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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.
41

Técnica de biopsia renal "de janela" modificada com exteriorização do rim em gatos. Estudo das complicações clínicas, alterações laboratoriais e qualidade das amostras obtidas /

Bissoli, Ednilse D'Amico Galego. January 2005 (has links)
Orientador: Flávio Quaresma Moutinho / Resumo: Objetivando avaliar a viabilidade da técnica de biopsia renal "de janela" modificada com exteriorização do rim em gatos, foram estudadas as complicações decorrentes do procedimento e a qualidade das amostras obtidas. Para tanto, foram utilizados 25 gatos, sem raça definida, adultos, machos e com peso corporal entre 2,5 e 5 kg, pertencendo a um único grupo. A biopsia renal, pela técnica "de janela" modificada foi realizada nos rins esquerdo e direito utilizando-se agulhas do tipo "Spring-Cut", semi-automatizadas de 18 gauge. Os animais foram avaliados antes e após a biopsia, em intervalos de 2, 24 e 168 horas. Os animais foram acompanhados por meio de exame clínico e testes laboratoriais durante este período. A qualidade das amostras de biopsia foi avaliada pela microscopia de luz, de acordo com o número de glomérulos existentes, sendo considerado como padrão para a classificação da amostra, a presença de no mínimo cinco glomérulos por biopsia. As principais alterações clínicas observadas após a biopsia renal foram presença de hematúria transitória e formação de hematomas perirrenais. Nenhum animal do experimento veio a óbito ou apresentou complicações maiores. Das amostras de biopsia avaliadas, 84% apresentaram cinco ou mais glomérulos. Desta forma, conclui-se que a técnica estudada associada ao tipo de agulha utilizada ("Spring-Cut" semi-automatizada) pode ser considerada segura e de grande valor diagnóstico. / Abstract: Aiming to evaluate the technical viability of modified "keyhole" renal biopsy with open up of the Kidney in cats, it was studied the involvement originated from the procedures and the quality of the acquired samples. For that, it was used 25 cats with no defined breed, adults, male and weighing between 2 and a half and 5 kilos, belonging in just on group. The renal biopsy, by modified "keyhole" technique was performed in the right and left kidney using "Spring Cut" needles, semiautomatic of 18 gauge. The animals were evaluated before and after the biopsy, in a period of 2, 24 and 168 hours.The animals wore to be present at by clinic examination and laboratory tests during this period. It was done the observation by light microscopy, according to existent glomeruli, it was considered as pattern for the sample classification, the presence of at least 5 glomeruli for the biopsy. The main observed clinical alterations after the renal biopsy was the presence of transitory haematuria and formation of subcapsular haematomas. No animal from the experience has died or shoed serious complications. From the evaluated biopsy samples, 84% showed five or more glomeruli. Then, it is inferred that the studied technique associated with the used needle ("Spring-Cut" semiautomatic) can be considered safe and great diagnostic value. / Mestre
42

Aspectos histopatológicos da polipose nasossinusal pré e pós corticoterapia tópica / Histopathological aspects of rhinosinusal polyps before and after topicl corticosteroid

Dias, Arethusa Ingrid de Liz Medeiros, 1982- 11 August 2013 (has links)
Orientadores: Carlos Takahiro Chone, Eulalia Sakano / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-23T21:36:35Z (GMT). No. of bitstreams: 1 Dias_ArethusaIngriddeLizMedeiros_M.pdf: 1854166 bytes, checksum: ba03fb9925b6895d98d898626cbb0986 (MD5) Previous issue date: 2013 / Resumo: Existem poucos estudos que correlacionam os aspectos histopatológicos dos pólipos nasossinusais após tratamento com corticosteróide nasal. O objetivo do presente estudo foi analisar as alterações histopatológicas dos pólipos nasais antes e após o uso de corticosteróide tópico nasal por três meses. Foi utilizado ensaio clínico, sem grupo controle. Biópsias de pólipos nasais de pacientes com polipose nasossinusal foram realizadas antes e após três meses de uso de budesonida 50 mcg, duas vezes ao dia, para análise histopatológica. Nos 35 pacientes incluídos, observou-se, após corticoterapia, um aumento da intensidade do edema na submucosa, sendo que 50% destes apresentavam edema intenso, uma redução de 47% de pacientes com infiltrado intenso de eosinófilos (p= 0,07) e não houve alteração quanto ao infiltrado de linfócitos, neutrófilos e plasmócitos. Com relação à presença dos cistos glandulares, houve aumento estatisticamente significante (p=0,031). Não se observou variação na espessura da membrana basal (p=0,344). Concluiu-se que o uso de corticosteróide tópico nasal por três meses mostrou variações no estroma e na intensidade das células dos pólipos nasossinusais / Abstract: There are few papers regarding the effect of corticosteroids on histopathology of sinonasal polyps. The aim of this study was to analyze the histopathology of nasal polyps before and after three months of nasal topical corticosteroids. It was used a non-controlled clinical trial. Nasal polyps biopsies of patients with sinonasal polyposis were performed before and after three months of budesonide 50 mcg BID for histopathological analysis. Among the 35 patients included, after steroid therapy, it was observed an increase in submucosal edema intensity, half of them presenting intense edema, a 47% reduction of cases with intense eosinophils infiltration (p = 0.07). Lymphocytes, neutrophils and plasma cells infiltration in polyps was not altered by treatment. It was observed statistically significant increase in presence of glandular cysts after treatment (p = 0.031). The thickness of the basement membrane did not changes (p=0.344). This study concluded that three months use of topical nasal corticosteroids resulted in stromal and cellular variations of sinonasal polyps / Mestrado / Otorrinolaringologia / Mestra em Ciências Médicas
43

