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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.
21

Is incision and drainage necessary following endodontic debridement?

Kotapish, Matthew James January 2020 (has links)
No description available.
22

Incidence and severity of Arcanobacterium pyogenes injection site abscesses with needle and needle-free injection methods

Gerlach, Bryce Mark January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Terry A. Houser / Nursery age pigs (n=198) were used to evaluate the difference in the occurrence of injection site abscesses between needle-free jet injection and conventional needle-and-syringe injection systems. Pigs were fed for 21 d prior to treatment administration to acclimate the pigs to the environment of the Kansas State University Segregated Early Weaning (SEW) unit. On d 21 each pig was injected with aluminum hydroxide adjuvant in the neck and ham with needle-free jet injection (Pulse Needle-Free Systems, Lenexa, KS) and conventional needle-and-syringe injection. Needle-free and conventional needle-and-syringe injections were randomly assigned to pig side yielding a total of 396 injections per treatment with a total of 792 injections sites. Immediately prior to injection, the external surface of the injection sites were contaminated with an inoculum of Arcanobacterium pyogenes, a bacterium commonly associated with livestock abscesses. The pigs were then fed for a period of 27 or 28 d. On d 27 or d 28 the pigs were humanely euthanized and sent to the Kansas State Veterinary Diagnostics Laboratory where necropsies were performed and the injection sites harvested for histopathological evaluation. The needle-free jet injection system was associated with more injection site abscesses than the conventional needle-and-syringe injection method for both neck (P=0.0625) and ham (P=0.0313) injection sites. Twelve abscesses were found at injection sites administered via needle-free jet injection method while only 1 abscess was found with the conventional needle-and-syringe injection method. 5 abscesses were found at the neck injection sites and 8 abscesses were found at ham injection sites. There were no significant differences seen in tissue granulation resulting from reaction to the adjuvant. In summary, the implementation of needle-free jet injection systems in market hog production will be beneficial to eliminate needles and needle fragments in meat products but, when in the presence of Arcanobacterium pyogenes, it may increase the occurrence of injection site abscesses in pork carcasses that will need to be trimmed in pork processing plants. Although more abscesses were associated with needle-free jet injection, their occurrence was observed at a very low rate given that all injection sites were intentionally contaminated prior to injection.
23

Cadaver-based abscess model for medical training

Ellis, Michael, Nelson, Joseph, Kartchner, Jeffrey, Yousef, Karl, Adamas-Rappaport, William, Amini, Richard 01 1900 (has links)
Ultrasound imaging is a rapid and noninvasive tool ideal for the imaging of soft tissue infections and is associated with a change of clinician management plans in 50% of cases. We developed a realistic skin abscess diagnostic and therapeutic training model using fresh frozen cadavers and common, affordable materials. Details for construction of the model and suggested variations are presented. This cadaver-based abscess model produces high-quality sonographic images with internal echogenicity similar to a true clinical abscess, and is ideal for teaching sonographic diagnostic skills in addition to the technical skills of incision and drainage or needle aspiration.
24

Psoas abscess secondary to retroperitoneal distant metastases from squamous cell carcinoma of the cervix with thrombosis of the inferior vena cava and duodenal infiltration treated by Whipple procedure

Mehdorn, Matthias, Petersen, Tim-Ole, Bartels, Michael, Jansen-Winkeln, Boris, Kassahun, Woubet Tefera 06 September 2016 (has links) (PDF)
Background: Psoas abscess is a rare clinical disease of various origins. Most common causes include hematogenous spread of bacteria from a different primary source, spondylodiscitis or perforated intestinal organs. But rarely some abscesses are related to malignant metastatic disease. Case presentation: In this case report we present the case of a patient with known squamous cell carcinoma of the cervix treated with radio-chemotherapy three years prior. She now presented with a psoas abscess and subsequent complete inferior vena cava thrombosis, as well as duodenal and vertebral infiltration. The abscess was drained over a prolonged period of time and later was found to be a complication caused by metastases of the cervical carcinoma. Due to the massive extent of the metastases a Whipple procedure was performed to successfully control the local progress of the metastasis. Conclusion: As psoas abscess is an unspecific disease which presents with non-specific symptoms adequate therapy may be delayed due to lack of early diagnostic results. This case report highlights the difficulties of managing a malignant abscess and demonstrates some diagnostic pitfalls that might be encountered. It stresses the necessity of adequate diagnostics to initiate successful therapy. Reports on psoas abscesses that are related to cervix carcinoma are scarce, probably due to the rarity of this event, and are limited to very few case reports. We are the first to report a case in which an extensive and complex abdominal procedure was needed for local control to improve quality of life.
25

