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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Predicting visual acuity from visual field sensitivity in age-related macular degeneration

Denniss, Jonathan, Baggaley, H.C., Astle, A.T. January 2018 (has links)
Yes / Purpose: To investigate how well visual field sensitivity predicts visual acuity at the same locations in macular disease, and to assess whether such predictions may be useful for selecting an optimum area for fixation training. Methods: Visual field sensitivity and acuity were measured at nine locations in the central 10° in 20 people with AMD and stable foveal fixation. A linear mixed model was constructed to predict acuity from sensitivity, taking into account within-subject effects and eccentricity. Cross validation was used to test the ability to predict acuity from sensitivity in a new patient. Simulations tested whether sensitivity can predict nonfoveal regions with greatest acuity in individual patients. Results: Visual field sensitivity (P < 0.0001), eccentricity (P = 0.007), and random effects of subject on eccentricity (P = 0.043) improved the model. For known subjects, 95% of acuity prediction errors (predicted − measured acuity) fell within −0.21 logMAR to +0.18 logMAR (median +0.00 logMAR). For unknown subjects, cross validation gave 95% of acuity prediction errors within −0.35 logMAR to +0.31 logMAR (median −0.01 logMAR). In simulations, the nonfoveal location with greatest predicted acuity had greatest “true” acuity on median 26% of occasions, and median difference in acuity between the location with greatest predicted acuity and the best possible location was +0.14 logMAR (range +0.04 to +0.17). Conclusions: The relationship between sensitivity and acuity in macular disease is not strongly predictive. The location with greatest sensitivity on microperimetry is unlikely to represent the location with the best visual acuity, even if eccentricity is taken into account. / College of Optometrists Postdoctoral Research Award (JD and ATA; London, UK) and National Institute for Health Research (NIHR) Postdoctoral Fellowship (ATA; London, UK). Presents independent research funded by the NIHR. / Research Development Fund Publication Prize Award winner, August 2018.
32

"Comparação entre a sensibilidade do hemicampo visual temporal e do hemicampo visual nasal em pacientes com estrabismo convergente de aparecimento precoce" / Comparative study between the visual temporal hemifield and the visual nasal hemifield sensitivity in patients with early onset convergent strabismus

Polati, Mariza Aparecida 12 April 2005 (has links)
Com o objetivo de avaliar a hipótese de redução da sensibilidade do hemicampo nasal do campo visual, o que aumentaria a assimetria temporal-nasal dos hemicampos, nos pacientes com estrabismo convergente de aparecimento precoce (antes de dois anos de idade) em comparação aos normais, foram estudados os dois olhos de 66 pacientes, 33 estrábicos e 33 normais, com idade que variou de 7 a 30 anos, com o método da perimetria estática, utilizando-se o programa SITA Standard, do perímetro Humphrey HFA-II Série 700. / With the objective of analysing the hypothesis that a reduction in sensitivity of the nasal hemifield, that in turn would lead to an increase in the nasotemporal asymmetry of the visual field, in patients with early onset convergent strabismus - before 2 years of age - if compared to normal patients, both eyes of 66 patients - 33 esotropes and 33 normal - were studied. Patient's age varied from 7 - 30 years. The method of examination was that of Static Perimetry utilizing the Sita Standard program, of the Humphrey perimeter HFA II 700 Series. The results depicted a clear accentuation of the nasotemporal asymmetry in esotropes if compared to normal patients. This asymmetry was due to the evident decrease of sensitivity in the most peripheral of the chosen points of study. The quantitative sum of values of sensitivity of these points exhibited an average reduction of -15,71% in relation to the normal patients. For both groups, normal and esotropes, there was no difference in values of sensitivity between the to eyes.
33

"Comparação entre a sensibilidade do hemicampo visual temporal e do hemicampo visual nasal em pacientes com estrabismo convergente de aparecimento precoce" / Comparative study between the visual temporal hemifield and the visual nasal hemifield sensitivity in patients with early onset convergent strabismus

Mariza Aparecida Polati 12 April 2005 (has links)
Com o objetivo de avaliar a hipótese de redução da sensibilidade do hemicampo nasal do campo visual, o que aumentaria a assimetria temporal-nasal dos hemicampos, nos pacientes com estrabismo convergente de aparecimento precoce (antes de dois anos de idade) em comparação aos normais, foram estudados os dois olhos de 66 pacientes, 33 estrábicos e 33 normais, com idade que variou de 7 a 30 anos, com o método da perimetria estática, utilizando-se o programa SITA Standard, do perímetro Humphrey HFA-II Série 700. / With the objective of analysing the hypothesis that a reduction in sensitivity of the nasal hemifield, that in turn would lead to an increase in the nasotemporal asymmetry of the visual field, in patients with early onset convergent strabismus - before 2 years of age - if compared to normal patients, both eyes of 66 patients - 33 esotropes and 33 normal - were studied. Patient's age varied from 7 - 30 years. The method of examination was that of Static Perimetry utilizing the Sita Standard program, of the Humphrey perimeter HFA II 700 Series. The results depicted a clear accentuation of the nasotemporal asymmetry in esotropes if compared to normal patients. This asymmetry was due to the evident decrease of sensitivity in the most peripheral of the chosen points of study. The quantitative sum of values of sensitivity of these points exhibited an average reduction of -15,71% in relation to the normal patients. For both groups, normal and esotropes, there was no difference in values of sensitivity between the to eyes.
34

