Foram avaliados 50 pacientes com esquizofrenia, através de escalas e de Ressonância magnética, feita também em 30 controles normais. Foi observado maior grau de comprometimento da crítica em pacientes não ocupados e que recebiam associação de antipsicóticos. Foi encontrada correlação positiva entre maior comprometimento da crítica e mais desorganização, excitação, hostilidade e total de sintomas negativos, além de correlação negativa com ansiedade, sentimento de culpa e depressão. Houve correlação entre comprometimento da crítica e diminuição do volume de substância cinzenta no giro lingual no lobo occipital, que não se manteve após correção para comparações múltiplas. Foi observada atrofia de substância cinzenta em área de 27 cm3 em insula, lobos frontal, temporal e parietal, nos pacientes com esquizofrenia / Fifth patients with schizophrenia were evaluated with psychopathological and insight scales and cerebral magnetic ressonance (made also on thirty normal controls). There was a greater insight impairment on unemployed patients and on these receiving two or more antipsychotics. There was a positive correlation between greater insight impairment and disorganization, excitation, hostility and total negative symptoms, besides a negative correlation with anxiety, guilt feelings, preoccupation and depression. Patients with less insight had a reduction of gray matter volume on the lingual gyrus, occipital lobe, that disappeared when correction for multiple comparisons was made. Schizophrenic patients had gray matter reduction in an 27 cm3 area in insula and frontal, temporal and parietal lobes

Lee, Kar Ho Francis. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 148-163). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

Tsang, Man Ho. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 57-60). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese.

The interplay between sounds and movements is not only critical for music performance, but also for the acquisition of speech, and might underlie the success of using music as a therapeutic tool in the facilitation of movements. This dissertation is comprised of three functional magnetic resonance imaging studies that aim to elucidate the neural basis underlying interactions between the auditory and motor systems in the context of musical rhythm perception and production. Study 1 investigated the neural correlates that facilitate auditory-motor coupling while subjects tapped along with an isochronous rhythm. Auditory input was manipulated so that the metric saliency of the isochronous rhythm increased across five parametric levels in order to modulate subjects’ tapping behaviour. [...] / L’interaction entre le son et le mouvement n’est pas seulement essentielle lors de prestations musicales, mais aussi lors de l’ acquisition de la parole, et pourrait être à la base du succès de la musique lorsqu’elle est utilisée en tant qu’agent thérapeutique visant la facilitation du mouvement. Cette dissertation consiste en trois études d’imagerie par résonance magnétique fonctionnelle visant à élucider les fondements neuraux à la base de l’interaction entre le système auditif et le système moteur dans le contexte de la perception et de la production de rythmes musicaux. La première étude examina les corrélats neuraux facilitant le couplage auditif-moteur chez des sujets produisant des battements alors qu’ils étaient guidés par un rythme isochronique. L’information auditive fut manipulée pour que la proéminence métrique du rythme isochronique augmente à travers cinq niveaux paramétriques dans le but de moduler les battements produits par le sujet. [...]

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O método mais eficaz para detecção de carcinoma mamário ductal in situ é a mamografia, que apesar de apresentar alta sensibilidade, possui baixa especificidade e não demonstra todos os casos deste tipo de lesão. Assim sendo, pesquisadores têm desenvolvido modalidades por imagem adjuntas à mamografia, das quais a mais promissora talvez seja a ressonância magnética mamária de alta resolução. Neste estudo investigou-se a capacidade da ressonância magnética, realizada em aparelho de 1,5 Tesla, com gradientes de alto desempenho, uso de bobina de superfície dedicada para mama e agente paramagnético por via endovenosa, em demonstrar focos de carcinoma ductal in situ em sua forma pura. Realizou-se análise retrospectiva em 24 pacientes que apresentaram este diagnóstico histológico e haviam sido submetidas à mamografia e à ressonância magnética. Evidenciou-se baixa reprodutibilidade entre os achados mamográficos e os da ressonância magnética mamaria, com discordância em 13 dos 24 casos (54%). Mesmo assim, concluiu-se que a ressonância magnética mamária foi valiosa, pois apesar de ter sido negativa em 5 dos 16 casos mamograficamente detectados (20,83%) revelou 8 focos de carcinoma ductal in situ não vistos à mamografia (33,33%), contribuindo de modo decisivo para o planejamento terapêutico destas pacientes. / Mammography is the most effective method to detect ductal carcinoma in situ of the breast. However, despite its high sensitivity, its specificity is low and some foci of ductal carcinoma in situ may not be detected by it. This fact has encouraged researchers to develop imaging methods adjunctive to mammography of which high resolution magnetic resonance imaging is perhaps the most promising. The purpose of this study is to investigate the ability of magnetic resonance imaging, performed in a 1.5 Tesla system with high performance gradients, the use of breast dedicated surface coil and intravenous paramagnetic agent to demonstrate foci of pure ductal carcinoma in situ. Retrospective analysis was performed to the examinations of 24 patients with this pathologic diagnosis that have been subjected to both mammography and breast magnetic resonance imaging. This study revealed that the concordance rates between mammography and magnetic resonance imaging provided low reprodutibility, being discordant in 13 of the 24 cases (54%). However, we concluded that breast magnetic resonance imaging was valuable because, despite of not depicting 5 of 16 mammographically detected cases (20,83%), it was able to detect 8 foci of ductal carcinoma in situ exclusively (33,33%), contributing to the therapeutic planning for these patients.

