Technology Development for Medical Imaging

在过去的100年里，医学成像技术有了显著的发展。例如，通过压缩传感、多层CT和飞行时间PET等这些系统的不断发展，导致了能够更好地探测人体以更好地了解疾病的更先进的技术。 我们建议继续研究通过持续的技术发展来推进医学成像。虽然同步PET/MR成像很耐人寻味，但目前它的价格高得令人望而却步，临床应用有限。相比之下，同步SPECT/MR成像是一个可能以显著较低的成本获得更大临床应用的领域。目前，SPECT成像的使用频率大约是PET成像的5倍，而成本大约是PET成像的1/5。此外，虽然PET主要用于肿瘤学或神经学应用，但SPECT有更广泛的使用领域，包括神经学、心脏病学、肿瘤学、泌尿学和胃肠病学应用。 我们之前已经开发了一种使用CZT探测器的MR兼容辐射探测系统。该系统被证明在3T磁共振成像中工作，但需要进一步的研究才能将其发展成真正的同时成像系统。我们将改进数据采集系统，以实现高计数能力，并将开展系统集成和建模工作，以努力提供断层成像能力。需要做大量的工作来开发合适的图像重建算法。 我们还在寻求其他成像策略；其中包括一种用于体内血栓诊断的新技术，例如创伤性脑损伤或深静脉血栓形成(DVT)时的血肿。颅脑损伤或深静脉血栓的诊断通常是在病人出现在急诊室后，使用核磁共振或CT。为了提供更快速的诊断，我们正在开发一种能够非侵入性和无电离辐射地检测血液凝块存在的检测系统。该系统利用光声方法来测量组织中血液的存在。通过利用不同波长的光的光吸收的差异，并通过检测在受到短时间的高强度光脉冲时产生的声波压力波，我们打算在损伤发生后不久诊断血栓的存在。该工具是便携的，由急救人员或家庭从业者携带，他们可以使用它来确定现场是否存在血栓。这一点很重要，因为它允许患者在出现症状之前进行适当的成像或接受治疗，并在前往急诊室的途中。 我们乐观地认为，对这些技术的更多基础科学研究将继续朝着更好的医疗保健方向发展，并将以更低的成本实现新的诊断应用。

Medical imaging has evolved significantly over the past 100 years. Continued development of these systems through, for example, compressed sensing, multi-slice CT, and time-of-flight PET, has led to more advanced techniques able to better probe the human body in an effort to better understand disease. We propose to continue research into advancing medical imaging through continued technological developments. While simultaneous PET/MR imaging is intriguing, it is currently an prohibitively expensive, with limited clinical applications. In contrast, simultaneous SPECT/MR imaging is an area that may have far greater clinical application at significantly lower cost. Presently, SPECT imaging is used approximately 5x more often than PET imaging at approximately 1/5th the cost. As well, while PET is used principally for oncologic or neurological applications, SPECT has a much wider area of use, including neurologic, cardiologic, oncologic, urologic and gastro-enterologic applications. We have previously developed an MR-compatible radiation detection system using CZT detectors. This system was shown to work in a 3T MRI but further research is necessary to develop this into a true simultaneous imaging system. We will improve the data acquisition system to enable high count-rate capability and will perform work on systems integration and modeling in an effort to provide tomographic imaging capability. Significant work is needed into development of appropriate image reconstruction algorithms. We are also pursuing other imaging strategies; among these is a novel technique for the diagnosis of blood clots in vivo, such as hematomas in the case of traumatic brain injury or deep vein thrombosis (DVT). The diagnosis of TBI or DVT is often made after a patient presents to an Emergency Room, using MRI or CT. In order to provide a more rapid diagnosis, we are developing a detection system that is able to detect the presence of blood clots non-invasively and without ionizing radiation. This system utilizes the photoacoustic method in order to measure the presence of blood in tissue. By exploiting differences in the photo-absorption of light at different wavelengths and by detecting the resultant acoustic pressure wave produced when subjected to a brief pulse of highly intense light, we intend to diagnose the presence of blood clots soon after the onset of injury. This tool is intended to be portable and carried by emergency first responders or family practitioners who can use it to determine the presence of clots on site. This is important as it allows the patient to directed to appropriate imaging or to receive treatment prior to appearance of symptoms and enroute to the ER. We are optimistic that additional basic science research into these technologies will continue the trend towards better healthcare and will permit new diagnostic applications at reduced cost.