconstructed from the perceptual-based approach via tracking and pixel painting. The segmentation was validated in a high resolution fundus image database including healthy and diabetic subjects using pixel-based as well as perceptual-based measures. The proposed method achieves 85.06% sensitivity rate, while the original multi-scale line detection method achieves 81.06% sensitivity rate for the corresponding images (p<0.05). The improvement in the sensitivity rate for the database is 6.47% when only the smallest vessels are considered (p<0.05). For the perceptual-based measure, the proposed method improves the detection of the vasculature by 7.8% against the original multi-scale line detection method (p<0.05). Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. MACULAR ATROPHY FINDINGS BY OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY COMPARED WITH FUNDUS AUTOFLUORESCENCE IN TREATED EXUDATIVE AGE-RELATED MACULAR DEGENERATION.

    Science.gov (United States)

    Takasago, Yukari; Shiragami, Chieko; Kobayashi, Mamoru; Osaka, Rie; Ono, Aoi; Yamashita, Ayana; Tsujikawa, Akitaka; Hirooka, Kazuyuki

    2017-11-28

    To compare the areas of choriocapillaris (CC) nonperfusion and macular atrophy (MA) in treated exudative age-related macular degeneration. This was a prospective, observational, cross-sectional study. Forty-four eyes exhibiting MA (42 patients with age-related macular degeneration), with a dry macula, underwent fundus autofluorescence and optical coherence tomography angiography. The area of MA detected by fundus autofluorescence and CC nonperfusion detected by optical coherence tomography angiography was measured using image analysis software. The rates of concordance between the MA and CC nonperfusion areas were calculated. We qualitatively and quantitatively compared the areas of MA and CC nonperfusion in age-related macular degeneration eyes. The mean areas of MA and CC nonperfusion were 5.95 ± 4.50 mm and 10.66 ± 7.05 mm, respectively (paired t-test, P autofluorescence matching optical coherence tomography angiography showed that the CC nonperfusion area was almost included in the MA area. The mean concordance rate for the MA area inside the CC nonperfusion area was 87.7 ± 13.9%. The MA and CC nonperfusion areas markedly overlapped. The area of CC nonperfusion correlated with the MA area. Choroidal ischemia might be involved in the pathogenesis of MA in treated age-related macular degeneration.This is an open access article distributed under the Creative Commons Attribution License 4.0 (CCBY), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

  18. Serial imaging and structure-function correlates of high-density rings of fundus autofluorescence in retinitis pigmentosa.

    Science.gov (United States)

    Robson, Anthony G; Tufail, Adnan; Fitzke, Fred; Bird, Alan C; Moore, Anthony T; Holder, Graham E; Webster, Andrew R

    2011-09-01

    To document the evolution and functional and structural significance of parafoveal rings of high-density fundus autofluorescence (AF) in patients with retinitis pigmentosa and preserved visual acuity. Fifty-two patients with nonsyndromic retinitis pigmentosa or Usher syndrome, who had a parafoveal ring of high-density AF and a visual acuity of 20/30 or better, were ascertained. All had international standard full-field electroretinography and pattern electroretinography. Autofluorescence imaging was repeated in 30 patients after periods of up to 9.3 years. Of the 52 patients, 35 underwent optical coherence tomography. Progressive constriction of the ring was detected in 17 patients. Ring radius reduced by up to 40% at a mean rate of between 0.8% and 15.8% per year. In 1 patient, a small ring was replaced by irregular AF; visual acuity deteriorated over the same period. There was a high correspondence between the lateral extent of the preserved optical coherence tomography inner segment/outer segment band and the diameter of the ring along the same optical coherence tomographic scan plane (slope, 0.9; r = 0.97; P retina and preserved photopic function. Serial fundus AF may provide prognostic indicators for preservation of central acuity and potentially assist in the identification and evaluation of patients suitable for treatment aimed at preservation of remaining function.

  19. A gene for late-onset fundus flavimaculatus with macular dystrophy maps to chromosome 1p13

    Energy Technology Data Exchange (ETDEWEB)

    Gerber, S.; Rozet, J.M.; Bonneau, D.; Souied, E.; Camuzat, A.; Munnich, A.; Kaplan, J. [Hopital des Enfants Malades, Paris (France); Dufier, J.L. [Hopital Laeennec, Paris (France); Amalric, P. [Consultation d`Ophtalmologie, Albi (France); Weissenbach, J. [Genethon, Evry (France)

    1995-02-01

    Fundus flavimaculatus with macular dystrophy is an autosomal recessive disease responsible for a progressive loss of visual acuity in adulthood, with pigmentary changes of the macula, perimacular flecks, and atrophy of the retinal pigmentary epithelium. Since this condition shares several clinical features with Stargardt disease, which has been mapped to chromosome 1p21-p13, we tested the disease for linkage to chromosome 1p. We report the mapping of the disease locus to chromosome 1p13-p21, in the genetic interval defined by loci D1S435 and D1S415, in four multiplex families (maximum lod score 4.79 at recombination fraction 0 for probe AFM217xb2 at locus D1S435). Thus, despite differences in the age at onset, clinical course, and severity, fundus flavimaculatus with macular dystrophy and Stargardt disease are probably allelic disorders. This result supports the view that allelic mutations produce a continuum of macular dystrophies, with onset in early childhood to late adulthood. 16 refs., 3 figs., 1 tab.

  20. Agreement between optical coherence tomography and fundus fluorescein angiography in post-cataract surgery cystoid macular edema

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    Mitne Somaia

    2003-01-01

    Full Text Available PURPOSE: To evaluate the agreement between optical coherence tomography (OCT and fundus fluorescein angiography (FFA regarding the detection of cystoid macular edema (CME following cataract surgery. METHODS: Retrospective comparative observational series of 25 eyes with suspected CME. Patients with low visual acuity and alterations in fundus biomicroscopy after cataract surgery underwent OCT scanning followed by FFA on the same visit. The diagnosis of CME was established considering fluorescein leakage on FFA and retinal thickness and/or cystoid spaces and/or subretinal fluid on OCT. RESULTS: Twenty-five eyes of 25 patients were enrolled. Twenty-two eyes had similar results on both OCT and FFA, of which 15 eyes had CME and 7 eyes had no CME. Two eyes had CME detected only by FFA and one eye only by OCT. The agreement between the two examinations was good (Kappa = 0.7331; p=0.0001 with no tendency to have neither more positive nor negative findings (p=1.0. CONCLUSION: According to these preliminary data, OCT seems to be as effective as FFA to detect CME with a good agreement between the two techniques.

  1. Acoso escolar en la zona metropolitana de Guadalajara, México: prevalencia y factores asociados

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    María Guadalupe Vega López

    2013-01-01

    Full Text Available Este estudio tiene como objetivos determinar la prevalencia de víctimas de acoso escolar en alumnos de escuelas secundarias públicas de la zona metropolitana de Guadalajara, México, e identificar factores asociados al hecho de ser víctima en el pe- ríodo 2009-2011. Se realizó un estudio de tipo transversal analítico. Se diseñó una mues- tra probabilística polietápica de escuelas secundarias públicas y se estudiaron 1.706 alumnos entre 11 y 16 años. Se aplicó un instrumento con cuatro apartados que permitió identificar a las víctimas de acoso y se utilizó un modelo de regresión logística para me- dir la asociación entre los factores analizados y el ser víctima de acoso. La prevalencia de acoso escolar fue del 17,6% (IC95% 15,8; 19,5. Factores de carácter personal, como sentir que no es aceptado por el grupo o no pasar mucho tiempo con amigos, fueron los que tuvieron una asociación más fuerte y estadísticamente significativa con el hecho de ser víctima de acoso en la escuela.

  2. Factores asociados al desarrollo de preeclampsia en un hospital de Piura, Perú

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    Yamalí Benites-Condor

    2012-09-01

    Full Text Available Introducción: La Organización Mundial de la Salud indica que diariamente fallecen alrededor de 800 mujeres por causas relacionadas al embarazo y parto, dentro de las cuales la preeclampsia ocupa el tercer lugar. Objetivo: identificar los factores asociados a preeclampsia en gestantes que fueron hospitalizadas en el Hospital de Apoyo II “Santa Rosa” de la ciudad de Piura durante el periodo junio 2010 - mayo 2011. Métodos: Se realizó un estudio descriptivo retrospectivo de casos y controles, en gestantes hospitalizadas entre junio del 2010 y mayo del 2011. Mediante un muestreo aleatorio se obtuvieron 39 casos de preeclampsia y 78 controles sin preeclampsia. Los datos fueron analizados con el paquete estadístico SPSS v19.0, en el cual se ejecutó un análisis de casos y controles no pareados aplicando la prueba Chi cuadrado. Resultados: Fueron variables significativamente asociadas con la preeclampsia: Edad 35 años  (p=0,021, y número de controles prenatales mayor o igual a siete (p= 0,049. No resultaron significativos la primiparidad ni el sobrepeso. Interpretación: Se debe promover un control prenatal adecuado (traducido como siete o más controles durante la gestación, especialmente en aquellas mujeres que se encuentran en los extremos de la vida fértil.

  3. FACTORES ASOCIADOS AL DESARROLLO DE PREECLAMPSIA EN UN HOSPITAL DE PIURA, PERÚ

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    Yamalí Benites-Cóndor

    2011-01-01

    Full Text Available Introducción: La Organización Mundial de la Salud indica que diariamente fallecen alrededor de 800 mujeres por causas relacionadas al embarazo y parto, dentro de las cuales la preeclampsia ocupa el tercer lugar. Objetivo: identificar los factores asociados a preeclampsia en gestantes que fueron hospitalizadas en el Hospital de Apoyo II "Santa Rosa" de la ciudad de Piura durante el periodo junio 2010 - mayo 2011. Métodos: Se realizó un estudio descriptivo retrospectivo de casos y controles, en gestantes hospitalizadas entre junio del 2010 y mayo del 2011. Mediante un muestreo aleatorio se obtuvieron 39 casos de preeclampsia y 78 controles sin preeclampsia. Los datos fueron analizados con el paquete estadístico SPSS v19.0, en el cual se ejecutó un análisis de casos y controles no pareados aplicando la prueba Chi cuadrado. Resultados: Fueron variables significativamente asociadas con la preeclampsia: Edad 35 años (p=0,021, y número de controles prenatales mayor o igual a siete (p= 0,049. No resultaron significativos la primiparidad ni el sobrepeso. Interpretación: Se debe promover un control prenatal adecuado (traducido como siete o más controles durante la gestación, especialmente en aquellas mujeres que se encuentran en los extremos de la vida fértil.

  4. Factores asociados con la compacidad final de los concretos asfálticos

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    Jorge Tamayo T.

    1982-09-01

    Full Text Available Se reconoce universalmente el alto grado de dependencia de las propiedades fundamentales que exhiben las capas de concreto asfáltico con su nivel de compacidad, por lo cual resulta importante estudiar los aspectos principales asociados con la optimización de esta característica. Resulta particularmente importante conocer las propiedades de los agregados en cuanto a su naturaleza, distribución granulométrica, tipo de llenante, forma de las partículas, así como las del asfalto en función de su comportamiento reológico y las relaciones entre estos ingredientes. En razón de la naturaleza termoplástica de las mezclas asfálticas, el control de la temperatura y la evolución de la misma por medio de las diversas fases del proceso, resulta determinante en la compacidad final. Otros factores igualmente incidentes son: la programación racional de las actividades, los equipos empleados y la secuencia de la compactación. Este documento pretende presentar algunas ideas sobre estos aspectos que permiten mejorar las prácticas constructivas existentes con miras a optimizar el comportamiento de los pavimentos flexibles.

  5. Motivos asociados a la conducta violenta contra la pareja en hombres desmovilizados del conflicto armado

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    José Hernando Ávila-Toscano

    2011-01-01

    Full Text Available El objetivo del estudio fue identificar motivos asociados a las conductas violentas contra la pareja en las relaciones conyugales de desmovilizados del conflicto armado colombiano. Se evaluaron 224 hombres residentes en una zona de distensión militar y reacomodación psicosocial en la Costa Caribe colombiana mediante un diseño correlacional, aplicando dos cuestionarios para la detección de conductas violentas y los motivos relacionados con las mismas. Los datos se analizaron con Chi Cuadrado (x2 y análisis de regresión logística múltiple por pasos. El promedio de violencia conyugal fue de 82.1%, sobresaliendo las agresiones verbales, abandono o descuido, amenazas y coacción. Los antecedentes de relaciones conyugales previas y de maltrato en las mismas se asociaron a los episodios actuales de violencia (p<0.05. Motivos como sensación de malestar, historia de maltrato en la familia de origen, imposición, rabia, entre otros, se asociaron a las formas de agresión conyugal..

  6. Primer registro de Naupactus ruizi (Coleoptera: Curculionoidea asociado con Pinus ponderosa (Gymnospermae: Pinaceae en Patagonia

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    Cecilia A. GOMEZ

    2006-01-01

    Full Text Available Naupactus ruizi (Brèthes es un gorgojo de rostro corto, distribuido en la Argentina y Chile, que habita en ambientes áridos asociado con vegetación xerofítica y alcanza el rango más austral entre los miembros de la tribu Naupactini. Un relevamiento de insectos y de patógenos como plagas potenciales, realizado durante el 2005 en plantaciones de Pinus spp. en la Patagonia andina argentina, resultó en el hallazgo de adultos de N. ruizi que se alimentaban de acículas de Pinus ponderosa Dougl. ex Laws. Este hallazgo es sorprendente dado que las especies de Naupactini, consumen casi exclusivamente angiospermas. Interpretamos que el cambio de huésped, habría ocurrido como consecuencia de una colonización reciente favorecida por la amplia distribución geográfica del gorgojo y su capacidad para sobrevivir en hábitats marginales, donde probablemente las plantas nativas son escasas y el nuevo huésped presenta una gran abundancia local.

  7. MOTIVOS ASOCIADOS A LA CONDUCTA VIOLENTA CONTRA LA PAREJA EN HOMBRES DESMOVILIZADOS DEL CONFLICTO ARMADO

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    José Hernando Ávila-Toscano

    2010-05-01

    Full Text Available El objetivo del estudio fue identificar motivos asociados a las conductas violentas contra la pareja en las relaciones conyugales de desmovilizados del conflicto armado colombiano. Se evaluaron 224 hombres residentes en una zona de distensión militar y reacomodación psicosocial en la Costa Caribe colombiana mediante un diseño correlacional, aplicando dos cuestionarios para la detección de conductas violentas y los motivos relacionados con las mismas. Los datos se analizaron con Chi Cuadrado (x2 y análisis de regresión logística múltiple por pasos. El promedio de violencia conyugal fue de 82.1%, sobresaliendo las agresiones verbales, abandono o descuido, amenazas y coacción. Los antecedentes de relaciones conyugales previas y de maltrato en las mismas se asociaron a los episodios actuales de violencia (p<0.05. Motivos como sensación de malestar, historia de maltrato en la familia de origen, imposición, rabia, entre otros, se asociaron a las formas de agresión conyugal..

  8. Agentes protectores contra hongos asociados a la semilla de pejibaye (bactris gasipaes kunth

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    Carlos Arroyo

    2000-01-01

    Full Text Available Agentes protectores contra hongos asociados a la semilla de pejibaye (Bactris gasipaes Kunth. Se presenta un estudio de alternativas no tradicionales, para el control del ataque fungoso a las semillas de pejibaye durante el proceso de germinación. Se evaluó el efecto de 13 agentes protectores: Vitavax + Benomil, Bayletón, NaCl, Cloro, Kilol, Alcohol, H2O2, Aserrín, H2O, Gasolina, Diesel, Kerosene y Chile picante. De las sustancias probadas, la inmersión en kerosene y gasolina, mostraron un comportamiento tan efectivo como los fungicidas triadimefom (Bayletón y la mezcla de carboxin + benomyl. Esto debido al efecto fungicida y su posterior evaporación, no interfiriendo con la respiración, como fue el caso del aceite diesel. Se encontró además que el peróxido de hidrógeno (H2O2, tuvo un efecto acelerador de la germinación, pero no actuó como buen fungicida. El kilol, mostró un efecto fungicida prometedor a concentración superior a los 10 cc/l de agua

  9. TAMBEROS DE LA CUENCA LECHERA CENTRAL SANTAFESINA. ¿PRODUCTOR ASOCIADO O MANO DE OBRA?

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    P. S. M. SANDOVAL

    2017-12-01

    Full Text Available El proceso de modernización del agro de las dos últimas décadas, incide directamente en un sujeto social de la cuenca lechera santafesina. 1990 genera nueva legislación que enmarca el trabajo y la vida del tambero y su familia, reconfi gurando este sujeto social fundamental. La metodología cualitativa utilizada fue Estudio de Caso sobre el Departamento las Colonias. Los resultados presentados en este artículo demuestran que los cambios ocurridos por la nueva fi gura legal del tambero, impactan en sus condiciones de vida. A pesar que la nueva legislación convierte al empleado tambero en productor asociado, no provoca mejoras en su situación socioeconómica. El trabajo completo es un proceso de articulación entre actividad científi ca y desarrollo rural, donde se identificaron y sistematizaron los contextos de ambas situaciones legales y los cambios en las condiciones de vida del tambero y su familia, suministrando conocimientos para orientar la tarea de extensión relacionada al desarrollo rural.

  10. Factores asociados a la utilización de servicios de salud odontológicos

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    María Silvina Dho

    Full Text Available Resumen El presente trabajo se propone analizar los factores asociados a la utilización de servicios de salud odontológicos (USSO en individuos adultos de la Ciudad de Corrientes; Argentina. Se realizó un estudio transversal. A través de una encuesta domiciliaria se recolectó información de las variables de estudio. Se determinó el tamaño de la muestra estableciéndose un nivel de confianza del 95% (381 individuos. Se aplicó un diseño muestral aleatorio simple, que se complementó con un muestreo no probabilístico por cuotas. Se analizaron los datos con los programas SPSS 21.0. y Epidat 3.1. El nivel socioeconómico, la cobertura social odontológica, la percepción sobre la salud bucal, los conocimientos de salud bucal y los hábitos de higiene bucal se asociaron significativamente a la USSO en los últimos 12 meses. Los mismos factores, a excepción de la cobertura social odontológica y de los conocimientos de salud bucal, se asocian a la USSO por motivos de control/chequeo dental de rutina. Se deben implementar medidas tendientes a aumentar la USSO con fines de prevención en individuos de ambos sexos, de todos los niveles socioeconómicos, especialmente en aquellos menos favorecidos.

  11. Factores asociados y consecuencias clínicas de la anemia post trasplante renal

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    Mónica Freiberg

    2013-04-01

    Full Text Available Un porcentaje considerable de pacientes presentan anemia post trasplante renal. Su origen es multifactorial y sus principales etiologías dependen de la etapa post trasplante que se considere. Estudiamos en un grupo de 134 pacientes los factores asociados con anemia tardía (6 meses post trasplante y sus implicaciones clínicas a mediano plazo. En el análisis de regresión múltiple, la duración de la oliguria post trasplante y el número de episodios de rechazo fueron las variables significativamente asociadas con esta complicación. La supervivencia del órgano mostró una diferencia significativa a los 36 meses entre los grupos (83% en los anémicos versus 96% de los no anémicos p < 0.01. No observamos diferencias en mortalidad o eventos cardiovasculares. Concluimos que la presencia de anemia al sexto mes post trasplante renal está independiente y significativamente asociada con factores que condicionan la masa renal funcionante que explicarían además la menor supervivencia del injerto renal observada en estos pacientes.

  12. UTILIZATION OF FUNDUS AUTOFLUORESCENCE, SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHY, AND ENHANCED DEPTH IMAGING IN THE CHARACTERIZATION OF BIETTI CRYSTALLINE DYSTROPHY IN DIFFERENT STAGES.

    Science.gov (United States)

    Li, Qian; Li, Yang; Zhang, Xiaohui; Xu, Zhangxing; Zhu, Xiaoqing; Ma, Kai; She, Haicheng; Peng, Xiaoyan

    2015-10-01

    To characterize Bietti crystalline dystrophy (BCD) in different stages using multiple imaging modalities. Sixteen participants clinically diagnosed as BCD were included in the retrospective study and were categorized into 3 stages according to fundus photography. Eleven patients were genetically confirmed. Fundus autofluorescence, spectral domain optical coherence tomography, and enhanced depth imaging features of BCD were analyzed. On fundus autofluorescence, the abnormal autofluorescence was shown to enlarge in area and decrease in intensity with stages. Using spectral domain optical coherence tomography, the abnormalities in Stage 1 were observed to localize in outer retinal layers, whereas in Stage 2 and Stage 3, more extensive retinal atrophy was seen. In enhanced depth imaging, the subfoveal choroidal layers were delineated clearly in Stage 1; in Stage 2, destructions were primarily found in the choriocapillaris with associated alterations in the outer vessels; Stage 3 BCD displayed severe choroidal thinning. Choroidal neovascularization and macular edema were exhibited with high incidence. IVS6-8del17bp/inGC of the CYP4V2 gene was the most common mutant allele. Noninvasive fundus autofluorescence, spectral domain optical coherence tomography, and enhanced depth imaging may help to characterize the chorioretinal pathology of BCD at different degrees, and therefore, we propose staging of BCD depending on those methods. Physicians should be cautious of the vision-threatening complications of the disease.

  13. Harvesting the weak angular reflections from the fundus of the human eye : on measuring and analyzing the light wasted by the retina

    NARCIS (Netherlands)

    Kraats, J. van der

    2007-01-01

    Summary of the thesis “Harvesting the weak angular reflections from the fundus of the human eye” by Jan van de Kraats University Medical Centre Utrecht. Defended October 16, 2007. This thesis is on the modeling of the optical reflection of the human fovea, and on the three instruments build for

  14. Automated Detection and Differentiation of Drusen, Exudates, and Cotton-Wool Spots in Digital Color Fundus Photographs for Diabetic Retinopathy Diagnosis

    NARCIS (Netherlands)

    Niemeijer, M.; van Ginneken, B.; Russel, S.R.; Suttorp-Schulten, M.S.A.; Abràmoff, M.D.