Utilisation of the structure of the retinal nerve fiber layer and test strategy in visual field examination

Nevalainen, J. (Jukka) 08 June 2010 (has links)
Abstract The aim of this study was to create a mathematical model of the retinal nerve fiber layer and of the entire hill of vision, and to compare different perimetric methods and test grids in the detection of visual field loss in glaucoma and optic neuritis. A mathematical model of the retinal nerve fiber layer was developed, based on traced nerve fiber bundle trajectories extracted from 55 fundus photographs of 55 human subjects. The model resembled the typical retinal nerve fiber layer course within 20° eccentricity from the foveola. The standard deviation of the calculated corresponding angular location at the optic nerve head circumference ranged from less than 1° up to 18° (mean 8.8°). A smooth mathematical model of the hill of vision was created, based on 81 ophthalmologically healthy subjects. The model fit R2 was 0.72. Applying individually condensed test grids in 41 glaucomatous eyes of 41 patients enhanced remarkably the detection of progression. Seven out of 11 (64%) of the progressive scotomata detected by spatially condensed grids would have been missed by the conventional 6° × 6° grid. In 20 eyes of 20 patients with advanced glaucoma, the comparability of visual field areas obtained with semi-automated kinetic perimetry and automated static perimetry was satisfactory and within the range of the test-retest reliability of automated static perimetry. Using a standardized grid of 191 static targets within the central 30° visual field, the most common finding in 100 eyes of 99 patients with acute optic neuritis were central scotomas, accounting for 41% of all visual field defects in affected eyes. In conclusion, a model of the retinal nerve fiber layer was developed, which provided a detailed location specific estimate of the magnitude of the variability on the courses of retinal nerve fiber bundle trajectories in the human retina. A smooth mathematical model of the hill of vision with a satisfactory model fit was described for the 80° visual field. Individually condensed grids enabled the detection of a glaucomatous visual field progression more frequently and also earlier than conventional grids. Semi-automated kinetic perimetry was found to be a valuable alternative to automated static perimetry in monitoring advanced glaucomatous visual field loss. Using a grid with a higher spatial resolution may enhance the detection of small central visual field loss in optic neuritis.
35

Diagnostic imaging and the structure-function relationship in glaucoma

Denniss, Jonathan January 2010 (has links)
This thesis describes a series of investigations into the use of optic nerve head (ONH) imaging in primary open-angle glaucoma (POAG), and its relation to visual function. Accurate diagnosis is a key issue in POAG, particularly the difficult task of separating those with early disease from those healthy individuals who display signs of POAG. The purpose of this work is to improve diagnostic methods in glaucoma through use of ONH imaging and its relationship with visual field (VF) loss. First, the performance of a group of expert clinicians evaluating ONH photographs for glaucomatous damage was investigated. The results showed that even when their assessments are combined discrimination between eyes with and without POAG (based on VF loss) is far from perfect, highlighting the need for improvements in diagnosis. The possibility of combining structural and functional data to aid diagnosis was then considered. This requires VF loss and ONH damage to be strongly topographically related. The strength of this relationship was evaluated in 185 patients with POAG. 10,000 computer-generated maps between the ONH and VF were tested and the topographic relationship measured with each of these was compared to that using a published structure-based map. The weak topographic relationships found suggest that the application of these maps to individual patients is limited with current measures. The next chapter describes how a multispectral imaging (MSI, also called hyperspectral imaging) system was set-up for spatial evaluation of ONH oxygenation using a Beer-Lambert law model. Test-retest repeatability was tested and found to be acceptable for the purposes of the following studies. The MSI system was then used for an investigation of the relationship between ONH oxygenation and VF loss. 33 eyes of 18 patients underwent VF testing, MSI and HRT3 imaging. Superior-inferior asymmetries in VF sensitivity were compared to superior-inferior asymmetries in ONH oxygenation measured by MSI and in neuroretinal rim (NRR) area measured by HRT3. This way we take advantage of the typical progression of POAG and each eye acts as its own reference, negating the effect of a wide normal range and overlap between health and disease. This study found, for the first time, a strong association between ONH oxygenation and VF sensitivity. A re-analysis of the 33 ONH oxygenation maps was then performed to assess oxygenation only in the area of the NRR as defined by the HRT. Superior-inferior asymmetries in NRR oxygenation were then compared to superior-inferior asymmetries in VF loss, and the associations found were similarly strong. This study shows that MSI is capable of detecting areas of NRR deemed healthy tissue by structural imaging techniques, which are in fact poorly oxygenated and associated with VF defects. These findings show that NRR oxygenation measured by MSI is strongly related to VF loss. This important information complements existing technologies and may aid in the future diagnosis and management of patients with POAG.
36

Functional Monitoring after Trabeculectomy or XEN Microstent Implantation Using Spectral Domain Optical Coherence Tomography and Visual Field Indices—A Retrospective Comparative Cohort Study

