971 resultados para visual diagnosis
Resumo:
Most indices for the assessment of wear of various aetiologies include the distinction between 'enamel still present' and 'dentine exposed' for grading. Since the visual diagnosis of exposed dentine has not yet been validated, the present study is a first attempt to investigate its accuracy and consistency. Sixty-one examiners (23 scientists, 18 university dentists and 20 dental students) were asked to diagnose 49 tooth areas with different grades of wear and to decide whether dentine was exposed (positive test) or not (negative test). Afterwards, the teeth were histologically evaluated. In 44 areas, dentine (also in all cases with minor wear) was exposed, and in 5 areas enamel was present. Overall sensitivity was 0.65, specificity 0.88 and the proportion of correct diagnoses was 0.67. The diagnosis 'dentine is exposed' was about 5 times as likely and the diagnosis 'dentine is not exposed' half as likely to come from an area with exposed dentine than from an enamel-covered area. The closeness of the visual diagnosis to the histological findings was only fair (kappa=0.27), no significant impact of professional experience was found. For inter- and intra-examiner agreement, kappa was 0.28 and 0.55, respectively. It was concluded that the diagnosis of exposed dentine is difficult.
Resumo:
Foi notado, em área de cultivo experimental em Botucatu (SP), que a soja, na época de enchimento das vagens, apresentava folhas com cor amarelada, que evoluía para palha, com tons arroxeados no limbo foliar e nos pecíolos. Esses sintomas eram compatíveis com as descrições mais genéricas de deficiência de P para outras espécies, apesar de não estarem descritos para soja. Foi conduzido um experimento em vasos com areia lavada e solução nutritiva, com o objetivo de reproduzir os sintomas observados em condição de campo. Foram cultivadas três plantas de soja por vaso, em ambiente aberto. Os sintomas de deficiência de P apareceram inicialmente nas folhas mais velhas, que ficaram amareladas, conservando algumas nervuras verdes. O tom amarelado foi-se intensificando, adquirindo tons avermelhados e, posteriormente, arroxeados. Notou-se ainda colapso do pecíolo das folhas com sintomas de deficiência. A fase de pegamento de vagens de soja mostrou-se mais sensível à deficiência de P do que a fase de enchimento de grãos podendo ocorrer recuperação de parte da produtividade pela produção de menor número de grãos e vagens chochas e aumento no tamanho de grão, se a deficiência ocorrer tardiamente e não for muito severa.
Resumo:
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Resumo:
The objective was to evaluate the effect of the omission of macronutrient and micronutrient boron in dry matter production, the characterization of the symptoms of nutritional deficiencies and mineral composition in plants of ipeca, an experiment was conducted in greenhouse conditions by the technique the missing element and visual diagnosis. A randomized block experimental design with four repetitions and the treatments were: complete and omissions of N, P, K, Ca, Mg, S and B. The analytical results demonstrated that the production of dry matter was affected in all of the treatments with omission of nutrients and that the ipeca plants presented characteristic symptoms of nutritional deficiencies due to the omissions of N, P, K, Ca, Mg, S and B and the concentrations of the macronutrients and of the micronutrient boron in the different parts of the ipeca plant varied when a certain nutrient was omitted in the solution.
Resumo:
We present assembly and application of an optical reflectometer for the analysis of dental erosion. The erosive procedure involved acid-induced softening and initial substance loss phases, which are considered to be difficult for visual diagnosis in a clinic. Change of the specular reflection signal showed the highest sensitivity for the detection of the early softening phase of erosion among tested methods. The exponential decrease of the specular reflection intensity with erosive duration was compared to the increase of enamel roughness. Surface roughness was measured by optical analysis, and the observed tendency was correlated with scanning electron microscopy images of eroded enamel. A high correlation between specular reflection intensity and measurement of enamel softening (r(2) ? -0.86) as well as calcium release (r(2) ? -0.86) was found during erosion progression. Measurement of diffuse reflection revealed higher tooth-to-tooth deviation in contrast to the analysis of specular reflection intensity and lower correlation with other applied methods (r(2) = 0.42-0.48). The proposed optical method allows simple and fast surface analysis and could be used for further optimization and construction of the first noncontact and cost-effective diagnostic tool for early erosion assessment in vivo.