    2007-01-01

    purpose. To describe and evaluate a machine learning-based, automated system to detect exudates and cotton-wool spots in digital color fundus photographs and differentiate them from drusen, for early diagnosis of diabetic retinopathy. methods. Three hundred retinal images from one eye of 300

  15. Prevalencia y factores de riesgo asociados a sífilis en mujeres

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    Carlos A. Hernández-Girón

    1998-12-01

    Full Text Available INTRODUCCIÓN: Se ha demostrado que la sífilis, debido a la ulceración genital que produce, es un cofactor asociado para adquirir otras enfermedades de transmisión sexual (ETS, principalmente de origen viral como herpes tipo-2, hepatitis B, y el VIH. Aunque las mujeres trabajadoras del sexo comercial (MTSC han adquirido mejores conocimientos para prevenir las ETS, constituyen un grupo que por su heterogenicidad en términos de condición socioeconómica, estado de salud, ambiente y sitio de trabajo, manifiestan diferentes actitudes y conocimientos que hacen latente la posibilidad de adquirir y transmitir ETS incluyendo sífilis, por lo que lo estudio hace un acercamiento hacia los factores asociados a infección por Treponema pallidum en este grupo de mujeres. MÉTODO: Basado en un marco muestral, que identifica sitios donde se practica el comercio sexual femenino en la ciudad de México, se seleccionó una muestra de 807 MTSC, a quienes previo consentimiento informado, se entrevistó para que respondieran un cuestionario estructurado. Se obtuvo una muestra sanguínea para la identificación de diversos marcadores serológicos de ETS de acuerdo al manual de procedimientos para el diagnóstico de ETS. Para el diagnóstico de Treponema pallidum se utilizó una prueba de tamizaje de RPR (Bigaux Diagnóstica, y prueba confirmatoria de FTA-ABS (Pasteur Diagnostics. RESULTADOS: Las prevalencias de sífilis en la muestra de MTSC fue de 6,4% (52/807, siendo mayor en quienes trabajaban en sitios de calle comparadas con aquellas de estéticas. La edad de las mujeres entrevistadas osciló entre 17 y 58 años con una media de 29,2 años (d.s. 7,3 años. La prevalencia de sífilis fue mayor en los grupos etáreos mayores de 30 anos. La edad de inicio de relaciones sexuales varió desde 11 hasta 30 anos con una media de 16 años (d.s. 3,1 años. Los factores predictores de infección por T. pallidum, determinados mediante regresión logística ajustada

  16. Prevalencia y factores de riesgo asociados a sífilis en mujeres

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    Hernández-Girón Carlos A.

    1998-01-01

    Full Text Available INTRODUCCIÓN: Se ha demostrado que la sífilis, debido a la ulceración genital que produce, es un cofactor asociado para adquirir otras enfermedades de transmisión sexual (ETS, principalmente de origen viral como herpes tipo-2, hepatitis B, y el VIH. Aunque las mujeres trabajadoras del sexo comercial (MTSC han adquirido mejores conocimientos para prevenir las ETS, constituyen un grupo que por su heterogenicidad en términos de condición socioeconómica, estado de salud, ambiente y sitio de trabajo, manifiestan diferentes actitudes y conocimientos que hacen latente la posibilidad de adquirir y transmitir ETS incluyendo sífilis, por lo que lo estudio hace un acercamiento hacia los factores asociados a infección por Treponema pallidum en este grupo de mujeres. MÉTODO: Basado en un marco muestral, que identifica sitios donde se practica el comercio sexual femenino en la ciudad de México, se seleccionó una muestra de 807 MTSC, a quienes previo consentimiento informado, se entrevistó para que respondieran un cuestionario estructurado. Se obtuvo una muestra sanguínea para la identificación de diversos marcadores serológicos de ETS de acuerdo al manual de procedimientos para el diagnóstico de ETS. Para el diagnóstico de Treponema pallidum se utilizó una prueba de tamizaje de RPR (Bigaux Diagnóstica, y prueba confirmatoria de FTA-ABS (Pasteur Diagnostics. RESULTADOS: Las prevalencias de sífilis en la muestra de MTSC fue de 6,4% (52/807, siendo mayor en quienes trabajaban en sitios de calle comparadas con aquellas de estéticas. La edad de las mujeres entrevistadas osciló entre 17 y 58 años con una media de 29,2 años (d.s. 7,3 años. La prevalencia de sífilis fue mayor en los grupos etáreos mayores de 30 anos. La edad de inicio de relaciones sexuales varió desde 11 hasta 30 anos con una media de 16 años (d.s. 3,1 años. Los factores predictores de infección por T. pallidum, determinados mediante regresión logística ajustada

  17. Síndrome de Sweet asociado a neoplasias Sweet's syndrome associated with neoplasms

    Directory of Open Access Journals (Sweden)

    Mariana Franco

    2006-10-01

    Full Text Available El síndrome de Sweet fue descrito en el año 1964 por Robert Douglas Sweet, como una entidad a la cual denominó dermatosis neutrofílica febril y aguda. Se caracteriza por cinco rasgos principales: 1 aparición brusca de placas eritemato-dolorosas en cara, cuello y extremidades; 2 fiebre; 3 leucocitosis polimorfonuclear; 4 denso infiltrado dérmico a predominio neutrofilico; 5 rápida respuesta al tratamiento esteroideo. Se puede clasificar en cinco grupos: idiopático, parainflamatorio, paraneoplásico, secundario a drogas y asociado a embarazo. En el 20% de los casos se asocia a enfermedades malignas, representando las hematológicas el 85% y los tumores sólidos el 15% restante. Se presenta una serie de siete casos de síndrome de Sweet asociado a neoplasias, diagnosticados durante el período 2002-2006, de los cuales seis correspondieron a enfermedades oncohematológicas y el restante a tumores sólidos. Como comentario de dicha casuística, se hace hincapié en la importancia del diagnóstico de este síndrome, debido a que puede anunciar la recaída del tumor o la progresión de la enfermedad de base. De esta manera, mediante el uso de métodos de diagnóstico y tratamiento oportunos, se lograría mejorar la calida de vida de estos pacientes. También debe tenerse en cuenta, que los pacientes oncológicos reciben múltiples medicaciones (factor estimulante de colonias, que pueden estar implicadas en la aparición de esta entidad, debiendo ser las mismas descartadas como posibles causas.Sweet's syndrome was described in 1964 by Robert Douglas Sweet, as an entity he named acute febrile neutrophilic dermatosis. It is characterized by five main features: 1 sudden appearance of erythematous and tender plaques on the face, neck and extremities; 2 fever; 3 polymorphonuclear leukocytes; 4 predominantly neutrophilic dense infiltrate in the dermis, and 5 rapid response to steroid therapy. Sweet's syndrome can be classified into five groups

  18. Lactancia materna ineficaz: prevalencia y factores asociados Ineffective Breastfeeding: prevalence and associated factors

    Directory of Open Access Journals (Sweden)

    Elvinia Pinilla Gómez

    2011-12-01

    Full Text Available Introducción: Es posible evitar muertes neonatales mediante la lactancia materna desde el primer día de vida, pues la leche materna es el alimento óptimo para el lactante por su contenido nutricional necesario favorecer el crecimiento y desarrollo. Objetivo: Determinar la prevalencia y factores asociados al diagnóstico de enfermería "Lactancia materna ineficaz" en lactantes menores de 6 meses hospitalizados en una institución de tercer nivel. Metodología: Estudio de corte transversal. Se seleccionaron 108 binomios (madre e hijo hospitalizados en una institución de tercer nivel de atención en el año 2009, se aplicó un formato validado para identificar el diagnóstico. Se realizó análisis Rasch a las variables que representan las características definitorias del diagnóstico, con el cual se creó una escala de 0 a 100 y se construyó un modelo de regresión lineal con las variables asociadas a la medida del diagnóstico. Resultados: la prevalencia del diagnóstico fue de 93,5 %, la característica definitoria más fácil de encontrar fue Incapacidad del lactante para agarrarse al pecho materno y la más difícil fue agitación y llanto del lactante dentro de la primera hora después de la lactancia materna. La regresión lineal mostró factores asociados como: género femenino, peso del lactante y necesidad de la madre de ir a orinar. Conclusión: Existe una tendencia desfavorable tanto en la prevalencia como en la duración de la lactancia materna para los lactantes hospitalizados; la promoción de la lactancia materna debe ser un trabajo interdisciplinario; modificar las normas hospitalarias favoreciendo el contacto del binomio y la puesta temprana al pecho materno. Salud UIS 2011; 43 (3: 271-279Introduction: neonatal deaths can be prevented by breastfeeding from the first day of life, as is the optimal food for infants by their nutritional content required for better growth and development. Objective: To determine the prevalence

  19. Análisis de los factores asociados a la calidad de vida del paciente hipertenso

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    Cristina Nolasco Monterroso

    2015-12-01

    Full Text Available Introducción: En la Hipertensión Arterial (HTA existen una serie de factores asociados a la misma que inciden en la Calidad de Vida Relacionada con la Salud (CVRS de la población en general, como es el caso de la Diabetes Mellitus, el hábito tabáquico, alimentación, etc. Objetivo: Analizar la CVRS y los factores asociados a ésta, en pacientes con HTA controlados en la Unidad de Hipertensión de la Unidad de Gestión Clínica (UGC Nefrología del Hospital Universitario Reina Sofía (HURS de Córdoba. Pacientes y Métodos: Se ha realizado un estudio observacional, descriptivo y transversal, en 33 pacientes hipertensos con una edad media de 73,24±5,55 años; 20 hombres (60,6% y 13 mujeres (39,4% controlados en la Unida de Hipertensión de la UGC Nefrología del HURS de Córdoba. Se analizó la CVRS mediante el cuestionario de salud SF-36. Para el análisis de la dependencia se utilizó el Índice de Barthel. Resultados: Los valores de la CVRS fueron: Salud General 43.36±24.84, Función Física 58.18±32.71, Rol Físico 78.98±34.51, Rol Emocional 82.07±28.50, Función Social 81.81±33.67, Dolor Corporal 66.06±39.42, Vitalidad 63.83±33,80, Salud Mental 70.45±29.27. La Función Física, Salud General y Dolor Corporal fueron las dimensiones en las que puntuaron más bajo que la población de referencia. Respecto al grado de dependencia, el 45.45% eran independientes el 51.51% presentaban dependencia leve, y el 3.03% presentaban una dependencia grave. Se encontró una correlación estadísticamente significativa entre edad y la dimensión Función Física y Vitalidad; entre peso y Rol Físico y el Índice de Masa Corporal (IMC; entre ejercicio y Función Social; entre el IMC y Rol Físico y Componente Salud Física. Los pacientes con algún grado de dependencia tenían disminuida la CVRS en comparación con los independientes. Conclusiones: A la vista de nuestros resultados podemos afirmar que, al menos en la muestra estudiada, la

  20. Mecanismos de desgaste en refractarios de colada continua asociados al efecto Marangoni

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    Brandaleze, E.

    2005-12-01

    Full Text Available Nozzle wear during continuous casting process is caused by physical and chemical reasons and also by refractory quality. A post mortem study on a sample of Al2O3 - graphite nozzle with a ZrO2 insert allows to identify the present wear mechanisms. Different cyclic stages are carried out due to recurrent changes of interfacial tension and fluid convection. When the surface tension promote the refractory wetting by the steel, graphite of the nozzle surface is lost. Then, grains of ZrO2 and of Al2O3 are dissolved by slag contact. This type of wear is associated with the Marangoni effect. Light and electronic microscopy was used to observe the refractory structure and by a cathodoluminiscence technique phases transformations under process conditions are determined.

    Las buzas sumergidas se erosionan durante el proceso de la colada continua, debido a causas físicas, químicas y a la calidad del refractario. El estudio post mortem de una buza de Al2O3 -grafito con inserto de ZrO2 permite identificar los mecanismos de desgaste presentes, que ocurren por etapas debido a cambios cíclicos de tensión interfacial y convección de fluidos. Cuando la tensión superficial favorece la mojabilidad del refractario por el acero, la buza pierde grafito de la superficie. Luego, los granos de ZrO2 y de Al2O3 se disuelven al ser mojados por la escoria. Este desgaste está asociado al efecto Marangoni. Se observa la microestructura mediante microscopía óptica y electrónica y, por catodoluminiscencia, se determinan las transformaciones de fases ocurridas en condiciones de proceso.

  1. Incidencia y factores asociados con las reacciones adversas del tratamiento antirretroviral inicial en pacientes con VIH

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    Juan Astuvilca

    2007-07-01

    Full Text Available La alta incidencia de reacciones adversas medicamentosas (RAMA al tratamiento antirretroviral de gran actividad (TARGA en pacientes con VIH/SIDA puede afectar la calidad de vida y adherencia al tratamiento. Objetivos: Determinar la incidencia de RAMA del TARGA inicial e identificar los factores asociados con la ocurrencia de RAMA al recibir dicha terapia. Materiales y métodos: Se realizó un estudio de cohorte histórica con todos los pacientes VIH (+ mayores de 18 años que recibieron TARGA por primera vez en el Hospital Nacional Arzobispo Loayza, con un seguimiento de 360 días desde la primera prescripción. Se recabó las RAMA de las historias clínicas y tarjetas de control. Resultados: Se incluyeron 353 pacientes, se encontró una incidencia acumulada de 66,7% de efectos adversos al TARGA inicial y una densidad de incidencia de 9,1 eventos de RAMA por 10 personas año de seguimiento (IC95%: 8,1-10,1. Anemia (23,4%, náuseas (20,6% y rash (17,2% fueron las RAMA más frecuentes. El uso de drogas (OR 2,40; IC95% 1,01-5,67; consumo de alcohol (OR 0.32; IC95%: 0,19-0,55 y estadio SIDA (OR 0,20; IC95%: 0,04-0,95 estuvieron asociadas con la presencia de RAMA. Conclusiones: Existe un alta incidencia de RAMA, siendo la anemia la más frecuente. El uso de drogas es un factor de riesgo para presentar RAMA.

  2. Apendicitis aguda en el paciente senil: Factores asociados a una mayor morbimortalidad post operatoria

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    Víctor Eduardo Chian Chang

    1996-04-01

    Full Text Available Objetivo: Definir los factores asociados a una mayor morbilidad y mortalidad en pacientes seniles con apendicitis aguda. Material y métodos: Se realizó un estudio retrospectivo con 100 pacientes intervenidos en el Hospital Nacional Arzobispo Loayza, durante el período comprendido entre 1984 a 1994. Resultados: Se asociaron a una mayor frecuencia de complicaciones postoperatorias: edad mayor o igual a 70 años, tiempo de enfermedad mayor de 48 horas, presencia de apendicitis perforada con peritonitis localizada o generalizada (p<0.05. Además la presencia de apendicitis perforada se asoció significativamente a la presencia de absceso residual y/o fístula estercorácea (p=0.027 y la presencia de AA gangrenosa o perforada a mayor frecuencia de infección de herida operatoria (p<0.05. El antecedente de patología cardiovascular previa se asoció a mayor frecuencia de complicaciones cardiovasculares (p<0.05. Se asociaron a mayor mortalidad en AA, pacientes con intervención quirúrgica adicional a la apendicetomía (p=0.016 y presencia de AA perforada (p=0.027. Conclusiones: Los estadios avanzados de AA, así como la presencia de problema cardiovascular al momento del diagnóstico se asociaron con una mayor frecuencia de complicaciones post-operatorias. La presencia de peritonitis se asocia con la mortalidad. (Rev Med Hered 1996; 7: 62-67.

  3. Infecciones respiratorias agudas y factores asociados Acute respiratory infections and associated factors

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    Rogelio León López

    2005-12-01

    Full Text Available Se realizó un estudio descriptivo y retrospectivo con la finalidad de conocer la relación entre las infecciones respiratorias agudas con algunos factores asociados seleccionados en lactantes, durante el trienio 2001-2003, en el área de salud del Policlínico Docente “30 de Noviembre”, del municipio 10 de Octubre. La incidencia de estas enfermedades en el mencionado período fue de 933 x 1 000. Se encontró que la mayoría de los infantes exhibió un adecuado estado inmunológico y nutricional, así como también que no tenían historia de alergia respiratoria. La institucionalización de estos niños no influyó en la aparición de estas enfermedades, y el tratamiento que predominó fue el sintomático.A descriptive and retrospective study was conducted to know the relation between acute respiratory infections and some associated factors selected in infants from the health area of “30 de Noviembre” Teaching Polyclinic, in “10 de Octubre” municipality, between 2001 and 2003. The incidence of these diseases in the above period was 933 x 1000. It was observed that most of the infants had an adequate immunological and nutritional state, and that they did not have any history of respiratory allergy. The institutionalization of these children did not influence on the appearance of these diseases. There was a predominance of the symptomatic treatment.

  4. Caracterización de algunos factores de riesgo asociados al intento suicida en adolescentes

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    Idelis Fedeslinda Arias de la Torre

    2015-03-01

    Full Text Available El intento suicida es un problema de salud frecuente en los adolescentes, su manejo en muchas ocasiones resulta complejo y desalentador, por el riesgo de suicidio. Se realizó un estudio observacional, descriptivo, retrospectivo, con el objetivo de caracterizar algunos de los factores de riesgo asociados al intento suicida en los adolescentes del municipio de Bayamo en el año 2014. La población de estudio estuvo conformada por los 108 adolescentes que presentaron intento suicida, notificados por tarjeta de enfermedad de declaración obligatoria (EDO, en el departamento de Estadística de dicho municipio, en el período de estudio. Se estudiaron las variables edad, sexo, área de salud, antecedentes patológicos personales de enfermedades o sintomatologías psiquiátricas, conflictos personales, conflictos familiares y el método empleado de suicidio. Los datos fueron analizados mediante el paquete estadístico SPSS, mostrados en tablas, expresados en números y porcientos. En la población de estudio predominó el sexo femenino (78,70 %, el grupo de edad de 14 a 16 años (50 %, el área de salud del policlínico Bayamo Oeste (tasa 74,9 x 10 000 habitantes, los deseos de hacerse daño (100 %, las malas relaciones con los padres (63,9 % y la ingestión de tabletas (92,7 %

  5. Factores asociados al inicio de la lactancia materna en mujeres dominicanas

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    Leonelo E. Bautista

    1997-03-01

    Full Text Available Las relaciones entre el inicio del amamantamiento y sus determinantes varían en distintas poblaciones, pero su conocimiento es fundamental para orientar los programas de promoción de la lactancia materna. Los datos de la Encuesta Demográfica y de Salud de 1991 de la República Dominicana se usaron para identificar factores asociados con el inicio del amamantamiento en una muestra aleatoria de mujeres en edad fértil. Aproximadamente 93% de 2714 madres informaron haber iniciado el amamantamiento en su último niño nacido vivo menor de 5 años y no hubo cambios importantes en este porcentaje en los últimos 5 años. Se realizó un análisis de regresión logística mediante el cual se calcularon valores de la razón de posibilidades (u odds ratio (psi, en inglés como medidas de asociación. Las madres que tuvieron alguna enfermedad durante el embarazo (psi = 2,3, las que tuvieron niños con bajo peso al nacer (psi= 2,9, las primíparas (psi = 1,9 y las de nivel de ingresos medio (psi = 1,6 y alto (psi = 2,1 tuvieron un riesgo significativamente mayor de no iniciar el amamantamiento. Estas mujeres deberían constituir grupos prioritarios en los programas de promoción de la lactancia materna.

  6. Factores asociados a cáncer de pulmón en mujeres

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    Mayra A Farias

    2008-07-01

    Full Text Available Aunque el cáncer de mama es la enfermedad maligna más común diagnosticada en mujeres, es el cáncer de pulmón el que presenta mayor mortalidad. Fumar es una de las causas directas de este cáncer. Hay también diferencias en términos de sobrevida donde las mujeres tienden a mostrar mejor índice después de una resección quirúrgica en estadíos tempranos o también cuando presentan metástasis. Las variaciones genéticas entre hombres y mujeres y su posible rol en la oncogénesis tienden a ser evidentes, incluyendo aquellos genes como el CYP1A1 o el receptor del péptido liberador de gastrina. El posible rol de los estrógenos ha sido mostrado en estudios de caso control donde factores como la menopausia temprana, uso de tabaco, estrógenos y terapia de reemplazo hormonal son asociados como factores de riesgo. De manera interesante, las mujeres jóvenes con cáncer de pulmón tienen mejor respuesta a los inhibidores de la Tirosina kinasa (TKIs como gefinitib y erlotinib. La identificación de mutaciones en el dominio de unión del ATP del receptor del factor de crecimiento epidermal podrían predecir respuestas dramáticas e introducir la posibilidad de una terapia más individualizada. (Rev Med Hered 2008;19:108-116

  7. Factores de riesgo asociados a infecciones en pacientes hospitalizados en la Unidad de Cuidados Intensivos (UCI

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    Ruby Elizabeth Vargas-Toloza

    2010-12-01

    Full Text Available Este estudio de abordaje Cuantitativo Descriptivo Transversal busca determinar los factores de riesgos intrínsecos y extrínsecos, medios diagnósticos e incidencia; asociados a Infecciones en los pacientes hospitalizados en la Unidad de Cuidados Intensivos (UCI de la Clínica San José en la ciudad de Cúcuta. La Edad, es un factor predisponente en el desarrollo de infecciones en los pacientes que ingresaron a la Unidad de Cuidados Intensivos (UCI de la Clínica San José durante el periodo evaluado, se observó que la infección fue más frecuente en los adultos mayores de 41 años con un 86.5%. Las enfermedades de base relacionadas con la aparición de infecciones (Diabetes, Enfermedad Pulmonar Obstructiva Crónica (EPOC, Hepatopatía e Insuficiencia Renal, en el estudio no evidenció un comportamiento estadísticamente significativo, sin embargo, el 34.3% de los pacientes que presentaron insuficiencia renal, seguido del 29.9% que presentaron Enfermedad Pulmonar Obstructiva Crónica (EPOC y Diabetes, tienen un mayor riesgo de desarrollar infecciones que los pacientes que carecen de este antecedente durante su tiempo de hospitalización en la Unidad de Cuidados Intensivos (UCI, siendo este un factor de riesgo predisponente en la aparición de las infecciones. Dentro de los procedimientos invasivos más usados están la sonda urinaria, la ventilación mecánica y el catéter venoso central. La incidencia de infección en la población objeto del presente estudio fue de 17,9%. Los agentes infecciosos que estuvieron presentes tanto en sangre, como en orina y secreción bronquial fueron Escherichia coli, Klebsiella y Staphylococcus Aureus, microorganismos altamente contagiosos y perjudiciales.

