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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.
51

A New Device for Stereotactic ct-Guided Biopsy of the Canine Brain: Design, Construction, and Needle Placement Accuracy

Giroux, Alain G. 19 June 2000 (has links)
Computed tomography (CT) is an imaging technique that uses x-ray and computers to create cross-sectional images of structures. Stereotactic CT-guided biopsy is defined as the use of a stable apparatus to direct and perform tissue biopsies under CT guidance. For the brain, the principal advantage of stereotactic CT guidance over other biopsy techniques is its high accuracy in getting a sample from deep-seated lesions. The objectives of this study were to create an inexpensive CT-guided stereotactic device adaptable to different canine head sizes and to test the accuracy of the device for needle placement in deep-seated brain targets. A biopsy device was created that consists of four main components: a CT table fixation device, a head fixture, a needle fixture , and motion control system. Accuracy was tested using 16 head and neck specimens obtained from dogs euthanitized for reasons unrelated to the brain. Deep-seated (caudate nucleus and pituitary gland) targets were identified on CT. After a 5 mm craniotomy, the biopsy needle, with CT monitoring, was progressively introduced into the target. The final needle track distance was measured on CT. The brain was removed and sliced to verify placement of the needle tip within the target and to measure the actual needle track distance. The total cost of materials and construction for the stereotactic CT-guided biopsy device was $785.00. No difference in needle placement accuracy was identified for caudate and pituitary targets. Based on assessments by 2 independent observers, the caudate target was successfully hit 75% of the time. Pituitary targets were successfully hit 96.8 % of the time. Actual needle track lengths were an average of 3.2 mm less that the track length measured on CT. This difference was most likely due to incomplete staining of the bevel part of the needle track on gross specimens. / Master of Science
52

Survival and Cell Acquisition Rates After Preimplantation Embryo Biopsy: Use of Two Mechanical Techniques and Two Mouse Strains

Roudebush, William E., Kim, Jong G., Minhas, Brijinder S., Dodson, Melvin G. 01 January 1990 (has links)
Two strains of mouse embryos at the four- and eight-cell stages had biopsy specimens obtained by means of two different mechanical techniques: aspiration and displacement. Embryos and biopsy specimen cells were evaluated for survival and development. Blastomere acquisition rates were significantly higher with the displacement biopsy technique; however, no difference in survival or developmental rates was found in blastomere biopsy specimens removed from either four-cell or eight-cell embryos. A maximum of one blastomere can be removed from a four-cell embryo, whereas three blastomeres can be taken at biopsy from an eight-cell mouse embryo without significantly affecting embryo development, although mouse strain differences were noted. Intact, viable, biopsied blastomeres will develop in vitro when cocultured with morphologically intact embryos. Births of live offspring after embryo biopsy are reported.
53

A Diffuse Reflectance Spectroscopy Instrument for use in the Optical Biopsy of Brain Tumour Margins

Cappon, Derek J January 2016 (has links)
Optical biopsy is a medical technique that uses light to perform non-invasive analysis of tissue in-situ. This technology has many applications in the medical profession, opening up exciting new possibilities for surgical guidance and diagnosis of malignancies and other conditions. Optical biopsy allows a medical professional to perform near instantaneous, real time analysis of tissue composition without the need to physically remove tissue from the body, as required in traditional biopsy. A technique frequently used for this purpose is diffuse reflectance spectroscopy (DRS): collection and analysis of the spectrum of light reflected from a material. Another technique frequently used for optical biopsy is laser induced fluorescence spectroscopy (LIFS): analysis of the fluorescence spectrum returned by a material when illuminated at a specific wavelength. This thesis discusses the design and construction of a spatially resolved DRS system intended for use in a dual modality DRS and time resolved LIFS optical biopsy instrument for clinical analysis of brain tissue. This instrument is specifically intended for use in the surgical removal of malignant gliomas: infiltrating tumours associated with a poor patient prognosis. Theoretical simulation based studies were used to optimize the design of a compact, dual modality fibre optic probe for use in the system and a novel algorithm was developed to allow recovery of the optical properties of tissue from reflectance spectra obtained with this probe. This probe was manufactured and a corresponding spectrometer based system was created for the acquisition of diffuse reflectance spectra. Components were designed to allow sterilization and thus clinical use in an operating room environment. A laboratory trial of this system demonstrated its range and ability to recover the optical properties of lipid emulsion optical phantoms. / Thesis / Doctor of Philosophy (PhD)
54