Avaliar por ressonância magnética (IRM), placa e remodelamento coronários, comparar estenose por IRM e cinecoronariografia (CINE) e correlacionar achados de US de carótidas em pacientes (pts) com DAC. Avaliamos 10 controles(ctls) e 26 pts (lesão > 50% à CINE). Realizamos cortes transversais em artérias DA e CD (2Dblack-blood). Calculamos espessamento parietal (EP), área luminal (AL), área da parede (AP) e área total do vaso (ATV). Detectamos significantes aumentos em EP, AP e ATV nos pts vs. ctls, sem diferenças quanto a AL. Ajustando AL pela ATV, houve redução desta relação nos pts vs. ctls (remodelamento positivo). Em conclusão, a IRM identifica a parede e remodelamento de coronárias em pts com DAC, não houve correlação entre IRM e CINE quanto à estenose e placa em carótidas foi mais prevalente nos pts / To test magnetic resonance imaging (MRI) in detecting atherosclerotic plaque and coronary remodeling in patients (pts) with CAD, to compare stenosis grade (MRI vs. angiography), and to correlate carotid plaque by US and CAD. Cross-sectional slices (2D black-blood) was performed in LAD and RCA in 10 controls (ctls) and 26 pts ( > 50% stenosis) by MRI. Maximum wall thickness (WT), vessel wall area (VWA), luminal area (LA) and total vessel area (TVA) were analyzed. MRI detected increases in WT, VWA and TVA in pts vs. ctls, but not for LA. Adjusting LA for TVA, reduction was found in pts (positive remodeling). In conclusion, MRI allowed vessel abnormalities and coronary remodeling in pts with CAD, there was no correlation between stenosis grade (MRI vs. angiography) and carotid plaque was more prevalent in pts

O objetivo da reperfusão mecânica ou medicamentosa em pacientes com infarto agudo do miocárdio (IAM) é a restauração do fluxo sangüíneo na artéria relacionada ao infarto, a fim de limitar a necrose miocelular e preservar a função contrátil, que são os maiores preditores de sobrevida após o IAM. Entretanto, seu sucesso é indicado pela reperfusão nos capilares miocárdicos e não pela recanalização da artéria relacionada ao infarto. A ecocardiografia com perfusão miocárdica em tempo real pode ser usada para avaliar a perfusão nos capilares miocárdicos e estimar o tamanho do infarto em vários estudos experimentais. O objetivo deste estudo foi determinar a área do miocárdio infartado e sua extensão transmural pela ecocardiografia com perfusão miocárdica em tempo real, em pacientes hospitalizados nos primeiros dias após primo infarto agudo do miocárdio, tendo como padrão de referência a ressonância magnética de perfusão. Prospectivamente, foram estudados 20 pacientes (12 homens), com idade média de 64,2 ± 13,3, dentro de 12 horas de reperfusão mecânica ou medicamentosa. Os exames de ecocardiografia e ressonância magnética foram realizados do segundo ao quinto dia de infarto. O contraste \"PESDA (perfluorocarbon-exposed sonicated dextrose albumin)\" foi administrado em veia periférica, na dose de 0,1ml/Kg, em infusão contínua. A análise ecocardiográfica foi feita por uma análise qualitativa (visual) denominada escala de cinza e por uma análise quantitativa, chamada imagem paramétrica. A área de infarto média foi de 3,03 ± 2,77 cm2 para a escala de cinza (r=0,97), de 3,36 ± 2,82 cm2 para a imagem paramétrica (r= 0,99) e de 3,42 ± 2,80 cm2 para a ressonância magnética. O porcentual médio da área de infarto pela ecocardiografia em escala de cinza foi de 15,22% ± 14,84% (r= 0,97), pela imagem paramétrica foi de 16,46% ± 14,41% (r= 0,99) e pela ressonância magnética foi de 16,76% ± 14,48%. A extensão transmural do infarto em cada segmento infartado pela escala de cinza,apresentou uma correlação menor (r=0,77) em relação à imagem paramétrica (r=0,93). Em conclusão, este estudo mostrou uma excelente correlação entre ecocardiografia com perfusão miocárdica em tempo real (sobretudo pela imagem paramétrica) e ressonância magnética nas medidas