  8. Factores de riesgo asociados a osteopenia del prematuro en una terapia intensiva neonatal de referencia

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    MP Ríos-Moreno

    2016-03-01

    Full Text Available INTRODUCCIÓN: la enfermedad ósea metabólica del prematuro resulta de la desmineralización ósea. Existen factores que deben vigilarse con la finalidad de realizar diagnóstico y tratamiento temprano. OBJETIVO: determinar los factores de riesgo asociados a osteopenia en prematuros. MATERIALES Y MÉTODOS: estudio transversal comparativo de octubre del 2011 a octubre del 2013. Se incluyeron 120 prematuros 900 UI/L. Factores de riesgo determinados con razón de momios (OR. Estadística inferencial con c2 y t de Student. RESULTADOS: se diagnosticó enfermedad ósea metabólica en 58 prematuros (48%, peso 1067 ± 216 gramos, edad gestacional 28 ± 1.6 semanas, edad postnatal 41 ± 15.5 días. Género masculino 32 (55%. Factores de riesgo: peso < 1,000 gramos OR 4.64, (2.13-10.10, displasia broncopulmonar moderada o severa OR 3.13 (1.44-6.81, tres o más eventos de sepsis OR 3.43 (1.62 7.28, sedación prolongada OR 4.09 (1.06-15.73 y corticoide prolongado OR 9.54 (2.06-44.16.  CONCLUSIONES: nuestros resultados muestran que los factores de riesgo para enfermedad ósea metabólica del prematuro fueron peso al nacer menor de 1,000 gramos, displasia broncopulmonar moderada o severa, tres o más eventos de sepsis, sedación y corticoides durante tiempo prolongado.

  9. Rasgos urbanísticos del crecimiento residencial asociado a la burbuja inmobiliaria, 1995-2006

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    Julio Pozueta Echávarri

    2015-06-01

    Full Text Available Posiblemente, el fenómeno urbanístico más sorprendente de los últimos 22 años, ha sido lo que se ha venido en llamar la “burbuja inmobiliaria”, el amplio ciclo inmobiliario expansivo que se desarrolla en España, entre 1995 y 2006, durante el cual se triplica el número de licencias de viviendas concedidas en España, que pasan de una media de 217.863 durante el quinquenio 1990-94 a las 737.186 que se alcanzan en 2006, una cifra más de tres veces superior a la anterior. La “burbuja inmobiliaria” o “tsunami urbanístico”, como también se ha llamado, ha dado lugar a una ingente cantidad de publicaciones, noticias y opiniones y ha sido un tema recurrente en la prensa española durante sus años finales y los primeros de la crisis que le siguió. Sin embargo, aparte de su mera dimensión cuantitativa global, en realidad, los rasgos del crecimiento urbano asociado a la publicitada y debatida “burbuja” son poco conocidos, mucho menos que la evolución de los precios y las ventas, que han centrado la atención pública, y una de las principales razones de este desconocimiento es seguramente la dificultad de contar con datos precisos de un fenómeno cuyo modelado y control es una competencia básicamente municipal, lo que significa que los datos detallados de este proceso están repartidos entre las 8.123 corporaciones municipales que, de acuerdo con el MINHA, componen España.

  10. Eventos adversos temporalmente asociados a VAMENGOC- BC®. Municipio La Lisa, 1998-1999

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    Iván Edelberto Cuevas

    2000-12-01

    Full Text Available Con el objetivo de describir la frecuencia de eventos temporalmente asociados a la vacuna cubana VAMENGOC- BC®, se realizó un estudio observacional de tipo descriptivo, cuyo universo estuvo constituido por los lactantes en las edades comprendidas de tres (3549 y cinco meses (3832 de edad de las áreas de salud del Municipio La Lisa en Ciudad de La Habana. Hubo un 3,21% de niños con eventos adversos, con una mayor frecuencia después de la primera dosis; sin diferencias apreciables por sexo. La clasificación fue de un 52% de tipo sistémico, locales un 19% y no solicitados un 29%. La mayor parte de los niños afectados fue en las primeras 72 horas posteriores a la vacunación, y desaparecieron antes de 72 horas desde su comienzo. Las manifestaciones más frecuentes fueron fiebre (predominó entre todos los eventos adversos con 1,53 casos por 100 vacunados; la induración (0,31 por 100 vacunados, eritema (0,30 por 100 vacunados y el dolor (0,136 por 100 vacunados en el sitio de administración de la vacuna; irritabilidad (0,244 por 100 vacunados y pérdida de apetito (0,311 por 100 vacunados. Los eventos no solicitados más frecuentes fueron la Enfermedad Respiratoria Aguda (0,637 por 100 vacunados, la Enfermedad Diarreica Aguda (0,311 por 100 vacunados y la Otitis Media (0,176 por 100 vacunados. Los eventos adversos serios fueron infrecuentes. No hubo fallecidos y todos los casos se recuperaron en menos de diez días, sin secuelas, discapacidades ni minusvalías

  11. Aspectos socioeconómicos y familiares asociados en niños y adolescentes obesos

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    William José González Cabriles

    2013-01-01

    Full Text Available El estudio es transversal y correlacional donde se analizaron las variables socioeconómicas y familiares de una muestra no probabilística, constituida por 528 familias de niños con obesidad exógena, de 2 a 18 años, provenientes de diversos sectores del país, atendidos en la consulta de primera del Centro de Atención Nutricional Infantil Antímano. El objetivo fue determinar los aspectos socioeconómicos y familiares asociados en niños y adolescentes con obesidad que asistieron al Centro. Los datos se procesaron con el programa SPSS 9.0. Se analizaron las distribuciones de frecuencias y el estadístico Chi-cuadrado para probar asociación entre las variables. El nivel de significancia fue 95%. En las familias de niños obesos se encontró que la mayoría de los jefes de familia eran obesos; las familias con pobreza extrema y la población infantil mayor de 15 años presentaron mayor sedentarismo; por último, las madres en general no participaron en la toma de decisiones en la compra de alimentos y no poseían nociones de alimentación equilibrada que les permitieran planificar la compra de alimentos. Estos aspectos se erigen como claves para ser abordados y resueltos por el trabajador social durante la intervención con el fin de favorecer la recuperación nutricional del niño obeso y su familia.

  12. Factores de riesgo asociados al uso de drogas en estudiantes adolescentes

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    Osorio Rebolledo Ever Agustín

    2004-01-01

    Full Text Available Objetivo Identificar factores de riesgo asociados al uso de drogas lícitas e ilícitas en estudiantes adolescentes de ambos sexos cursantes de educación básica y diversificada de instituciones públicas diurnas. Métodos Con base a un estudio descriptiva, de campo y transversal fue realizado estudio en el año 2002 en el Municipio Naguanagua, Estado Carabobo, Venezuela. Se utilizo un cuestionario anónimo auto aplicado denominado Test Drug Use Screening Inventory (DUSI para adolescentes versión Venezuela, fue respondido por una muestra probabilística sistemática estratificada por año de estudio de estudiantes adolescentes de 12 a 17 años de edad de ambos sexos, de dos instituciones educativas públicas diurnas de educación básica y diversificada. Resultados Las áreas de riesgo alto asociadas al uso de drogas lícitas e ilícitas son las de familia y salud mental; mientras que en las de riesgo moderado se encuentran las áreas de recreación, conducta y escuela; y las de riesgo bajo pares, habilidades sociales y uso de drogas. Los resultados del Índice de Severidad Total, es alto. Esto es un indicador de que el adolescente venezolano presenta más riesgo de uso de drogas lícitas e ilícitas, pero al mismo tiempo presenta menos uso de drogas. Lo que pudiera indicar cómo la presencia de factores de protección interactúan con los factores de riesgo, para modificar el efecto de éstos.

  13. Factores de riesgo asociados al uso de drogas en estudiantes adolescentes

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    Ever Agustín Osorio Rebolledo

    Full Text Available Objetivo Identificar factores de riesgo asociados al uso de drogas lícitas e ilícitas en estudiantes adolescentes de ambos sexos cursantes de educación básica y diversificada de instituciones públicas diurnas. Métodos Con base a un estudio descriptiva, de campo y transversal fue realizado estudio en el año 2002 en el Municipio Naguanagua, Estado Carabobo, Venezuela. Se utilizo un cuestionario anónimo auto aplicado denominado Test Drug Use Screening Inventory (DUSI para adolescentes versión Venezuela, fue respondido por una muestra probabilística sistemática estratificada por año de estudio de estudiantes adolescentes de 12 a 17 años de edad de ambos sexos, de dos instituciones educativas públicas diurnas de educación básica y diversificada. Resultados Las áreas de riesgo alto asociadas al uso de drogas lícitas e ilícitas son las de familia y salud mental; mientras que en las de riesgo moderado se encuentran las áreas de recreación, conducta y escuela; y las de riesgo bajo pares, habilidades sociales y uso de drogas. Los resultados del Índice de Severidad Total, es alto. Esto es un indicador de que el adolescente venezolano presenta más riesgo de uso de drogas lícitas e ilícitas, pero al mismo tiempo presenta menos uso de drogas. Lo que pudiera indicar cómo la presencia de factores de protección interactúan con los factores de riesgo, para modificar el efecto de éstos.

  14. Injuria renal aguda, perfil epidemiológico intrahospitalario y factores asociados al riesgo de muerte

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    Cristian León

    2014-10-01

    Full Text Available La injuria renal aguda (IRA es un evento mórbido de gran impacto en la vida de las personas. La tasa de letalidad de la IRA ha sido un tema relevante y se han estudiado muchos factores relacionados. Objetivos: Determinar el perfil epidemiológico de los pacientes con IRA en un hospital de Lima y los factores asociados a la mortalidad durante el periodo de hospitalización. Material y métodos: Estudio descriptivo, retrospectivo de una cohorte de pacientes incidentes con diagnóstico de IRA. Se calculó la letalidad bruta y la ajustada a tiempo de permanencia hospitalaria. Se usó la regresión multivariante de Cox, así como el mejor modelo para regresión logística binaria asociada a letalidad. Se aceptó una significancia estadística de p<0,05. Resultados: Se identificaron 90 pacientes con IRA en los años 2002, 2003 y 2004 (incidencia de 30, 39 y 21 pacientes/año, respectivamente. Su permanencia hospitalaria fue 13,44 ± 1,66 (promedio±1ES días, la tasa bruta de letalidad 39% y la tasa ajustada 2,89 fallecidos/100 días de hospitalización. Las variables relacionadas al riesgo de muerte en el tiempo fueron el estado de shock, el diagnóstico de sepsis y la disfunción respiratoria al momento de la admisión. Conclusiones: La gravedad clínica como condición al momento de la admisión al centro hospitalario, el estado séptico y la presencia de disfunción respiratoria, fueron los factores que influenciaron en el pronóstico de supervivencia de pacientes con IRA.

  15. FACTORES SOCIODEMOGRÁFICOS Y DE SALUD ASOCIADOS A LA INSTITUCIONALIZACIÓN DE PERSONAS DEPENDIENTES

    Directory of Open Access Journals (Sweden)

    Mercedes Ayuso Gutiérrez

    2010-01-01

    Full Text Available Fundamento: El análisis del efecto que diferentes variables tienen en la institucionalización de las personas dependientes es un tema escasamente estudiado en España. El objetivo del trabajo es analizar qué factores sociodemográficos y del estado de salud pueden influir en la probabilidad de que la persona dependiente viva en una residencia. Métodos: Se realizó un estudio transversal de la población dependiente de la provincia de Cuenca, a partir de una muestra representativa de la población baremada como dependiente en febrero de 2009, obteniéndose información de personas con grados II y III de dependencia. Se estimó un modelo de regresión logística binaria para identificar los factores asociados a la institucionalización de las personas dependientes. Resultados: Los individuos con edades comprendidas entre 65 y 74 años tienen prácticamente 6 veces más probabilidad de estar institucionalizados, frente a no estar institucionalizados, que los de edades inferiores a 65 años; probabilidad que aumenta hasta 16 veces para individuos de edad igual o superior a los 95 años. Vivir en zona urbana multiplica por 3 la probabilidad de institucionalización frente a residir en zona rural. Las personas que siguen tratamientos farmacológicos, tratamientos psicoterapéuticos, o tratamientos rehabilitadores, tienen entre 2 y 4 veces más probabilidad de estar institucionalizados que las que no los siguen. Conclusiones: La edad, el estado civil casado, el lugar de residencia, las variables de salud enfermedades del aparato circulatorio y musculoesqueléticas, y los cuatro tipos de tratamiento a seguir se convierten en las principales variables asociadas a la institucionalización de personas dependientes.

  16. Factores asociados al fracaso académico en estudiantes universitarios de Barranquilla (Colombia

    Directory of Open Access Journals (Sweden)

    Katherine Contreras

    2008-01-01

    Full Text Available El fracaso académico es un problema que afrontan los estudiantes quepresentan un rendimiento académico deficiente, lo cual los lleva en pocotiempo a desertar o son expulsados del sistema educativo. Se considera que es un problema multicausal, pero para afrontarlo es necesario indagar desde los mismos estudiantes qué es lo que más los puede estar afectando.Para indagar sobre los factores asociados a este problema se llevó a cabo un estudio descriptivo con estudiantes de psicología en una universidad privada de Barranquilla (Colombia. Se entrevistó a 38 estudiantes que asistían a un programa exclusivo para aquellos con muy bajo rendimiento académico y que estaban en riesgo de salir del programa o habían sido remitidos por los profesores. Los resultados indican que los estudiantes no recibieron una orientación vocacional adecuada antes de ingresar a los estudios superiores que les permitiera analizar sus capacidades y habilidades con respecto a una carrera profesional. Además manifiestan limitaciones en sus competencias de concentración y atención, en la distribución del tiempo, en la deficiente utilización de técnicas de estudio, y en la poca asistencia a clases por la baja motivación en las actividades académicas. La relación con su familia la consideraron satisfactoria. Se observa que las acciones para reducir el fracaso deben ser emprendidas antes del ingreso a la universidad, con estrategias de estudio y afrontamiento que les brinden a los jóvenes las mejores opciones entre sus intereses y capacidades con las oportunidades que les ofrece la sociedad en la cual vivirán.

  17. A comparison of cup-to-disc ratio estimates by fundus biomicroscopy and stereoscopic optic disc photography in the Tema Eye Survey.

    Science.gov (United States)

    Mwanza, J C; Grover, D S; Budenz, D L; Herndon, L W; Nolan, W; Whiteside-de Vos, J; Hay-Smith, G; Bandi, J R; Bhansali, K A; Forbes, L A; Feuer, W J; Barton, K

    2017-08-01

    PurposeTo determine if there are systematic differences in cup-to-disc ratio (CDR) grading using fundus biomicroscopy compared to stereoscopic disc photograph reading.MethodsThe vertical cup-to-disc ratio (VCDR) and horizontal cup-to-disc ratio (HCDR) of 2200 eyes (testing set) were graded by glaucoma subspecialists through fundus biomicroscopy and by a reading center using stereoscopic disc photos. For validation, the glaucoma experts also estimated VCDR and HCDR using stereoscopic disc photos in a subset of 505 eyes that they had assessed biomicroscopically. Agreement between grading methods was assessed with Bland-Altman plots.ResultsIn both sets, photo reading tended to yield small CDRs marginally larger, but read large CDRs marginally smaller than fundus biomicroscopy. The mean differences in VCDR and HCDR were 0.006±0.18 and 0.05±0.18 (testing set), and -0.053±0.23 and -0.028±0.21 (validation set), respectively. The limits of agreement were ~0.4, which is twice as large as the cutoff of clinically significant CDR difference between methods. CDR estimates differed by 0.2 or more in 33.8-48.7% between methods.ConclusionsThe differences in CDR estimates between fundus biomicroscopy and stereoscopic optic disc photo reading showed a wide variation, and reached clinically significance threshold in a large proportion of patients, suggesting a poor agreement. Thus, glaucoma should be monitored by comparing baseline and subsequent CDR estimates using the same method rather than comparing photographs to fundus biomicroscopy.

  18. Detection of early metabolic alterations in the ocular fundus of diabetic patients by time-resolved autofluorescence of endogenous fluorophores

    Science.gov (United States)

    Schweitzer, D.; Klemm, M.; Quick, S.; Deutsch, L.; Jentsch, S.; Hammer, M.; Dawczynski, J.; Kloos, C. H.; Mueller, U. A.

    2011-07-01

    Measurements of time-resolved autofluorescence (FLIM) at the human ocular fundus of diabetic patients permit the detection of early pathologic alterations before signs of diabetic retinopathy are visible. The measurements were performed by the Jena Fluorescence Lifetime Laser Scanner Ophthalmoscope applying time-correlated single photon counting (TCSPC) in two spectral channels (K1: 490-560 nm, K2:560-700ps). The fluorescence was excited by 70 ps pulses (FWHM) at 448 nm. The decay of fluorescence intensity was triple-exponentially approximated. The frequency of amplitudes, lifetimes, and relative contributions was compared in fields of the same size and position in healthy subjects and in diabetic patients. The most sensitive parameter was the lifetime T2 in the short-wavelength channel, which corresponds to the neuronal retina. The changes in lifetime point to a loss of free NADH and an increased contribution of protein-bound NADH in the pre-stage of diabetic retinopathy.

  19. Comparative study between fundus autofluorescence and red reflectance imaging of choroidal nevi using ultra-wide-field scanning laser ophthalmoscopy.

    Science.gov (United States)

    Zapata, Miguel Angel; Leila, Mahmoud; Teixidor, Teresa; Garcia-Arumi, Jose

    2015-06-01

    To explore the utility of fundus autofluorescence (FAF) and red reflectance (RR) imaging using ultra-wide-field scanning laser ophthalmoscope in choroidal nevi. Retrospective observational case study reviewing clinical data, color, FAF, and RR images of patients with choroidal nevi and comparing the findings. The ultra-wide-field scanning laser ophthalmoscope uses green laser 532 nm and red laser 633 nm that enabled FAF and RR imaging, respectively in separate channels. Superimposition of both images yielded a composite color image. The study included 46 eyes of 45 patients. Nevi were unilateral in 44 patients (98%). Forty-one nevi (89.1%) were located temporally between the macula and the equator. All nevi (100%) were deeply pigmented. The most frequent surface changes were lipofuscin pigments, zones of retinal pigment epithelium atrophy, and retinal pigment epithelium pigment clumps in 31 (67.3%), 18 (39.1%), and 8 eyes (17.3%), respectively. Color photographs were superior to FAF in detecting nevus boundaries and surface changes. Red reflectance correlated strongly with color images, although the nevus boundaries and surface changes were better delineated in RR mode. Red reflectance was superior to FAF in delineating the boundaries and surface changes of the nevus; clear visibility (3+) for RR versus no or poor visibility (0/1+) for FAF. Nevertheless, the areas of retinal pigment epithelium atrophy were better delineated in FAF mode; clear visibility (3+) for FAF versus poor visibility (1+) for FAF. Red reflectance imaging is more sensitive than conventional photography for follow-up of choroidal nevi. Fundus autofluorescence should be considered only as a complementary tool to RR imaging.

  20. Immediate and long-term changes of fundus autofluorescence in continuous wave laser lesions of the retina.

    Science.gov (United States)

    Framme, Carsten; Roider, Johann

    2004-01-01

    To determine whether fundus autofluorescence imaging is able to show changes in retinal pigment epithelium (RPE) fluorescence after thermal laser photocoagulation. In vivo imaging of fundus autofluorescence was performed with a scanning laser ophthalmoscope. A laser with a wavelength of 488 nm was used for excitation of the tissue and autofluorescence was detected above 500 nm using a barrier filter. One hundred eight eyes of 87 patients who had had previous laser treatment were monitored. The appearance and size of the laser lesions were documented and correlated to the time of treatment. Immediate changes were observed prospectively in 13 eyes; long-term follow-up was studied retrospectively in 95 eyes. In all patients but one, autofluorescence was decreased in the area of laser lesions 1 hour after laser treatment. After 1 month, previously decreased autofluorescence in all lesions changed to significantly increased autofluorescence, which was stable up to 6 months after treatment. Mixed forms were present approximately 6 to 12 months after treatment, showing a central island of increased autofluorescence surrounded by a ring of decreased autofluorescence. After 1 to 2 years, lesions again changed to complete dark spots, enlarging later on. RPE destruction and subsequent proliferation after continuous wave laser photocoagulation can be visualized noninvasively by autofluorescence imaging. Immediate decreased autofluorescence may indicate acute damage of the RPE, subsequent increased autofluorescence seems to indicate proliferative behavior of the RPE, and final dark spots can indicate RPE atrophy secondary to a denaturation of neurosensory retinal tissue. Thus, autofluorescence can be used in the long-term monitoring of RPE changes after laser treatment. The enlargement of the laser atrophy zone demonstrates the potential risk of visual loss after central laser photocoagulation even years after treatment.