Anticorpos policlonais e monensina sódica na alimentação de bovinos jovens confinados com dietas de alto concentrado /

Millen, Danilo Domingues, 1981- January 2010 (has links)
Orientador: Mário De Beni Arrigoni / Banca: Telma Terezinha Berchielli / Banca: Mário Sartori Bueno / Banca: Rafael da Costa Cervieri / Banca: José Roberto Sartori / Resumo: O objetivo deste estudo foi estudar os efeitos da suplementação do preparado de anticorpos policlonais (PAP) ou monensina sódica (MON) sobre o desempenho, características de carcaça, perfil metabólico sanguíneo, flutuação da ingestão de matéria seca (IMS) e incidências de rumenites e abscessos de fígado. O delineamento experimental foi inteiramente casualizado em arranjo fatorial 2 × 2, com seis repetições por tratamento, nos quais 48 bovinos machos inteiros de cada grupo genético (GG) avaliado [Brangus (BR) ou Nelore (NE)] foram alimentados com dietas contendo MON ou PAP fornecidos diariamente nas doses de 30 e 300 mg/kg de MS, respectivamente. Os animais passaram por três fases durante o estudo: adaptação (ADAP), crescimento, e terminação. As dietas fornecidas nestes períodos continham 55, 70 e 85% de concentrado, respectivamente. Não foi observado (P > 0,05) efeito principal dos aditivos alimentares (AA) sobre a maioria das características de desempenho, com exceção à IMS em quilos e em porcentagem do peso vivo, onde bovinos recebendo MON apresentaram (P < 0,05) menores IMS. Foi observado (P < 0,01) efeito principal dos AA e dos GG sobre as concentrações de bicarbonato, total de CO2 e excesso de base no fluído extra-celular, onde bovinos recebendo PAP, e aqueles da raça BR, apresentaram maiores concentrações desses metabólitos no sangue. Animais que receberam PAP e aqueles da raça BR, apresentaram maiores (P < 0,01) valores de pH na fase de ADAP que animais suplementados com MON (7,427 vs. 7,400) e animais NE, respectivamente. Bovinos BR apresentaram (P < 0,01) maior ganho de peso diário que bovinos NE em ambas as fases, contudo conversão alimentar similar (P > 0,05). Por outro lado, bovinos NE mostraram maior (P < 0,05) incidência de lesões ruminais. Assim sendo, a suplementação de PAP pode ser uma eventual alternativa... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study, conducted at the São Paulo State University feedlot, Botucatu Campus, Brazil, was designed to test monensin (MON) and a polyclonal antibody preparation (PAP) against rumen bacteria on feedlot performance of Brangus (BR) and Nellore (NE) cattle. The experiment was designed as a 2 × 2 factorial arrangement using repeated measures over time, replicated 6 times (4 bullocks/pen), in which 48 8-mo-old bullocks of each of two breeds (BD) evaluated were fed diets containing either MON at 30 mg•kg-1 or PAP at 300mg•kg-1 of dry matter (DM). Measures over time were taken according to the phase and level of concentrate fed during the study: 55, 70 and 85%. Phases were named adaptation (AD), growing (GR), and final (FN), respectively. No significant (P > 0.05) feed additives (FA) main effect was observed for any of the feedlot performance variables, with the exception (P < 0.05) of DM intake expressed in kg (PAP= 7.60; MON=7.24) and in % of body weight (PAP= 2.11; MON=2.03). Feeding MON led to greater (P < 0.05) subcutaneous fat deposition throughout the study, and decreased (P < 0.05) the final rib eye area (RBA). As a result a reduced (P < 0.05) RBA deposition, mainly in GR phase, it was observed when feeding MON was compared to feeding PAP. A significant (P < 0.01) FA and BD main effects were found for bicarbonate, total CO2, and base excess in extracellular fluid, where bullocks receiving PAP, and those BR cattle, presented greater concentrations of these metabolites in the blood. Likewise, BR cattle and bullocks receiving PAP had (P < 0.01) higher blood pH in the AD phase than NE cattle and bullocks fed MON (7.427 vs. 7.400), respectively. BR had greater (P < 0.01) average daily gain in GR and FN phases, but similar (P > 0.05) feed conversion was observed. On the other hand, NE bullocks presented greater (P < 0.05) incidence of rumenites. Thus, feeding PAP may... (Complete abstract click electronic access below) / Doutor
26

