Computational sciences and nuclear medicine imaging

核医学成像技术以其分子特性和特殊的灵敏度，在现代医学中发挥着重要的作用。通过提供关于放射性同位素标记的示踪分子生物分布的体内功能信息，它们不仅可以识别改变的解剖和功能，以帮助诊断疾病，而且还可以定位分子受体位置，研究疾病细胞表达的生物标志物，并监测特定疾病过程的存在和程度。医学影像研究小组(MIRG)的研究计划的主要目标是利用高等物理学、数学和计算机科学(这里统称为“计算科学”)来开发新的和改进的诊断核医学方法，这些方法既适用于日常临床实践，也适用于医学和分子研究。Mirg的研究涉及几个密切相关的领域：定量成像、动态功能成像、数据分析和可视化，以及新成像技术的研究。我们未来的一些目标包括：(1)开发基于统一定量SPECT方法(QSPECT)的精确剂量学技术，结合自动三维体积分割例程(基于Level-Set及类似方法)和详细的蒙特卡罗计算伽马光子、X射线和电子产生的能量沉积所产生的内部剂量，(2)进一步研究采用不同正则化方案的现代数学优化技术的应用，以重建多维动态图像序列，(3)开发软件，构建和测试康普顿相机。基于探测康普顿散射光子并使用固态探测器的新一代相机可能提供真正的亚毫米分辨率的分子成像手段(目标是为特定细胞成像)。

Nuclear medicine imaging techniques, with their molecular characteristics and exceptional sensitivity, play an important role in modern medicine. By providing in-vivo functional information about the biodistribution of tracer molecules labeled with radioactive isotopes, they allow not only for identification of altered anatomy and function to help diagnose disease, but also for locating molecular receptor sites, studying biological markers expressed by diseased cells, and monitoring the presence and extent of specific disease processes. The main objective of the research program of the Medical Imaging Research Group (MIRG) is to use advanced physics, mathematics and computer science (jointly called here "Computational Sciences") to develop new and improved methods for diagnostic nuclear medicine, ones suitable for use both in everyday clinical practice and in medical and molecular research. MIRG's research is in several closely related areas: quantitative imaging, dynamic functional imaging, data analysis and visualization, and the investigation of novel imaging techniques. Some of our future goals include: (1) the development of an exact dosimetry technique based on our unified quantitative SPECT method (qSPECT) combined with an automatic 3-D volume segmentation routine (level-set based and similar methods) and detailed Monte-Carlo calculations of internal dose due to energy deposition by gamma photons, X-rays and electrons, (2) further research on the application of modern mathematical optimization techniques with different regularization schemes to reconstruct a multidimensional series of dynamic images, (3) development of software, construction and testing of a Compton camera. The new generation of cameras, based on detection of Compton scattered photons and using solid state detectors can potentially provide means for truly molecular imaging with sub-millimeter resolution (with the goal to image particular cells).