  1. Correlation between peripapillary retinal nerve fiber layer thickness and fundus autofluorescence in primary open-angle glaucoma

    Directory of Open Access Journals (Sweden)

    Reznicek L

    2013-09-01

    Full Text Available Lukas Reznicek,* Florian Seidensticker,* Thomas Mann, Irene Hübert, Alexandra Buerger, Christos Haritoglou, Aljoscha S Neubauer, Anselm Kampik, Christoph Hirneiss, Marcus Kernt Department of Ophthalmology, Ludwig-Maximilians-University, Munich, Germany *These authors contributed equally to this work Purpose: To investigate the relationship between retinal nerve fiber layer (RNFL thickness and retinal pigment epithelium alterations in patients with advanced glaucomatous visual field defects. Methods: A consecutive, prospective series of 82 study eyes with primary open-angle glaucoma and advanced glaucomatous visual field defects were included in this study. All study participants underwent a full ophthalmic examination followed by visual field testing with standard automated perimetry as well as spectral-domain optical coherence tomography (SD-OCT for peripapillary RNFL thickness and Optos wide-field fundus autofluorescence (FAF images. A pattern grid with corresponding locations between functional visual field sectors and structural peripapillary RNFL thickness was aligned to the FAF images at corresponding location. Mean FAF intensity (range: 0 = black and 255 = white of each evaluated sector (superotemporal, temporal, inferotemporal, inferonasal, nasal, superonasal was correlated with the corresponding peripapillary RNFL thickness obtained with SD-OCT. Results: Correlation analyses between sectoral RNFL thickness and standardized FAF intensity in the corresponding topographic retina segments revealed partly significant correlations with correlation coefficients ranging between 0.004 and 0.376 and were statistically significant in the temporal inferior central field (r = 0.324, P = 0.036 and the nasal field (r = 0.376, P = 0.014. Conclusion: Retinal pigment epithelium abnormalities correlate with corresponding peripapillary RNFL damage, especially in the temporal inferior sector of patients with advanced glaucomatous visual field defects. A

  2. Expectativas, consumo de alcohol y problemas asociados en estudiantes universitarios de la ciudad de México

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    Mora-Ríos Jazmín

    2001-01-01

    Full Text Available OBJETIVO: Establecer la relación entre las expectativas hacia el consumo de alcohol, los patrones de su uso y los problemas asociados a su consumo en una muestra de estudiantes universitarios de la ciudad de México. MATERIAL Y MÉTODOS: Estudio transversal realizado en octubre de 1998, en el que participaron 678 estudiantes, hombres y mujeres entre los 17 y 25 años de edad, provenientes de universidades públicas y privadas. En él se midieron las expectativas a partir de un cuestionario de autorreporte, el Alcohol Expectancy Questionnaire (AEQ, que fue adaptado a esta población obteniendo una consistencia interna global elevada (alpha=0.93. RESULTADOS: Del total de los estudiantes, 31% presentó un consumo alto (mayor a cinco copas por ocasión de consumo en el último año, principalmente en los varones, mientras que 17% fueron no consumidores. Mediante un modelo estructural de ecuaciones se estudió la relación entre las subescalas de expectativas, el patrón de consumo y problemas asociados. El análisis de varianza mostró una relación estadísticamente significativa entre seis subescalas de expectativas (el alcohol como facilitador de la interacción grupal, expresividad verbal, desinhibición, incremento de la sexualidad, reducción de la tensión psicológica e incremento de la agresividad y las variables sexo, consumo de alcohol y problemas asociados (F=5.23, gl=1, phttp://www.insp.mx/salud/index.html

  3. Factores asociados a la infestación intradomiciliaria por Aedes aegypti en el distrito de Tambogrande, Piura 2004

    Directory of Open Access Journals (Sweden)

    Edwar J. Pozo

    2007-04-01

    Full Text Available Objetivos: Determinar los factores asociados para la infestación de las viviendas por Aedes aegypti en el distrito de Tambogrande, Piura. Materiales y métodos: Realizamos un estudio de casos y controles en la capital del distrito de Tambogrande, en diciembre de 2004. Consideramos como vivienda-caso (Vc a la vivienda positiva a la infestación por Ae. aegypti, y vivienda-control (Vo a la vivienda negativa a la infestación por Ae. aegypti en por lo menos un año, de acuerdo a los registros de las actividades de control larvario. Por cada caso consideramos dos controles. La encuesta incluyó factores ambientales, sociales y culturales, y se aplicó a la persona encargada del cuidado de la vivienda. Los factores asociados con un valor de p<0,10 en el análisis bivariado, fueron ingresados a un modelo de regresión logística para estimar los OR ajustados y los intervalos de confianza al 95% (IC. Resultados: Encuestamos 60 Vc y 124 Vo. Los factores asociados encontrados en modelo logístico múltiple fueron la presencia de botellas dentro de la vivienda (OR: 7,66; IC: 2,95-19,84, vivienda ubicada a menos de 200 m de una llantería (OR: 2,90; IC: 1,13-7,48, vivienda ubicada a menos de 200 m. de una maderera (OR: 2,76; IC: 1,14-6,66 y tener un jardín en el interior de la vivienda (OR: 2.31; IC: 0,98-7,48. Tener una trabajadora del hogar en la vivienda fue un factor protector (OR: 0,07; IC: 0,014- 0,37. Conclusiones: Los factores identificados deben ser tomados en cuenta para el desarrollo de programas de control vectorial en Tambogrande.

  4. Efectos adversos asociados a la vacunación anti-gripal en pediatría

    OpenAIRE

    Martín Moreno Vicente; Molina Cabrerizo María del Rosario; Sotillo Rincón María Jesús; Gómez Gómez Carlos; Alvarez Gómez Julia

    1998-01-01

    FUNDAMENTO: las dificultades para valorar adecuadamente la morbimortalidad por gripe en la infancia y las limitaciones de la propia vacuna, hacen que su uso en esta etapa siga siendo limitado. El objetivo del presente estudio es valorar los efectos adversos asociados a la vacunación antigripal en niños. MÉTODOS: estudio prospectivo realizado en las campañas 92/93, 93/94 y 97/98 en 105 niños de Navalcarnero, con vacuna antigripal de virus fraccionados e inactivados con las cepas vacunales reco...

  5. Factores asociados a recibir la vacunación antigripal en profesionales de atención primaria

    OpenAIRE

    Josep Montserrat-Capdevila; Pere Godoy; Josep Ramon Marsal; Ferran Barbé-Illa

    2015-01-01

    Objetivo: Conocer la cobertura vacunal antigripal en profesionales de atención primaria y determinar los factores asociados a la vacunación (temporada 2013-2014). Métodos: Estudio transversal realizado a 287 profesionales que cumplimentaron un cuestionario que incluía preguntas sobre conocimientos, creencias y actitudes frente la gripe y la vacunación. Se determinó la cobertura y aquellas variables asociadas a recibir la vacunación, utilizando modelos de regresión logística no condicional....

  6. Riesgo suicida y factores asociados en adolescentes de tres colegios de la ciudad de Manizales (Colombia, 2013

    Directory of Open Access Journals (Sweden)

    Diana Carolina Aguirre Flórez

    2015-07-01

    Full Text Available Objetivo: Ésta investigación pretende determinar el factor de riesgo suicida según la escala de Plutchik y factores asociados en estudiantes de octavo a once grado de bachillerato de tres colegios de Manizales (Colombia.  Materiales y métodos: Estudio  de corte transversal con una población de 322 estudiantes de tres colegios de estrato social II y III de la ciudad de Manizales, que cursaban los grados octavo a once de bachillerato. Se aplicó el cuestionario de Plutchik para riesgo suicida, se aplicaron otros cuestionarios para factores asociados. Resultados: El 16,5% presentaron factor de riesgo suicida según la escala de Plutchik, el acoso entre partes presentó un índice de intensidad entre alta y muy alta de 58,1%, el 38,5% tuvo buena funcionalidad familiar, el 18% presentó depresión, la baja autoestima fue de 19,6%, el 11,8% presentaron dependencia alcohólica, el 23,3% mostraron trastorno de conducta alimentaria, el consumo de sustancias psicoactivas y cigarrillo fue de 31,4% y 13,4% respectivamente. Los siguientes factores asociados presentaron relación significativa: funcionalidad familiar (p=0,000, depresión (p=0,000, dependencia alcohólica (p=0,001, autoestima (p=0,000, trastornos de conducta alimentaria (p=0,000, acoso escolar (p=0,000, consumo de cigarrillo (p=0,000 y consumo de sustancias psicoactivas (p=0,001. Conclusiones: El estudio muestra FR suicida según Plutchik superior al de otras poblaciones similares, además se encontraron factores asociados entre los cuáles sobresalen, la depresión y la disfuncionalidad familiar. Un hallazgo muy importante fue el acoso entre pares, el cual aumenta en gran proporción el riesgo suicida. No se encontró relación significativa entre FR suicida y estrato social.

  7. Intervención psicosocial y educativa para prevención de riesgos asociados a procesos migratorios

    OpenAIRE

    Pinillos, Mónica

    2012-01-01

    Con este artículo se trata de describir los principales modelos teóricos formulados para analizar la vinculación entre el proceso migratorio y los factores de riesgo para la salud psíquica asociados al mismo. Se describen los trastornos que pueden surgir y se presentan unas pautas de prevención e intervención. Se propone una intervención integral a través de un modelo multivariado, con programas comunitarios y de atención psicológica. Se insiste en la necesidad de tener presentes los factores...

  8. Factores biopsicosociales asociados a la disfunción sexual femenina en una población mexicana

    OpenAIRE

    Vega M, Genaro; Flores C, Patricia Jezabel; Ávila M, Javier; Becerril S, Alma; Vega M, Alfredo Jesús; Camacho C, Nicolás; García S, Pablo

    2014-01-01

    Objetivo: Determinar los factores biopsicosociales asociados a la disfunción sexual femenina en una población mexicana. Métodos: Estudio comparativo en mujeres que acudieron como acompañantes a una Unidad de Medicina Familiar de Querétaro, México. Se aplicaron las encuestas de Laumman, Chávez y Velazco, Faces III, y Grajales para valorar sexualidad, funcionalidad conyugal, funcionalidad familiar y estado de la autoestima. Los resultados fueron analizados con Odds Ratios, Chi cuadrado y t de S...

  9. Prevalencia de disfunción sexual femenina y factores asociados, Hospital José Carrasco Arteaga

    OpenAIRE

    Matute Ortega, Viviana Soledad

    2014-01-01

    Antecedentes: La disfunción sexual femenina (DSF) incluye múltiples desórdenes frecuentes presentes en una de cada tres mujeres, razón por la que es necesario el conocimiento de la fisiología de la respuesta sexual femenina y sus alteraciones. Objetivo: Determinar la prevalencia de disfunción sexual femenina y los factores asociados. Metodología: Estudio transversal en 303 pacientes que fueron entrevistadas en las dependencias del servicio de Ginecología del Hospital José Carrasco A...

  10. Prevalencia y factores asociados a desnutrición hospitalaria en un hospital general: Perú, 2012

    OpenAIRE

    L. E. Veramendi-Espinoza; J. H. Zafra-Tanaka; O. Salazar-Saavedra; J. E. Basilio-Flores; E. Millones-Sánchez; G. A. Pérez-Casquino; L. M. Quispe-Moore; M. E. Tapia-Vicente; D. I. Ticona-Rebagliati; N. B. Asato; L. Quispe-Calderón; H. J. Ruiz García; A. Chia-Gil; D. E. Rey-Rodríguez; B. T. Surichaqui

    2013-01-01

    Introducción: La desnutrición hospitalaria es un problema prevalente que genera mayor morbi-mortalidad, peor respuesta al tratamiento, mayor estancia y costo hospitalario. Objetivos: Determinar la prevalencia y factores asociados a desnutrición hospitalaria en un hospital general peruano. Métodos: Estudio analítico transversal de 211 pacientes en servicios de Medicina y Cirugía. Se analizó variables demográficas, clínicas e indicadores antropométricos. El análisis multivariado fue de regresió...

  11. Factores asociados al desplazamiento activo en bicicleta al colegio en el Distrito Bogotá, Colombia. Estudio FUPRECOL

    OpenAIRE

    Beltrán Ahumada, César Augusto

    2016-01-01

    Introducción: El transporte activo (TA) puede ser una oportunidad para incrementar los niveles de actividad física diarios de los niños y adolescentes, además de destacarse como una estrategia práctica, accesible y sostenible a largo plazo. Objetivos: El objetivo del presente estudio es doble: Analizar los patrones de desplazamiento activo en bicicleta al y desde el centro educativo, y b) Identificar los factores asociados al uso de la bicicleta como TA; en una muestra de niños...

  12. Factores resilientes asociados al rendimiento académico en estudiantes pertenecientes a la Universidad de Sucre (Colombia)

    OpenAIRE

    Sonia Carolina Peralta Díaz; Andrés Fernando Ramírez Giraldo; Hernando Castaño Buitrago

    2006-01-01

    El objetivo de la investigación fue determinar si existen factores resilientes asociados al rendimiento académico en una muestra de estudiantes universitarios. Dicha muestra estuvo compuesta por 345 estudiantes, distribuidos en 2 grupos, bajo rendimiento y alto rendimiento, entre los 16 y 38 años de edad. El instrumento utilizado fue el cuestionario de resiliencia para estudiantes universitarios (cre-u). Los resultados, después de aplicar el modelo estadístico de regresión logí...

  13. Factores familiares asociados a codependencia en enfermeras de un hospital de Cancún, Quintana Roo, México

    OpenAIRE

    Ramírez-Amaro, Margarita; Martínez-Torres, Jorge; Ureña Bogarín, Enrique Leobardo

    2014-01-01

    Objetivo: Identificar los factores familiares asociados a la presencia de codependencia en las enfermeras de un hospital regional en Cancún, Quintana Roo, México. Diseño: Estudio transversal, comparativo. Emplazamiento: Ciudad de Cancún (México). Participantes: Mediante un muestreo aleatorizado se seleccionaron 200 enfermeras que cumplieron los criterios de selección (tener pareja de más de un año, acudir a trabajar el día de la entrevista, tener contrato laboral al momento del estud...

  14. Factores de riesgo relevantes asociados a las malformaciones congénitas en la provincia de Cienfuegos, 2008-2013

    OpenAIRE

    Santos Solís, Mailé; Vázquez Martínez, Vivian; Torres González, Cristobal; Torres Vázquez, Grisel; Aguiar Santos, Daniela; Hernández Monzón, Hernán

    2016-01-01

    Fundamento: las malformaciones congénitas contribuyen de forma importante a la mortalidad infantil. Producen secuelas y resulta difícil su prevención. Objetivo: determinar factores de riesgo relevantes asociados a la aparición de malformaciones congénitas. Métodos: estudio observacional de casos y controles no pareados realizado en Cienfuegos en el período de enero de 2008 a diciembre de 2013, sobre un universo de 27 002 gestantes; las mujeres registradas con fetos o recién nacidos con malfor...

  15. Tromboembolismo pulmonar asociado al síndrome de la vena cava superior de origen trombótico

    OpenAIRE

    Barrera-López, Ana Madeleine; Cortés-P., Luis Arcadio; Salazar-C., Erika María

    2016-01-01

    Se describe el caso de un paciente masculino de 32 años de edad, quien consulta al servicio de urgencias con historia clínica del síndrome de la vena cava superior, en el estudio de la angiotomografía pulmonar, se demuestra embolismo pulmonar izquierdo, trombosis de la vena yugular interna derecha y confluente yugulo subclavio. No hay evidencia de asociación con neoplasia, infecciones o enfermedades del tejido conectivo, siendo el único factor de riesgo asociado para la trombosis, hiperviscoc...

  16. Ácaros asociados a dos especies de Odontotaenius(Coleóptera: Passalidae) en México

    OpenAIRE

    Barrios-Torres, Pilar Liliana; Villegas-Guzmán, Gabriel A.

    2015-01-01

    Resumen:Los ácaros se relacionan con pasálidos, estableciendo una asociación temporal para transportarse (foresia). Se conocen más de 200 especies de ácaros forontes de pasálidos. El objetivo del estudio fue conocer la diversidad de ácaros asociados a dos especies de Odontotaenius,así como determinar sus sitios de fijación. Se recolectaron pasálidos de troncos en descomposición en seis estados de México. Se encontraron 80 pasálidos con ácaros (64 de O. zodiacusy 16 de O. striatopunctatus),en ...

  17. Evaluación de factores asociados a la ansiedad social y a otras psicopatologías en adolescentes

    OpenAIRE

    Zubeidat, Ihab; Fernández Parra, Antonio; Sierra, Juan Carlos; Salinas, José María

    2008-01-01

    Introducción El estudio de factores asociados a la ansiedad y fobia social constituye un tema de reciente interés. Concretamente, la timidez infantil parece actuar como una expresión temprana de la fobia social que más tarde se puede consolidar como cuadro clínico. La percepción de los hijos sobre la presencia de ciertas psicopatologías y de determinados estilos de crianza de los padres se asocia a la aparición de la fobia social en la adolescencia. El trastorno de ansiedad social durante la ...

  18. Coeficiente intelectual y factores asociados en niños escolarizados en la ciudad de medellín, colombia

    OpenAIRE

    Alvarez-Uribe, Martha Cecilia; Zapata-Zabala, Maryoris E.; Aguirre-Acevedo, Daniel C.; Cadavid-Castro, Martha A.

    2013-01-01

    Objetivo Analizar el coeficiente intelectual y los factores asociados en niños escolarizados de 6 a 8 años en las comunas Nororiental y Norocidental de la ciudad de Medellín-Colombia. Materiales y Métodos Se realizó un muestreo aleatorio simple, polietápico y estratificado según grado escolar y comuna, la muestra estuvo constituida por 423 niños de ambos sexos. El coeficiente intelectual se evaluó con la Escala de Inteligencia Wechsler para Niños WISC-IV y la estimulación psicosocial con Obse...

  19. Coeficiente intelectual y factores asociados en niños escolarizados en la ciudad de Medellín, Colombia

    OpenAIRE

    ZapataZabala, Maryoris E; ÁlvarezUribe, Martha C; AguirreAcevedo, Daniel C; CadavidCastro, Martha A

    2012-01-01

    ObjetivoAnalizar el coeficiente intelectual y los factores asociados en niños escolarizados de 6 a 8 años en las comunas Nororiental y Norocidental de la ciudad de MedellínColombia. Materiales y MétodosSe realizó un muestreo aleatorio simple, polietápico y estratificado según grado escolar y comuna, la muestra estuvo constituida por 423 niños de ambos sexos. El coeficiente intelectual se evaluó con la Escala de Inteligencia Wechsler para Niños WISCIV y la estimulación psicosocial con Observat...

  20. Factores de riesgo asociados al estado nutricio en lactantes que son atendidos en guarderías

    OpenAIRE

    Vásquez-Garibay, Edgar M; Ávila-Alonso, Eneida N; Contreras-Ramos, Tania; Cuellar-Espinosa, Luz A; Romero-Velarde, Enrique

    2007-01-01

    Introducción. Objetivo: identificar factores asociados al estado nutricio en lactantes de 3 a 12 meses de edad que acuden a guarderías en Guadalajara. Material y métodos. En un estudio transversal, se incluyeron 123 lactantes de 3 a 12 meses de edad de cinco guarderías del Instituto Mexicano del Seguro Social de Guadalajara. Se consideró déficit en índices de longitud/edad, peso/edad y peso/longitud con puntuación Z < -l desviación estándar (DE). Se exploraron variables sociodemográficas, eco...

  1. Prevalencia y factores asociados a sobrepeso y obesidad infantil en escuelas públicas y privadas de Tegucigalpa, Honduras

    OpenAIRE

    Ramírez-Izcoa, Alejandro; Sánchez-Sierra, Luis Enrique; Mejía-Irías, Carlos; Izaguirre González, Allan Iván; Alvarado-Avilez, Cindy; Flores-Moreno, Rosaura; Yareny Miranda, Kyrian; M-Díaz, Claudia; Grissel Aguilar, Videlda; Rivera, Elena E

    2017-01-01

    Objetivo: Comparar los factores asociados de sobrepeso y obesidad en los niños de escuelas públicas y privadas de la colonia Kennedy, Tegucigalpa, Honduras. Materiales y Métodos. Se estudiaron 357 escolares entre 6 y 11 años. Se realizó evaluación nutricional, frecuencia de consumo, hábitos y prácticas alimentarias y actividad física mediante encuesta. Se excluyeron escolares con sobrepeso y obesidad secundaria a una patología de base. La información fue analizada con el programa Epi-info, se...

  2. Factores de riesgo asociados a la seroprevalencia de anticuerpos a Neospora caninum en ganado lechero de Aguascalientes, México

    OpenAIRE

    Rocío Conzuelo Sierra; Leticia Medina-Esparza; Miguel Ramos Parra; Zeferino García-Vázquez; Carlos Cruz-Vázquez

    2011-01-01

    El objetivo del presente trabajo fue identificar potenciales factores de riesgo, incluyendo laposible presencia de contaminación del agua de bebida con ooquistes del parásito, asociados con la seroprevalencia de anticuerpos a N. caninum en hatos lecheros de Aguascalientes, México. Se tomaron muestras de suero sanguíneo de 150 vacas, mismas que fueron analizadas por la técnica de ELISA, se detectó la presencia de ADN de N. caninum en el agua de bebida mediante una prueba de PCR anidada, y se a...

  3. Factores asociados a tratamiento quirúrgico en pacientes con obstrucción intestinal por adherencias

    OpenAIRE

    Guataquira Sierra, Nidya Consuelo

    2015-01-01

    El manejo de la obstrucción intestinal por adherencias es un reto para cualquier especialista en Cirugía debido a que existe controversia sobre el alcance del manejo médico y el momento adecuado para llevar el paciente a cirugía para la resolución del cuadro clínico. En el presente trabajo se pretende, identificar los factores asociados a tratamiento quirúrgico en pacientes con obstrucción intestinal por adherencias. Metodología: Se realizó un estudio de casos y controles en una relación ...

  4. Factores asociados al bullying en instituciones de educación superior

    Directory of Open Access Journals (Sweden)

    Mawency Vergel Ortega

    2016-08-01

    Full Text Available El artículo es el resultado de la fase I del proyecto de investigación "Impacto de la comunidad de aprendizaje en el desarrollo de competencias e indicadores de innovación en la enseñanza", adelantado por la Universidad Francisco de Paula Santander, Colombia. El objetivo es analizar los factores que inciden en el bullying en estudiantes de instituciones de educación superior. La investigación sigue un enfoque cuantitativo, diseño transversal, con técnica de análisis factorial y red neuronal. La muestra la constituyen 571 estudiantes de universidades del departamento de Norte de Santander. Resultados: con una media de edad de 19,62±0,96 años, la prevalencia del bullying identificada en el estudio fue de 11,11%, y resultó más frecuente en el género femenino, en alumnos más jóvenes, homosexuales. Los factores de riesgo para las víctimas fueron: características físicas y sicológicas (χ2=21,59, p=0,000, OR2,86, IC95% 1,82-4,5, tipo y forma de acoso (χ2=31,23, p=0,000, OR5,79, IC95% 2,9-11,4; las causas del bullying con mayor frecuencia de victimización se relacionan con orientación sexual (28,6%, apariencia del cuerpo (16,2%, raza (6,8%, religión (2,5%, región de origen (1,7%. Conclusión: los factores asociados al bullying en universidades son: tipo y forma de acoso, programas de prevención institucional, perfil de la víctima, causas que generan la situación de acoso y percepciones hacia el bullying; el género y la orientación sexual explican la presencia de acoso en instituciones de educación superior en Norte de Santander.

  5. Factores asociados al empleo de varios antibióticos en pacientes clínicos

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    Ioanna Mir Narbona

    2012-12-01

    Full Text Available Objetivo: identificar factores asociados con el empleo de varios antibióticos en pacientes clínicos. Métodos: se realizó un estudio de casos y controles en pacientes con infección, egresados de los servicios clínicos en el Hospital Docente Clínicoquirúrgico "Joaquín Albarrán" entre mayo de 2008 y diciembre de 2011. Se consideró caso al paciente que utilizó tres o más antibióticos. Se obtuvo la siguiente información: edad, sexo, antecedentes patológicos personales, tiempo de inicio de los síntomas sugestivos de un proceso infeccioso, uso previo de antibióticos, signos vitales y estado de conciencia al ingreso, resultados de estudios hematológicos y de química sanguínea, estudios radiográficos de tórax, diagnóstico de infección nosocomial y uso inadecuado de antimicrobianos. Se compararon las frecuencias mediante las pruebas de homogeneidad y prueba exacta de Fisher, pruebas t y de Wilcoxon. Se empleó la regresión logística para la identificación de los factores de riesgo. Resultados: Se estudiaron 92 casos y 184 controles. El riesgo de empleo de varios antibióticos se incrementó 2,68 veces por cada grado centígrado que se encontró elevada la temperatura del paciente (OR= 2,68; IC 95 % 1,21-5,94, 7 veces si existió alteración del nivel de conciencia (OR= 7,32; IC 95 % 1,88-28,55, 3,88 veces si se diagnosticó infección nosocomial y 9,98 veces si se consideró inadecuado el uso de antimicrobianos. Conclusiones: Los factores de riesgo para el uso de varios antibióticos identificados pueden contribuir a elaborar estrategias de control de la calidad de prescripción de antimicrobianos.