Schargus, Marc, Busch, Catharina, Rehak, Matus, Meng, Jie, Schmidt, Manuela, Bormann, Caroline, Unterlauft, Jan Darius 27 April 2023 (has links)
The aim of this study was to compare the efficacy of trabeculectomy (TE), single XEN microstent implantation (solo XEN) or combined XEN implantation and cataract surgery (combined XEN) in primary open-angle glaucoma cases, naïve to prior surgical treatment, using a monocentric retrospective comparative cohort study. Intraocular pressure (IOP) and the number of IOP-lowering drugs (Meds) were monitored during the first 24 months after surgery. Further disease progression was monitored using peripapillary retinal nerve fiber layer (RNFL) thickness examinations using spectral domain optical coherence tomography (OCT) as well as visual acuity (VA) and visual field (VF) tests. In the TE group (52 eyes), the mean IOP decreased from 24.9 ± 5.9 to 13.9 ± 4.2 mmHg (p < 0.001) and Meds decreased from 3.2 ± 1.2 to 0.5 ± 1.1 (p < 0.001). In the solo XEN (38 eyes) and the combined XEN groups, the mean IOP decreased from 24.1 ± 4.7 to 15.7 ± 3.0 mmHg (p < 0.001) and 25.4 ± 5.6 to 14.7 ± 3.2 mmHg (p < 0.001), while Meds decreased from 3.3 ± 0.8 to 0.8 ± 1.2 (p < 0.001) and 2.7 ± 1.2 to 0.4 ± 1.0 (p < 0.001), respectively. The VF and VA indices showed no sign of further deterioration, the RNFL thickness further decreased in all treatment groups after surgery. TE and XEN led to comparable reductions in IOP and Meds. Although the VA and VF indices remained unaltered, the RNFL thickness continuously decreased in all treatment groups during the 24-month follow-up.
37

Manifestações oftalmológicas e neurológicas em portadores pré-sintomáticos e sintomáticos de ataxia espinocerebelar tipo 7