da área de infarto e seu porcentual, assim como na determinação de sua extensão transmural em pacientes internados por infarto agudo do miocárdio / The aim of mechanical or pharmacological reperfusion in patients with AMI is to restore blood flow through the infarct related artery in order to limit myocellular necrosis and ultimately preserve myocardial contractile function, which is still the most powerful predictor of survival after acute myocardial infarction. The success of reperfusion, however, is indicated by perfusion of myocardial capillaries rather than simply patency of the infarct related artery. Myocardial contrast echocardiography (MCE) can be used to assess myocardial capillary perfusion and ultimately the infarct size in animals. The aim of this study was to determine by MCE the transmural extent and infarct size using magnetic resonance imaging (MRI) as a gold standard. We prospectively studied 20 patients (12 men; mean age 64.2 ± 13.3) admitted for a first acute myocardial infarction, within 12 hours after mechanical or pharmacological reperfusion. The MCE and MRI were performed between the 3rd and 5th day of acute myocardial infarction (AMI). A suspension of 0.1 ml/kg of perfluorocarbon-exposed sonicated dextrose albumin (PESDA) ultrasound contrast agent was administered as a continuous infusion. The interpretation of perfusion images by MCE was assessed by qualitative analysis (visual- VIS) and a quantitative one called parametric image (PI). The average infarct area showed by VIS was 3.03 ± 2.77 cm 2, by PI was 3.36 ± 2.82 cm 2 and by MRI was 3.42± 2.80cm 2. The average percentage of infarct area by VIS was 15.22% ± 14.84%, by PI was 16.46% ± 14.41% and by MRI was 16.76% ± 14.48%. The transmural extent was calculated in each infarcted segment by VIS, with a worse correlation (r=0,77) than PI (r=0,93). In conclusion, this study showed that MCE, in special PI, correlates well with MRI in detecting infarct size, percentage of infarct size and transmural extent in patients with acute myocardial infarction

無線膠囊內窺鏡（CE）是一種用於檢查整個胃腸道，尤其是小腸的無創技術。它極大地改善了許多小腸疾病的診斷和管理方式，如不明原因的消化道出血，克羅恩病，小腸腫瘤，息肉綜合征等。儘管膠囊內窺鏡有很好的臨床表現，但它仍然有一定的局限性。主要問題是每次檢查產生約50,000 幅低質量的圖像，對於醫生來說，評估如此大量的圖像是一項非常耗時、耗力的工作。 / 到目前為止，對於膠囊內窺鏡的分析和評估，學者們都把膠囊內窺鏡圖像視為單獨的，獨立的觀測對象。事實並非如此，因為圖像之間往往有顯著的重疊。特別是當膠囊內窺鏡在被小腸蠕動緩緩推動時，它可以捕捉同一病灶的多個視圖。我們的研究目的是使用所有可用的資訊，包括多幅圖像，研究對於膠囊內窺鏡的電腦輔助診斷（CAD）系統。 / 在這篇論文中，我們提出了一個嵌入分類器的多類隱馬爾可夫模型（HMM）的方案，它可以融合多幅相鄰圖像的時間資訊。由於膠囊內窺鏡圖像的品質比較低，我們首先進行預處理，以加強膠囊內窺鏡圖像，增加其對比度，消除噪聲。我們調查研究了多種圖像增強的方法，並調整了它們的參數使其適用於膠囊內窺鏡圖像。 / 對於基於單幅圖像的有監督的分類，AdaBoost 作為一個集成分類器來融合多個分類器，即本論文中的支持向量機（SVM），k-近鄰（k-NN），貝葉斯分類。在分類之前，我們提取和融合了顏色，邊緣和紋理特徵。 / 對於無線膠囊內窺鏡的視頻摘要，我們提出了有監督和無監督的兩類方法。對於有監督方法，我們提出了一個基於隱馬爾可夫模型的，靈活的，可擴展的框架，用於整合膠囊內窺鏡中連續圖像的時間資訊。它可以擴展到多類別，多特徵，多狀態。我們還提出了聯合隱馬爾可夫模型和並行隱馬爾可夫（PHMM）模型對系統進行改進，它們可以被看作是決策級的資訊融合。聯合隱馬爾可夫模型通過多層次的隱馬爾可夫模型，結合不同的資訊來源，對膠囊內窺鏡視頻進行分類和視頻摘要。 並行隱馬爾可夫模型採用貝葉斯推理，在決策時融合多個不同來源的資訊。對於無監督的方法，我們首先提出了一種基於顏色的特徵提取方法。在反色顏色空間中對亮度不變的色度不變矩用來表示膠囊內窺鏡圖像的顏色特徵。接著，我們又提出了一種基於輪廓元（Contourlet）變換的局部二元模式（LBP）作為紋理特徵。在特徵空間中，我們測量了相鄰圖像的距離，並把它視為一個位於二維平面上的開放輪廓上的點。 然後，我們採用一個無參數的關鍵點檢測方法檢測在視頻片段上的突變關鍵點。基於這些突變關鍵點，我們對膠囊內窺鏡視頻進行分割。最後，在每段被分割的視頻片段上，我們通過提取有代表性的關鍵幀來實現膠囊內窺鏡視頻摘要。我們分別用模擬和真實的病人數據進行實驗，對提出的方法進行驗證，結果表明了我們所提出的方案的有效性。它在實現自動評估膠囊內窺鏡圖像上具有很大的潛力。 / Wireless Capsule Endoscopy (CE) is a non-invasive technology to inspect the whole gastrointestinal (GI) tract, especially the small intestine. It has dramatically changed the way of diagnosis and management of many diseases of the small intestine, such as obscure gastrointestinal bleeding, Crohn’s disease, small bowel tumors, polyposis syndromes, etc. Despite its promising clinical findings, it still has some limitations. The main problem is that it requires manual assessment of approximately 50,000 low quality images per examination which is highly time-consuming and labor-intense. / CE analysis and assessment so far treated CE images as individual and independent