  6. Factores de riesgo asociados con las gastropatías. Trinidad, Sancti Spíritus

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    Kirenia Castellanos Sánchez

    2013-07-01

    Full Text Available Fundamento: es importante identificar los factores que incrementan el riesgo de complicaciones gastrointestinales serias, así como, determinar la conducta a seguir para reducirlas. Objetivo: identificar los factores de riesgo asociados con las gastropatías en pacientes atendidos en consulta de gastroenterología. Métodos: se diseñó un estudio de casos y testigos los cuales fueron seleccionados a partir de los pacientes que asistieron a la consulta de gastroenterología de un policlínico de Trinidad, Sancti Spíritus, durante el año 2008. Se incluyeron 104 casos de gastropatías diagnosticadas por endoscopia y 208 testigos. Se analizaron como variables: edad, sexo, las exposiciones al hábito de fumar, la ingestión de café, bebidas alcohólicas y medicamentos antiinflamatorios no esteroideos. Se utilizó la regresión logística dicotómica para controlar el sesgo de confusión, después de la cual se calculó el Riesgo atribuible poblacional porcentual y la curva de dosis respuesta. Resultados: se identificaron como factores de riesgo independientes para las gastropatías: la ingestión de antiinflamatorios no esteroideos (RP 4,50 IC; 2,60-7,80 y RAP % 56,75 IC; 37,50-71,83 con una curva de dosis respuesta significativa para la exposición en tabletas diarias y meses de consumo; el hábito de fumar (RP 2,82 IC; 1,65-4,84 y RAP % 38,97 % IC; 18,57-57,40, con una curva de dosis respuesta significativa para la exposición en cigarrillos diarios y en años de consumo. Los antiinflamatorios no esteroideos identificados como riesgos independientes fueron la indometacina, el ibuprofeno y la aspirina. El incremento de 1 año de edad también representó un riesgo en esta serie. Conclusiones: el hábito de fumar y la ingestión de indometacina, ibuprofeno y aspirina representaron riesgos independientes para contraer una gastropatía. Los médicos deben tener en cuenta los efectos de estos medicamentos para no prescribirlos en altas dosis y por

  7. Control de configuraciones peligrosas en instalaciones con riesgo asociado // Hazardous configurations control in risk related facilities

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    Antonio Torres - Valle

    2010-05-01

    Full Text Available ResumenEl control de configuraciones peligrosas en instalaciones con riesgo asociado es una aplicación delos Análisis Probabilistas de Seguridad (APS previos de las mismas. Una opción de mayor alcancees el uso de monitores de riesgo los que permiten la detección en tiempo real de talesconfiguraciones. Dada la complejidad de los APS y de los monitores de riesgo, esta tarea requiere depersonal experto. El documento presenta un método cualitativo de control de configuracionespeligrosas basado en matrices de dependencias. El algoritmo, informatizado en el códigoCONFIGURACION, puede ser aplicado sin necesidad de APS previos ni uso de monitores de riesgo.La sencillez del método justifica su extensión a instalaciones donde tales herramientas no se handesarrollado, permitiendo así la detección de las configuraciones peligrosas durante su explotación yelevando la seguridad de las plantas. Un sistema similar al descrito se utiliza como ayuda en laoperación de la central nuclear de Embalse. El artículo muestra el uso del método utilizando comobase un sistema de seguridad simplificado.Palabras claves: control de configuración, Análisis Probabilista de Seguridad (APS, matriz de___________________________________________________________________________AbstractThe hazardous configurations control in risk related facilities is an application of the previousProbabilistic Safety Analysis (PSA. A more complete option is the risk monitoring for the on-linedetection of these configurations. The expert personnel are required for this task take into account thecomplexity of the PSA and risk monitor. The paper presents a method of configuration control, basedon dependence matrixes. The algorithm is included in a computer code called CONFIGURACION, todetermine these situations in a qualitative way, without previous PSA results or using a Risk Monitor.The simplicity of the method warrants its application to facilities where these tools have not

  8. Factores de riesgo reproductivo asociados al cáncer mamario, en mujeres colombianas

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    Patricia Olaya-Contreras

    1999-06-01

    Full Text Available INTRODUCCIÓN: El cáncer de mama desde 1992 ha sido la segunda causa de muerte femenina en Colombia (tasa promedio anual de 4,5*100.000 hab. y se reporta una tendencia ascendente por este tipo de neoplasia, y la información sobre los potenciales factores de riesgo del cáncer de la mama en los países Latinoamericanos es escasa. Los objetivos del trabajo fueron probar la protección ofrecida por la lactancia materna, y establecer los factores reproductivos asociados al cáncer de mama en Colombia. MÉTODOS: Se realizó un estudio de casos y controles hospitalarios pareados por edad (+ 2 años de Julio 1995 a Marzo 1996 en Bogotá. La población de estudio quedó constituída por 171 casos histopatológicamente definidos y 171 controles. La historia reproductiva y sociodemográfica fué recolectada a través de un cuestionario y se utilizó la técnica de regresión logística condicionada para el análisis estadístico de la información. RESULTADOS: Se encontraron como factores de riesgo: la nuliparidad , al contrario de las mujeres con paridades mayores de 3 hijos (OR=3,35 IC 1,4 - 8,0, la edad al primer nacimiento (>20 años vs. menores de 20. OR= 1,83 IC 0,7 - 4,8, el antecedente familiar de cáncer de mama y la lactancia al primer hijo (OR=0,09 IC 0,01-0,64 de 1-11 meses y OR= 0,01 IC 0,00-0,14 para los 12 meses y la lactancia acumulada por encima de los 24 meses (p=0,001 prueba de tendencia como principales factores protectores de la enfermedad. CONCLUSIONES: El estudio confirma la importancia de enfocarse en la promoción de la lactancia prolongada y ratifica que el nivel socioeconómico puede determinar los estilos de vida y los eventos reproductivos de las mujeres, explicando el aumento en la mortalidad por cáncer de mama en los países Latinoamericanos, con perfiles de fecundidad y factores de riesgo para el cáncer de mama, similares a los de los países desarrollados.

  9. Síndrome hemofagocítico asociado con dengue hemorrágico

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    Ernesto Rueda

    2002-06-01

    Full Text Available El síndrome hemofagocítico se caracteriza por proliferación histiocítica con fagocitosis de células hemáticas que ocasionan citopenia. Ha sido relacionado antes con diversas infecciones, principalmente por virus. Informamos de tres pacientes con síndrome hemofagocítico secundario a dengue hemorrágico, confirmado por exámenes específicos de laboratorio, quienes fueron internados en el Hospital Universitario Ramón González Valencia de Bucaramanga, Colombia, durante los últimos dos años. Los tres pacientes fueron escolares que presentaron dengue hemorrágico y manifestaron dolor abdominal intenso, fiebre prolongada, hipotensión y hepatomegalia dolorosa; los exámenes paraclínicos mostraron plaquetopenia, anemia y leucopenia; en la ecografía abdominal se observó colecistitis acalculosa y en todos los aspirados de medula ósea se encontraron histiocitos fagocitando células hemáticas de la serie eritroide, mieloide o plaquetaria. Se definió y clasificó el síndrome hemofagocítico, según la Sociedad Internacional de Histiocitosis, en tres grandes clases, recalcando que los casos informados corresponden a histiocitosis clase II y, más específicamente, al síndrome hemofagocítico secundario. Se mencionan las diversas asociaciones de este síndrome con infecciones, principalmente virales, y otras enfermedades no infecciosas; se hace diferenciacion entre síndrome hemofagocítico familiar o primario y el secundario. Finalmente, se enfatiza que los tres pacientes con este síndrome asociado con dengue hemorrágico tuvieron una evolución atípica durante el curso de su enfermedad; la fiebre prolongada y el dolor abdominal persistente fueron los síntomas más importantes. Los autores recomiendan realizar un aspirado de médula ósea como parte de los estudios para el diagnóstico diferencial de casos atípicos de dengue, especialmente con fiebre prolongada, buscando la posibilidad de un síndrome hemofagocítico secundario.

  10. Factores de riesgo asociados a la demencia degenerativa en pacientes geriátricos

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    Alejandro Rodríguez Constantín

    2003-04-01

    Full Text Available Se realizó un estudio analítico de tipo caso-control, para determinar factores de riesgo asociados a la aparición de demencia degenerativa en pacientes geriátricos pertenecientes al Consejo Popular "Los Maceo", del Policlínico Docente "Carlos J. Finlay", de la ciudad de Santiago de Cuba, desde septiembre a diciembre del año 2000. La muestra se constituyó con 22 casos identificados previamente como dementes degenerativos por el Equipo Multidisciplinario Gerontológico y 66 controles. Se aplicó una encuesta y se realizó el análisis de los resultados obtenidos. Se calcularon los odds radio (OR correspondientes a cada variable. El bajo nivel de escolaridad (OR=3,99, y el antecedente patológico familiar de demencia (OR=3,01 fueron identificados como factores de riesgo. No presentaron asociación causal las variables sexo (OR=1,46; modificaciones intensas del tono emocional (OR=1 y cambio brusco repetitivo del entorno habitacional (OR=1. La ejercitación de la capacidad intelectual después de los 60 años (OR=0,8 se consideró factor protector.A case control-type analytical study was made to determine the risk factors associated to the occurrence of degenerative dementia in old patients living in the people´s council "Los Maceo", whose population is taken care of by "Carlos J. Finlay" teaching polyclinics in Santiago de Cuba City. The sample was made up of 22 cases previously diagnosed as degenerative dements by the Multidisciplinary Gerontology Team and 66 controls. A survey was administered and the results achieved were analyzed. Odd ratios of each variable were estimated. Low educational level (OR=3,99 and the pathological family history of dementia (OR = 3.01 were identified as risk factors. No causal relation was observed among sex, intensive changes in emotional state and sudden repetitive change of the living environment (0R=1. The exercising of intellectual abilities after 60 years of age was considered to be a protective factor.

  11. Tratamiento de agrandamiento gingival inducido por fenitoina asociado a placa bacteriana

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    Carmen Julia Rovira

    2013-10-01

    Full Text Available ResumenLa ingesta de algunos medicamentos puede producir un sobre crecimiento de las encías. Se reportan medicamentos tales como los bloqueadores de los canales de calcio, inmunosupresores, anticonvulsivantes que producen estos efectos adversos. Múltiples casos de agrandamientos gingivales están asociados a la ingesta de Fenitoína. El tratamiento de los agrandamientos gingivales inducidos por drogas por lo general es quirúrgico, pero mantener un buen control de placa bacteriana puede evitar en muchos casos que se presente un exagerado aumento de volumen gingival. Se presenta un caso de agrandamiento gingival en paciente masculino de 22 años de edad, bajo tratamiento antiepiléptico con fenitoína. Al examen clínico se observó aumento del volumen gingival de forma generalizada, en maxilar superior e inferior, predominante en sector anterior, produciendo ardor y sangrado durante el cepillado y la ingestión de alimentos. Al sondaje presenta múltiples pseudobolsas en los diferentes cuadrantes. La radiografía panorámica reveló pérdida ósea moderada horizontal, predominante en el sector posterosuperior, posteroinferior y anteroinferior. El plan de tratamiento consistió en fase higiénica, instrucción y motivación en higiene oral a la madre, gingivectomía y gingivoplastía en ambos maxilares. (DUAZARY 2011 No. 2, 226 - 231Abstract The importance of endodontic treatment is to achieve a complete filling and sealing of the root canal to prevent the transport of contaminants to and from root canal, with materials compatible with the surrounding tissues. Occasionally a situation may arise in which the purpose of the maintenance of working length is compromised such as overenlargement. This situation allows the extrusion of filling materials, mainly sealer cements, causing post treatment complications such as inflammatory reactions, injury to adjacent structures (orbital pain, inferior alveolar nerve injury, headache, etc., and infections

  12. Prevalencia de microorganismos asociados a secreción genital femenina, Argentina

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    Di Bartolomeo Susana

    2002-01-01

    Full Text Available OBJETIVO: Hay un aumento significativo de pacientes con Secreción Genital Femenina, en el Sector Público del gran Buenos Aires. Fue necesario actualizar la prevalencia de los microorganismos asociados a los efectos de revisar el apoyo necesario de laboratorio y ajustar las medidas de prevención y control. MÉTODOS: Se incorporan a este estudio, la totalidad de los casos atendidos (1997-1998: 84 adolescentes (15 a 19 años y 784 adultas (20 a 60 años sintomáticas. El protocolo incluye (secreción vaginal y endocervical detección de Neisseria gonorrhoeae, Streptococcus agalactiae, Trichomonas vaginalis, Candida spp y vaginosis bacteriana. Aplicando métodos específicos directos y cultivo, Chlamydia trachomatis (detección de antígeno, Ureaplasma urealitycum y Mycoplasma hominis (cultivos fueron estudiados en parte de la población total. RESULTADOS: El aumento de la demanda de consulta fue continuo desde 1997 y aumentó 2.10 veces del primero al último semestre de 1998. En las mujeres adultas se encontró: vaginosis bacteriana, 23,8%; Candida spp 17,8%; S. agalactiae 5,6%; T. vaginalis 2,4%. En 50,3% no se detecto ninguno. En adolescentes se detectó: vaginosis bacteriana, 17,8%; Candida spp 29,7%; S. agalactiae 3,6%, T. vaginalis 2,4%: En 46,4% de los casos el resultado fue negativo. En el grupo de mujeres adultas sintomáticas, no en la totalidad, se detectó: C. trachomatis (7/400 1,76%, U. urealyticum (209/340 61,4% y M. hominis (45/272 16,5%. CONCLUSIONES: El aumento significativo de consultas se debe a problemas sociales en la población, no al aumento de ninguna patología en especial. Impacta como problema clínico concreto la prevalencia de vaginosis bacteriana y Candida spp. Llama la atención, la nula incidencia de N. gonorrhoeae y la baja circulación de T. Vaginalis y C. trachomatis, en este tipo de población. La prevalencia de U. urealyticum y M. hominis es alta, pero su real participación en la patología genital de

  13. Problemas asociados al equilibrio en estructuras de membrana con bordes rígidos y cables

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    Viglialoro, G.

    2011-12-01

    asociado a un cable de borde lleva a una condición de frontera muy singular que dificulta un tanto el análisis. A partir de ello, caben dos enfoques complementarios, llamados problema directo y problema dual. Se definen y analizan ambos problemas de contorno, estudiando sus principales aspectos cualitativos. Asimismo, con el objetivo de obtener resultados prácticos, se propone un procedimiento general de resolución numérica para el problema directo.

  14. Factores de riesgo asociados con la enfermedad periodontal en niños

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    Joany Duque de Estrada Riverón

    2003-04-01

    Full Text Available Se realizó un estudio analítico del tipo casos y controles en el municipio de Colón, provincia de Matanzas, durante los cursos académicos 2000-2002, con el objetivo de caracterizar los principales factores de riesgo asociados con la enfermedad periodontal. Se investigó una población de 2 995 niños de 9, 12 y 15 años, de los cuales se tomó una muestra aleatoria aproximadamente del 50 % (P=0,50, los que se dividieron en 60 casos y 60 controles. Se consideraron como casos los niños portadores de la enfermedad y como controles los niños sanos. Se determinó que la higiene bucal fue nula en el 100 %, la infección microbiana se presentó en un alto porcentaje (46,70 %, la respiración bucal afectó al 28,30 % de los pacientes, las enfermedades sistémicas se observaron en el 35,00 %, el apiñamiento dentario en el 26,70 y las obturaciones defectuosas el 66,70 % de los casos.In order to characterize the main risk factors associated with the periodontal disease, an analytical case control study was carried out in the municipality of Colón, province of Matanzas, during the academic courses 2000-2002, in a population of 2 995 children aged 9, 12 and 15. A randomized sample of approximately 50 % (P=0.50 was taken. They were divided into 60 cases and 60 controls. Those children carriers of the disease were considered as cases, and the sound as controls. It was determined that oral hygiene was nil in 100 %. Microbial infection was observed in a high percentage (46.70 %. Respiration by the mouth affected 28.30 % of the cases. The systemic diseases were found in 35 %, tooth- crowding in 26.70 and defecient

  15. Factores asociados a mastitis en vacas de la microcuenca lechera del altiplano norte de Antioquia, Colombia

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    Nicolás Ramírez Vásquez

    2011-12-01

    Full Text Available Se efectuó un estudio de corte sobre la prevalencia de mastitis bovina en una muestra representativa de las granjas lecheras del altiplano norte de Antioquia, Colombia. Se evaluaron los resultados del California Mastitis Test (CMT, Recuento de Células Somáticas (RCS y cultivo bacteriológico de leche, y se analizaron los factores de riesgo asociados a mastitis bovina. El análisis estadístico de la información se efectuó por medio de estadística descriptiva, análisis de razón de prevalencias y regresión logística multinivel. Con la prueba de CMT se detectó un 20% de cuartos afectados con mastitis, la prevalencia de mastitis subclínica por vaca fue del 39,5% y la de mastitis clínica fue del 1,7%. Se efectuaron 648 cultivos de muestras de leche, de las cuales 23,9% fueron negativas, 34% positivas a Streptococcus agalactiae y 10,2% a Estafilococo coagulasa negativo. El análisis de regresión reveló que las vacas que tuvieron más de seis meses de lactancia presentaron una Odds Ratio (OR de 2,65 en comparación con las de un mes de lactancia (p < 0,05. Se halló un OR de 1,24 para la asociación de la edad y la mastitis (p < 0,05. Para el lavado de manos se encontró un OR de 0,36 en comparación con no hacerlo (p < 0,05. En conclusión, se halló una alta frecuencia de mastitis por vaca. El microorganismo más hallado fue el Streptococcus agalactiae. El trauma podría ser una causa importante de mastitis dado que no se observó crecimiento bacteriano en 23,9% de los cultivos de muestras de leche de cuartos con mastitis.

  16. Prevalencia de microorganismos asociados a secreción genital femenina, Argentina

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    Susana Di Bartolomeo

    2002-10-01

    Full Text Available OBJETIVO: Hay un aumento significativo de pacientes con Secreción Genital Femenina, en el Sector Público del gran Buenos Aires. Fue necesario actualizar la prevalencia de los microorganismos asociados a los efectos de revisar el apoyo necesario de laboratorio y ajustar las medidas de prevención y control. MÉTODOS: Se incorporan a este estudio, la totalidad de los casos atendidos (1997-1998: 84 adolescentes (15 a 19 años y 784 adultas (20 a 60 años sintomáticas. El protocolo incluye (secreción vaginal y endocervical detección de Neisseria gonorrhoeae, Streptococcus agalactiae, Trichomonas vaginalis, Candida spp y vaginosis bacteriana. Aplicando métodos específicos directos y cultivo, Chlamydia trachomatis (detección de antígeno, Ureaplasma urealitycum y Mycoplasma hominis (cultivos fueron estudiados en parte de la población total. RESULTADOS: El aumento de la demanda de consulta fue continuo desde 1997 y aumentó 2.10 veces del primero al último semestre de 1998. En las mujeres adultas se encontró: vaginosis bacteriana, 23,8%; Candida spp 17,8%; S. agalactiae 5,6%; T. vaginalis 2,4%. En 50,3% no se detecto ninguno. En adolescentes se detectó: vaginosis bacteriana, 17,8%; Candida spp 29,7%; S. agalactiae 3,6%, T. vaginalis 2,4%: En 46,4% de los casos el resultado fue negativo. En el grupo de mujeres adultas sintomáticas, no en la totalidad, se detectó: C. trachomatis (7/400 1,76%, U. urealyticum (209/340 61,4% y M. hominis (45/272 16,5%. CONCLUSIONES: El aumento significativo de consultas se debe a problemas sociales en la población, no al aumento de ninguna patología en especial. Impacta como problema clínico concreto la prevalencia de vaginosis bacteriana y Candida spp. Llama la atención, la nula incidencia de N. gonorrhoeae y la baja circulación de T. Vaginalis y C. trachomatis, en este tipo de población. La prevalencia de U. urealyticum y M. hominis es alta, pero su real participación en la patología genital de

  17. Ácaros (Arahcnida: Acari asociados a escarabajos pasálidos (Coleóptera: Passalidae de Colombia

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    José Orlando Combita Heredia

    2006-01-01

    Full Text Available Se determinaron taxonómicamente a nivel de familia y en algunos casos a género, los ácaros asociados a escarabajos de la familia Passalidae de Colombia. Se hallaron 23  morfoespecies de ácaros, se identificaron ocho géneros correspondientes a 11 familias, la gran mayoría pertenecen al suborden Mesostigmata, cohorte Monogynaspida; la familia Uropodidae fue la más predominante. El género Heterocheylus se encontró asociado exclusivamente al género Passalus. Todos los individuos revisados en este trabajo presentaron evidencias de una asociación forética con los pasálidos. Fueron detectadas para algunas morfoespecies y géneros una distribución específica sobre el cuerpo del escarabajo y una repartición de los microhábitats en las superficies de adhesión del pasálido. Se hace el primer registro para Colombia de las familias Diplogynidae y Anoetidae, se proporciona una clave ilustrada para familias de América con algunos comentarios sobre las familias presentes en Colombia y se aporta una colección de referencia.

  18. Efecto de riegos presurizados sobre propiedades físicas de un suelo bananero asociado Con Kudzu (Pueraria phaseoloides Benth

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    Ing. Pablo Ernesto Villa Guerrero

    2018-04-01

    Full Text Available Para evaluar el efecto de los riegos presurizados sobre suelos bananeros se seleccionaron cuatro bloques, uno de ellos influenciado por un sistema de riego subfoliar y otro influenciado por un sistema de riego suprafoliar, completándolo condos bloques asociados con Kudzu (Pueraria phaseoloides Benth de iguales sistemas de riego. El efecto de los sistemas de riego se evaluó sobre el perfil del suelo en estratos de 10cm hasta los 50 cm de profundidad, determinando en cada estratola densidad real, porcentaje de humedad, densidad aparente, resistencia a la penetración y porcentaje de porosidad, además del índice de estabilidad estructural y el de encostramiento. Los valores obtenidos indican que para ambos sistemas de riego la capa con más influencia fue la 10-20 cm y observándose un menor efecto en los bloques asociados con Kudzu, los cuales no tuvieron índices de formación de costras superficiales. Palabras clave: Sistemas de riego, porosidad, humedad del suelo, densidad aparente, banano.