Azevedo, Pietro Baptista de January 2017 (has links)
Introdução: a ataxia espinocerebelar tipo 7 (SCA7) é um distúrbio neurodegenerativo autossômico dominante causado por uma repetição CAG expandida (CAGexp) no gene ATXN7, resultando na inserção de uma poliglutamina (poliQ) alongada na proteína ataxina-7. Em consequência, pacientes com SCA7 desenvolvem ataxia, espasticidade e outros sintomas neurológicos. A SCA 7 se destaca de outras SCAs por se associar à distrofia retiniana, causando deficiências visuais que podem levar à cegueira. Sendo uma das mais raras SCAs, pequenas séries de casos têm aparecido na literatura. Poucas delas buscaram correlacionar os achados neurológicos com os oftalmológicos; e a fase pré-clínica jamais foi sistematicamente investigada. Objetivo: descrever os achados neurológicos e oftalmológicos de uma coorte de casos de SCA 7, comparando as manifestações encontradas em sujeitos sintomáticos com as encontradas em portadores assintomáticos e em parentes não portadores, em uma abordagem exploratória que buscou levantar potenciais biomarcadores de progressão da doença. Métodos: trata-se de um estudo transversal onde pacientes com diagnóstico molecular de SCA7 realizado na nossa instituição foram identificados em nossos arquivos protegidos. Tanto eles como seus parentes foram convidados a participar da presente investigação. Sujeitos em risco de 50% foram incluídos se tivessem mais de 18 anos. Após o consentimento, dados clínicos e demográficos foram coletados entre junho de 2016 e setembro de 2017. A seguir, todos os participantes realizaram uma bateria de escalas clínicas voltadas à medida da ataxia (SARA, CCFS, PATA e 8 MW) e das manifestações neurológicas (NESSCA e INAS); um questionário de qualidade de vida relacionada à visão (NEI-VFQ 25); avaliação da acuidade visual melhor corrigida (AVMC), desvio médio em campimetria computadorizada (MD) e espessuras da mácula e da camada de células ganglionares na tomografia de coerência óptica (OCT). A escala SARA e a AVMC foram escolhidas como as variáveis de referência para a gravidade dos quadros. A análise molecular do ATXN7 foi feita, mas participantes do estudo e avaliadores foram mantidos cegos para seus resultados; os indivíduos em risco interessados em receber seus resultados foram enviados para o programa de testes pré-sintomáticos. Como não houve critérios a priori para estimar tamanhos de efeito e como a SCA7 é uma condição rara, não houve como decidir um tamanho de amostra. O estudo foi exploratório e por isso não foram feitas correções para múltiplas testagens. Um p de 0,05 foi eleito para definir significância, e testes estatísticos foram aplicados de acordo com as características das variáveis em estudo. Resultados: 12 portadores sintomáticos (grupo 2) e 8 indivíduos em risco (3 portadores - grupo 1 - e 5 não-portadores - grupo 0) foram incluídos neste estudo. Todas as variáveis contínuas à exceção da CAGexp tiveram distribuição 4 normal. A AVMC estava reduzida em todos os participantes sintomáticos e claramente diferente entre estes e os outros dois grupos (p <0,0001, ANOVA), enquanto os portadores assintomáticos e os não portadores tiveram resultados semelhantes. A AVMC média foi 20/143, 20/18 e 20/20 nos grupos 2, 1 e 0, respectivamente. Não surpreendentemente, o NEI-VFQ 25 também demonstrou uma diferença estatisticamente significativa, mas o que foi inesperado foi a forma progressivamente diferente entre os 3 grupos (grupo 0 = 92,76 ± 6,7; grupo 1 = 74,9 ± 55,5; grupo 2 = 58,0 ± 21,3) (p= 0,012, ANOVA com Tukey) O MD mostrou um padrão linear estatisticamente significativo para piorar do grupo controle (-1,34 ± 1,15dB) para o assintomático (-2,81 ± 1,66dB) e do grupo assintomático para sintomático (-10,54 ± 6,95dB) (p = 0,027, ANOVA com Tukey). Além disso, o MD correlacionou-se com a AVMC (p = 0,020; r = 0,660) e apresentou tendência de correlação com a SARA (p= 0,073; r= -0,535). As medidas de espessura macular distinguem completamente os 3 grupos (grupo 0 = 243,6 ± 22,2 μ; grupo 1 = 204,5 ± 14,1 μ; grupo 2 = 137,95 ± 34,6 μ) (p = 0,0001, ANOVA) e também se correlacionou significativamente com os dois critérios planejados de gravidade, SARA (p = 0,050; r = -0,577) e AVMC (p = 0,007; r = 0,730). Discussão: alterações oftalmológicas estavam presentes já nas fases pré-clínicas da doença, quando os escores obtidos das escalas neurológicas ainda não distinguem portadores assintomáticos de não portadores: a espessura macular medida por OCT e o MD medido pela campimetria computadorizada. Esses achados demonstram que o processo neurodegenerativo já se encontra em curso e é detectável por essas medidas anatômicas e funcionais da retina. Além disso, ambas as alterações detectadas em fases pré-clínicas, ao serem estudadas no grupo total de portadores sintomáticos e assintomáticos, se correlacionaram com os nossos padrões-ouro da gravidade da doença, SARA e AVMC. Os dois achados - início em fase pré-clínica e correlação com a progressão da doença medida por escores independentes - sugerem que a espessura macular medida por OCT e o