Efeitos da administração de melatonina sobre a resposta imune em ratos Wistar na amebíase hepática / Effects of melatonin administration on the immune response of Wistar rats in amebic liver abscess

Fernandez, Vania 04 October 2012 (has links)
Os trofozoítos de Entamoeba histolytica após se evadirem de uma complexa resposta imune ao nível da mucosa intestinal, invadem o epitélio, podendo disseminar-se pela circulação portal, atingindo o fígado e outros órgãos. A amebíase hepática é a forma mais comum de amebíase extraintestinal e corresponde a menos de 1% dos casos clínicos de amebíase. A modulação das respostas imunológicas frente à administração de substâncias farmacologicamente ativas em modelos experimentais infectados por diferentes patógenos tem contribuído de maneira importante nas investigações de terapias alternativas para colaborar no tratamento das diferentes doenças parasitárias. A melatonina (N-acetil-5- metoxitriptamina) é uma indolamina cuja síntese ocorre na glândula pineal e em vários locais extrapineais, como, as células do sistema imune, retina, medula óssea, pele, leucócitos, e trato gastrointestinal. É uma molécula pleiotrópica que possui atividades imunoestimulatórias e efeitos pró e anti-inflamatórios. O presente estudo teve como objetivo avaliar um possível efeito imunomodulatório subseqüente à administração oral de melatonina em ratos da linhagem Wistar machos infectados no fígado pela cepa HM1-IMSS de Entamoeba histolytica na fase aguda da amebíase hepática experimental. Foram utilizados vários parâmetros como: dosagens das citocinas IFN-?, IL-4, análise por citometria de fluxo das populações celulares TCD3+, TCD4+, TCD8+, CD45+, CD161+ e produção de óxido nítrico. Através dos resultados obtidos, podemos concluir que a melatonina exerceu seus efeitos imunomodulatórios, ora induzindo uma reposta imune mais eficaz de forma a minimizar os efeitos patogênicos da infecção ao mesmo tempo em que exerceu um papel anti-inflamatório na tentativa de manter a homeostase imunológica do hospedeiro, evitando uma exacerbação dessas respostas que certamente iriam influenciar o grau de patogenicidade desta parasitose. / The trophozoites of Entamoeba histolytica after evade a complex immune response at the intestinal mucosal level, invade the epithelial layer and may spread into the portal circulation reaching the liver and other organs. The amoebic liver abscess (ALA) is the most common form of the extraintestinal amebiasis and is less than 1% of clinical cases of human amoebiasis. The modulation of immune responses by the administration of pharmacological active substances in experimental models infected by different pathogens has contributed in investigations of alternative therapies in order to aid the treatment of various parasitic diseases. Melatonin (N-acetyl-5-methoxytryptamine) is an indolamine whose synthesis occurs in the pineal gland and in several extra-pineal locations such as the immune system cells, retina, bone marrow, skin, leukocytes, and gastrointestinal tract. This molecule has pleiotropic effects with immunoenhancing actions besides pro and anti inflammatory effects. The present study aimed to evaluate a possible immunomodulatory effect following the oral administration of melatonin in male Wistar rats infected with the strain HM1-IMSS of E. histolytica during the acute phase of experimental amebic liver abscess. Several immune parameters were evaluated such as of cytokines IFN-?, IL-4, flow cytometry analysis of cell populations TCD3+, TCD4+, TCD8+, CD45+, CD161+, and nitric oxide production. According to our results, we can conclude that melatonin exerted its immunomodulatory actions, once triggering a more accurate host´s immune response reducing the pathogenic effects from the infection and at the same time, exerting an anti-inflammatory role in the attempt to control host´s immune homeostasis, avoiding an exacerbation of these responses that would certainly influence the degree of pathogenicity of this parasitosis.
27

Estudo retrospectivo e prospectivo da presença de abscessos hepáticos em bovinos abatidos em um frigorífico paulista / Retrospective and prospective survey of liver abscesses in slaughtered Brazilian cattle