Tumor biopsy and patient enrollment in clinical trials for advanced hepatocellular carcinoma

Rimassa, Lorenza, Reig, Maria, Abbadessa, Giovanni, Peck-Radosavljevic, Markus, Harris, William, Zagonel, Vittorina, Pastorelli, Davide, Rota Caremoli, Elena, Porta, Camillo, Damjanov, Nevena, Patel, Hitendra, Daniele, Bruno, Lamar, Maria, Schwartz, Brian, Goldberg, Terri, Santoro, Armando, Bruix, Jordi January 2017 (has links)
Tumor biopsies may help to reliably distinguish hepatocellular carcinoma (HCC) from other tumors, mostly cholangiocarcinoma as well as to identify the patient populations who most benefit from target-driven HCC treatments, in order to improve the success rate of experimental therapies. Clarifying tumor biology may also lead to identify biomarkers with prognostic role and/or enabling to predict response or resistance to therapies. Recently, clinical trials have more efficiently included biomarker endpoints and increasingly collected tumor tissue from enrolled patients. Due to their frail status and sometimes fast-progressing disease, the performance status of patients with HCC progressing on first-line therapy can deteriorate quickly, preventing their enrollment in clinical trials. However, the challenge of identifying the proper patient at the proper time can be overcome by periodic inter-department meetings involving the key specialists taking care of HCC patients, and solid networks between research centers and referring institutions. An early planned biopsy would also facilitate timely inclusion of patients in biology-driven clinical trials. Ultimately, institution of multidisciplinary teams can optimize treatment choice, biopsy timing, and quick enrollment of patients in clinical trials, before their performance status deteriorates.
44

Diagnosis and surgical treatment of suspicious nonpalpable breast lesions and early breast cancer