MD medido pela campimetria computadorizada são potenciais candidatos a biomarcadores de estado (de progressão da doença) desde fases pré-manifestas na SCA7. / Background: spinocerebellar ataxia type 7 (SCA7) is an autosomal dominant neurodegenerative disorder caused by an expanded CAG repeat (CAGexp) at ATXN7 gene, resulting in the insertion of an elongated polyglutamine (polyQ) into the ataxin-7 protein. As a consequence, patients with SCA7 develop ataxia, spasticity and other neurological symptoms. SCA7 stands out from other SCAs by associating it with retinal dystrophy, causing visual deficiencies that can lead to blindness. Being one of the rarest SCAs, small series of cases appear in the literature. Few of them sought to correlate neurological findings with ophthalmologic findings; and the preclinical stage has never been systematically investigated. Objective: to describe the neurological and ophthalmological findings of a cohort of cases of SCA7, comparing the manifestations found in symptomatic subjects with those found in asymptomatic carriers and in non-carrier relatives in an approach exploratory study that sought to raise potential biomarkers of disease progression. Methods: patients with a molecular diagnosis of SCA7 performed at our institution were identified in our protected files. Both they and their relatives were invited to participate in the present investigation. Subjects at risk of 50% were included if they were older than 18 years. After consent, clinical and demographic data were collected between June 2016 and September 2017. All participants then performed a battery of clinical scales aimed at the measurement of ataxia (SARA, CCFS, PATA and 8 MW) and neurological manifestations (NESSCA and INAS); a visual function questionnaire (NEI-VFQ 25); assessment of better corrected visual acuity (AVMC), mean deviation in computerized campimetry (MD), and thickness of the macula and ganglion cell layer on OCT. The SARA and AVMC scale were chosen as the reference variables for the severity of the frames. Molecular analysis of ATXN7 was done, but study participants and evaluators were kept blind to their results; the individuals at risk interested in receiving their results were sent to the presymptomatic testing program. As there were no a priori criteria for estimating effect sizes and because SCA7 is a rare condition, there was no way to decide on a sample size. The study was exploratory and therefore no corrections were made for multiple tests. A p of 0.05 was chosen to define significance, and statistical tests were applied according to the characteristics of the variables under study. Results: 12 symptomatic carriers (group 2) and 8 individuals at risk (5 carriers - group 1 - and 3 non-carriers - group 0) were included in this study between June 2016 and September 2017. All continuous variables with the exception of CAGexp had normal distribution. AVMC was reduced in all symptomatic participants and clearly different between these and the other two groups (p <0.0001, ANOVA), while asymptomatic and non-carriers had similar results. The mean BCVA was 20/143, 20/18 and 20/20 in groups 2,1 and 6 0, respectively. Not surprisingly, NEI-VFQ 25 also showed a statistically significant difference, but what was unexpected was the progressively different form between the 3 groups (group 0 = 92.76 ± 6.7, group 1 = 74.9 ± 55, 5, group 2 = 58.0 ± 21.3) (p = 0.012, ANOVA with Tukey). The MD showed a statistically significant linear pattern to worsen from the control group (-1.34 ± 1.15dB) to the asymptomatic (-2.81 ± 1.66dB) and from the asymptomatic to the symptomatic group (-10.54 ± 6, 95dB) (p = 0.027, ANOVA with Tukey). In addition, MD correlated with AVMC (p = 0.020; r = 0.660) and showed a correlation tendency with ARDS (p = 0.073; r = -0.535). The macular thickness scores completely distinguish the 3 groups (group 0 = 243.6 ± 22.2 μ, group 1 = 204.5 ± 14.1 μ, group 2 = 137.95 ± 34.6 μ) (p = 0.0001, ANOVA ...) and also correlated significantly with the two planned criteria of severity, SARA (p = 0.050, r = -0.577) and AVMC (p = 0.007, r = 0.730). Conclusion: ophthalmologic changes were present already in the preclinical stages of the disease, when the scores obtained from the neurological scales did not yet distinguish asymptomatic non-carrier patients: macular thickness measured by OCT and MD measured by computerized campimetry. These findings demonstrate that the neurodegenerative process is already underway and is detectable by these anatomical and functional measures of the retina. In addition, both changes detected in preclinical stages, when studied in the total group of symptomatic and asymptomatic carriers, correlated with our gold standard of disease severity, SARA and AVMC. The two findings - pre-clinical onset and correlation with disease progression measured by independent scores - suggest that the macular thickness measured by OCT and MD as measured by computerized campimetry are potential candidates for disease biomarkers (disease progression) from pre-manifest stages in SCA7.
38