Vechiato, Thales dos Anjos de Faria 03 April 2009 (has links)
O presente estudo se baseou em levantamentos retrospectivos e prospectivos obtidos de bovinos abatidos no Frigorífico Bertin, em Lins-SP. No primeiro levantamento consultaram-se os registros do Serviço de Inspeção Federal de ocorrência de alterações hepáticas em 1.568.821 bovinos (85% machos e 15% fêmeas), proveniente de seis Estados (SP, MS, PR, GO, MT e MG) durante os anos de 2002 a 2006. Consideraram-se os animais abatidos no último trimestre de cada ano como terminados em confinamento, sendo os demais criados continuamente em regime extensivo. Os abscessos hepáticos (1,60%) foram a segunda mais freqüente alteração hepática após a teleangectasia (1,67%). A freqüência desses abscessos foi maior em bovinos confinados (2,54%) que nos criados extensivamente (1,28%) e em fêmeas (1,85%) que em machos (1,56%). O confinamento aumenta o fator de risco (FR) de surgimento de abscessos hepáticos na ordem de 2,01 vezes. Maior freqüência de abscessos foi registrada em bovinos oriundos do Paraná, em ambos os sistemas de terminação. No levantamento prospectivo foram acompanhados o abate de 1.617 bovinos nos meses de dezembro de 2007 (n=858) e outubro de 2008 (n=759). Os abscessos hepáticos foram registrados de acordo com a freqüência, tamanho, número e localização dos mesmos em 1.617 animais; a mucosa ruminal foi avaliada (n=1.397) quanto à presença de ruminite, sua classificação e área afetada; e os pulmões (n=759) examinados para a detecção de hepatização pulmonar nas diferentes regiões, lóbos e lóbulos pulmonares, assim como grau de acometimento nos lóbulos. Foram detectados abscessos hepáticos, ruminites e pulmões hepatizados em 3,29%, 11,88% e 8,30% dos animais, respectivamente. Os abscessos estiveram igualmente distribuídos em todas as quatro regiões hepáticas, e na maioria dos casos (78,26%) os mesmos eram de pequeno tamanho (< 2,5cm) e número (até dois/órgão). Foram encontrados quatro tipos de ruminites, sendo a mais freqüente a retração cicatricial (54,22%), seguido de retalhos aderentes (24,10%), vilosidades aderidas (13,25%) e ruminite erosiva (8,43%). Em 32,53% desses casos à área afetada do rúmen ultrapassava os 300cm2. Animais com ruminite apresentavam um altíssimo risco (FR=12,67x) de manifestar abscessos hepáticos e hepatização pulmonar (FR=5,8x), com destaque para a ruminite erosiva. A hepatização pulmonar foi mais freqüente na região ventral (71,4%) que dorsal (28,6%), nos lóbulos esquerdos (59,79%) que direitos (40,21%) e na maioria dos casos acometia apenas um lóbulo (53,97%) não atingindo a hepatização mais do que 50% deste (66,6%). Abscessos hepáticos ocorreram com maior freqüência quando concomitantemente um único lóbulo pulmonar era acometido (FR=3,0x) e este se apresentava com menos de 50% de seu parênquima hepatizado (FR=11,61x). / A retrospective and prospective survey was carried out in cattle slaughtered in a private abattoir in the State of Sao Paulo, Brazil. The first survey was based on the reports done by the Federal Inspection Service of the liver condemnations among 1,568,821 cattle (85% steers; 15% cows and heifers) from six different Brazilian states during 2002 and 2006. Feedlot cattle were mostly slaughtered in the last trimester of each year, while the cattle bred extensively were in the remaining months. The abscesses (1.60%) were the second highest cause of liver condemnation after telangiectasis (1.67%). The frequency of liver abscesses were higher in feedlot cattle (2.54%) than those bred extensively (1.28%), female (1.85%) than male (1.56%). Feedlot increased the outcome (odds ratio OD= 2.01x) of liver abscess. The highest frequency of liver abscess was detected in feedlot and extensively bred cattle from the Parana state. The prospective survey was carried out following the slaughtering of 1,617 cattle during the months of December 2007 (n=858) and October 2008 (n=759). The abscesses frequency, size, number and location in the liver were recorded in all animals; the rumen mucosa (n=1,397) was examined for the presence, type and size of ruminitis; the lungs (n=759) were also examined for detection of consolidation, evaluating the affected region, number of lobes and lesion score. The following frequencies were seen: liver abscess (3.29%), ruminitis (11.88%) and lung consolidation (8.30%). The abscesses were equally distributed in all hepatic regions; most abscesses (78.2%) were small (< 2.5cm) and present in low number (1-2/liver). Four different types of ruminitis were seen: scars (54.22%), adherent contents (21.10%), clumped villi (13.25%) and erosive ruminitis (8.43%). In many cases (32.53%) the ruminitis spread to an area larger than 300cm2. Cattle with ruminitis had a very high risk of contracting liver abscesses (OD=12.67x) and lung consolidation (OR= 5.8x), principally with erosive ruminitis. Lung consolidation was mostly seen in the ventral (71.4%) than dorsal areas (28.6%), in the left (59.79%) than right lobes (40.21%); in most cases a single lobe was affected (53.97%) and less than 50% of the lobe was consolidated (66.6%). Liver abscesses were commonly seen in cattle with a single lobe (OD=3.0x) and less than 50% of this lobe consolidated (OR=11.61x).
28