Saarela, A. (Arto) 02 September 1999 (has links)
Abstract The purposes of the present research were to evaluate (1) the value of ultrasonographically guided fine-needle aspiration biopsy (US-FNAB) in nonpalpable suspicious breast lesions, (2) the preoperative use of methylene blue staining in nonpalpable galactographically suspicious breast lesions, (3) the determinants of positive histologic margins and residual cancer in wire-guided biopsy (WGB) of nonpalpable breast cancer and in lumpectomy for early breast cancer and the determinants of positive radiologic margins and the correlation between radiologic and histologic margins and residual disease in WGB of nonpalpable breast cancer, (4) the assessment of lumpectomy margins by touch preparation cytology in early breast cancer, and (5) the cosmetic outcome of WGB performed for benign breast lesions. The sensitivity and specificity of US-FNAB in 90 nonpalpable breast lesions were 84% and 93%, respectively. Preoperative methylene blue staining was successful in 22 out of 30 (73%) cases, making subsequent selective minimal volume microdochectomy easy to perform. Multivariate analysis of 21 prospectively evaluated variables was done after 71 WGBs of nonpalpable breast cancer followed by 54 re-excisions. Large mammographic lesions had more often positive radiologic margins. Multifocality, large pathologic size and superficial excision were related to positive histologic margins and multifocality to residual disease in re-excisions. The sensitivity and specificity of specimen radiography for predicting histologic margins were 38% and 81% and those for residual disease 27% and 79%, respectively. The corresponding figures for histologic margins in predicting residual disease were 85% and 59%, respectively. In a prospective series of 55 consecutive lumpectomies for early breast cancer, positive histologic margins were found more often in the presence of intraductal cancer and if the pathologic size of the index tumor was large. Residual disease was found in 38% of the cases with positive and in 15% of the cases with negative histologic margins. A multifocal and nonpalpable index tumor predicted residual cancer in 34 re-excision specimens. The sensitivity and specificity of touch preparation cytology in predicting histologic margins were 38% and 85%, respectively. In WGB, the overall cosmesis 6 months after surgery was satisfactory in 75 % of the 101 prospectively evaluated patients with benign proven lesions. Cosmesis was poorer after deep excisions and complications. The results indicate that US-FNAB is a useful tool in evaluating nonpalpable suspicious breast lesions. Preoperative methylene blue staining crucially facilitates selective minimal volume microdochectomy in three-quarters of cases. To obtain free margins in WGB, mammographically and pathologically large lesions should be removed with wider excisions extending down to the fascia. However, radiologic margins in WGB and histologic margins both in WGB and in lumpectomy for early breast cancer may be misleading. Re-excision of the biopsy site of multifocal tumors after WGB and lumpectomy should be considered. This is also important after superficial excision in WGB due to the considerable risk of residual disease. Touch preparation cytology cannot be recommended for the assessment of margins in lumpectomy specimens of early breast cancer. Cosmetic outcome after WGB of benign breast lesions is satisfactory in 75 % of cases. Deep excisions and complications endanger the cosmetic outcome. Preoperative biopsy and tumor localization methods have proven their utility; nevertheless, free margins are still difficult to obtain and to evaluate accurately. The surgeon may often be forced to choose between free margins and an acceptable cosmetic outcome.
45

A core biopsy estereotáxica no diagnóstico das lesões mamárias impalpáveis altamente suspeitas de malignidade (categoria mamográfica BI-RADS® 5): um estudo de correlação radiologia/anatomia patológica

Ferreira Lima Júnior, Álvaro January 2007 (has links)
Made available in DSpace on 2014-06-12T23:04:14Z (GMT). No. of bitstreams: 2 arquivo8851_1.pdf: 4717828 bytes, checksum: 592acd5b2b91d1cead758a1666f091db (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2007 / As indicações clínicas da core biopsy obedece aos mesmos critérios utilizados para biópsia cirúrgica, mas não há consenso na literatura quanto a sua indicação para avaliação das lesões na categoria mamográfica BI-RADS® 5 (ACR/Breast Imaging Reporting and Data System). Objetivo: Determinar a associação entre as alterações mamográficas e o diagnóstico histopatológico de material obtido por core biopsy estereotáxica de lesões mamárias impalpáveis classificadas na categoria mamográfica BI-RADS® 5, estabelecendo o valor preditivo positivo da mamografia nas lesões altamente suspeitas de malignidade. Materiais e métodos: Por meio de estudo retrospectivo, transversal, analítico, de comparação entre métodos diagnósticos, foram analisadas 70 core biopsies de lesões mamárias impalpáveis, classificadas radiologicamente como altamente suspeitas de malignidade (BI-RADS® 5), de 70 pacientes, atendidas em serviços privados de Anatomia Patológica e Radiologia da cidade do Recife, Pernambuco, no período de 2001 a 2006. Resultados: Eram do sexo feminino 68 (97,1%) pacientes e 2 (2,9%), do masculino. A idade variou de 17 a 87 anos, com média de 58 ± 15 anos. A mama esquerda foi acometida em 42 (60%) casos e a direita, em 28 (40%). Predominaram localização das lesões no QSE (44 casos; 62,9%) e nódulos irregulares espiculados (49 casos; 70%), 11 (15,7%) dos quais associados a microcalcificações. As microcalcificações estavam presentes em 31(44,3%) casos; sendo 16 (22,9%) casos não associados a nódulos, distorção arquitetural ou densidade assimétrica. As core biopsies foram constituídas por 3 a 16 fragmentos (média: 6±2). Não houve diferença na distribuição de freqüência de número de fragmentos em função dos diagnósticos histopatológicos (p>0,05) ou radiológicos (p=0,63). Houve diagnóstico de: 59 (84,3%) casos de carcinoma, 7 (10%) casos de lesões benignas e 4 (5,7%) com lesão borderline. O carcinoma invasivo foi o mais freqüente (49 casos; 70%) e em 15 (21,4%) casos associou-se a componente in situ. O carcinoma in situ puro correspondeu a 10 (14,3%) casos. Houve associação significante entre nódulos irregulares espiculados e carcinoma invasivo (41 casos; 58,6%; p=0,005). O tipo histológico mais encontrado foi o carcinoma ductal invasivo (34 casos; 69,4%). Dentre os carcinomas invasivos, 36 (73,5%) casos tiveram grau histológico 2, com predomínio da soma dos escores igual a 6 (34 casos; 69,4%). O CDIS padrão comedônico puro associou-se mais freqüentemente às microcalcificações. O valor preditivo positivo da avaliação mamográfica na categoria BI-RADS® 5 foi de 84,3%. O maior valor preditivo positivo foi verificado em nódulo irregular espiculado com microcalcificações, com ou sem, sem microcalcificações e microcalcificações sem nódulo (100%, 87,8%, 84,2% e 75%, respectivamente). Conclusões: A avaliação mamográfica das lesões impalpáveis enquadradas como altamente suspeitas de malignidade foi de alto valor preditivo para o diagnóstico de câncer, a maioria correspondendo a carcinoma invasivo. Os nódulos irregulares espiculados tiveram um alto valor preditivo para o diagnóstico de carcinoma, particularmente, quando associados às microcalcificações
46