Label-Free Microfluidic Devices for Single-Cell Analysis and Liquid Biopsies

Ghassemi, Parham 05 January 2023 (has links)
Mortality due to cancer is a global health issue that can be improved through further development of diagnostic and prognostic tools. Recent advancements in technologies aiding cancer research have made significant strides, however a demand for a non-invasive clinically relevant point-of-care tools exists. To accomplish this feat, the desired instrument needs to be low-cost, easy-to-operate, efficient, and have rapid processing and analysis. Microfluidic platforms in cancer research have proven to be advantageous due to its operation at the microscale, which has low costs, favorable physics, high precision, short experimentation time, and requires minimal reagent and sample sizes. Label-free technologies rely on cell biophysical characteristics to identify, evaluate, and study biological samples. Biomechanical probing of cells through deformability assays provides a label-free method of identifying cell health and monitoring response to physical and chemical stimuli. Bioimpedance analysis is an alternative versatile label-free method of evaluating cell characteristics by measuring cell response to electrical signals. Microfluidic technologies can facilitate biomechanical and bioelectrical analysis through deformability assays and impedance spectroscopy. This dissertation demonstrates scientific contributions towards single-cell analysis and liquid biopsy devices focusing on cancer research. First, cell deformability assays were improved through the introduction of multi-constriction channels, which revealed that cells have a non-linear response to deformation. Combining impedance analysis with microfluidic deformability assays provided a large dataset of mechano-electrical information, which improved cell characterization and greatly decreased post-processing times. Next, two unique biosensors demonstrated improved throughput while maintaining sensitivity of single-cell analysis assays through parallelization and incorporating machine learning for data processing. Liquid biopsies involve studying cancer cells in patient vascular systems, called circulating tumor cells (CTCs), through blood samples. CTC tests reveal valuable information on patient prognosis, diagnosis and can aide therapy selection in a minimally invasive manner. This body of work presents two liquid biopsy devices that enrich murine and human blood samples and isolate CTCs to ease detection and analysis. Additionally, a microfluidic CTC detection biosensor is introduced to reliably count and identify cancer cells in murine blood, where an extremely low-cost version of the assay is also validated. Thus, the assays presented in this dissertation show promise of microfluidic technologies towards point-of-care systems for cancer research. / Doctor of Philosophy / Cancer is the second leading cause of death worldwide with approximately 2 million new cases each year in the just United States. Significant research development for diagnostic and prognostic tools have been conducted, however they can be expensive, invasive, time-consuming, unreliable, and not always easily accessible. Thus, a tool that is cheap, minimally invasive, easy-to-use, and robust needs to be developed to combat these issues. Typical cancer studies have primarily focused on biological and biochemical methods for evaluation; however, researchers have begun to leverage small-scale biosensors that utilize biophysical attributes. Recent studies have proven that these lab-on-a-chip technologies can produce meaningful results by exploiting these biophysical characteristics. Microfluidics is a science that consists of sub-millimeter sized channels which show a great deal of promise as they require minimal materials and can quickly and efficiently analyze biological samples. Label-free methods of studying cells rely on their physical properties, such as size, deformability, density, and electrical properties. These biophysical characteristics can be easily obtained at the single-cell level through microfluidic-based assays. Measuring and monitoring these attributes can provide valuable information to help understand cancer cell response to stimuli such as chemotherapeutic drugs or other therapies. A liquid biopsy is a non-invasive method of evaluating cancer patients by studying circulating tumor cells (CTCs) that exist in their blood. This dissertation reports a wide range of label-free microfluidic assays that evaluate and study biological samples at the single-cell level and for liquid biopsies. These assays consist of microfluidic channels with sensors that can rapidly obtain biophysical characteristics and process blood samples for liquid biopsy applications. Uniquely modifying microfluidic channel geometries and sensor configurations improved upon previously developed single-cell and CTC-based tools. The resulting devices were low in cost, easy-to-use, efficient, and reliable methods that alleviates current issues in cancer research while showing clinical utility.
55