Manifestações oftalmológicas e neurológicas em portadores pré-sintomáticos e sintomáticos de ataxia espinocerebelar tipo 7

Azevedo, Pietro Baptista de January 2017 (has links)
Introdução: a ataxia espinocerebelar tipo 7 (SCA7) é um distúrbio neurodegenerativo autossômico dominante causado por uma repetição CAG expandida (CAGexp) no gene ATXN7, resultando na inserção de uma poliglutamina (poliQ) alongada na proteína ataxina-7. Em consequência, pacientes com SCA7 desenvolvem ataxia, espasticidade e outros sintomas neurológicos. A SCA 7 se destaca de outras SCAs por se associar à distrofia retiniana, causando deficiências visuais que podem levar à cegueira. Sendo uma das mais raras SCAs, pequenas séries de casos têm aparecido na literatura. Poucas delas buscaram correlacionar os achados neurológicos com os oftalmológicos; e a fase pré-clínica jamais foi sistematicamente investigada. Objetivo: descrever os achados neurológicos e oftalmológicos de uma coorte de casos de SCA 7, comparando as manifestações encontradas em sujeitos sintomáticos com as encontradas em portadores assintomáticos e em parentes não portadores, em uma abordagem exploratória que buscou levantar potenciais biomarcadores de progressão da doença. Métodos: trata-se de um estudo transversal onde pacientes com diagnóstico molecular de SCA7 realizado na nossa instituição foram identificados em nossos arquivos protegidos. Tanto eles como seus parentes foram convidados a participar da presente investigação. Sujeitos em risco de 50% foram incluídos se tivessem mais de 18 anos. Após o consentimento, dados clínicos e demográficos foram coletados entre junho de 2016 e setembro de 2017. A seguir, todos os participantes realizaram uma bateria de escalas clínicas voltadas à medida da ataxia (SARA, CCFS, PATA e 8 MW) e das manifestações neurológicas (NESSCA e INAS); um questionário de qualidade de vida relacionada à visão (NEI-VFQ 25); avaliação da acuidade visual melhor corrigida (AVMC), desvio médio em campimetria computadorizada (MD) e espessuras da mácula e da camada de células ganglionares na tomografia de coerência óptica (OCT). A escala SARA e a AVMC foram escolhidas como as variáveis de referência para a gravidade dos quadros. A análise molecular do ATXN7 foi feita, mas participantes do estudo e avaliadores foram mantidos cegos para seus resultados; os indivíduos em risco interessados em receber seus resultados foram enviados para o programa de testes pré-sintomáticos. Como não houve critérios a priori para estimar tamanhos de efeito e como a SCA7 é uma condição rara, não houve como decidir um tamanho de amostra. O estudo foi exploratório e por isso não foram feitas correções para múltiplas testagens. Um p de 0,05 foi eleito para definir significância, e testes estatísticos foram aplicados de acordo com as características das variáveis em estudo. Resultados: 12 portadores sintomáticos (grupo 2) e 8 indivíduos em risco (3 portadores - grupo 1 - e 5 não-portadores - grupo 0) foram incluídos neste estudo. Todas as variáveis contínuas à exceção da CAGexp tiveram distribuição 4 normal. A AVMC estava reduzida em todos os participantes sintomáticos e claramente diferente entre estes e os outros dois grupos (p <0,0001, ANOVA), enquanto os portadores assintomáticos e os não portadores tiveram resultados semelhantes. A AVMC média foi 20/143, 20/18 e 20/20 nos grupos 2, 1 e 0, respectivamente. Não surpreendentemente, o NEI-VFQ 25 também demonstrou uma diferença estatisticamente significativa, mas o que foi inesperado foi a forma progressivamente diferente entre os 3 grupos (grupo 0 = 92,76 ± 6,7; grupo 1 = 74,9 ± 55,5; grupo 2 = 58,0 ± 21,3) (p= 0,012, ANOVA com Tukey) O MD mostrou um padrão linear estatisticamente significativo para piorar do grupo controle (-1,34 ± 1,15dB) para o assintomático (-2,81 ± 1,66dB) e do grupo assintomático para sintomático (-10,54 ± 6,95dB) (p = 0,027, ANOVA com Tukey). Além disso, o MD correlacionou-se com a AVMC (p = 0,020; r = 0,660) e apresentou tendência de correlação com a SARA (p= 0,073; r= -0,535). As medidas de espessura macular distinguem completamente os 3 grupos (grupo 0 = 243,6 ± 22,2 μ; grupo 1 = 204,5 ± 14,1 μ; grupo 2 = 137,95 ± 34,6 μ) (p = 0,0001, ANOVA) e também se correlacionou significativamente com os dois critérios planejados de gravidade, SARA (p = 0,050; r = -0,577) e AVMC (p = 0,007; r = 0,730). Discussão: alterações oftalmológicas estavam presentes já nas fases pré-clínicas da doença, quando os escores obtidos das escalas neurológicas ainda não distinguem portadores assintomáticos de não portadores: a espessura macular medida por OCT e o MD medido pela campimetria computadorizada. Esses achados demonstram que o processo neurodegenerativo já se encontra em curso e é detectável por essas medidas anatômicas e funcionais da retina. Além disso, ambas as alterações detectadas em fases pré-clínicas, ao serem estudadas no grupo total de portadores sintomáticos e assintomáticos, se correlacionaram com os nossos padrões-ouro da gravidade da doença, SARA e AVMC. Os dois achados - início em fase pré-clínica e correlação com a progressão da doença medida por escores independentes - sugerem que a espessura macular medida por OCT e o MD medido pela campimetria