Perfil de resistência a agentes antimicrobianos de bactérias anaeróbias isoladas de infecções endodônticas agudas

Lang, Pauline Mastella January 2017 (has links)
A presente tese teve como objetivos analisar o padrão de resistência a antimicrobianos de bactérias isoladas de infecções endodônticas agudas por meio de uma revisão sistemática e meta-análise (capítulo 1); identificar e determinar a diversidade genotípica, a sensibilidade bacteriana e os fatores de virulência de anaeróbios facultativos isolados em casos de abscesso apical agudo (capítulo 2); e realizar, por meio de uma proposta de informativo, a difusão de informações geradas com orientações sobre o uso de agentes antibióticos em infecções endodônticas agudas para dentistas e pacientes (capítulo 3). A revisão sistemática foi realizada por meio de pesquisa em base de dados na internet e na literatura cinza até maio de 2015. As normas do PRISMA foram seguidas. Estudos clínicos em humanos que avaliaram o perfil de resistência a antimicrobianos de isolados de infecções endodônticas agudas primárias por meio de métodos laboratoriais foram incluídos. O efeito randômico da Meta-análise foi empregado, e o desfecho foi descrito reunindo as taxas de resistência para cada antibiótico testado. Os dados de sete estudos foram extraídos. A taxa de resistência para 15 diferentes agentes antibióticos foram avaliadas, variando entre 3,5% a 40%. Baixas taxas de resistência foram observadas para amoxicilina + clavulanato e amoxicilina, e altas taxas foram observadas para tetraciclina. No capítulo 2, amostras de canais radiculares foram coletadas de sete dentes com diagnóstico de abscesso apical agudo. Bactérias anaeróbias facultativas foram identificadas com o auxílio de métodos fenotípicos e MALDI-TOF MS. A sensibilidade antimicrobiana das cepas isoladas foi determinada para benzilpenicilina, eritromicina e clindamicina por meio da difusão em disco. Bactérias anaeróbias facultativas foram isoladas de 3 dentes. Streptococcus spp., Staphylococcus aureus, Enterococcus faecalis, e Actinomyces viscosus foram identificados. Streptococcus spp. e S. aureus foram sensíveis à benzilpenicilina. E. faecalis (24 cepas) isolados de um mesmo paciente tiveram a sensibilidade antimicrobiana determinada por meio da concentração inibitória mínima para benzilpenicilina, amoxicilina e amoxicilina + clavulanato utilizando-se o E-test. A diversidade genotípica e a presença de fatores de virulência (ace, asa, gelE, efaA, cylA, esp) nas cepas de E. faecalis foi analisada por meio do PFGE e PCR, respectivamente. A expressão da gelatinase e da hemolisina foi testada, e a produção de biofilme quantificada. E. faecalis foram sensíveis aos antibióticos beta-lactâmicos. O mesmo perfil cromossonal de DNA foi revelado para cepas de E. faecalis isoladas. Os genes gelE, ace e efaA foram detectados em 18 cepas. A expressão da gelatinase e a produção de biofilme foram observadas. Cepas de E. faecalis tiveram o mesmo perfil de DNA cromossomal, porém parecem apresentar diferentes perfis de virulência. No capítulo 3 foram apresentadas duas propostas de textos informativos. A primeira com o objetivo de orientar o dentista sobre o uso correto dos antibióticos sistêmicos em endodontia. A segunda visa informar os pacientes sobre a utilização dos antibióticos e esclarecer possíveis dúvidas. / The present thesis aimed to analyze the antimicrobial resistance profile of bacteria isolated from acute endodontic infections through a systematic review and meta-analysis (Chapter 1); to identify and determine the genotypic diversity, antimicrobial susceptibility and virulence factors of isolated facultative anaerobes in isolates from acute apical abscess (Chapter 2); and to provide information for dentist and patients generated from guidelines on the use of antibiotic agents in acute endodontic infections (Chapter 3). The electronic databases and the gray literature were searched up to May 2015 for systematic review. PRISMA guidelines were followed. The clinical studies in of humans that have evaluated the antimicrobial resistance of the isolates of primary acute endodontic infections through laboratorial methods were included. A random effect meta-analysis was employed, and the outcome was described as being the pooled resistance rates for each antimicrobial agent. The data from 7 studies were extracted. The resistance rates for 15 different antimicrobial agents were evaluated, ranging from 3.5% to 40.0%. Lower resistance rates were observed for amoxicillin+clavulanate and amoxicillin, and higher resistant rates were detected for tetracycline. In Chapter 2, root canal samples were collected from seven teeth. Facultative anaerobic bacteria were identified by phenotypic methods and MALDI-TOF MS. Antimicrobial susceptibility of strains was determined to benzylpenicillin, erythromycin and clindamycin by disk-diffusion. Facultative anaerobic bacteria were isolated from 3 teeth. Streptococcus spp., Staphylococcus aureus, Enterococcus faecalis, and Actinomyces viscosus were found. Streptococcus spp. and S. aureus were susceptible to benzylpenicillin. E. faecalis strains (n=24) isolated from the same patients had their susceptibility determined by minimum inhibitory concentration of benzylpenicillin, amoxicillin and amoxicillin + clavulanate using the E-test. The genotypic diversity and virulence factors (ace, asa, gelE, efaA, cylA, esp) were analyzed in E. faecalis strains by PFGE and PCR, respectively. Phenotypic expression of gelatinase and cytolysin were tested. Biofilm production was quantified. All the E. faecalis strains were susceptible to β-lactam antibiotics. The same chromosomal DNA fragmentation profile was revealed to E. faecalis strains isolated. The gelE, ace and efaA genes were detected in 18 E. faecalis strains. Gelatinase expression and biofilm production were observed. E. faecalis strains had the same chromosomal DNA profile, but showed virulence profiles different. In Chapter 3, two sugestion for information texts were presented. The first aims to guide dentists on the proper use of systemic antibiotics in endodontics. The second aims to inform patients about the use of antibiotics and clarify possible doubts.
29