Ultrasound-assisted transthoracic diagnostic techniques

Koegelenberg, Coenraad Frederik Nicolaas 12 1900 (has links)
Thesis (PhD)--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: Although transthoracic ultrasonography is a well established modality, it is still underutilised by chest physicians. The aim of this research project was to investigate the feasibility, diagnostic yield and safety of ultrasound(US)-assisted transthoracic biopsies performed by clinicians in various settings relevant to daily practice of respiratory medicine. We conducted four clinical trials which are summarised below: 1. In a prospective study on the feasibility of US-assisted transthoracic fine needle aspiration (TTFNA) of drowned lung secondary to a proximal mass lesion, a novel indication for US-assisted TTFNA was described. TTFNA passes >20mm from the visceral pleura had a sensitivity of 74.2% and were also more likely to contain malignant cells than more superficial passes. The surprisingly high yield and the fact that no serious complications were observed validated this approach, which may be an alternative to bronchoscopy. 2. In the largest single-centre study on US-assisted TTFNA with rapid on-site evaluation (ROSE) and cutting needle biopsy (CNB) in the setting of superior vena cava (SVC) syndrome ever reported, we were able to accurately diagnose 96% of all patients who presented with an associated mass lesion that abutted or infiltrated the chest wall. No pneumothoraces or major haemorrhage was caused. We also validated the single-session approach, and were able to conclude that US-assisted TTFNA (with ROSE) is the initial investigation of choice in suspected bronchogenic carcinoma, whereas both TTFNA and CNB need to be performed in all other cases. 3. We continued to validate the novel single-session sequential approach in a study on anterosuperior mediastinal masses. US-assisted TTFNA with ROSE was performed on 45 consecutive patients, immediately followed by CNB where a provisional diagnosis of epithelial carcinoma or probable tuberculosis (TB) could not be established. An accurate cytological diagnosis was made in 73.3%, and was more likely to be diagnostic in epithelial carcinoma and TB than all other pathology (p<0.001). CNB yielded a diagnosis in 88.2%. Overall 93.3% of patients were diagnosed by the single-session approach. No pneumothorax or major haemorrhage was observed. 4. In a prospective study, we compared US-assisted Abrams and Tru-Cut needle biopsies with regard to their yield for pleural TB. Pleural biopsy specimens obtained with Abrams needles contained pleural tissue in 91.0% of cases and were diagnostic in 81.8%, whereas Tru-Cut needle biopsy specimens only contained pleural tissue in 78.7% (p=0.015) and were diagnostic in 65.2% (p=0.022). In conclusion, we investigated the feasibility of US-assisted biopsies performed by respiratory physicians in various settings, and consistently found acceptable to very high diagnostic yields with minimal complications. Furthermore, we were able to validate a novel indication for US-assisted TTFNA (US-assisted TTFNA of drowned lung), validate the use of a single-session sequential approach (USassisted TTFNA with ROSE followed by CNB where indicated) in at least two clinical settings (SVC syndrome and anterosuperior mediastinal masses) and we were able to show that US-assisted Abrams needle biopsy is superior to Tru-Cut needles biopsy when histological confirmation of TB