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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.

As doenças benignas da mama respondem pela maior parte dos diagnósticos em patologia mamária, por esse motivo têm se tornado um problema crescente na prática clínica pela limitação diagnóstica atual em identificar o subgrupo de lesões com maior potencial de risco par neoplasia invasora. O estudo das lesões proliferativas com marcadores prognósticos do câncer de mama mostrou que o estrogênio exerce papel importante na transformação dessas lesões, através do seu receptor nuclear, induzindo a transcrição de genes, mas também pelo receptor de membrana citoplasmática, estimulando a proliferação celular através da ativação das proteína-quinases ativadas por mitógenos. Trabalhos experimentais com culturas de células de diferentes linhagens, incluindo células mamárias, identificaram a proteína S100P, uma proteína ligante de cálcio, como participante da transformação neoplásica maligna e diferenciação celular. No presente trabalho, estudamos a expressão da S100P, do receptor de estrogênio e avaliamos a proliferação celular de 155 pacientes submetidas à biópsia mamária por agulha grossa assistida a vácuo, guiada por estereotaxia, população que corresponde à rotina diagnóstica em patologia mamária. Comprovamos a associação do receptor de estrogênio com as lesões pré-malígnas, classificadas segundo seu potencial de risco para neoplasia invasora, principalmente em mulheres abaixo dos 50 anos. Demonstramos haver forte associação entre a S100P e o receptor de estrogênio na distinção do potencial de risco das lesões histológicas, confirmando o papel importante da S100P no processo de transformação maligna. Observamos que a ausência da proteína torna praticamente nula a possibilidade de progressão tumoral, e mais ainda que sua ação depende também do receptor de estrogênio / The benign breast diseases represent the major diagnose in breast pathology, so they have became an increasing problem concerning the clinical practice for limited capability diagnosis to identify a subgroup in this category with greater risk to evolve to invasive breast cancer. Studies with proliferative breast lesions and prognostic markers of breast cancer have shown that estrogen plays an important roll in malignant transforming process through its nuclear receptor which activates the transcriptional process. Moreover, the surface estrogen receptor stimulates the cell proliferation as a result of activation of mitogen-activated protein-kinases cascade. In vitro experiments with differents cell lines, including breast cell ones, have identified a protein, called S100P, a calcium-binding protein, as participating of the malignant transforming process and cell differentiation. In the present work, we studied the immunoexpression expression of S100P, estrogen receptor and evaluated the cell proliferation of 155 patients submitted to vacuum assisted core biopsy with stereotactic guidance of breast, a population that corresponds to the routine diagnose in breast pathology. We have proved the association between estrogen receptor and premalignant lesions, stratified by the relative risk for developing invasive breast cancer, mainly among women under the 50 years. We also have demonstrated a strong association of S100P and estrogen receptor concerning the distinctive relative risk of breast histologic lesions; bring up the important contribution of S100P in the carcinogenetic process. Meanwhile, the presence of S100P rises up the transforming possibility. We finally have found that the action of S100P depends on the estrogen receptor status

