Computational sciences and nuclear medicine imaging

核医学成像技术以其分子特性和卓越的灵敏度在现代医学中发挥着重要作用。通过提供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结构和功能以帮助诊断疾病，还可以定位分子受体位点，研究病变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）研究项目的主要目标是利用先进的物理、数学和计算机科学（这里统称为“计算科学”）开发新的和改进的核医学诊断方法，这些方法既适合于日常临床实践，也适合于医学和分子研究。MIRG的研究在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，以及新型成像技术的研究。我们未来的目标包括：(1)基于我们的统一定量SPECT方法（qSPECT），结合自动三维体积分割程序（基于水平集和类似方法）和详细的伽马光子、x射线和电子能量沉积引起的内剂量蒙特卡罗计算，开发精确剂量测定技术；(2)进一步研究了不同正则化方案的现代数学优化技术在多维序列动态图像重构中的应用；(3)康普顿相机的软件开发、构建和测试。基于康普顿散射光子探测和使用固态探测器的新一代相机，有可能提供亚毫米分辨率的真正分子成像手段（目标是成像特定细胞）。

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).