pleuritis is required. / AFRIKAANSE OPSOMMING: Alhoewel transtorakale ultrasonografie ‘n gevestigde modaliteit is, word dit onderbenut deur pulmonoloë. Die doel van hierdie navorsingsprojek was om die praktiese uitvoerbaarheid, diagnostiese opbrengs en veiligheid van sonargerigte transtorakale biopsies uitgevoer deur klinici in verskeie situasies relevant tot die alledaagse praktyk te ontleed. Ons het vier kliniese proewe uitgevoer wat hieronder opgesom word: 1. In ‘n prospektiewe studie oor die praktiese uitvoerbaarheid van sonargerigte transtorakale fyn naald aspirasie (TTFNA) van areas van obstruktiewe pneumonitis sekondêr tot proksimale massa letsels, is ‘n nuwe indikasie vir sonargerigte TTFNA beskryf. TTFNA aspirasies wat >20mm van die visserale pleura geneem is, het ‘n sensitiwiteit van 74.2% gehad en was meer geneig om maligne selle op te lewer as meer oppervlakkige aspirasies. Die verbasende hoë diagnostiese sensitiwiteit en afwesigheid van ernstige komplikasies het die praktiese waarde van hierdie benadering bevestig. 2. In die grootste studie nog oor sonargerigte TTFNA met spoedige in-teater evalusies (SITE) en sny-naald biopsie (SNB) in die teenwoordigheid van superior vena cava (SVC) sindroom, kon ons 96% van pasiënte wat presenteer het met ‘n geassosieerde massa letsel wat die borskaswand betrek, akkuraat diagnoseer. Geen pneumotoraks of major bloeding is waargeneem nie. Ons kon ook die praktiese uitvoerbaarheid van ‘n enkelsessie benadering bevestig en kon tot die gevolgtrekking kom dat sonargerigte TTFNA (met SITE) die aanvanklike ondersoek van keuse is waar bronguskarsinoom vermoed word, maar dat beide TTFNA en SNB noodsaaklik is in ander gevalle. 3. Ons het voortgegaan om die waarde van die nuwe enkel-sessie benadering te bevestig in ‘n studie oor antero-superior mediastinale massas. Sonargerigte TTFNA met SITE is uitgevoer op 45 pasiënte en in gevalle waar ‘n voorlopige diagnose van epiteliale karsinoom of waarskynlike tuberkulose (TB) nie bevestig kon word nie, is dit onmiddelik gevolg deur SNB. ‘n Akkurate sitologiese diagnose is gemaak in 73.3% van gevalle en meer algemeen in epiteliale karsinoom en TB as ander patologie (p<001). SNB was diagnosties in 88.2%. In 93.3% kon ‘n diagnose verkry word met die enkel-sessie benadering. Geen pneumotoraks of major bloeding is waargeneem nie. 4. In ‘n prospektiewe studie is sonargerigte Abrams naald en Tru-Cut naald biopsies se opbrengs vir pleurale TB met mekaar vergelyk. Pleurale biopsie monsters wat met ‘n Abrams naalde geneem is, het pleurale weefsel in 91.0% gevalle getoon en was diagnosties in 81.8%, vergeleke met Tru-Cut naalde wat slegs in 87.7% pleurale weefsel opgelewer het (p=0.015) en wat net in in 65.2% diagnosties was (p=0.022). Opsommend het ons die praktiese uitvoerbaarheid van sonargerigte biopsies uitgevoer deur pulmonoloë in veskeie kliniese situasies nagevors, en het deurlopend aanvaarbare tot hoë diagnostiese opbrengste gevind met minimale komplikasies. Verder kon ons ‘n nuwe indikasie vir sonargerigte TTFNA beskryf en evalueer (sonargerigte TTFNA van obstruktiewe pneumonitis); ‘n enkel-sessie sekwensiële benadering se waarde bevestig (sonargerigte TTFNA met SITE, gevolg deur SNB waar aangedui) in ten minste twee kliniese situasies (SVC sindroom en anterosuperior mediastinale massas); en was dit moontlik om te bewys dat UK-geleide Abrams naald biopsies superior tot Tru-cut naald biopsies is in die histologiese bevestiging van TB pleuritis.
56