computadorizada são potenciais candidatos a biomarcadores de estado (de progressão da doença) desde fases pré-manifestas na SCA7. / Background: spinocerebellar ataxia type 7 (SCA7) is an autosomal dominant neurodegenerative disorder caused by an expanded CAG repeat (CAGexp) at ATXN7 gene, resulting in the insertion of an elongated polyglutamine (polyQ) into the ataxin-7 protein. As a consequence, patients with SCA7 develop ataxia, spasticity and other neurological symptoms. SCA7 stands out from other SCAs by associating it with retinal dystrophy, causing visual deficiencies that can lead to blindness. Being one of the rarest SCAs, small series of cases appear in the literature. Few of them sought to correlate neurological findings with ophthalmologic findings; and the preclinical stage has never been systematically investigated. Objective: to describe the neurological and ophthalmological findings of a cohort of cases of SCA7, comparing the manifestations found in symptomatic subjects with those found in asymptomatic carriers and in non-carrier relatives in an approach exploratory study that sought to raise potential biomarkers of disease progression. Methods: patients with a molecular diagnosis of SCA7 performed at our institution were identified in our protected files. Both they and their relatives were invited to participate in the present investigation. Subjects at risk of 50% were included if they were older than 18 years. After consent, clinical and demographic data were collected between June 2016 and September 2017. All participants then performed a battery of clinical scales aimed at the measurement of ataxia (SARA, CCFS, PATA and 8 MW) and neurological manifestations (NESSCA and INAS); a visual function questionnaire (NEI-VFQ 25); assessment of better corrected visual acuity (AVMC), mean deviation in computerized campimetry (MD), and thickness of the macula and ganglion cell layer on OCT. The SARA and AVMC scale were chosen as the reference variables for the severity of the frames. Molecular analysis of ATXN7 was done, but study participants and evaluators were kept blind to their results; the individuals at risk interested in receiving their results were sent to the presymptomatic testing program. As there were no a priori criteria for estimating effect sizes and because SCA7 is a rare condition, there was no way to decide on a sample size. The study was exploratory and therefore no corrections were made for multiple tests. A p of 0.05 was chosen to define significance, and statistical tests were applied according to the characteristics of the variables under study. Results: 12 symptomatic carriers (group 2) and 8 individuals at risk (5 carriers - group 1 - and 3 non-carriers - group 0) were included in this study between June 2016 and September 2017. All continuous variables with the exception of CAGexp had normal distribution. AVMC was reduced in all symptomatic participants and clearly different between these and the other two groups (p <0.0001, ANOVA), while asymptomatic and non-carriers had similar results. The mean BCVA was 20/143, 20/18 and 20/20 in groups 2,1 and 6 0, respectively. Not surprisingly, NEI-VFQ 25 also showed a statistically significant difference, but what was unexpected was the progressively different form between the 3 groups (group 0 = 92.76 ± 6.7, group 1 = 74.9 ± 55, 5, group 2 = 58.0 ± 21.3) (p = 0.012, ANOVA with Tukey). The MD showed a statistically significant linear pattern to worsen from the control group (-1.34 ± 1.15dB) to the asymptomatic (-2.81 ± 1.66dB) and from the asymptomatic to the symptomatic group (-10.54 ± 6, 95dB) (p = 0.027, ANOVA with Tukey). In addition, MD correlated with AVMC (p = 0.020; r = 0.660) and showed a correlation tendency with ARDS (p = 0.073; r = -0.535). The macular thickness scores completely distinguish the 3 groups (group 0 = 243.6 ± 22.2 μ, group 1 = 204.5 ± 14.1 μ, group 2 = 137.95 ± 34.6 μ) (p = 0.0001, ANOVA ...) and also correlated significantly with the two planned criteria of severity, SARA (p = 0.050, r = -0.577) and AVMC (p = 0.007, r = 0.730). Conclusion: ophthalmologic changes were present already in the preclinical stages of the disease, when the scores obtained from the neurological scales did not yet distinguish asymptomatic non-carrier patients: macular thickness measured by OCT and MD measured by computerized campimetry. These findings demonstrate that the neurodegenerative process is already underway and is detectable by these anatomical and functional measures of the retina. In addition, both changes detected in preclinical stages, when studied in the total group of symptomatic and asymptomatic carriers, correlated with our gold standard of disease severity, SARA and AVMC. The two findings - pre-clinical onset and correlation with disease progression measured by independent scores - suggest that the macular thickness measured by OCT and MD as measured by computerized campimetry are potential candidates for disease biomarkers (disease progression) from pre-manifest stages in SCA7.
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Manifestações oftalmológicas e neurológicas em portadores pré-sintomáticos e sintomáticos de ataxia espinocerebelar tipo 7