observations. It is obviously not the case as there is often significant overlap among images. In particular, CE captures multiple views of the same anatomy as the capsule is slowly propelled by peristalsis. Our broader work aims to perform computer aided diagnosis (CAD) in endoscopy using all available information, including multiple images. / In this dissertation, a framework of multi-class Hidden Markov Models (HMM) embedded with statistical classifiers for combining information from multiple CE images is proposed. Due to the low quality of CE image, pre-processing is performed to enhance CE images by increasing the contrast and removing noises. Several image enhancement methods are investigated and customized for CE images. For frame-based supervised classification, AdaBoost is used as the ensemble classifier to combine multiple classifiers, i.e. support vector machine (SVM), k-nearest neighbor (k-NN), and Bayes classifier. Before classification, color, edge and texture features are extracted and fused. Finally, both supervised and unsupervised methods are proposed for CE study synopsis. For supervised method, a flexible and extensible framework based on HMM is developed to integrate temporal information in CE images. It can be extended to multi-class, multi-features, and multi-states. Improvements can be made by combined HMM and Parallel HMM (PHMM) which are introduced as decision-level fusion schemes. Combined HMM considers different sources via a multi-layer HMM model to perform classification and video synopsis. PHMM employs Bayesian inference to combine the recognition results at decision level. For unsupervised method, illumination-independent opponent color moment invariants and local binary pattern (LBP) based on Contourlet transform are explored as color and texture features, respectively. Pair-wise image dissimilarity is measured in the feature space and treated as points on an open contour in a 2-D plane. CE video is segmented based on sudden change points which are detected using a non-parametric key-point detection method. From each segment, representative frames are extracted to summarize the CE video. Validation results on simulated and real patient data show promising performance of the proposed framework. It has great potential to achieve automatic assessment for CE images. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Zhao, Qian. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 142-175). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Abstract --- p.ii / Acknowledgments --- p.vii / List of Tables --- p.xiii / List of Figures --- p.xv / Chapter 1 --- The Relevance of Synopsis --- p.1 / Chapter 1.1 --- Problem Statement --- p.1 / Chapter 1.2 --- Application - Capsule Endoscopy Assessment --- p.4 / Chapter 1.3 --- Literature Review --- p.9 / Chapter 1.3.1 --- Methods Based on Frame Classification --- p.11 / Chapter 1.3.2 --- Methods Integrating Temporal Information --- p.14 / Chapter 1.4 --- Contributions --- p.19 / Chapter 1.5 --- Organization --- p.23 / Chapter 2 --- Preliminary --- p.25 / Chapter 2.1 --- Hidden Markov Model (HMM) --- p.25 / Chapter 2.2 --- Factorial HMM --- p.35 / Chapter 3 --- Temporal Integration in Capsule Endoscopy Image Analysis --- p.37 / Chapter 3.1 --- Pre-processing --- p.38 / Chapter 3.2 --- Feature Extraction --- p.43 / Chapter 3.3 --- Frame-based Supervised Classification --- p.47 / Chapter 3.3.1 --- Supervised Classification using Individual Frames --- p.47 / Chapter 3.3.2 --- Ensemble Learning Based on AdaBoost --- p.50 / Chapter 3.4 --- Sequence-based Supervised Classification --- p.52 / Chapter 3.5 --- Experiments --- p.58 / Chapter 3.5.1 --- Capsule Endoscopy Image Enhancement --- p.60 / Chapter 3.5.2 --- Frame-based Supervised Classification --- p.67 / Chapter 3.5.3 --- Image Sequence Classification --- p.68 / Chapter 3.6 --- Discussion --- p.80 / Chapter 3.7 --- Summary --- p.82 / Chapter 4 --- Capsule Endoscopy Study Synopsis --- p.98 / Chapter 4.1 --- Supervised Synopsis Using Statistical Models --- p.98 / Chapter 4.2 --- Unsupervised Synopsis via Representative Frame Extraction --- p.100 / Chapter 4.2.1 --- Feature Extraction --- p.100 / Chapter 4.2.2 --- Non-parametric Key-point Detection --- p.111 / Chapter 4.2.3 --- Representative Frame Extraction --- p.112 / Chapter 4.3 --- Experiments --- p.119 / Chapter 4.3.1 --- Supervised Synopsis Based on HMM --- p.119 / Chapter 4.3.2 --- Unsupervised Synopsis --- p.125 / Chapter 4.4 --- Discussion --- p.132 / Chapter 4.5 --- Summary --- p.133 / Chapter 5 --- Conclusions and Future Work --- p.138 / Chapter 5.1 --- Conclusions --- p.138 / Chapter 5.2 --- Future Work --- p.141 / Bibliography --- p.142

Hipotrofía nos músculos que estabilizam a coluna tem sido identificada nos pacientes com lombalgia. Entretanto, não se sabe se a perda muscular é causa ou conseqüência desta disfunção, nem se ela é influenciada pelo tipo de alteração discal que o indivíduo apresenta. Este estudo testou a hipótese de que a hipotrofía dos pacientes com lombalgia seja dependente do tipo de alteração discal. Para avaliar a condição muscular em diferentes tipos de alteração discal, optou-se por um estudo retrospectivo e por uma seleção aleatória de 78 exames de ressonância magnética de indivíduos com lombalgia. Em cada exame foram realizadas medidas quantitativas da porcentagem de gordura na área de secção transversa dos mm. multífidus e psoas, nos três últimos níveis da coluna lombar. A alteração discal foi encontrada em 95% dos exames, sendo o abaulamento o achado de imagem mais freqüente, seguido pela protrusão discal. A porcentagem de gordura variou conforme o tipo de alteração discal. Nos níveis com abaulamento há em ambos os músculos estudados 6% a mais de tecido gorduroso do que nos níveis onde há protrusão e esta diferença foi estatisticamente significante. Músculos nos níveis onde há protrusão sem fissura no anel fibroso apresentaram maior substituição gordurosa do que aqueles onde há protrusão com fissura. A porcentagem de gordura foi influenciada por características anatômicas como músculo estudado e nível da coluna, e por características como idade e sexo dos sujeitos. Estes resultados indicam que a hipotrofía muscular em pacientes com lombalgia não é um processo uniforme e generalizado, mas sim correlacionado a diferentes variáveis, entre elas o tipo de alteração discal que o paciente apresenta. / Low back pain patients present atrophy on muscles responsible for spine stabilization. However, it is not clear if muscle waste is related to the cause or if it is a consequence of this disfunction. Nor it is clear if muscle athophy is affected by the type of disc pathology. This study tested the hypothesis that muscle waste in low back pain patients influenced by the type of disc derangement. Magnetic resonance scans of 78 low back pain patients were randomly analysed. Cross sectional area percentage of fat tissue in multifidi and psoas major muscles was measured on the lower levels of the lumbar spine. Disc pathology was found in 95% of the exams and disc bulge was the most frequent abnormality, followed by disc protrusion. Fat percentage varied according to disc pathology and this difference was statistically significant. Muscles on levels with disc bulge presented 6% more fat deposits than muscles on levels with disc protrusion. Muscles on levels with discs without anular tear present more fat infiltration than muscles on levels with anular tear. Fat percentage was also influenced by anatomic aspects such as evaluated muscle and spine level, and sample characteristics as age and sex. The results indicated that muscle atrophy in low back pain patients is not a uniform and generalized feature. It is correlated to different variables, such as type of disc pathology