Clinical and quality aspects of native and transplant kidney biopsies in Sweden

Peters, Björn January 2016 (has links)
Percutaneous kidney biopsies have been performed since 1944 to establish diagnoses and treatment. Risk factors based on a limited amount of data have shown age, blood pressure, kidney function and needle size as some risk factors for biopsy complications. Although the techniques of biopsy have improved over the years, it is still an invasive procedure and serious complications can occur. The overall aim of this thesis was to obtain a large series of data from biopsy procedures and to use these to bring further light on risk factors to help minimize the risk for patients and to optimize diagnostics. Specific aims were to clarify if different factors, such as gender, diagnoses, localization of biopsies, needle types and sizes, could be useful to help minimize complication risks in native kidney biopsies (Nkb) and transplant kidney biopsies (Txb). Another point to investigate was the value of the Resistive Index (RI) obtained at ultrasound before performing Txb. Materials and methods: A protocol for prospective multicentre registration of various factors and complications associated with Nkb and Txb was designed. Consecutive data were obtained from seven hospitals. All biopsies, except one computer tomography-guided Nkb, were performed using real-time ultrasound guidance and an automated spring-loaded biopsy device. For the biopsies 14- to 20- Gauge (G) needles were used. The kidney function level, i.e. estimated glomerular filtration rate (eGFR), was calculated using the Modification of Diet in Renal Disease (MDRD) formula (GFR in mL/min per 1.73m2). For statistical analyses the IBM SPSS Statistic 22 (Armonk, NY, USA) and OpenEpi (Open Source Epidemiologic Statistics for Public Health, www.OpenEpi.com) were used. Data were presented as Odds Ratio (OR), Risk Ratio (RR) and Confidence Intervals (CI). A two sided p-value of &lt;0.05 was considered significant. In total 1299 consecutive biopsies (1039 native and 260 transplant kidneys) in 1178 patients (456 women and 722 men) were used for investigation. The median age of patients was 55 years (range 16 to 90 years). Major (require an intervention) and minor biopsy complications (no need of intervention) were registered. Results: The overall frequency of biopsy complications for Nkb was 8.8% (major 6.7%, minor 2.1%) and for Txb was 6.5% (major 3.8%, minor 2.7%); no death. Women had a higher risk for development of major (10.7% versus 4.7%, OR 2.4, CI 1.4-4.2) and overall biopsy complications (13.2% versus 6.5%, OR 2.2, CI 1.4-3.5) compared to men in Nkb. In Nkb, major complications were more common after biopsies from the right kidney in women versus men (10.8% vs 3.1%, OR 3.7, CI 1.5–9.5), in patients with lower versus higher BMI (25.5 vs 27.3, p=0.016) and for younger versus older age (44.8 vs 52.3 years, p=0.002). Lower (90 mmHg) compared to higher (98 mmHg) mean arterial pressure in Txb indicated a risk of major complications (p=0.039). Factors such as number of passes and kidney function did not influence complication rates. Biopsy needles of 16 G compared to 18 G showed more glomeruli per pass in Nkb (11 vs 8, p&lt;0.001) and in Txb (12 vs 8, p&lt;0.001). Sub-analysis revealed that 18 G 19 mm side-notch needles in Nkb resulted in more major (11.3% vs 3%, OR 4.1, CI 1.4-12.3) and overall complications (12.4% vs 4.8%, OR 2.8, CI 1.1-7.1) in women than in men. If the physician had performed less compared to more than four Nkb per year, minor (3.5% vs 1.4%, OR 2.6, CI 1.1-6.2) and overall complications (11.5% vs 7.4%, OR 1.6, CI 1.1-2.5) were more common. The localization of biopsy within the kidney (Nkb and Txb) was not a risk factor for complications. Patients with IgA-nephritis compared to patients with other diseases had a higher risk of major complications (11.7% vs 6.4 %, OR 1.8, CI 1.1–3.2). More major complications were found in Nkb if they had higher versus lower degree of glomerulosclerosis (31% vs 20 %, p=0.008) and in Txb if there was a higher versus lower degree of interstitial fibrosis (82% vs 33%, p&lt;0.001). Re-biopsies (Nkb) were more common in patients with IgA-nephritis than those with other diseases (4.7% vs 1.3 %, OR 4, CI 1.5–11), in younger versus older age (42.6 vs 52.3 years, p=0.031), and in those with a higher versus lower degree of interstitial fibrosis (63% vs 34 %, p=0.046). In Txb, a RI≥0.8 compared to RI&lt;0.8 predicted major (13.3% vs 3.2%, RR 4.2, CI 1.3-14.1) and overall biopsy complications (16.7% vs 5.3%, RR 3.2, CI 1.2-8.6). In the group &lt;0.8, RI correlated with age (rs=0.28, p&lt;0.001) and systolic blood pressure (rs=0.18, p=0.02). In the group ≥0.8, RI correlated with degree of interstitial fibrosis (rs=0.65, p=0.006) and systolic blood pressure (rs=0.40, p=0.03). The multiple regression analysis showed that the &lt;0.8 RI group correlated only with age (p&lt;0.001), whereas the ≥0.8 RI group correlated only with the degree of interstitial fibrosis (p=0.003). Conclusions: The present results motivate greater attention to be paid to the possibility of major side-effects after Nkb in women and biopsies from their right side, but as well in younger patients, and in those with lower BMI. This also applies for patients with presumptive IgA-nephritis and higher degree of glomerulosclerosis. In Txb, patients with higher degree of interstitial fibrosis had a greater risk of major complications. Moreover, the present data indicate that Nkb and Txb should be preferably taken with 16 G needles with 20 mm sample size. This results in better histological quality and there is a lower risk for major complications as compared to 18 G needles. The localization of biopsy within the kidney (Nkb and Txb) does not alter complication rates. For Nkb there were fewer complications if the physician had performed at least four biopsies per year. A RI≥0.8 in Txb indicates a greater risk for major and overall complications.
57