Azevedo, Pietro Baptista de January 2017 (has links)
Introdução: a ataxia espinocerebelar tipo 7 (SCA7) é um distúrbio neurodegenerativo autossômico dominante causado por uma repetição CAG expandida (CAGexp) no gene ATXN7, resultando na inserção de uma poliglutamina (poliQ) alongada na proteína ataxina-7. Em consequência, pacientes com SCA7 desenvolvem ataxia, espasticidade e outros sintomas neurológicos. A SCA 7 se destaca de outras SCAs por se associar à distrofia retiniana, causando deficiências visuais que podem levar à cegueira. Sendo uma das mais raras SCAs, pequenas séries de casos têm aparecido na literatura. Poucas delas buscaram correlacionar os achados neurológicos com os oftalmológicos; e a fase pré-clínica jamais foi sistematicamente investigada. Objetivo: descrever os achados neurológicos e oftalmológicos de uma coorte de casos de SCA 7, comparando as manifestações encontradas em sujeitos sintomáticos com as encontradas em portadores assintomáticos e em parentes não portadores, em uma abordagem exploratória que buscou levantar potenciais biomarcadores de progressão da doença. Métodos: trata-se de um estudo transversal onde pacientes com diagnóstico molecular de SCA7 realizado na nossa instituição foram identificados em nossos arquivos protegidos. Tanto eles como seus parentes foram convidados a participar da presente investigação. Sujeitos em risco de 50% foram incluídos se tivessem mais de 18 anos. Após o consentimento, dados clínicos e demográficos foram coletados entre junho de 2016 e setembro de 2017. A seguir, todos os participantes realizaram uma bateria de escalas clínicas voltadas à medida da ataxia (SARA, CCFS, PATA e 8 MW) e das manifestações neurológicas (NESSCA e INAS); um questionário de qualidade de vida relacionada à visão (NEI-VFQ 25); avaliação da acuidade visual melhor corrigida (AVMC), desvio médio em campimetria computadorizada (MD) e espessuras da mácula e da camada de células ganglionares na tomografia de coerência óptica (OCT). A escala SARA e a AVMC foram escolhidas como as variáveis de referência para a gravidade dos quadros. A análise molecular do ATXN7 foi feita, mas participantes do estudo e avaliadores foram mantidos cegos para seus resultados; os indivíduos em risco interessados em receber seus resultados foram enviados para o programa de testes pré-sintomáticos. Como não houve critérios a priori para estimar tamanhos de efeito e como a SCA7 é uma condição rara, não houve como decidir um tamanho de amostra. O estudo foi exploratório e por isso não foram feitas correções para múltiplas testagens. Um p de 0,05 foi eleito para definir significância, e testes estatísticos foram aplicados de acordo com as características das variáveis em estudo. Resultados: 12 portadores sintomáticos (grupo 2) e 8 indivíduos em risco (3 portadores - grupo 1 - e 5 não-portadores - grupo 0) foram incluídos neste estudo. Todas as variáveis contínuas à exceção da CAGexp tiveram distribuição 4 normal. A AVMC estava reduzida em todos os participantes sintomáticos e claramente diferente entre estes e os outros dois grupos (p <0,0001, ANOVA), enquanto os portadores assintomáticos e os não portadores tiveram resultados semelhantes. A AVMC média foi 20/143, 20/18 e 20/20 nos grupos 2, 1 e 0, respectivamente. Não surpreendentemente, o NEI-VFQ 25 também demonstrou uma diferença estatisticamente significativa, mas o que foi inesperado foi a forma progressivamente diferente entre os 3 grupos (grupo 0 = 92,76 ± 6,7; grupo 1 = 74,9 ± 55,5; grupo 2 = 58,0 ± 21,3) (p= 0,012, ANOVA com Tukey) O MD mostrou um padrão linear estatisticamente significativo para piorar do grupo controle (-1,34 ± 1,15dB) para o assintomático (-2,81 ± 1,66dB) e do grupo assintomático para sintomático (-10,54 ± 6,95dB) (p = 0,027, ANOVA com Tukey). Além disso, o MD correlacionou-se com a AVMC (p = 0,020; r = 0,660) e apresentou tendência de correlação com a SARA (p= 0,073; r= -0,535). As medidas de espessura macular distinguem completamente os 3 grupos (grupo 0 = 243,6 ± 22,2 μ; grupo 1 = 204,5 ± 14,1 μ; grupo 2 = 137,95 ± 34,6 μ) (p = 0,0001, ANOVA) e também se correlacionou significativamente com os dois critérios planejados de gravidade, SARA (p = 0,050; r = -0,577) e AVMC (p = 0,007; r = 0,730). Discussão: alterações oftalmológicas estavam presentes já nas fases pré-clínicas da doença, quando os escores obtidos das escalas neurológicas ainda não distinguem portadores assintomáticos de não portadores: a espessura macular medida por OCT e o MD medido pela campimetria computadorizada. Esses achados demonstram que o processo neurodegenerativo já se encontra em curso e é detectável por essas medidas anatômicas e funcionais da retina. Além disso, ambas as alterações detectadas em fases pré-clínicas, ao serem estudadas no grupo total de portadores sintomáticos e assintomáticos, se correlacionaram com os nossos padrões-ouro da gravidade da doença, SARA e AVMC. Os dois achados - início em fase pré-clínica e correlação com a progressão da doença medida por escores independentes - sugerem que a espessura macular medida por OCT e o MD medido pela campimetria computadorizada são potenciais candidatos a biomarcadores de estado (de progressão da doença) desde fases pré-manifestas na SCA7. / Background: spinocerebellar ataxia type 7 (SCA7) is an autosomal dominant neurodegenerative disorder caused by an expanded CAG repeat (CAGexp) at ATXN7 gene, resulting in the insertion of an elongated polyglutamine (polyQ) into the ataxin-7 protein. As a consequence, patients with SCA7 develop ataxia, spasticity and other neurological symptoms. SCA7 stands out from other SCAs by associating it with retinal dystrophy, causing visual deficiencies that can lead to blindness. Being one of the rarest SCAs, small series of cases appear in the literature. Few of them sought to correlate neurological findings with ophthalmologic findings; and the preclinical stage has never been systematically investigated. Objective: to describe the neurological and ophthalmological findings of a cohort of cases of SCA7, comparing the manifestations found in symptomatic subjects with those found in asymptomatic carriers and in non-carrier relatives in an approach exploratory study that sought to raise potential biomarkers of disease progression. Methods: patients with a molecular diagnosis of SCA7 performed at our institution were identified in our protected files. Both they and their relatives were invited to participate in the present investigation. Subjects at risk of 50% were included if they were older than 18 years. After consent, clinical and demographic data were collected between June 2016 and September 2017. All participants then performed a battery of clinical scales aimed at the measurement of ataxia (SARA, CCFS, PATA and 8 MW) and neurological manifestations (NESSCA and INAS); a visual function questionnaire (NEI-VFQ 25); assessment of better corrected visual acuity (AVMC), mean deviation in computerized campimetry (MD), and thickness of the macula and ganglion cell layer on OCT. The SARA and AVMC scale were chosen as the reference variables for the severity of the frames. Molecular analysis of ATXN7 was done, but study participants and evaluators were kept blind to their results; the individuals at risk interested in receiving their results were sent to the presymptomatic testing program. As there were no a priori criteria for estimating effect sizes and because SCA7 is a rare condition, there was no way to decide on a sample size. The study was exploratory and therefore no corrections were made for multiple tests. A p of 0.05 was chosen to define significance, and statistical tests were applied according to the characteristics of the variables under study. Results: 12 symptomatic carriers (group 2) and 8 individuals at risk (5 carriers - group 1 - and 3 non-carriers - group 0) were included in this study between June 2016 and September 2017. All continuous variables with the exception of CAGexp had normal distribution. AVMC was reduced in all symptomatic participants and clearly different between these and the other two groups (p <0.0001, ANOVA), while asymptomatic and non-carriers had similar results. The mean BCVA was 20/143, 20/18 and 20/20 in groups 2,1 and 6 0, respectively. Not surprisingly, NEI-VFQ 25 also showed a statistically significant difference, but what was unexpected was the progressively different form between the 3 groups (group 0 = 92.76 ± 6.7, group 1 = 74.9 ± 55, 5, group 2 = 58.0 ± 21.3) (p = 0.012, ANOVA with Tukey). The MD showed a statistically significant linear pattern to worsen from the control group (-1.34 ± 1.15dB) to the asymptomatic (-2.81 ± 1.66dB) and from the asymptomatic to the symptomatic group (-10.54 ± 6, 95dB) (p = 0.027, ANOVA with Tukey). In addition, MD correlated with AVMC (p = 0.020; r = 0.660) and showed a correlation tendency with ARDS (p = 0.073; r = -0.535). The macular thickness scores completely distinguish the 3 groups (group 0 = 243.6 ± 22.2 μ, group 1 = 204.5 ± 14.1 μ, group 2 = 137.95 ± 34.6 μ) (p = 0.0001, ANOVA ...) and also correlated significantly with the two planned criteria of severity, SARA (p = 0.050, r = -0.577) and AVMC (p = 0.007, r = 0.730). Conclusion: ophthalmologic changes were present already in the preclinical stages of the disease, when the scores obtained from the neurological scales did not yet distinguish asymptomatic non-carrier patients: macular thickness measured by OCT and MD measured by computerized campimetry. These findings demonstrate that the neurodegenerative process is already underway and is detectable by these anatomical and functional measures of the retina. In addition, both changes detected in preclinical stages, when studied in the total group of symptomatic and asymptomatic carriers, correlated with our gold standard of disease severity, SARA and AVMC. The two findings - pre-clinical onset and correlation with disease progression measured by independent scores - suggest that the macular thickness measured by OCT and MD as measured by computerized campimetry are potential candidates for disease biomarkers (disease progression) from pre-manifest stages in SCA7.

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