Applications of aspiration lung biopsy with special reference to the pathogenesis of the resolution of acute and chronic lobar pneumonia

Woolf, Colin Rael 15 April 2020 (has links)
Lung biopsy is neither widely known nor practiced and it was only in 1949 that i first came across a paper on this subject. The title was: "Cellular analysis of the aspiration lung biopsy from normal and some pathological conditions by Z. Godlowski" (1949). The very term "lung biopsy" conjures up the picture of a needle being introduced into an air filled, very vascular structure where the bleeding of an injured vessel cannot readily be stopped, where the stage is set for air embolisms and where tension pneumothorax may occur. it was with great surprise but also an apparently innocuous procedure. Unfortunately, at that time, there was no opportunity to use the method. In 1950 I became the University Assistant at the New Somerset Hospital in Cape Town. Many of the cases admitted to the wards presented with chest pathology. Patients with pneumococcal lobar pneumonia were not infrequent and occasional cases did not resolve as expected but went on to become so-called chronic pneumonia. What happened when an acute lobar pneumonia went on to the chronic stage and why did this occur? it was suggested that investigae this problem.
47

Clinico-pathological features of repeat renal biopsies in patients with lupus nephritis at Groote Schuur Hospital, Cape Town

Kajawo, Shepherd January 2017 (has links)
Background: Repeat renal biopsies in patients with lupus nephritis (LN) are usually done to guide treatment or to establish disease chronicity. Their value is not clear from available literature. There is also no available data in Africa to guide clinicians. Methods: This was a retrospective study of patients undergoing a repeat renal biopsy between January 2003 and December 2014 from a single centre in Cape Town, South Africa. Relevant demographic, clinical and histological records of patients with repeat renal biopsies were documented. Comparison of data from 1st and 2nd renal biopsy was performed. Results: 44 patients had at least 2 biopsies done during the study period. Most patients were females (81.8%). The mean biopsy interval was 2.8± 1.8 (range 0.38 – 9.4) years. Proteinuria was the main indication for the repeat biopsy (36.1%). The glomerular filtration rate and proteinuria worsened between the two biopsies (p=0.001 and 0.019) respectively suggesting disease progression. Most patients (65.4%) with a non-proliferative class of LN at first biopsy progressed into a proliferative class whereas patients with initial proliferative LN at first biopsy (77.8%) remained as proliferative at repeat biopsy. Treatment was changed in 85% of patients at second biopsy. Conclusion: Repeat renal biopsies in patients with LN presents a useful means of assessing disease progression and provides guidance regarding modification of treatment. More studies are however required to evaluate the value of repeat biopsies and perhaps the need for protocol renal biopsies in patients with LN.
48

Needle Guide Efficacy and Safety in Pediatric Renal Biopsies

Taylor, Veronica 04 November 2019 (has links)
No description available.
49

Adult glioma managment with selective biopsy, voxel-wise radiomics, and simultaneous PET/MR imaging