  19. Respuestas psicofisiológicas ante estímulos asociados al tabaco: Diferencias entre fumadores y no fumadores

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    Carlos Gantiva

    2016-09-01

    Full Text Available Las respuestas emocionales y motivacionales son fundamentales para explicar el inicio y mantenimiento del consumo de tabaco; sin embargo, las diferencias en fumadores y no fumadores de las respuestas psicofisiológicas que sirven como marcadores neurofisiológicos de procesos emocionales y motivacionales presentan resultados contradictorios. El objetivo de esta investigación fue identificar las diferencias en las respuestas psicofisiológicas ante estímulos asociados al tabaco en fumadores y no fumadores. Para esto se registró el reflejo de sobresalto y la respuesta galvánica de la piel mientras observaban imágenes apetitivas, neutrales, aversivas y asociadas al tabaco. Los resultados muestran que los fumadores inhiben el reflejo de sobresalto ante las imágenes asociadas al tabaco de forma similar que ante las imágenes apetitivas; así mismo, se encontró en los fumadores una mayor inhibición del reflejo de sobresalto ante las imágenes de tabaco. No se encontraron diferencias en la respuesta galvánica de la piel. Estos resultados sugieren que los fumadores activan el sistema motivacional apetitivo ante los estímulos asociados al tabaco.

  20. Factores asociados a la infección tuberculosa latente en los contactos de pacientes afectados

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    Miquel Alsedà

    2004-04-01

    Full Text Available Fundamento: Una vez obtenidas unas cifras aceptables en la identificación y el tratamiento de los enfermos tuberculosos, se plantea una intervención para evitar la aparición de nuevos casos. Las personas con una infección tuberculosa latente (ITL reciente tienen un mayor riesgo de desarrollar una enfermedad tuberculosa. El objetivo de este estudio es evaluar la prevalencia de ITL y sus factores asociados en los contactos de pacientes tuberculosos. Métodos: Se estudiaron los contactos de estos pacientes examinados en el Centro de Prevención y Control de la Tuberculosis de Lleida en el período 1991-1997. Se recogieron factores asociados con el caso índice (demográficos, radiográficos, bacteriológicos y terapéuticos y el resultado de la prueba de la tuberculina en los contactos y sus datos demográficos. También se recogieron datos del caso índice relacionados con la infección por el VIH, el uso de drogas por vía parenteral y el consumo excesivo de alcohol. Como medida de asociación, se calcularon las odds ratio (OR crudas y ajustadas (ORa. Resultados: La prevalencia global de ITL en los contactos fue del 36,1% (780 de 2.161. En el análisis multivariante se detectó una mayor frecuencia de ITL en los contactos mayores de 14 años (ORa = 3,34; intervalo de confianza [IC] del 95%, 2,51-4,45, en los convivientes (ORa = 1,96; IC del 95%, 1,59-2,42, en los contactos de caso índice con una localización pulmonar de la enfermedad (ORa = 1,54; IC del 95%, 1,01-2,35, en los de caso índice con baciloscopia positiva en las muestras respiratorias (ORa = 1,51; IC del 95%, 1,15-1,99, en los de caso índice con patrón de cavitaciones en la radiografía de tórax (ORa = 1,27; IC del 95%, 1,01-1,61 y en los de casos índice con demora en el inicio del tratamiento (ORa = 1,31; IC del 95%, 1,05-1,62. Conclusiones: La prevalencia global de ITL en los contactos de enfermos tuberculosos es elevada. Entre los factores estudiados, la demora en el

  1. Complicaciones y costos asociados a la varicela en niños inmunocompetentes

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    Sáez-Llorens Xavier

    2002-01-01

    Full Text Available Objetivos. La varicela es una infección común de la infancia en países que no han incorporado la vacunación correspondiente en sus calendarios vacunales. Generalmente es benigna en niños inmunocompetentes y no necesita tratamiento. Los objetivos de este estudio consistieron en investigar la frecuencia y características de las complicaciones de la varicela que requieran tratamiento hospitalario en niños inmunocompetentes y el curso clínico de los hijos de madres con varicela perinatal. Además, se calculó el gasto hospitalario asociado a la varicela en los niños estudiados. Métodos. Estudio retrospectivo de los expedientes clínicos de niños con varicela ingresados en el Hospital del Niño de Panamá, de enero de 1991 a diciembre de 2000. Se analizaron el tipo de complicaciones, el curso clínico y los costos hospitalarios de los pacientes afectados por varicela. Resultados. De 5 203 niños atendidos en consultas externas, 568 (11% fueron hospitalizados. En el estudio se incluyeron 513 niños: 381 (74% con varicela adquirida en la comunidad, 92 (18% hijos de madres con varicela y 40 (8% con varicela nosocomial. Las complicaciones más frecuentes fueron las infecciones cutáneas y subcutáneas (45%, las infecciones respiratorias (25% y las alteraciones neurológicas (7%. Las complicaciones respiratorias y cutáneas ocurrieron a menor edad y en fases más tempranas de la varicela que las alteraciones neurológicas. Trece niños (2,5% fallecieron, con una letalidad del 8% para la varicela con complicaciones respiratorias y neurológicas y nula para las complicaciones cutáneas. Sesenta de los 92 (65% hijos de madres con varicela no desarrollaron la enfermedad y ninguno falleció. En cambio, 2 de los 32 neonatos (6% con varicela perinatal fallecieron. La duración media de la hospitalización fue de 8,9 (1 a 27 días. Se utilizó farmacoterapia parenteral en una gran proporción de los niños, especialmente antibióticos (54%, aciclovir

  2. Brote de legionelosis asociado a un balneario Legionella outbreak at a spa

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    E. Serrano Ibarbia

    2001-06-01

    Full Text Available En 1998 el inicio de la temporada de actividad de un balneario en Gipuzkoa coincidió con la detección de un brote de legionelosis asociado al mismo, lo cual condujo al cierre de la instalación y al estudio epidemiológico -casos y controles- y ambiental oportunos. Se definió como caso toda persona que durante su estancia en el balneario o durante los 10 días siguientes presentará neumonía o un cuadro febril compatible con fiebre de Pontiac.El estudio ambiental incluyó la inspección del balneario y entorno y muestreos de los sistemas sanitarios de agua y de los elementos de hidroterapia.De las 287 personas encuestadas de la Comunidad Autónoma Vasca, el 12.5% cumplían con la definición de caso; 9 casos presentaron neumonía y 26 fiebre de Pontiac. La curva epidémica se inició el 7 de mayo, alcanzando un pico los días 14 y 15 de mayo y finalizando el día 20. El riesgo de enfermar ajustado por edad, sexo y consumo de tabaco se asoció con la duración de la estancia en el balneario (OR=118.5, 95% I.C: 18.7-750.2 y con el uso de una piscina (OR=10.5, 95% I.C: 1.3-82.6. Se detecto L. pneumophila serogrupo1 en recuentos superiores a 103 ufc/l en diversos puntos de la red de hidroterapia y en la ducha de la habitación de uno de los enfermos. El análisis por electroforesis en campos pulsados de una muestra biológica y muestras ambientales permitió la confirmación genotípica. El establecimiento se abrió al público tras realizar un tratamiento de choque y comprobar que transcurridos 15 días no se detectó L. pneumophila en las muestras ambientales.The start of seasonal activity at a spa in Guipuzcoa coincided with the detection of an associated legionnaire outbreak in 1998. This led to the closure of the premises and to the carrying out of opportune environmental and epidemiological studies. The latter included case-control study. A case was defined as a person who, either during his stay or in a period of 10 days thereafter

  3. Factores asociados a la compresión lectora en estudiantes de noveno grado de Barranquilla

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    Mónica Paola Franco Montenegro

    2016-07-01

    Full Text Available El presente artículo es resultado de una investigación cuyo objetivo consistió en determinar la incidencia de los factores asociados al desarrollo de la comprensión lectora en estudiantes de noveno grado de la Institución Educativa Distrital Jesús Maestro Fe y Alegría de Barranquilla. Asumiendo que la comprensión lectora está presente en la vida como fuente de entendimiento y placer, esta investigación surge porque los docentes en aula han identificado que los estudiantes presentan dificultades en el proceso lector que pueden estar asociadas a factores académicos, socioculturales y personales. El diseño es de carácter Mixto (cualitativo-cuantitativo y las técnicas de recolección de información fueron: entrevista y encuestas con preguntas cerradas y abiertas. Los resultados evidenciaron que el 50% de los estudiantes poseen la habilidad para comprender lo que leen, pero su contexto familiar no acompaña los procesos y en lo escolar no hay ambientes que motiven la lectura. Lo anterior se evidencia en el desempeño escolar de los mismos. Ante este problema, la institución debe gestionar estrategias pedagógicas para fomentar procesos lectores en los que se integren las áreas del conocimiento, así como crear espacios para el desarrollo de la lectura y su comprensión. Abstract This article is the result of research and its main work objective is to determine the incidence of the factors associated with the development of Reading Comprehension for ninth grade students of School District Jesús Maestro Fe y Alegría of Barranquilla. Based on the fact that reading comprehension is present in life as a source of understanding and pleasure, because when learners read, they are generally motivated to think and respond with answers; this research arises because teachers in the classroom identify those students that have difficulties in the reading process, which in turn may be associated with academic, cultural and personal factors that

  4. Application of Optical Coherence Tomography and Contrast Sensitivity Test for Observing Fundus Changes of Patients With Pregnancy-Induced Hypertension Syndrome.

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    Wang, Zhixue; Zou, Yuanyuan; Li, Wenying; Wang, Xueyan; Zhang, Min; Wang, Wenying

    2015-11-01

    This study was aimed to investigate the fundus changes of patients with pregnancy-induced hypertension syndrome (PIHS) using optical coherence tomography (OCT) technology and contrast sensitivity (CS) tests.Ninety-eight patients with PIHS underwent routine eye examinations including vision correction, fundus examination, OCT, and CS tests. The CS test was performed at low, medium, and high frequency, respectively. Moreover, the difference in CS tests between 2 groups was analyzed by independent-samples T test. The Kruskal-Wallis rank sum test and linear regression model were used to detect the correlation of OCT with CS, respectively. Meanwhile Satterthwaite approximate T test was adopted for pairwise comparisons after nonparametric analysis of variance.The OCT test revealed that 56.76% of the examined eyes showed shallow retinal detachment in the macula lutea and around the optic disk. The differences in CS at each spatial frequency between the case and control group were statistically significant (P tests might be valuable methods in observing fundus changes for PIHS patients.

  5. The Nonmydriatic Fundus Camera in Diabetic Retinopathy Screening: A Cost-Effective Study with Evaluation for Future Large-Scale Application

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    Giuseppe Scarpa

    2016-01-01

    Full Text Available Aims. The study aimed to present the experience of a screening programme for early detection of diabetic retinopathy (DR using a nonmydriatic fundus camera, evaluating the feasibility in terms of validity, resources absorption, and future advantages of a potential application, in an Italian local health authority. Methods. Diabetic patients living in the town of Ponzano, Veneto Region (Northern Italy, were invited to be enrolled in the screening programme. The “no prevention strategy” with the inclusion of the estimation of blindness related costs was compared with screening costs in order to evaluate a future extensive and feasible implementation of the procedure, through a budget impact approach. Results. Out of 498 diabetic patients eligible, 80% was enrolled in the screening programme. 115 patients (34% were referred to an ophthalmologist and 9 cases required prompt treatment for either proliferative DR or macular edema. Based on the pilot data, it emerged that an extensive use of the investigated screening programme, within the Greater Treviso area, could prevent 6 cases of blindness every year, resulting in a saving of €271,543.32 (−13.71%. Conclusions. Fundus images obtained with a nonmydriatic fundus camera could be considered an effective, cost-sparing, and feasible screening tool for the early detection of DR, preventing blindness as a result of diabetes.

  6. Sensitivity and specificity of monochromatic photography of the ocular fundus in differentiating optic nerve head drusen and optic disc oedema: optic disc drusen and oedema.

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    Gili, Pablo; Flores-Rodríguez, Patricia; Yangüela, Julio; Orduña-Azcona, Javier; Martín-Ríos, María Dolores

    2013-03-01

    Evaluation of the efficacy of monochromatic photography of the ocular fundus in differentiating optic nerve head drusen (ONHD) and optic disc oedema (ODE). Sixty-six patients with ONHD, 31 patients with ODE and 70 healthy subjects were studied. Colour and monochromatic fundus photography with different filters (green, red and autofluorescence) were performed. The results were analysed blindly by two observers. The sensitivity, specificity and interobserver agreement (k) of each test were assessed. Colour photography offers 65.5 % sensitivity and 100 % specificity for the diagnosis of ONHD. Monochromatic photography improves sensitivity and specificity and provides similar results: green filter (71.20 % sensitivity, 96.70 % specificity), red filter (80.30 % sensitivity, 96.80 % specificity), and autofluorescence technique (87.8 % sensitivity, 100 % specificity). The interobserver agreement was good with all techniques used: autofluorescence (k = 0.957), green filter (k = 0.897), red filter (k = 0.818) and colour (k = 0.809). Monochromatic fundus photography permits ONHD and ODE to be differentiated, with good sensitivity and very high specificity. The best results were obtained with autofluorescence and red filter study.

  7. Efectos genotóxicos asociados a metales pesados en una población humana de la región de La Mojana, Colombia, 2013

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    Clelia Rosa Calao

    2015-08-01

    Conclusión. Estos resultados sugieren que el daño genético registrado en pobladores de la región de La Mojana, Colombia, puede estar asociado a la presencia de los metales estudiados en las muestras de sangre.

  8. FACTORES ASOCIADOS A SÍNDROME DE ASPIRACIÓN MECONIAL EN EL HOSPITAL JOSÉ CAYETANO HEREDIA PIURA-PERÚ

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    Nelson David Purizaca Rosillo

    2011-01-01

    Full Text Available Objetivo: Determinar los principales factores de riesgo en recién nacidos asociados a la presencia de síndrome de aspiración meconial (SAM. Métodos: Estudio de casos y controles realizado en el Hospital José Cayetano Heredia EsSALUD - Piura. La población estuvo conformada por el registro de las historias clínicas de los años 2009-2011. Se definió como caso a los recién nacidos con diagnóstico de SAM y como controles a los 3 recién nacidos siguientes inmediatos al caso que hayan presentado líquido amniótico meconial en el parto. Las variables consideradas fueron las características del líquido meconial, datos del recién nacido (género, peso al nacer, edad gestacional, apgar al minuto y frecuencia cardiaca, datos del parto(tipo de parto, presencia de patología obstétrica y datos de la madre(edad, paridad y grado de instrucción. Se utilizó el OR con un intervalo de confianza del 95% para la medición de riesgo, se aplicó la prueba de chi cuadrado. Para el análisis estadístico se utilizó el software SPSS 18.0. Resultados: Las variables con significancia estadística asociados a SAM fueron: presencia de líquido amniótico meconial espeso (OR=12, IC95% 3.91 - 36.83, Apgar 4 (OR=6.18, IC95% 1.34-28.48. Conclusión: Los factores de riesgo asociados a la presencia de SAM fueron: líquido meconial espeso, Apgar 4. Se recomienda un mayor registro de todos los datos no sólo del recién nacido, sino también del parto y la madre.

  9. Factores asociados a la no adherencia al tratamiento antirretroviral de gran actividad en adultos infectados con el VIH-sida

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    Óscar Alvis

    2009-12-01

    Full Text Available Introducción: La no adherencia al tratamiento antirretroviral de gran actividad (Targa es la principal causa de fracaso terapéutico. Objetivos: Determinar la prevalencia y los factores asociados a la no adherencia al Targa en adultos infectados con el VIH-sida. Diseño: Estudio transversal. Institución: Servicio de Infectología, Hospital Nacional Arzobispo Loayza. Participantes: Pacientes infectados con el VIH que se encontraban recibiendo tratamiento antirretroviral. Intervenciones: A pacientes infectados con el VIH que se encontraban recibiendo tratamiento antirretroviral en el hospital, se aplicó un cuestionario estructurado, elaborado en función a instrumentos que evalúan la adherencia y factores asociados. Para determinar la asociación, se empleó las pruebas de chi cuadrado y t de student, se estableció un nivel de significación estadística p<0,05, y para calcular el riesgo se utilizó el OR, con intervalos de confianza de 95%. Se realizó análisis de regresión logística. Principales medidas de resultados: No adherencia al tratamiento antirretroviral de gran actividad. Resultados: Se encuestó 465 personas; la edad promedio fue 36,8±9,1 años; 64,1% era varón. El 35,9% de los encuestados resultó ser no adherente. Los factores independientemente asociados a la no adherencia fueron: ser homosexual/bisexual (OR: 3,85, IC95% 1,98 a 7,51, tener una baja calidad de vida relacionada a la salud (OR: 6,22, IC95% 3,47 a 11,13, poco apoyo social (OR: 5,41, IC95% 3,17 a 9,22, no tener domicilio fijo (OR 3,34, IC95% 1,93 a 5,79, tener morbilidad psíquica (OR 2,93, IC95% 1,78 a 4,82 y tener mayor tiempo en tratamiento (OR 1,04, IC95% 1,02 a 1,07. Conclusiones: La prevalencia de no adherencia fue mayor a la reportada previamente en este mismo hospital, pero similar a la encontrada en diferentes estudios, pese a la heterogeneidad de los mismos. Los factores de tipo psicosocial fueron los que influyeron de forma más importante en la

  10. Prevalencia de tabaquismo durante el embarazo y factores asociados en Andalucía 2007-2012

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    Pedro M. Mateos-Vílchez

    2014-01-01

    Full Text Available Fundamentos: El tabaquismo durante la gestación constituye el principal problema prevenible de salud perinatal. El objetivo es establecer la prevalencia de tabaquismo de las mujeres gestantes en distintos momentos del embarazo así como explorar factores asociados al mismo. Métodos: Estudio transversal. La población diana fueron las mujeres cuyo control de embarazo se realizaba en centros de salud públicos. Muestra aleatoria representativa de 40 centros estratificados según número de embarazos. Participaron 1.813 mujeres seleccionadas en 3 muestras independientes (inicio y final del embarazo y posparto. La exposición se midió mediante cotinina en orina, autodeclaración y monóxido de carbono. Se registraron variables sociodemográficas, de tabaquismo y clínico-obstétricas. Se realizó una regresión logística para identificar los factores asociados al tabaquismo. Resultados: La prevalencia media fue 21,6%, menor al final del embarazo (15,6% y en el puerperio (16,7% y mayor en el principio del embarazo (30,3%. Las mujeres fumadoras diarias pasaron del 56,3% antes del embarazo al 14% al final (autodeclaración. El 21,8% de los abandonos se produjo antes del embarazo y el 23,6% cuando las mujeres supieron que estaban embarazadas. La ocultación del consumo fue 19,6% . Fueron factores asociados ser joven (OR: 0,956; IC: 0,92-0,99, estar expuesta al tabaco en el hogar (OR: 3,48; IC: 2,6-4,7, consumo pregestacional alto (6-10 OR: 13,1 IC: 3-56,9; >10 OR: 25,1 IC: 5,8-109,6, mayor edad gestacional en la medición (al final OR: 0,5 IC: 0,4-0,8; posparto inmediato OR: 0,4 IC: 0,3-0,6 y menor nivel de estudios (sin estudios y primer grado comparadas con universitarias OR: 1,98; IC: 1,22-3,22. Conclusiones: El perfil de la mujer gestante fumadora es el de una mujer joven con bajo nivel educativo, expuesta al humo de tabaco en el hogar y con alto consumo pregestacional.

  11. Grading of Age-Related Macular Degeneration: Comparison between Color Fundus Photography, Fluorescein Angiography, and Spectral Domain Optical Coherence Tomography

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    Nils F. Mokwa

    2013-01-01

    Full Text Available Purpose. To compare color fundus photography (FP, fluorescein angiography (FA, and spectral domain optical coherence tomography (SDOCT for the detection of age-related macular degeneration (AMD, choroidal neovascularisation (CNV, and CNV activity. Methods. FPs, FAs, and SDOCT volume scans from 120 eyes of 66 AMD and control patients were randomly collected. Control eyes were required to show no AMD, but other retinal pathology was allowed. The presence of drusen, pigmentary changes, CNV, and signs for CNV activity was independently analyzed for all imaging modalities. Results. AMD was diagnosed based on FP in 75 eyes. SDOCT and FA showed sensitivity (specificity of 89% (76% and 92% (82%, respectively. CNV was present on FA in 68 eyes. Sensitivity (specificity was 78% (100% for FP and 94% (98% for SDOCT. CNV activity was detected by SDOCT or FA in 60 eyes with an agreement in 46 eyes. Sensitivity was 88% for SDOCT and 88% for FA. FP showed sensitivity of 38% and specificity of 98%. Conclusions. CNV lesions and activity may be missed by FP alone, but FP may help identifying drusen and pigmentary changes. SDOCT is highly sensitive for the detection of AMD, CNV, and CNV activity; however, it cannot fully replace FA.

  12. Characteristic appearances of fundus autofluorescence in treatment-naive and active polypoidal choroidal vasculopathy: a retrospective study of 170 patients.

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    Zhao, Xinyu; Xia, Song; Chen, Youxin

    2018-06-01

    To investigate the characteristic appearances of fundus autofluorescence (FAF) in patients with treatment-naive and active polypoidal choroidal vasculopathy (PCV). Cases with the diagnosis of treatment-naive and active PCV from November 2012 to May 2017 at Peking Union Medical College Hospital were retrospectively reviewed. All patients underwent comprehensive ophthalmologic examination. Autofluorescence (AF) findings were described at the retinal sites of the corresponding lesions identified and diagnosed using indocyanine green angiography and spectral-domain optical coherence tomography. One hundred seventy patients with 192 affected eyes were included. The logMAR BCVA of the patients were 0.53 ± 0.28. The six AF patterns of 243 polypoidal lesions were confluent hypo-AF with hyper-AF ring (49.8%), confluent hypo-AF (22.6%), hyper-AF with hypo-AF ring (3.7%), granular hypo-AF (7.0%), blocked hypo-AF due to hemorrhage (8.6%), and polyps without apparent AF changes (8.2%). For 146 branching vascular networks (BVNs), 97.3% were granular hypo-AF, and others were blocked hypo-AF due to hemorrhage. In eyes with treatment-naive and active PCV, the polypoidal lesions and BVNs induce characteristic FAF changes. FAF images provide reliable adjunct reference for the diagnosis of PCV.