The Classification of In Vivo Proton Magnetic Resonance Spectroscopy of Brain Abscesses Using Principal Component Analysis

Lu, Ssu-Ying 06 July 2011 (has links)
Proton magnetic resonance spectroscopy has been widely applied to the diagnosis of brain diseases. In the meanwhile, the classification of brain abscesses plays an important role on the accurate prognosis in clinics. Recently, the interest in using proton MRS to classify pyogenic brain abscesses has been arising because of its non-invasive property and good accuracy in detecting metabolites. The brain abscess can be classified by means of the metabolites observed in the MR spectra, which may thus benefit the accuracy of the brain abscess diagnosis clinically. However, the interpretation of MR spectra by experienced radiologists can be also very subjective and therefore results in the variation of diagnosis. In this study, we investigate the potential possibility of using Principal Component Analysis (PCA) to classify the short TE MR spectra in more objective way.
30

The Classification of In Vivo MR Spectra on Brain Abscesses Patients Using Independent Component Analysis

Liu, Cheng-Chih 04 September 2012 (has links)
Magnetic Resonance Imaging (MRI) can obtain the tissues of in vivo non-invasively. Proton MR Spectroscopy uses the resonance principle to collect the signals of proton and transforms them to spectrums. It provides information of metabolites in patient¡¦s brain for doctors to observe the change of pathology. Observing the metabolites of brain abscess patients is most important process in clinical diagnosis and treatment. Then, doctors use different spectrums of echo time (TE) to enhance the accuracy in the diagnosis. In our study, we use independent component analysis (ICA) to analyze MR spectroscopy. After analyzing, the independent components represent the elements which compose the input data. Then, we use the projection which is mentioned by Ssu-Ying Lu¡¦s Thesis to help us observe the relationship between independent components and spectrums of patients. We also discuss the result of spectrums with using ICA and PCA and discover some questions (whether it need to do scale normalization before inputting data or not, the result of scale normalization doesn¡¦t expect, and the peak in some independent components confuse us by locating in indistinct place) to discuss and to find possible reason after experiments.

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