Resumo:
INTRODUCTION: Visual analysis is widely used to interpret regional cerebral blood flow (rCBF) SPECT images in clinical practice despite its limitations. Automated methods are employed to investigate between-group rCBF differences in research Studies but have rarely been explored in individual analyses.OBJECTIVES: To compare visual inspection by nuclear physicians with the automated statistical parametric mapping program using a SPECT dataset of patients with neurological disorders and normal control images.METHODS: Using statistical parametric mapping, 14 SPECT images from patients with various neurological disorders were compared individually with a databank of 32 normal images using a statistical threshold of p<0.05 (corrected for multiple comparisons at the level of individual voxels or clusters). Statistical parametric mapping results were compared with Visual analyses by a nuclear physician highly experienced in neurology (A) as well as a nuclear physician with a general background of experience (B) who independently classified images as normal or altered, and determined the location of changes and the severity.RESULTS: of the 32 images of the normal databank, 4 generated maps showing rCBF abnormalities (p<0.05, corrected). Among the 14 images from patients with neurological disorders, 13 showed rCBF alterations. Statistical parametric mapping and physician A completely agreed on 84.37% and 64.28% of cases from the normal databank and neurological disorders, respectively. The agreement between statistical parametric mapping and ratings of physician B were lower (71.18% and 35.71%, respectively).CONCLUSION: Statistical parametric mapping replicated the findings described by the more experienced nuclear physician. This finding suggests that automated methods for individually analyzing rCBF SPECT images may be a valuable resource to complement visual inspection in clinical practice.
Resumo:
National Highway Traffic Safety Administration, Washington, D.C.
Resumo:
Visual field assessment is a core component of glaucoma diagnosis and monitoring, and the Standard Automated Perimetry (SAP) test is considered up until this moment, the gold standard of visual field assessment. Although SAP is a subjective assessment and has many pitfalls, it is being constantly used in the diagnosis of visual field loss in glaucoma. Multifocal visual evoked potential (mfVEP) is a newly introduced method used for visual field assessment objectively. Several analysis protocols have been tested to identify early visual field losses in glaucoma patients using the mfVEP technique, some were successful in detection of field defects, which were comparable to the standard SAP visual field assessment, and others were not very informative and needed more adjustment and research work. In this study, we implemented a novel analysis approach and evaluated its validity and whether it could be used effectively for early detection of visual field defects in glaucoma. OBJECTIVES: The purpose of this study is to examine the effectiveness of a new analysis method in the Multi-Focal Visual Evoked Potential (mfVEP) when it is used for the objective assessment of the visual field in glaucoma patients, compared to the gold standard technique. METHODS: 3 groups were tested in this study; normal controls (38 eyes), glaucoma patients (36 eyes) and glaucoma suspect patients (38 eyes). All subjects had a two standard Humphrey visual field HFA test 24-2 and a single mfVEP test undertaken in one session. Analysis of the mfVEP results was done using the new analysis protocol; the Hemifield Sector Analysis HSA protocol. Analysis of the HFA was done using the standard grading system. RESULTS: Analysis of mfVEP results showed that there was a statistically significant difference between the 3 groups in the mean signal to noise ratio SNR (ANOVA p<0.001 with a 95% CI). The difference between superior and inferior hemispheres in all subjects were all statistically significant in the glaucoma patient group 11/11 sectors (t-test p<0.001), partially significant 5/11 (t-test p<0.01) and no statistical difference between most sectors in normal group (only 1/11 was significant) (t-test p<0.9). sensitivity and specificity of the HAS protocol in detecting glaucoma was 97% and 86% respectively, while for glaucoma suspect were 89% and 79%. DISCUSSION: The results showed that the new analysis protocol was able to confirm already existing field defects detected by standard HFA, was able to differentiate between the 3 study groups with a clear distinction between normal and patients with suspected glaucoma; however the distinction between normal and glaucoma patients was especially clear and significant. CONCLUSION: The new HSA protocol used in the mfVEP testing can be used to detect glaucomatous visual field defects in both glaucoma and glaucoma suspect patient. Using this protocol can provide information about focal visual field differences across the horizontal midline, which can be utilized to differentiate between glaucoma and normal subjects. Sensitivity and specificity of the mfVEP test showed very promising results and correlated with other anatomical changes in glaucoma field loss.