Advances in needle-related percutaneous intervention of focal liver lesions. / CUHK electronic theses & dissertations collection

January 2006 (has links)
Focal liver lesions are commonly encountered in clinical practice. To be able to differentiate potentially life-threatening lesions from clinically insignificant lesions, and to be able to treat them effectively are the two basic problems of a clinician who comes across such lesions. Percutaneous intervention of the liver with a needle enables a clinician to solve the above two problems in a minimally invasive manner. To date, there is a diversity of needle-related percutaneous interventional procedures that are applicable to the clinical management of patients with liver lesions, such as biopsy of focal lesions, drainage of abscesses, and ablation of tumors. Despite a reasonable safety and efficacy associated with these procedures, there are always grounds of further improvement in techniques and technology of needle-related percutaneous procedures to achieve an even better outcome. It was hypothesized that the application of needle-related interventional radiology to clinical management of focal liver lesions could be facilitated and extended with advancement and refinement in needle-related techniques and technology. This thesis was based on a series of nine studies that aimed to explore the potential of needle-related percutaneous interventions in the clinical management of focal liver lesions and to study the effect of the introduction of innovations in needle-related techniques and technology on such clinical applications. It was concluded that the hypothesis was confirmed. / Yu Chun Ho. / "April 2006." / Adviser: Anil Ahuja. / Source: Dissertation Abstracts International, Volume: 68-08, Section: B, page: 5176. / Thesis (M.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (p. 219-235). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / School code: 1307.
58

DISTRESS AND HEALTH INFORMATION INTERESTS OF WOMEN FOLLOWING A BENIGN BREAST BIOPSY

Steffens, Rachel Fancher 01 January 2008 (has links)
Benign breast biopsy (BBB) can be a stressful experience for many women. Few studies have examined the specific aspects of the BBB more and less distressing. However, no research studies have examined demographic and clinical variables as they relate to distress associated with specific aspects of the BBB or the informational interests of women following a BBB. This study evaluated the magnitude of distress associated with each aspect of the BBB (additional mammography, waiting for the results of the mammography, being informed of needing a biopsy, etc.) as well as the clinical (family history of BC in first degree relative, history of BBB, and type of biopsy) and demographic (age and education) variables as correlates of distress associated with each aspect of a BBB. Additionally, we examined health information interests in women following a BBB and the manner in which women preferred to have this health information communicated.
59

Core biopsy guiada por ultra-som de lesões suspeitas (BI-RADS® 4 E 5) de mama: quantos fragmentos são necessários?

