Advances in medical imaging with current cross-section modalities enable non-invasive characterization of adrenal lesions. Computed tomography (CT) provides characterization with its non-contrast and wash-out features...Advances in medical imaging with current cross-section modalities enable non-invasive characterization of adrenal lesions. Computed tomography (CT) provides characterization with its non-contrast and wash-out features. Magnetic resonance imaging (MRI) is helpful in further characterization using chemical shift imaging (CSI) and MR spectroscopy. For differentiating between benign and malignant masses, positron emission tomography (PET) imaging is useful with its qualitative analysis, as well as its ability to detect the presence of extra-adrenal metastases in cancer patients. The workup for an indeterminate adrenal mass includes evaluation with a non-contrast CT. If a lesion is less than 10 Hounsfield Units on a non-contrast CT, it is a benign lipid-rich adenoma and no further work-up is required. For the indeterminate adrenal masses, a lipid-poor adenoma can be differentiated from a metastasis utilizing CT wash-out features. Also, MRI is beneficial with CSI and MR spectroscopy. If a mass remains indeterminate, PET imaging may be of use, in which benign lesions demonstrate low or no fluorodeoxyglucose activity. In the few cases in which adrenal lesions remain indeterminate, surgical sampling such as percutaneous biopsy can be performed.展开更多
Long plasma channels in air induced by femtosecond laser pulses are inves-tigated using three different methods, including the cross-section imaging, resistivity measuring and acoustic diagnostics. These methods are b...Long plasma channels in air induced by femtosecond laser pulses are inves-tigated using three different methods, including the cross-section imaging, resistivity measuring and acoustic diagnostics. These methods are based on different properties of the light filaments. A comparison of the three diagnostics shows that the imaging method is the most precise one in studying the filaments distribution and evolution, that the sono-graphic method is the most convenient approach to detecting long plasma channels by detecting the acoustic wave generation, and that the resistivity measurement can only be applied for giving a rough estimate. The diagnostics of filaments allow us to choose ap-propriate detecting methods and provide further insight into the dynamic evolution of the light filaments in air.展开更多
文摘Advances in medical imaging with current cross-section modalities enable non-invasive characterization of adrenal lesions. Computed tomography (CT) provides characterization with its non-contrast and wash-out features. Magnetic resonance imaging (MRI) is helpful in further characterization using chemical shift imaging (CSI) and MR spectroscopy. For differentiating between benign and malignant masses, positron emission tomography (PET) imaging is useful with its qualitative analysis, as well as its ability to detect the presence of extra-adrenal metastases in cancer patients. The workup for an indeterminate adrenal mass includes evaluation with a non-contrast CT. If a lesion is less than 10 Hounsfield Units on a non-contrast CT, it is a benign lipid-rich adenoma and no further work-up is required. For the indeterminate adrenal masses, a lipid-poor adenoma can be differentiated from a metastasis utilizing CT wash-out features. Also, MRI is beneficial with CSI and MR spectroscopy. If a mass remains indeterminate, PET imaging may be of use, in which benign lesions demonstrate low or no fluorodeoxyglucose activity. In the few cases in which adrenal lesions remain indeterminate, surgical sampling such as percutaneous biopsy can be performed.
基金the National Natural Science Foundation of China (Grant Nos. 60478047, 10374116 , 10390160)the National Key Basic Research Special Foundation (Grant No. G1999075206) the National Hi-Tech ICF Programme.
文摘Long plasma channels in air induced by femtosecond laser pulses are inves-tigated using three different methods, including the cross-section imaging, resistivity measuring and acoustic diagnostics. These methods are based on different properties of the light filaments. A comparison of the three diagnostics shows that the imaging method is the most precise one in studying the filaments distribution and evolution, that the sono-graphic method is the most convenient approach to detecting long plasma channels by detecting the acoustic wave generation, and that the resistivity measurement can only be applied for giving a rough estimate. The diagnostics of filaments allow us to choose ap-propriate detecting methods and provide further insight into the dynamic evolution of the light filaments in air.