Resumo:
CONCLUSIONS: The new HSA protocol used in the mfVEP testing can be applied to detect glaucomatous visual field defects in both glaucoma and glaucoma suspect patients. Using this protocol can provide information about focal visual field differences across the horizontal midline, which can be utilized to differentiate between glaucoma and normal subjects. Sensitivity and specificity of the mfVEP test showed very promising results and correlated with other anatomical changes in glaucoma field loss. PURPOSE: Multifocal visual evoked potential (mfVEP) is a newly introduced method used for objective visual field assessment. Several analysis protocols have been tested to identify early visual field losses in glaucoma patients using the mfVEP technique, some were successful in detection of field defects, which were comparable to the standard automated perimetry (SAP) visual field assessment, and others were not very informative and needed more adjustment and research work. In this study we implemented a novel analysis approach and evaluated its validity and whether it could be used effectively for early detection of visual field defects in glaucoma. METHODS: Three groups were tested in this study; normal controls (38 eyes), glaucoma patients (36 eyes) and glaucoma suspect patients (38 eyes). All subjects had a two standard Humphrey field analyzer (HFA) test 24-2 and a single mfVEP test undertaken in one session. Analysis of the mfVEP results was done using the new analysis protocol; the hemifield sector analysis (HSA) protocol. Analysis of the HFA was done using the standard grading system. RESULTS: Analysis of mfVEP results showed that there was a statistically significant difference between the three groups in the mean signal to noise ratio (ANOVA test, p < 0.001 with a 95% confidence interval). The difference between superior and inferior hemispheres in all subjects were statistically significant in the glaucoma patient group in all 11 sectors (t-test, p < 0.001), partially significant in 5 / 11 (t-test, p < 0.01), and no statistical difference in most sectors of the normal group (1 / 11 sectors was significant, t-test, p < 0.9). Sensitivity and specificity of the HSA protocol in detecting glaucoma was 97% and 86%, respectively, and for glaucoma suspect patients the values were 89% and 79%, respectively.
Resumo:
Diabetes is an increasingly prevalent disease worldwide. Providing early management of the complications can prevent morbidity and mortality in this population. Peripheral neuropathy, a significant complication of diabetes, is the major cause of foot ulceration and amputation in diabetes. Delay in attending to complication of the disease contributes to significant medical expenses for diabetic patients and the community. Early structural changes to the neural components of the retina have been demonstrated to occur prior to the clinically visible retinal vasculature complication of diabetic retinopathy. Additionally visual functionloss has been shown to exist before the ophthalmoscopic manifestations of vasculature damage. The purpose of this thesis was to evaluate the relationship between diabetic peripheral neuropathy and both retinal structure and visual function. The key question was whether diabetic peripheral neuropathy is the potential underlying factor responsible for retinal anatomical change and visual functional loss in people with diabetes. This study was conducted on a cohort with type 2 diabetes. Retinal nerve fibre layer thickness was assessed by means of Optical Coherence Tomography (OCT). Visual function was assessed using two different methods; Standard Automated Perimetry (SAP) and flicker perimetry were performed within the central 30 degrees of fixation. The level of diabetic peripheral neuropathy (DPN) was assessed using two techniques - Quantitative Sensory Testing and Neuropathy Disability Score (NDS). These techniques are known to be capable of detecting DPN at very early stages. NDS has also been shown as a gold standard for detecting 'risk of foot ulceration'. Findings reported in this thesis showed that RNFL thickness, particularly in the inferior quadrant, has a significant association with severity of DPN when the condition has been