  13. A new unified framework for the early detection of the progression to diabetic retinopathy from fundus images.

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    Leontidis, Georgios

    2017-11-01

    Human retina is a diverse and important tissue, vastly studied for various retinal and other diseases. Diabetic retinopathy (DR), a leading cause of blindness, is one of them. This work proposes a novel and complete framework for the accurate and robust extraction and analysis of a series of retinal vascular geometric features. It focuses on studying the registered bifurcations in successive years of progression from diabetes (no DR) to DR, in order to identify the vascular alterations. Retinal fundus images are utilised, and multiple experimental designs are employed. The framework includes various steps, such as image registration and segmentation, extraction of features, statistical analysis and classification models. Linear mixed models are utilised for making the statistical inferences, alongside the elastic-net logistic regression, boruta algorithm, and regularised random forests for the feature selection and classification phases, in order to evaluate the discriminative potential of the investigated features and also build classification models. A number of geometric features, such as the central retinal artery and vein equivalents, are found to differ significantly across the experiments and also have good discriminative potential. The classification systems yield promising results with the area under the curve values ranging from 0.821 to 0.968, across the four different investigated combinations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Factores asociados al pie diabético en pacientes ambulatorios. Centro de Diabetes Cardiovascular del Caribe. Barranquilla (Colombia

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    Mildred Rosales Amarís

    2012-01-01

    respectivamente, la neuropatía (OR = 10.14; p = 0.00 y la deformidad de los pies (OR = 10.02; p = 0.00 se asociaron significativamente al pie diabético. Se encontró como factor protector el autocuidado (OR = 0.21; p = 0.00000 y la educación relacionada con el control de factores de riesgo para la diabetes (OR = 0.32; p = 0.00007. Conclusión: La macroangiopatía, la microangiopatía, la neuropatía y la deformidad en los pies se comportaron como factores asociados a la presencia del pie diabético. El autocuidado contribuyó a la prevención del mismo.

  15. Factores resilientes asociados al rendimiento académico en estudiantes pertenecientes a la Universidad de Sucre (Colombia

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    Sonia Carolina Peralta Díaz

    2006-01-01

    Full Text Available El objetivo de la investigación fue determinar si existen factores resilientes asociados al rendimiento académico en una muestra de estudiantes universitarios. Dicha muestra estuvo compuesta por 345 estudiantes, distribuidos en 2 grupos, bajo rendimiento y alto rendimiento, entre los 16 y 38 años de edad. El instrumento utilizado fue el cuestionario de resiliencia para estudiantes universitarios (cre-u. Los resultados, después de aplicar el modelo estadístico de regresión logística binaria (Oportunidad Relativa, indican que existen diferencias estadísticamente significativas de los factores resilientes entre los estudiantes con alto y bajo rendimiento académico, y este último grupo es el que se encuentra en mayor riesgo debido a que existen menos factores que se asocian a él.

  16. Santa Cristina III. Arte rupestre asociado a una estructura megalítica en el País Vasco

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    Antxoka MARTÍNEZ VELASCO

    2009-12-01

    Full Text Available RESUMEN: Durante la primera campaña de prospección visual en el Parque Natural de Valderejo (Álava fue hallada una estructura megalítica que denominamos Santa Cristina III. En el techo de la cámara de esta estructura se conservan varias puntuaciones en rojo. Se trata del primer ejemplo de arte asociado a una estructura megalítica en el País Vasco. En este trabajo se presentan los primeros datos para su estudio e interpretación.ABSTRACT: During de first compaign of visual prospecting in the Natural Park of Valderejo (Álava it was discovered a megalithic structure, called Santa Cristina III. There is several red marcs in the room's ceiling of this structure. It's the first example of associated art to megalithic structure in the Basque Country. In this article we are presenting the main facts to value and understand this structure.

  17. Factores asociados a la colonización por Streptococcus del grupo B en mujeres embarazadas de Los Altos, Chiapas

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    Ocampo-Torres Moisés

    2000-01-01

    Full Text Available OBJETIVO: Estimar la prevalencia de colonización por Streptococcus del grupo B (SGB en mujeres embarazadas de Los Altos, Chiapas, y analizar factores asociados a la misma. MATERIAL Y MÉTODOS: Es un estudio transversal realizado de febrero a septiembre de 1999 en tres hospitales públicos de segundo nivel en San Cristóbal de las Casas, Chiapas. A 910 mujeres que acudieron para atención de parto a dichos hospitales, se les tomaron muestras (vaginal y perianal para detección de SGB por cultivo e identificación de grupo y serotipo mediante aglutinación en látex. El análisis de factores asociados a la colonización se realizó medianteji² y modelos log-lineales. RESULTADOS: La colonización por SGB fue de 8.6% (IC 95% 6.8 - 10.5. Las mujeres con mayor probabilidad de colonización fueron las de > o = 5 embarazos, residentes de municipios marginados, de ocupación diferente al hogar y con jefe/jefa de familia agrícola (26.8%, RM= 7.25, IC 95% 1.83 - 28.67. CONCLUSIONES: Es necesario que las acciones para la prevención y control de infección por SGB se dirijan principalmente a la población de mayor riesgo de colonización en el área de estudio, con el fin de disminuir la transmisión perinatal de SGB.

  18. Factores asociados con la irregularidad de la ingesta de Dapsona en pacientes con lepra: Dapsona en pacientes con lepra

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    Luis Carlos Orozco Vargas

    2013-04-01

    Full Text Available Introducción: Conocer los factores asociados al cumplimiento del tratamiento en pacientes con lepra, es muy importante para prevenir la resistencia del Mycobacterium leprae y garantizar la cura bacteriológica de estas personas. La prueba de orina para Dapsona, presente en el régimen autoadministrado, es un método sencillo para establecer la regularidad del tratamiento. Objetivo: Explorar los factores asociados a la irregularidad de la ingesta del tratamiento antileproso. Métodos: Estudio de corte transversal de los enfermos que recibieron tratamiento antileproso en un centro dermatológico. La irregularidad se estableció con la prueba de dapsonuria. Se consideró irregular el que presentó la prueba negativa. Las variables sospechosas de influir en la irregularidad se analizaron con regresión logística exacta. Resultados: En el modelo final del análisis multivariado se encontraron cinco variables asociadas, entre éstas sobresalen como factores de riesgo, la ausencia de discapacidad, OR 28.56 (IC90% 1.2-2.1 y la entrega de tratamiento para tiempos mayores a un mes, por cada mes OR 3.41 (IC90% 1.4-9.2 y como factor protector, la aceptación familiar de la enfermedad OR 0.008 (IC90% 0.001-0.24. Conclusión: Aunque es posible que el pequeño tamaño de muestra no haya permitido detectar algunos factores de riesgo informados en otras investigaciones, la mayoría de esos estudios no han realizado análisis multivariado por lo cual es posible que muchos de los factores informados en la literatura no tengan importancia. Salud UIS 2013; 45 (1: 7-14

  19. Sensitivity and specificity of automated analysis of single-field non-mydriatic fundus photographs by Bosch DR Algorithm-Comparison with mydriatic fundus photography (ETDRS for screening in undiagnosed diabetic retinopathy.

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    Pritam Bawankar

    Full Text Available Diabetic retinopathy (DR is a leading cause of blindness among working-age adults. Early diagnosis through effective screening programs is likely to improve vision outcomes. The ETDRS seven-standard-field 35-mm stereoscopic color retinal imaging (ETDRS of the dilated eye is elaborate and requires mydriasis, and is unsuitable for screening. We evaluated an image analysis application for the automated diagnosis of DR from non-mydriatic single-field images. Patients suffering from diabetes for at least 5 years were included if they were 18 years or older. Patients already diagnosed with DR were excluded. Physiologic mydriasis was achieved by placing the subjects in a dark room. Images were captured using a Bosch Mobile Eye Care fundus camera. The images were analyzed by the Retinal Imaging Bosch DR Algorithm for the diagnosis of DR. All subjects also subsequently underwent pharmacological mydriasis and ETDRS imaging. Non-mydriatic and mydriatic images were read by ophthalmologists. The ETDRS readings were used as the gold standard for calculating the sensitivity and specificity for the software. 564 consecutive subjects (1128 eyes were recruited from six centers in India. Each subject was evaluated at a single outpatient visit. Forty-four of 1128 images (3.9% could not be read by the algorithm, and were categorized as inconclusive. In four subjects, neither eye provided an acceptable image: these four subjects were excluded from the analysis. This left 560 subjects for analysis (1084 eyes. The algorithm correctly diagnosed 531 of 560 cases. The sensitivity, specificity, and positive and negative predictive values were 91%, 97%, 94%, and 95% respectively. The Bosch DR Algorithm shows favorable sensitivity and specificity in diagnosing DR from non-mydriatic images, and can greatly simplify screening for DR. This also has major implications for telemedicine in the use of screening for retinopathy in patients with diabetes mellitus.

  20. Development and Validation of a Deep Learning Algorithm for Detection of Diabetic Retinopathy in Retinal Fundus Photographs.

    Science.gov (United States)

    Gulshan, Varun; Peng, Lily; Coram, Marc; Stumpe, Martin C; Wu, Derek; Narayanaswamy, Arunachalam; Venugopalan, Subhashini; Widner, Kasumi; Madams, Tom; Cuadros, Jorge; Kim, Ramasamy; Raman, Rajiv; Nelson, Philip C; Mega, Jessica L; Webster, Dale R

    2016-12-13

    Deep learning is a family of computational methods that allow an algorithm to program itself by learning from a large set of examples that demonstrate the desired behavior, removing the need to specify rules explicitly. Application of these methods to medical imaging requires further assessment and validation. To apply deep learning to create an algorithm for automated detection of diabetic retinopathy and diabetic macular edema in retinal fundus photographs. A specific type of neural network optimized for image classification called a deep convolutional neural network was trained using a retrospective development data set of 128 175 retinal images, which were graded 3 to 7 times for diabetic retinopathy, diabetic macular edema, and image gradability by a panel of 54 US licensed ophthalmologists and ophthalmology senior residents between May and December 2015. The resultant algorithm was validated in January and February 2016 using 2 separate data sets, both graded by at least 7 US board-certified ophthalmologists with high intragrader consistency. Deep learning-trained algorithm. The sensitivity and specificity of the algorithm for detecting referable diabetic retinopathy (RDR), defined as moderate and worse diabetic retinopathy, referable diabetic macular edema, or both, were generated based on the reference standard of the majority decision of the ophthalmologist panel. The algorithm was evaluated at 2 operating points selected from the development set, one selected for high specificity and another for high sensitivity. The EyePACS-1 data set consisted of 9963 images from 4997 patients (mean age, 54.4 years; 62.2% women; prevalence of RDR, 683/8878 fully gradable images [7.8%]); the Messidor-2 data set had 1748 images from 874 patients (mean age, 57.6 years; 42.6% women; prevalence of RDR, 254/1745 fully gradable images [14.6%]). For detecting RDR, the algorithm had an area under the receiver operating curve of 0.991 (95% CI, 0.988-0.993) for EyePACS-1 and 0

  1. Compact Laser Doppler Flowmeter (LDF Fundus Camera for the Assessment of Retinal Blood Perfusion in Small Animals.

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    Marielle Mentek

    Full Text Available Noninvasive techniques for ocular blood perfusion assessment are of crucial importance for exploring microvascular alterations related to systemic and ocular diseases. However, few techniques adapted to rodents are available and most are invasive or not specifically focused on the optic nerve head (ONH, choroid or retinal circulation. Here we present the results obtained with a new rodent-adapted compact fundus camera based on laser Doppler flowmetry (LDF.A confocal miniature flowmeter was fixed to a specially designed 3D rotating mechanical arm and adjusted on a rodent stereotaxic table in order to accurately point the laser beam at the retinal region of interest. The linearity of the LDF measurements was assessed using a rotating Teflon wheel and a flow of microspheres in a glass capillary. In vivo reproducibility was assessed in Wistar rats with repeated measurements (inter-session and inter-day of retinal arteries and ONH blood velocity in six and ten rats, respectively. These parameters were also recorded during an acute intraocular pressure increase to 150 mmHg and after heart arrest (n = 5 rats.The perfusion measurements showed perfect linearity between LDF velocity and Teflon wheel or microsphere speed. Intraclass correlation coefficients for retinal arteries and ONH velocity (0.82 and 0.86, respectively indicated strong inter-session repeatability and stability. Inter-day reproducibility was good (0.79 and 0.7, respectively. Upon ocular blood flow cessation, the retinal artery velocity signal substantially decreased, whereas the ONH signal did not significantly vary, suggesting that it could mostly be attributed to tissue light scattering.We have demonstrated that, while not adapted for ONH blood perfusion assessment, this device allows pertinent, stable and repeatable measurements of retinal blood perfusion in rats.

  2. Evaluation of Two Systems for Fundus-Controlled Scotopic and Mesopic Perimetry in Eye with Age-Related Macular Degeneration.

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    Steinberg, Julia S; Saßmannshausen, Marlene; Pfau, Maximilian; Fleckenstein, Monika; Finger, Robert P; Holz, Frank G; Schmitz-Valckenberg, Steffen

    2017-07-01

    The purpose of this study was to evaluate and compare the MP-1S (Nidek Technologies, Padova, Italy) and the S-MAIA (CenterVue, Padova, Italy) for mesopic and scotopic fundus-controlled perimetry (FCP) in age-related macular degeneration (AMD). Eleven eyes from 11 patients underwent mesopic and, after 30 minutes of dark adaptation, scotopic (MP-1S: Goldmann V, 200 ms, background luminance 0.0032 cd/m 2 ; S-MAIA: Goldman III, 200 ms, background luminance grid of 56 stimulus points covering 16° of the central macula was used. Examination time, fixation stability, and threshold values were analyzed. The upper end of the dynamic range (≤4 dB of lowest threshold) was frequently reached by the MP-1S for mesopic testing (median 34 of 56 stimuli), while threshold values within the lower 4 dB of the dynamic range were occasionally found with the S-MAIA for scotopic testing (median 3 for cyan, median 2 for red). After correction of the stimulus intensity for the S-MAIA results, the median difference for all stimuli between both devices for mesopic testing was -2.0 dB (interquartile range [-4;0], range -14 to 6). The results indicate that robust testing of mesopic and scotopic function is feasible with both devices in patients with AMD, although both devices are susceptible to floor and ceiling effects. The interpretation and particularly the comparison of both scotopic and mesopic FCP results between the MP-1S and the S-MAIA in AMD eyes need to consider variable susceptibility of floor and ceiling effects. Further software updates are desirable as FCP captures visual functional loss that is not noted with best-corrected central visual acuity and is important for clinical trials in AMD.

  3. Telemedicine for a General Screening of Retinal Disease Using Nonmydriatic Fundus Cameras in Optometry Centers: Three-Year Results.

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    Zapata, Miguel A; Arcos, Gabriel; Fonollosa, Alex; Abraldes, Maximino; Oleñik, Andrea; Gutierrez, Estanislao; Garcia-Arumi, Jose

    2017-01-01

    Describe the first 3 years of highly specialized retinal screening through a web platform using a retinologists' network for image reading. All patients who came to centers in the network and consented to fundus photography were included. Images were evaluated by ophthalmologists. We describe number of patients, age, visual acuity, retinal abnormalities, medical recommendations, and factors associated with abnormal retinographies. Fifty thousand three hundred eighty-four patients were included; mean age 52.3 years (range 3-99). Mean visual acuity 20/25. Of the total cohort, 75% had normal retinographies, 22% had abnormalities, 1% referred acute floaters, 1% referred acute symptoms with normal retinography, and 1% could not be assessed. Ophthalmological referral was recommended in 12,634 patients: 9% urgent visit, 11% preferential (2-3 weeks), and 80% an ordinary visit. Age-related maculopathy signs were the most common abnormalities (2,456 patients, 4.8%). Epiretinal membrane was the second (764 cases, 1.5%). Diabetic retinopathy was suspected in 543 patients (1%), and nevi in 358 patients (0.7%). Patients older than 50 years had significantly more retinal abnormalities (31.5%) than younger ones (11.1%) (p < 0.0001; odds ratio [OR] 2.47; confidence interval [CI] 2.37-2.57). Patients with almost one eye with a myopic defect greater than -5 spherical equivalent had a higher risk of presenting abnormalities (p < 0.001; OR 1.04; CI 1.03-1.05). A high rate of asymptomatic retinal abnormalities was detected in this general screening, justifying this practice. Many patients who visit optometrists in Spain are unaware that they would benefit from ophthalmological monitoring. The ophthalmic community should lead initiatives of the type presented to preserve and guarantee quality standards.

  4. Myosin Va Plays a Role in Nitrergic Smooth Muscle Relaxation in Gastric Fundus and Corpora Cavernosa of Penis

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    Carew, Josephine A.; Goyal, Raj K.; Sullivan, Maryrose P.

    2014-01-01

    The intracellular motor protein myosin Va is involved in nitrergic neurotransmission possibly by trafficking of neuronal nitric oxide synthase (nNOS) within the nerve terminals. In this study, we examined the role of myosin Va in the stomach and penis, proto-typical smooth muscle organs in which nitric oxide (NO) mediated relaxation is critical for function. We used confocal microscopy and co-immunoprecipitation of tissue from the gastric fundus (GF) and penile corpus cavernosum (CCP) to localize myosin Va with nNOS and demonstrate their molecular interaction. We utilized in vitro mechanical studies to test whether smooth muscle relaxations during nitrergic neuromuscular neurotransmission is altered in DBA (dilute, brown, non-agouti) mice which lack functional myosin Va. Myosin Va was localized in nNOS-positive nerve terminals and was co-immunoprecipitated with nNOS in both GF and CCP. In comparison to C57BL/6J wild type (WT) mice, electrical field stimulation (EFS) of precontracted smooth muscles of GF and CCP from DBA animals showed significant impairment of nitrergic relaxation. An NO donor, Sodium nitroprusside (SNP), caused comparable levels of relaxation in smooth muscles of WT and DBA mice. These normal postjunctional responses to SNP in DBA tissues suggest that impairment of smooth muscle relaxation resulted from inhibition of NO synthesis in prejunctional nerve terminals. Our results suggest that normal physiological processes of relaxation of gastric and cavernosal smooth muscles that facilitate food accommodation and penile erection, respectively, may be disrupted under conditions of myosin Va deficiency, resulting in complications like gastroparesis and erectile dysfunction. PMID:24516539

  5. Possible role for fundus autofluorescence as a predictive factor for visual acuity recovery after epiretinal membrane surgery.

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    Brito, Pedro N; Gomes, Nuno L; Vieira, Marco P; Faria, Pedro A; Fernandes, Augusto V; Rocha-Sousa, Amândio; Falcão-Reis, Fernando

    2014-02-01

    To study the potential association between fundus autofluorescence, spectral-domain optical coherence tomography, and visual acuity in patients undergoing surgery because of epiretinal membranes. Prospective, interventional case series including 26 patients submitted to vitrectomy because of symptomatic epiretinal membranes. Preoperative evaluation consisted of a complete ophthalmologic examination, autofluorescence, and spectral-domain optical coherence tomography. Studied variables included foveal autofluorescence (fov.AF), photoreceptor inner segment/outer segment (IS/OS) junction line integrity, external limiting membrane integrity, central foveal thickness, and foveal morphology. All examinations were repeated at the first, third, and sixth postoperative months. The main outcome measures were logarithm of minimal angle resolution visual acuity, fov.AF integrity, and IS/OS integrity. All cases showing a continuous IS/OS line had an intact fov.AF, whereas patients with IS/OS disruption could have either an increased area of foveal hypoautofluorescence or an intact fov.AF, with the latter being associated with IS/OS integrity recovery in follow-up spectral-domain optical coherence tomography imaging. The only preoperative variables presenting a significant correlation with final visual acuity were baseline visual acuity (P = 0.047) and fov.AF grade (P = 0.023). Recovery of IS/OS line integrity after surgery, in patients with preoperative IS/OS disruption and normal fov.AF, can be explained by the presence of a functional retinal pigment epithelium-photoreceptor complex, supporting normal photoreceptor activity. Autofluorescence imaging provides a functional component to the study of epiretinal membranes, complementing the structural information obtained with optical coherence tomography.

  6. Quantitative fundus autofluorescence in mice: correlation with HPLC quantitation of RPE lipofuscin and measurement of retina outer nuclear layer thickness.

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    Sparrow, Janet R; Blonska, Anna; Flynn, Erin; Duncker, Tobias; Greenberg, Jonathan P; Secondi, Roberta; Ueda, Keiko; Delori, François C

    2013-04-17

    Our study was conducted to establish procedures and protocols for quantitative autofluorescence (qAF) measurements in mice, and to report changes in qAF, A2E bisretinoid concentration, and outer nuclear layer (ONL) thickness in mice of different genotypes and age. Fundus autofluorescence (AF) images (55° lens, 488 nm excitation) were acquired in albino Abca4(-/-), Abca4(+/-), and Abca4(+/+) mice (ages 2-12 months) with a confocal scanning laser ophthalmoscope (cSLO). Gray levels (GLs) in each image were calibrated to an internal fluorescence reference. The bisretinoid A2E was measured by quantitative high performance liquid chromatography (HPLC). Histometric analysis of ONL thicknesses was performed. The Bland-Altman coefficient of repeatability (95% confidence interval) was ±18% for between-session qAF measurements. Mean qAF values increased with age (2-12 months) in all groups of mice. qAF was approximately 2-fold higher in Abca4(-/-) mice than in Abca4(+/+) mice and approximately 20% higher in heterozygous mice. HPLC measurements of the lipofuscin fluorophore A2E also revealed age-associated increases, and the fold difference between Abca4(-/-) and wild-type mice was more pronounced (approximately 3-4-fold) than measurable by qAF. Moreover, A2E levels declined after 8 months of age, a change not observed with qAF. The decline in A2E levels in the Abca4(-/-) mice corresponded to reduced photoreceptor cell viability as reflected in ONL thinning beginning at 8 months of age. The qAF method enables measurement of in vivo lipofuscin and the detection of genotype and age-associated differences. The use of this approach has the potential to aid in understanding retinal disease processes and will facilitate preclinical studies.

  7. Correlation of increased fundus autofluorescence signals at closed macula with visual prognosis after successful macular hole surgery.