As doenças benignas da mama respondem pela maior parte dos diagnósticos em patologia mamária, por esse motivo têm se tornado um problema crescente na prática clínica pela limitação diagnóstica atual em identificar o subgrupo de lesões com maior potencial de risco par neoplasia invasora. O estudo das lesões proliferativas com marcadores prognósticos do câncer de mama mostrou que o estrogênio exerce papel importante na transformação dessas lesões, através do seu receptor nuclear, induzindo a transcrição de genes, mas também pelo receptor de membrana citoplasmática, estimulando a proliferação celular através da ativação das proteína-quinases ativadas por mitógenos. Trabalhos experimentais com culturas de células de diferentes linhagens, incluindo células mamárias, identificaram a proteína S100P, uma proteína ligante de cálcio, como participante da transformação neoplásica maligna e diferenciação celular. No presente trabalho, estudamos a expressão da S100P, do receptor de estrogênio e avaliamos a proliferação celular de 155 pacientes submetidas à biópsia mamária por agulha grossa assistida a vácuo, guiada por estereotaxia, população que corresponde à rotina diagnóstica em patologia mamária. Comprovamos a associação do receptor de estrogênio com as lesões pré-malígnas, classificadas segundo seu potencial de risco para neoplasia invasora, principalmente em mulheres abaixo dos 50 anos. Demonstramos haver forte associação entre a S100P e o receptor de estrogênio na distinção do potencial de risco das lesões histológicas, confirmando o papel importante da S100P no processo de transformação maligna. Observamos que a ausência da proteína torna praticamente nula a possibilidade de progressão tumoral, e mais ainda que sua ação depende também do receptor de estrogênio / The benign breast diseases represent the major diagnose in breast pathology, so they have became an increasing problem concerning the clinical practice for limited capability diagnosis to identify a subgroup in this category with greater risk to evolve to invasive breast cancer. Studies with proliferative breast lesions and prognostic markers of breast cancer have shown that estrogen plays an important roll in malignant transforming process through its nuclear receptor which activates the transcriptional process. Moreover, the surface estrogen receptor stimulates the cell proliferation as a result of activation of mitogen-activated protein-kinases cascade. In vitro experiments with differents cell lines, including breast cell ones, have identified a protein, called S100P, a calcium-binding protein, as participating of the malignant transforming process and cell differentiation. In the present work, we studied the immunoexpression expression of S100P, estrogen receptor and evaluated the cell proliferation of 155 patients submitted to vacuum assisted core biopsy with stereotactic guidance of breast, a population that corresponds to the routine diagnose in breast pathology. We have proved the association between estrogen receptor and premalignant lesions, stratified by the relative risk for developing invasive breast cancer, mainly among women under the 50 years. We also have demonstrated a strong association of S100P and estrogen receptor concerning the distinctive relative risk of breast histologic lesions; bring up the important contribution of S100P in the carcinogenetic process. Meanwhile, the presence of S100P rises up the transforming possibility. We finally have found that the action of S100P depends on the estrogen receptor status

計算機超聲引導針放置模擬系統近年受到醫學界密切關注。在過去十年，為應付各種需要，大量模擬系統被研發。與傳統訓練方法比較，使用計算機模擬系統作訓練擁有多種優點。例如：可控訓練環境，能重複使用的數據庫，以及客觀評核。至今，研究的主要方向依然是物理建構的模擬。雖然，更真實及更仔細的模擬系統能引發新的教學概念，系統開發的重點應該著眼於對訓練的影響。 / 本論文研究計算機超聲引導針放置模擬系統的最新發展。首先，我們會介紹計算機模擬系統的各個範疇及於醫學訓練的基本應用。使用計算機模擬系統作訓練用途的成效會被討論。然後，我們會討論幾種針對訓練成效的改進技術。這些技術包括一個動態訓練場景生成框架，綜合遊戲概念的方法，以及一種以臨床技術為本的穿刺提示規劃法則。它們對訓練的影響利用實驗作驗證。接著，我們介紹一個評核穿刺軌跡可視化技術的框架。我們的研究發現，穿刺軌跡的可視化技術對用家放置針的準確度有顯著的影響。這意味著模擬系統中穿刺軌跡的可視化技術需要經過非常小心的設計。最後，我們介紹一個超聲材質的描述器。這個描述器針對超聲材質的比較而設計。超聲材質的比較不止是在超聲模擬系統中重要的一環，更能被應用在各種醫學圖像的研究中。 / Computer-based ultrasound guided needle placement simulators have gained extensive attention of the medical society. In the last decade, a lot of simulators have been proposed to suit different purposes. Advantages of using computer-based simulators over traditional training include controlled training environment, reusable case database and objective evaluation. Yet, the most studied aspect of computer-based simulators remains the simulation of physical situations. Though a more realistic and detailed simulation enables new training concepts, the origin of any development shall be its effect on training. / This thesis studies the latest development of computer-based ultrasound guided needle placement simulators. We first introduce basic aspects of computer-based simulators and their applications on medical training. The effects on computer-based training over traditional methods are discussed. Secondly, we present various techniques that aim for effective training. These techniques include a framework for dynamic case generation, an integration of serious game concepts, and a recommendation scheme based on clinical practices. Their impacts on training are evaluated through various experiments. Thirdly, we present an evaluation framework for the visualization of needle access pathway. Our study shows that the adoption of visualization techniques significantly affects users' performance of needle alignment. This implies that a careful design of the visual effect inside a simulator is necessary. Lastly, we present a descriptor for ultrasound textures. This descriptor is designed for ultrasound textural comparison which is an important step for not only ultrasound simulators but also other medical imaging applications. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Chan, Wing Yin. / Thesis (Ph.D.) Chinese University of Hong Kong, 2014. / Includes bibliographical references (leaves 100-114). / Abstracts also in Chinese. / Chan, Wing Yin.