assessed using NDS. More specifically it was observed that inferior RNFL thickness has the ability to differentiate individuals who are at higher risk of foot ulceration from those who are at lower risk, indicating that RNFL thickness can predict late-staged DPN. Investigating the association between RNFL and QST did not show any meaningful interaction, which indicates that RNFL thickness for this cohort was not as predictive of neuropathy status as NDS. In both of these studies, control participants did not have different results from the type 2 cohort who did not DPN suggesting that RNFL thickness is not a marker for diagnosing DPN at early stages. The latter finding also indicated that diabetes per se, is unlikely to affect the RNFL thickness. Visual function as measured by SAP and flicker perimetry was found to be associated with severity of peripheral neuropathy as measured by NDS. These findings were also capable of differentiating individuals at higher risk of foot ulceration; however, visual function also proved not to be a maker for early diagnosis of DPN. It was found that neither SAP, nor flicker sensitivity have meaningful associations with DPN when neuropathy status was measured using QST. Importantly diabetic retinopathy did not explain any of the findings in these experiments. The work described here is valuable as no other research to date has investigated the association between diabetic peripheral neuropathy and either retinal structure or visual function.
Resumo:
The prevalence and the causes of childhood visual impairment in Finland during the 1970s and the 1980s were investigated, with special attention to risk factors and further prevention of visual impairment in children. The primary data on children with visual impairment were obtained from the Finnish Register of Visual Impairment, one of the patient registers kept up by the National Research and Development Centre for Welfare and Health (Stakes). The data were supplemented from other registers in Stakes and from patient records of the children in Finnish central hospitals. Visual impairment had been registered in 556 children from a population of 1,138,326 children between ages 0-17, born from 1972 through 1989. The age-specific prevalence of registered visual impairment was 49/100,000 in total. Of them, 23/100,000 were blind children and 11/100,000 were children born prematurely. Boys were impaired more often and more severely than girls. Congenital malformations (52%), systemic diseases (48%), and multiple impairments (50%) were common. The main ophthalmic groups of visual impairment were retinal diseases (35%), ocular malformations (29%), and neuro-ophthalmological disorders (29%). Optic nerve atrophy was the most common diagnosis of visual impairment (22%), followed by congenital cataract (11%), retinopathy of prematurity (10%), and cerebral visual impairment (8%). Genetic factors (42%) were the most common etiologies of visual impairment, followed by prenatal (30%) and perinatal (21%) factors. The highest rates of blindness were seen in cerebral visual impairment (83%) and retinopathy of prematurity (82%). Retinopathy of prematurity had developed in the children born at a gestational age of 32 weeks or earlier. Significant risks for visual impairment were found in the association with preterm births, prenatal infections, birth asphyxia, neonatal respiratory difficulties, mechanical ventilation lasting over two weeks, and hyperbilirubinemia. A rise in blind and multi-impaired children was seen during the study period, associating with increases in the survival of preterm infants with extremely low birth weight. The incidence of visual impairment in children born prematurely was seven times higher than in children born at full term. A reliable profile of childhood visual impairment was obtained. The importance of highly qualified antenatal, neonatal, and ophthalmological care was clearly proved. The risks associated with pre- and perinatal disorders during pregnancy must be emphasized, e.g. the risks associated with maternal infections and the use of tobacco, alcohol, and drugs during pregnancy. Obvious needs for gene therapies and other new treatments for hereditary diseases were also proved.