Emily Diller (9167027) 30 July 2020 (has links)
Every year more than fourteen-thousand adults in the United States are diagnosed with glioma, the most common malignant tumor of the central nervous system. Gliomas arise from glue like glial cells and present with a range of grade and prognosis. Glioblastoma multiforme (GBM), a grade IV glioma, is the most common glioma subtype and carries dismal prognosis with fewer than one half of patients surviving one year after diagnosis. The standard treatment for GBM is resection followed by a cocktail of chemo and radiation therapy. Unfortunately, complete surgical resection is impossible for GBM, and intra-tumor heterogeneity, a GBM hallmark, negatively impacts chemo and radiation therapy efficacy. This thesis contains six chapters that evaluate advanced imaging and statistical methods that may be used to improve glioma management. Chapter one presents background information to establish the relationship of four subsequent studies with ranging topics on advanced imaging techniques, biopsy sampling, and radiomic analysis. In chapter two, a case report is presented that demonstrates the importance of advanced magnetic resonance imaging (MRI) such as arterial spin labeled (ASL) perfusion sequences. In this case, a patient with a benign cerebral lesion presents with receptive aphasia and of the imaging data acquired, only ASL showed decrease cerebral aphasia. Chapter three describes the impact biopsy selection has on correlation between prognostic and histologic features in 35 patients with GBM. Multiple biopsy selection methods were compared, resulting in a wide range in correlation significance. Chapter four presents different voxel-wise radiomic models in adult glioma patients. From one voxel-wise radiomic model, predicted disease compositions (PDC) were computed in 17 glioma patients and were able to significantly (α = 0.05) predict overall survival, tumor grade, and endothelial proliferation. Chapter five describes the feasibility and hardware constraints of simultaneous PET/MR imaging protocols. A dynamic infusion of fluorodeoxyglucose (FDG) was administered with simultaneous MR imaging including echo planar imaging (EPI) based sequences used for functional MRI (fMRI). Heat from the EPI sequences deposited in the PET detector hardware and resulted in significant hardware failure. Finally, chapter six provides outlook and application to glioma clinical management considering the methods and findings presented in each study.<br>
50

Developing SCAPE Microscopy for real-time, volumetric imaging at the point-of-care

Patel, Kripa Bharat January 2021 (has links)
Physicians are blind to the microscopic tissue structure that defines tissue type and pathologies during procedures. For diagnosis, tissue must be excised, fixed, and processed for histology, which can take anywhere from 20 minutes to days. This need for tissue excision and processing for microscopic visualization delays decision-making and necessitates repeat procedures. Limited sampling can also never fully eliminate the presence of disease. However, advances in optical sectioning techniques such as confocal and two-photon microscopy, which provide isotropic cellular-level resolution in bulk tissues, have obviated the need to physically section and process tissues for histology. Many optical imaging probes have been developed over the last three decades with the goal of demarcating tissue health in situ, either completely eliminating the need for tissue excision and processing for histopathology or guiding biopsy selection to reduce sampling bias. However, these techniques have faced major barriers to routine and widespread clinical use, including small 2D fields of view, limited contrast, slow imaging speeds and bulky laser sources. To address this critical need, SCAPE Microscopy, a light sheet-based microscopy technique recently developed in the Hillman lab, was developed for label-free, real-time, volumetric imaging at the point-of-care. SCAPE allows visualization of both cross-sectional and multilayer en face geometries in parallel and real-time, providing a more comprehensive view of tissue architecture than individual histology slides. Furthermore, tissues can be imaged label-free with structure shown through intrinsic fluorescence or in conjunction with intravenous or topical dyes. SCAPE’s video-rate speeds permit 3D stitching of large tissue areas and can withstand in vivo motion, which typically renders point-scanning techniques impractical. Most importantly, SCAPE is shown to allow 3D visualization of key histoarchitectural markers in human kidney biopsies through both endogenous and exogenous fluorophores. In this thesis work, a benchtop system is used for proof-of-concept imaging; however, miniaturized prototypes more suitable for clinical use are also presented. Further, high-throughput imaging of tissues is a critical but underserved need for bedside biopsy evaluation, as well as large-scale interrogation of structural organization and connectivity in the brain, retina and even whole model organisms. SCAPE provides near giga-voxel per second imaging rates that are well-suited for imaging large-scale ex vivo tissues at isotropic resolution at orders of magnitude faster speeds than point-scanning techniques. To this end, SCAPE was also developed as a versatile imaging platform for structural imaging of large-scale fresh, fixed, cleared and expanded samples for both bedside clinical evaluation and basic science research. It is demonstrated that planar samples of a few millimeters can be fully imaged at cellular resolution in just minutes by combining 3-axis stage-scanning and 3D stitching.

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