Laporte, Bruno Eduardo Pereira 17 June 2015 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-06-29T11:04:55Z No. of bitstreams: 1 brunoeduardopereira.pdf: 1461941 bytes, checksum: 91aae0fd48e25bdc7d9b2092a649b994 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-08-07T21:49:24Z (GMT) No. of bitstreams: 1 brunoeduardopereira.pdf: 1461941 bytes, checksum: 91aae0fd48e25bdc7d9b2092a649b994 (MD5) / Made available in DSpace on 2017-08-07T21:49:24Z (GMT). No. of bitstreams: 1 brunoeduardopereira.pdf: 1461941 bytes, checksum: 91aae0fd48e25bdc7d9b2092a649b994 (MD5) Previous issue date: 2015-06-17 / A alta acurácia da core biopsy (CB) em diagnosticar câncer em lesões mamárias já é amplamente comprovada. Porém, o número necessário de fragmentos que deve ser obtido para alcançar este objetivo, em lesões BIRADS® 4 e 5, ainda não está estabelecido. Objetivo: Avaliar quantos fragmentos são necessários, em CB guiada por ultrassom (US) de lesões suspeitas de câncer BI-RADS® 4 (B4) e 5(B5), para o diagnóstico de malignidade. Método: Foram selecionadas 59 pacientes consecutivas, com 66 lesões mamárias maiores ou iguais a 1 cm, classificadas em B4 ou B5, e, posteriormente, encaminhadas ao Serviço de Mastologia do Hospital Universitário da Universidade Federal de Juiz de Fora para realização de CB guiada por US. As biópsias foram realizadas por 01 operador, utilizando aparelho de ultrassom com sonda linear de 10 MHz e 01 modelo de pistola de biópsia automática, com agulhas de 14 gauge (GA) e excursão de 12 ou 22 mm. Um total de 5 disparos foram realizados em cada lesão. A cada disparo, o fragmento retirado foi colocado em um frasco exclusivo, recebendo a identificação de acordo com a ordem dos disparos e analisado histopatologicamente. Todos os fragmentos provenientes dos disparos foram incluídos no estudo, mesmo aqueles que obtiveram pouco tecido ou aqueles que não atingiram a lesão. Os resultados anatomopatológicos (AP) das CB foram classificados em benignos ou malignos. Os classificados como malignos correspondiam àqueles com diagnóstico de carcinoma in situ ou invasivo. Os demais foram classificadas como benignos. Os AP das CB foram comparados com os resultados da parafina proveniente de exérese cirúrgica ou com a estabilidade no follow up das lesões. Resultados: A média de idade das pacientes é de 52,6 (± 13,9) anos. CB com diagnóstico de malignidade foi encontrado em 59,4% e de benignidade em 40,6% das biópsias realizadas. Em relação à classificação das lesões, de acordo com o BI-RADS®, 43 (67,2%) lesões foram classificadas como B4 e 21 (32,8%) como B5. O tempo médio de follow up para as 8 pacientes que não realizaram exérese cirúrgica foi de 19,13 meses. Houve 100% de concordância entre o resultado AP do 1º fragmento com o AP da biópsia cirúrgica ou com o follow up das lesões benignas que foram acompanhadas. Conclusão: A retirada de 1 fragmento foi suficiente para o correto diagnóstico de malignidade e benignidade em CB guiadas por US de lesões classificadas como B4 ou B5 com tamanho igual ou superior a 1 cm. / Core biopsy (CB) is widely attested to provide high accuracy for the detection of breast cancer in breast lesions. However, the number of specimens that are required to achieve this in Breast Imaging-Reporting and Data System (BIRADS®) 4 and 5 lesions is yet to be determined. Objective: To evaluate the number of specimens required to diagnose malignancy when using ultrasound (US)-guided CB for BI-RADS® 4 (B4) and 5 (B5) suspected breast cancer lesions. Methods: We selected 59 consecutive patients who were referred to the Mastology Service of the University Hospital of the Federal University of Juiz de Fora for US-guided CB. These patients had 66 breast lesions that measured 1 cm or larger and were classified as B4 or B5. A single operator performed the biopsies, using an ultrasound device with a 10-MHz linear probe, 1 automatic biopsy gun model, 14-gauge needles and 12- or 22-mm excursion. A total of 5 cores were taken from each lesion. The fragment obtained from each biopsy was placed in a separate vial, identified according to the order in which it was taken, and submitted to histopathologic analysis. All the fragments obtained from the biopsies were included in this study, even those that provided small amounts of tissue or resulted from biopsies that had missed the lesion. The CB specimen’s anatomopathological findings were classified as benign or malignant. The CB specimens classified as malignant had a corresponding diagnosis of in situ or invasive carcinoma. The remaining CB specimens were classified as benign. The CB specimens’ anatomopathological findings were compared to those obtained from surgically resected and paraffinised specimens or the lesion’s stability during follow-up consultations. Results: The average patient age was 52.6 (± 13.9) years. Malignancy was diagnosed in 59.4% of the CB specimens, and 40.6% were classified as benign. Regarding the BI-RADS® classifications of the lesions, 43 (67.2%) lesions were classified as B4 and 21 (32.8%) were classified as B5. The average duration of follow-up for the 8 patients who did not undergo surgical resection was 19.13 months. There was 100% agreement between the anatomopathological findings from the first fragment and the anatomopathological findings from the surgical biopsy or the follow-up of the benign lesions. Conclusion: A biopsy of 1 fragment was sufficient for the correct diagnosis of malignant and or benign status in USguided CBs of lesions that were classified as B4 or B5 and measured 1 cm or larger.
60