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    Shiragami, Chieko; Shiraga, Fumio; Nitta, Eri; Fukuda, Kouki; Yamaji, Hidetaka

    2012-02-01

    To study the significance of the increased fundus autofluorescence (FAF) signals at closed macula with spectral-domain optical coherence tomography and visual prognosis after successful surgery in eyes with idiopathic full-thickness macular holes (MHs). Seventy-eight eyes of 78 consecutive patients with full-thickness MHs underwent successful standard vitrectomy, with internal limiting membrane peeling and followed by 10% sulfur hexafluoride gas injection. Simultaneous FAF and optical coherence tomography images were recorded at 10 days, and 1, 3, and 6 months postoperatively, using a combined spectral-domain optical coherence tomography-fluorescein angiography device (Spectralis™/HRA Heidelberg Retina Angiograph 2). The appearance of increased FAF in the macula postoperatively and the relationship of FAF and optical coherence tomography findings to best-corrected visual acuity were examined. Stage 2, 3, and 4 MHs were present in 31, 29, and 18 eyes, respectively. The median patient age was 66 years, with a range of 54 to 79 years. In all patients, the MHs were successfully closed, and the preoperative increased FAF corresponding to MH disappeared 10 days after surgery. In 36 eyes (46.2%), however, hyperautofluorescence again appeared in the macular area 1 month postoperatively. This hyperautofluorescence was significantly associated with the recovery of the external limiting membrane lines at the fovea 1 month after surgery (P = 0.001, multiple logistic regression analysis). Also, this recovery of the external limiting membrane lines 1 month postoperatively was significantly associated with the recovery of photoreceptor inner and outer segment junction line 3 months postoperatively at the fovea (P macula 1 month postoperatively, the recovery of the photoreceptor inner and outer segment lines at the fovea 3 months postoperatively, and preoperative good visual acuity (P macula 1 month after successful MH surgery. This hyperautofluorescence could be a sign of good

  8. Hyperosmolarity response of ocular standing potential as a clinical test for retinal pigment epithelium activity. Chorioretinal dystrophies.

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    Yonemura, D; Kawasaki, K; Madachi-Yamamoto, S

    1984-05-30

    The hyperosmolarity response of the standing potential was recorded in retinitis pigmentosa (20 eyes), central (pericentral) retinitis pigmentosa (4 eyes), pigmented paravenous retinochoroidal atrophy (2 eyes), fundus albipunctatus (8 eyes), and Stargardt's disease (or fundus flavimaculatus) (14 eyes). The light peak/dark trough ratio (the L/D ratio) and the Diamox response were also determined. The hyperosmolarity response was greatly suppressed (less than M-4SD; M and SD indicate respectively the mean and the standard deviation in normal control subjects) in all examined eyes with retinitis pigmentosa (20 eyes) including retinitis pigmentosa sine pigmento (8 eyes), central (pericentral) retinitis pigmentosa (4 eyes), and pigmented paravenous retinochoroidal atrophy (2 eyes). The L/D ratio was larger than 1.26 (M-2.5 SD) in the half of the eyes with the above-described diseases. The hyperosmolarity response was abnormal (less than M-2 SD) in 4 of 8 eyes with fundus albipunctatus. The L/D ratio was normal in all 8 eyes. The hyperosmolarity response was abnormal (less than M-2 SD) in all 14 eyes with Stargardt's disease or fundus flavimaculatus. The L/D ratio was abnormal in 5 of these 14 eyes. The hyperosmolarity response was more frequently abnormal than the L/D ratio in the chorioretinal dystrophies mentioned above, and hence is useful particularly for early diagnosis of these disorders.

  9. Retinal pigment epithelial changes in chronic Vogt-Koyanagi-Harada disease: fundus autofluorescence and spectral domain-optical coherence tomography findings.

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    Vasconcelos-Santos, Daniel V; Sohn, Elliott H; Sadda, Srinivas; Rao, Narsing A

    2010-01-01

    The purpose of this study was to determine whether fundus autofluorescence (FAF) and spectral domain-optical coherence tomography (SD-OCT) imaging allow better assessment of retinal pigment epithelium and the outer retina in subjects with chronic Vogt-Koyanagi-Harada disease compared with examination and angiography alone. A cross-sectional analysis of a series of seven consecutive patients with chronic Vogt-Koyanagi-Harada disease undergoing FAF and SD-OCT was conducted. Chronic disease was defined as duration of intraocular inflammation >3 months. Color fundus photographs were correlated to FAF and SD-OCT images. The images were later correlated to fluorescein angiography and indocyanine green angiography. All patients had sunset glow fundus, which resulted in no apparent corresponding abnormality on FAF or SD-OCT. Lesions with decreased autofluorescence signal were observed in 11 eyes (85%), being associated with loss of the retinal pigment epithelium and involvement of the outer retina on SD-OCT. In 5 eyes (38%), some of these lesions were very subtle on clinical examination but easily detected by FAF. Lesions with increased autofluorescence signal were seen in 8 eyes (61.5%), showing variable involvement of the outer retina on SD-OCT and corresponding clinically to areas of retinal pigment epithelium proliferation and cystoid macular edema. Combined use of FAF and SD-OCT imaging allowed noninvasive delineation of retinal pigment epithelium/outer retina changes in patients with chronic Vogt-Koyanagi-Harada disease, which were consistent with previous histopathologic reports. Some of these changes were not apparent on clinical examination.

  10. The Photosensitivity of Rhodopsin Bleaching and Light-Induced Increases of Fundus Reflectance in Mice Measured In Vivo With Scanning Laser Ophthalmoscopy

    Science.gov (United States)

    Zhang, Pengfei; Goswami, Mayank; Zawadzki, Robert J.; Pugh, Edward N.

    2016-01-01

    Purpose To quantify bleaching-induced changes in fundus reflectance in the mouse retina. Methods Light reflected from the fundus of albino (Balb/c) and pigmented (C57Bl/6J) mice was measured with a multichannel scanning laser ophthalmoscopy optical coherence tomography (SLO-OCT) optical system. Serial scanning of small retinal regions was used for bleaching rhodopsin and measuring reflectance changes. Results Serial scanning generated a saturating reflectance increase centered at 501 nm with a photosensitivity of 1.4 × 10−8 per molecule μm2 in both strains, 2-fold higher than expected were irradiance at the rod outer segment base equal to that at the retinal surface. The action spectrum of the reflectance increase corresponds to the absorption spectrum of mouse rhodopsin in situ. Spectra obtained before and after bleaching were fitted with a model of fundus reflectance, quantifying contributions from loss of rhodopsin absorption with bleaching, absorption by oxygenated hemoglobin (HbO2) in the choroid (Balb/c), and absorption by melanin (C57Bl/6J). Both mouse strains exhibited light-induced broadband reflectance changes explained as bleaching-induced reflectivity increases at photoreceptor inner segment/outer segment (IS/OS) junctions and OS tips. Conclusions The elevated photosensitivity of rhodopsin bleaching in vivo is explained by waveguide condensing of light in propagation from rod inner segment (RIS) to rod outer segment (ROS). The similar photosensitivity of rhodopsin in the two strains reveals that little light backscattered from the sclera can enter the ROS. The bleaching-induced increases in reflectance at the IS/OS junctions and OS tips resemble results previously reported in human cones, but are ascribed to rods due to their 30/1 predominance over cones in mice and to the relatively minor amount of cone M-opsin in the regions scanned. PMID:27403994

  11. Evaluación de marcadores moleculares asociados con resistencia a gota (Phytophthora infestans L. en papas diploides y tetraploides

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    D. K. Juyó

    2011-07-01

    Full Text Available Título en ingles: Evaluation of molecular markers associated with resistance to late blight (Phytophthora infestans L.  in diploid and tetraploid potatoes Resumen La papa, cultivo de importancia a nivel mundial es gravemente afectado por gota, enfermedad ocasionada por el oomycete Phytophthora infestans. Actualmente la forma más efectiva para combatir la enfermedad es mediante el desarrollo de cultivares resistentes al patógeno. Para esto, una estrategia es identificar genes que confieran resistencia al patógeno, para lo cual se buscan marcadores asociados con el carácter de resistencia. En este estudio se evaluaron marcadores moleculares tipo SCAR (Sequence Characterized Amplified Region: CosA, GP179, BA47f2 y Prp1 asociados con resistencia a P. infestans y el gen de resistencia R1, en 22 cultivares tetraploides pertenecientes a la subespecie andigena y cinco especies silvestres. Se evaluó el polimorfismo y se determinó si los alelos polimórficos permitían diferenciar genotipos resistentes de susceptibles. Se comparó el  tamaño de los fragmentos obtenidos con los fragmentos esperados asociados con resistencia de acuerdo a reportes. El análisis se realizó considerando presencia/ausencia de los fragmentos: CosA210, CosA250, R11400, R11800, BA47f2500, GP179570, Prp1300, Prp1600, y Prp1900. Los resultados indicaron que en los cultivares tetraploides y silvestres, se presentaron polimorfismos en todos los marcadores evaluados, con excepción del marcador GP179. No se encontró correlación entre el rasgo de resistencia y los alelos. Los resultados de este estudio muestran que hay repuesta diferencial a los marcadores entre las subsp. tuberosum y subsp. Andigena.   Palabras clave: Phytophthora infestans, resistencia a gota, marcadores diagnóstico, Solanum tuberosum subsp. Andigena. Abstract Potato is an important worldwide crop seriously affected by late blight disease caused by the oomycete Phytophthora infestans. Currently, the

  12. Progression of Stargardt Disease as Determined by Fundus Autofluorescence in the Retrospective Progression of Stargardt Disease Study (ProgStar Report No. 9).

    Science.gov (United States)

    Strauss, Rupert W; Muñoz, Beatriz; Ho, Alexander; Jha, Anamika; Michaelides, Michel; Cideciyan, Artur V; Audo, Isabelle; Birch, David G; Hariri, Amir H; Nittala, Muneeswar G; Sadda, SriniVas; West, Sheila; Scholl, Hendrik P N

    2017-11-01

    Sensitive outcome measures for disease progression are needed for treatment trials of Stargardt disease. To describe the yearly progression rate of atrophic lesions in the retrospective Progression of Stargardt Disease study. A multicenter retrospective cohort study was conducted at tertiary referral centers in the United States and Europe. A total of 251 patients aged 6 years or older at baseline, harboring disease-causing variants in ABCA4 (OMIM 601691), enrolled in the study from 9 centers between August 2, 2013, and December 12, 2014; of these patients, 215 had at least 2 gradable fundus autofluorescence images with atrophic lesion(s) present in at least 1 eye. Areas of definitely decreased autofluorescence (DDAF) and questionably decreased autofluorescence were quantified by a reading center. Progression rates were estimated from linear mixed models with time as the independent variable. Yearly rate of progression using the growth of atrophic lesions measured by fundus autofluorescence. A total of 251 participants (458 study eyes) were enrolled. Images from 386 eyes of 215 participants (126 females and 89 males; mean [SD] age, 29.9 [14.7] years; mean [SD] age of onset of symptoms, 21.9 [13.3] years) showed atrophic lesions present on at least 2 visits and were graded for 2 (156 eyes), 3 (174 eyes), or 4 (57 eyes) visits. A subset of 224 eyes (123 female participants and 101 male participants; mean [SD] age, 33.0 [15.1] years) had areas of DDAF present on at least 2 visits; these eyes were included in the estimation of the progression of the area of DDAF. At the first visit, DDAF was present in 224 eyes (58.0%), with a mean (SD) lesion size of 2.2 (2.7) mm2. The total mean (SD) area of decreased autofluorescence (DDAF and questionably decreased autofluorescence) at first visit was 2.6 (2.8) mm2. Mean progression of DDAF was 0.51 mm2/y (95% CI, 0.42-0.61 mm2/y), and of total decreased fundus autofluorescence was 0.35 mm2/y (95% CI, 0.28-0.43 mm2/y). Rates of

  13. Exploration of the Visual System: Part 2: In Vivo Analysis Methods: Virtual-Reality Optomotor System, Fundus Examination, and Fluorescent Angiography.

    Science.gov (United States)

    Marcelli, Fabienne; Escher, Pascal; Schorderet, Daniel F

    2012-09-01

    The mouse has emerged as an animal model for many diseases. At IRO, we have used this animal to understand the development of many eye diseases and treatment of some of them. Precise evaluation of vision is a prerequisite for both these approaches. In this unit we describe three ways to measure vision: testing the optokinetic response, and evaluating the fundus by direct observation and by fluorescent angiography. Curr. Protoc. Mouse Biol. 2:207-218 © 2012 by John Wiley & Sons, Inc. Copyright © 2012 John Wiley & Sons, Inc.

  14. Estado nutricional asociado a características sociodemográficas en el adulto mayor peruano

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    Carolina Tarqui-Mamani

    Full Text Available Objetivos. Describir el estado nutricional en adultos mayores y su asociación con características sociodemográficas. Materiales y métodos. Se realizó un estudio transversal analítico. El muestreo. fue probabilístico, estratificado y multietápico. El estado nutricional se evalúo mediante el índice de masa corporal (IMC según la clasificación del estado nutricional para el adulto mayor del Ministerio de Salud de Perú. El análisis estadístico consideró la ponderación necesaria para muestras complejas. Resultados. Se incluyó a 7267 adultos mayores con una media de edad de 70,1 ± 8,3 años. El 26,8% presentaron delgadez, 21,7% sobrepeso y 10,6% obesidad. El analfabetismo (OR 1,9; IC 95%: 1,2-3,0, nivel educativo primario (OR 1,9; IC 95%:1,3-2,9, pobreza extrema (OR 2,0; IC 95%:1,6-2,5, residir en área rural (OR 1,8; IC 95%:1,5-2,1, sierra (OR 1,6; IC 95%: 1,2-2,2 o selva (OR 1,6; IC 95%:1,1-2,2 fueron factores asociados a delgadez. El sexo femenino (OR 1,8; IC 95%:1,4-2,1, residir en área urbana (OR 2,0; IC 95%: 1,6-2,5 o costa (OR 1,5; IC 95%:1,2-1,8; y ser no pobre (OR 1,9; IC 95%: 1,3-2,9 se asoció a sobrepeso. El sexo femenino (OR 3,1; IC 95%: 2,3-4,1, nivel educativo primario (OR 2,4; IC 95%: 1,5-4,0 y secundario (OR 2,0; IC 95%: 1,2-3,4; vivir en área urbana (OR 2,2; IC 95%:1,6-2,9, la costa (OR 1,8; IC 95%: 1,3-2,4, Lima Metropolitana (OR 1,6; IC 95%:1,1-2,2 selva (OR 1,6; IC 95%: 1,1-2,2, y ser no pobre (OR 3,5; IC 95%:1,8-7,0 estuvieron asociados a obesidad. Conclusiones. Los datos sugieren que tanto la delgadez como el exceso de peso son frecuentes en la población de adultos mayores estudiada.

  15. FACTORES ASOCIADOS AL SOBREPESO Y LA OBESIDAD EN ESCOLARES DE 8 A 9 AÑOS DE BARCELONA

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    Francesca Sánchez-Martínez

    2016-01-01

    Full Text Available Fundamentos: El sobrepeso y la obesidad infantil han aumentado progresivamente en las últimas décadas, especialmente en países del sur de Europa. El objetivo del estudio fue identificar la prevalencia de sobrepeso, obesidad y sus determinantes en escolares de 8-9 años de Barcelona. Métodos: Estudio transversal descriptivo de una muestra representativa de 3.262 escolares en 2011. Se calculó el Índice de Masa Corporal (IMC siguiendo los criterios establecidos por la Organización Mundial de la Salud (z-scores. Se estudiaron variables sobre conducta alimentaria, actividad física y uso de nuevas tecnologías mediante 2 cuestionarios. Se ajustaron modelos de regresión logística, obteniendo odds ratio ajustadas e intervalos de confianza (95%. Resultados: La prevalencia de sobrepeso fue del 24,0% y de obesidad del 12,7%. La obesidad fue significativamente mayor en niños que en niñas (14,8% vs. 10,8%. No se observaron diferencias estadísticamente significativas según IMC en el cumplimiento de las recomendaciones de práctica de actividad física ni uso de nuevas tecnologías. Los factores asociados a la obesidad en niños fueron asistir a escuela situada en barrios de nivel socioeconómico desfavorable [ORa=1,88 (1,35-2,63], pertenecer a familia inmigrante [ORa=1,57 (1,12- 2,20], no comer en el colegio [ORa=1,76 (1,20-2,59] y hacer alguna comida solo [ORa=1,95 (1,27-3,00]. En niñas fueron pertenecer a familia monoparental [ORa=1,58 (1,06-2,34] y familia inmigrante [ORa=1,53 (1,07-2,18]. Conclusiones: La prevalencia de obesidad infantil en Barcelona es alta. Es más frecuente en niños, siendo los determinantes sociales los factores asociados de mayor relevancia.

  16. Factores asociados con la aparición de disfunciones sexuales en una población femenina

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    Wilfredo Guibert Reyes

    1998-02-01

    Full Text Available Se realiza un estudio explicativo para determinar la frecuencia de las disfunciones sexuales y algunos de los factores biológicos, psicosociales, culturales y ambientales asociados con la aparición de éstas en el período de 1 año, a partir de agosto de 1993 en Alamar. Se expresa que la muestra está compuesta por 48 mujeres mayores de 15 años, un grupo de estudio de 24, e igual cantidad de controles. Se les aplica una encuesta de 30 preguntas, cuyos resultados se muestran en 5 tablas y se utiliza el cálculo porcentual para estimar la frecuencia y odds ratio con intervalo de confianza al 95 %, para valorar fuerza de asociación entre las variables. Se encuentra que las difunciones sexuales femeninas de mayor frecuencia son el deseo sexual inhibido y la anorgasmia, que las variables ingestión de fármacos, ausencia de salud física, poco deseo sexual, comunicación deficiente de pareja y no recibir educación sexual, son factores de riesgo que están fuertemente asociados con la aparición de disfunciones sexuales en nuestras mujeres y tienen relación causal con ellas. Se señala que los factores ambientales no se asocian con la aparición de disfunciones sexualesAn explanatory study was conducted to determine the frequency of sexual dysfunctions and some of the biological, psychosocial, cultural and environmental factors associated with the appearance of these disorders from August, 1993, to August, 1994, in Alamar. The sample was composed of 48 women over 15, a case-base study consisting of 24 women, and the same number of controls. A survey with 30 questions was applied and the results were shown in 5 tables. Percentage was calculated to estimate the frequency and odds ratio with a confidence interval at 95 % so as to assess the force of association among the variables. It was found that the most frequent female sexual dysfunctions are the inhibited sexual desire and the anorgasmy, and that drug taking, the absence of physical health

  17. Factores sociales asociados con la utilización de los servicios de atención prenatal en Ecuador

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    Amaya Sánchez-Gómez

    Full Text Available RESUMEN Objetivos La atención prenatal es uno de los pilares de la salud pública y permite el acceso a intervenciones tales como la prevención de la transmisión materno-infantil del VIH y de la sífilis congénita. Este artículo tiene como objetivo describir los factores sociales asociados con la utilización de los servicios de atención prenatal en Ecuador. Métodos Entre 2011 y 2012, se realizó un análisis de la información procedente de las historias clínicas y de la entrevista a las participantes, que integraron una muestra probabilística a nivel nacional de 5 998 mujeres atendidas por parto o aborto en 15 servicios sanitarios en Ecuador con el objetivo de estimar la prevalencia de VIH, sífilis, enfermedad de Chagas y la cobertura de atención prenatal. Resultados El estudio mostró que 94,1% de las mujeres había acudido a algún control prenatal, pero la asistencia al menos a cuatro controles fue 73,1%. Se encontró que el menor nivel educativo, el mayor número de embarazos, la ocupación en el sector agrícola o ganadero y la pertenencia a los grupos étnicos indígena, afroecuatoriano u otros minoritarios fueron factores asociados con la falta de uso (ningún control prenatal o al uso inadecuado de la atención prenatal (menos de cuatro controles o primer control después de las 20 semanas de gestación en Ecuador. Conclusiones Estos resultados apuntan a la persistencia de desigualdades marcadas en el acceso y en la utilización de servicios de atención prenatal atribuibles a factores socioeconómicos y a la necesidad de fortalecer las estrategias para su abordaje para alcanzar la meta de la cobertura universal de atención prenatal.

  18. Factores asociados al ejercicio de la sexualidad de las y los adolescentes escolarizados de Cartagena – Colombia 2008

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    Carmen Elena Díaz Montes

    2014-03-01

    Full Text Available Title: Associated factors in the sexual practices of school adolescents of Cartagena- Colombia 2008Objetivo: Establecer las prácticas sexuales y los factores asociados al ejercicio de la sexualidad de las y los adolescentes escolarizados en Cartagena. Metodología: Estudio transversal, población 104.088 adolescentes estudiantes de secundaria en colegios oficiales y privados de Cartagena. Muestra 1.035 adolescentes, intervalo de confianza 95%, error 2%. Muestreo; multietapico. Se utilizaron una escala de conocimientos y actitudes y la escala Francis para valorar religiosidad. Resultados: La edad promedio de inicio de relaciones sexuales fue de 14.1 años, el 17% de los adolescentes ha tenido relaciones sexuales. Tener relaciones sexuales se asocia con ser varón, mayor grado de escolaridad, consumir cigarrillo, pertenecer a un grupo social, desigualdad de género, tener pareja y considerarla estable. Tener relaciones sexuales es más frecuente, en adolescentes de colegios públicos que privados. Conclusión: de los veintidós factores estudiados, ocho factores se mantuvieron fuertemente asociados al inicio de relaciones sexuales.AbstractObjective: To establish the sexual practices and the associated factors of the sexual behavior of school adolescents of Cartagena. Methodology: Transversal study, population 104.088 adolescent students of Secondary School of Public and private schools of Cartagena. Sample 1.035 adolescents, confidence level 95 %, and error 2 %. Sampling: multistage. Two scales of knowledge and attitudes were used, and the Francis scale. Results: The average age to start sexual relations was 14.1, 17% of the adolescents have had sexual relationships. To have sexual relations is associated significantly with the fact of being male, being in a higher grade, cigarette consumption, belonging to a social group, gender inequality, having a partner and considering him/her stable. Sexual relations are more common in public

  19. Adenopatía supraclavicular como forma de presentación de un carcinoma de cérvix asociado al complejo esclerosis tuberosa con linfangioleiomiomatosis

    OpenAIRE

    Pablo López Mato; Alfonso Varela Fariña; Elena Seco Hernández; Antonio J. Chamorro Fernández

    2013-01-01

    La linfangioleiomiomatosis es una proliferación del tejido muscular broncovascular que recientemente se ha definido como una expresión incompleta de la entidad “complejo esclerosis tuberosa”, una facomatosis a la que se asocian diversas neoplasias. Presentamos un caso de carcinoma de cérvix con metástasis supraclaviculares y cervicales, asociado a linfangioleiomiomatosis en el contexto de un “complejo esclerosis tuberosa”.

  20. Adenopatía supraclavicular como forma de presentación de un carcinoma de cérvix asociado al complejo esclerosis tuberosa con linfangioleiomiomatosis

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    Pablo López Mato

    2013-09-01

    Full Text Available La linfangioleiomiomatosis es una proliferación del tejido muscular broncovascular que recientemente se ha definido como una expresión incompleta de la entidad “complejo esclerosis tuberosa”, una facomatosis a la que se asocian diversas neoplasias. Presentamos un caso de carcinoma de cérvix con metástasis supraclaviculares y cervicales, asociado a linfangioleiomiomatosis en el contexto de un “complejo esclerosis tuberosa”.