Resumo:
O objetivo do presente trabalho foi avaliar in vivo a detecção de cárie através do exame visual ICDAS, transiluminação por fibra ótica combinado ao ICDAS e exame radiográfico. Um total de 2.279 superfícies proximais e cicatrículas e fissuras em incisivos superiores, pré-molares e molares permanentes e 272 superfícies em molares decíduos em72 escolares (8 a 18 anos) foram avaliadas por um examinador treinado. Os sete escores para detecção de cárie primária do sistema visual ICDAS foram aplicados. Dois equipamentos de transiluminação por fibra ótica foram avaliados: FOTI Schott (SCH), com ponta de fibra ótica com 0,5mm de diâmetro, e FOTI Microlux (MIC), com diâmetro da ponta 3 mm. Durante o exame combinado FOTI/ICDAS, a fibra ótica era utilizada tanto para iluminar quanto para transiluminar a superfície sob avaliação. O exame radiográfico (RX) consistiu de radiografias interproximais posteriores e periapicais anteriores. Os exames foram realizados em consultório odontológico após escovação supervisionada. No primeiro dia de exame, o exame visual utilizando o ICDAS era realizado e em seguida, o exame combinado ao MIC ou SCH. Logo após era realizado o exame radiográfico. Após uma semana, novamente o ICDAS era realizado, e em seguida o exame combinado com o equipamento de FOTI não utilizado na semana anterior. Os exames foram repetidos em 10 pacientes após intervalo mínimo de uma semana para avaliação da reprodutibilidade intra-examinador, a qual apresentou valores de 0,95 (ICDAS), 0,94 (MIC), 0,95 (SCH) e 0,99 (RX) pelo kappa ponderado. Em cicatrículas e fissuras de permanentes, o RX julgou que um número maior de superfícies apresentava lesão em dentina (53) do que os outros métodos (34 a 36); porém não detectou nenhuma lesão em esmalte, as quais foram identificadas pelo ICDAS (94), SCH (107) e MIC (91). Em proximais permanentes, a transiluminação por fibra ótica identificou maior número de proximais como lesão em esmalte - 150 (SCH) e 139 (MIC) - do que o exame visual (106), enquanto o RX identificou somente 43. Em oclusais de decíduos, os quatro métodos julgaram um número aproximadamente similar de superfícies sem lesão (52 a 59) ou com lesão em dentina (21 a 26), assim como para lesões proximais em dentina (31 a 36). Entretanto um número reduzido de lesões proximais decíduas em esmalte foi julgado pelo exame radiográfico (3) em comparação com os outros métodos (15 a 16). Em decíduos, o ICDAS e o FOTI combinado ao exame visual julgaram maior número de lesões proximais em esmalte que o exame radiográfico, sendo que número similar de lesões em dentina foram classificadas pelos quatro métodos em oclusais e proximais de molares decíduos. Em cicatrículas e fissuras de permanentes, tanto o exame visual ICDAS quanto sua combinação aos dois equipamentos de transiluminação apresentaram maior similaridade de superfícies julgadas como lesão em esmalte ou como lesão em dentina, enquanto o exame radiográfico classificou mais superfícies como lesão em dentina e nenhuma como lesão em esmalte. A adição da transiluminação por fibra ótica ao exame visual aumentou em um terço a detecção das lesões cariosas proximais julgadas em dentina pelo ICDAS isoladamente e aproximadamente quadruplicou o número daquelas assim classificadas pela avaliação radiográfica em permanentes.
Resumo:
The sense of vision is people’s main source of information acquisition, hence the importance of a right diagnosis and correction, if necessary, of any faults for proper learning, especially in the early years of schooling. This article discusses the results of a survey of teachers in Andalusian schools that aimed at highlighting their knowledge of their students’ possible visual deficiencies, and its possible impact on school performance. The results indicate that such knowledge is generally limited to the type of refractive anomalies, and that they think that such anomalies are well treated in their students. Despite the importance they attach to these deficiencies on school learning, they think that other factors may have a greater role. They also consider that better training on this topic is necessary.