Refinements and innovations in biopsy and analysis techniques for pleural and lung disease

Diacon, Andreas Henri 12 1900 (has links)
Thesis (PhD (Medicine. Internal medicine))--University of Stellenbosch, 2007. / 1.1. Background Tumors arising from the lung, pleura, or chest wall are a frequent problem in clinical pulmonary medicine. Most lesions are either infectious, neoplastic or granulomatous in nature, but a variety of other differential diagnoses must be considered. An accurate diagnosis is important because the available treatments differ substantially, and because any delay will impair the prognosis in potentially curable patients with lung carcinoma. The investigations involve the disciplines of radiology, pulmonology, surgery, microbiology, and anatomical pathology and consume a respectable amount of resources. The aim of the work covered in this thesis was to optimize the available diagnostic methods for the routine use in a health care setting with limited resources. 1.2. Methods The general idea of this work was to identify conventional sampling methods that could be developed further to become more useful for the diagnosis of chest tumors in a low resource health care setting. The key method was research performed: a) to revise and expand the indication for a sampling method, b) to technically improve the sampling process, and c) to optimize sample transport, preparation and analysis in collaboration with the analytical laboratory. 1.3. Results A list of invasive diagnostic procedures, imaging methods and analytical processes were developed, evaluated and integrated into clinical practice. A) transbronchial needle aspiration, B) transthoracic cutting needle biopsy, C) transthoracic fine needle aspiration, D) transthoracic ultrasound, and E) rapid on-site evaluation of needle aspirates by a cytopathologist. Five studies pertaining to this thesis were published in international peerreviewed journals: â ¢ Safety and yield of ultrasound-assisted transthoracic biopsy performed by pulmonologists (Respiration 2004;71:519-22) This paper established that ultrasound-assisted transthoracic biopsy performed by pulmonologists is feasible, safe, practical, low-cost and has a high yield. â ¢ Utility of rapid on-site evaluation of transbronchial needle aspirates (Respiration 2005;72:182-8) This paper demonstrated the economical advantages of on-site evaluation of transbronchial specimens in a low-resource setting. â ¢ Transbronchial needle aspirates: comparison of two preparation methods (Chest 2005;127:2015-8) This paper demonstrated that preparing smears on-site has a far better yield than pooling samples into a vial. This means that the yield is improved over the current standard at no additional cost. â ¢ Transbronchial needle aspirates: how many passes per target site? (European Respiratory Journal 2007;29:112-6) This paper investigated the most economical and effective approach to serial sampling with transbronchial needle aspiration during flexible bronchoscopy. â ¢ Ultrasound assisted transthoracic biopsy: fine needle aspiration or cutting needle biopsy? (European Respiratory Journal 2007;29:357-62) This paper compared two common methods of sampling and demonstrates that the less expensive method is sufficient in the majority of cases. 1.4. Conclusion This work has impacted on current practice in multiple ways. Conventional methods have been optimized by improving technical factors and with the integration of interdisciplinary collaboration. The initiated research is ongoing with the aim to achieve continued technical and economical improvements in the diagnosis of chest tumors.

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