Dose Reduction in Pediatric Molecular Imaging

描述（由申请人提供）：医学成像导致的辐射暴露已成为公共安全问题。减少儿科患者的剂量尤为重要，因为此类患者的风险增加，因为其组织的放射敏感性增强，随机辐射效应可能表现的时间较长。本提案的目的是开发和验证可用于最大限度地减少接受分子成像程序的儿科患者的辐射暴露而不会对图像的诊断质量产生不利影响的技术。该提议的假设是，可以通过以下方式减少儿科分子成像患者接收的吸收剂量而不损害研究的图像质量：（1）个体化施用的活动量和图像采集时间，以更好地说明患者特定的身体尺寸和形状可能对探测器计数率密度的影响;（2）调整采集参数以考虑儿科成像中的较小视场;（3）改进图像重建方法以使得能够从这些较低计数、较小视场图像生成图像。在目前的临床实践中，儿科分子成像的给药集中在经验法则方法上，以确定针对不同成像程序给予儿童的活性。通过使用最先进的模拟、图像质量评估和辐射剂量测定工具，本赠款申请中提出的工作将以更严格和科学验证的方式检查剂量降低方法。这种方法将导致临床上可实施的剂量减少技术，用于儿科（和潜在的成人）分子成像，与国家努力减少儿科和成人CT和荧光镜引导的干预剂量，而不会对图像的诊断质量产生不利影响。

DESCRIPTION (provided by applicant): The radiation exposure resulting from medical imaging has become a public safety concern. Dose reduction for pediatric patients is particularly important since such patients are at increased risk owing to the enhanced radiosensitivity of their tissues and the longer time-period over which stochastic radiation effects may manifest. The objective of this proposal is to develop and validate techniques that can be used to minimize the radiation exposure to pediatric patients undergoing molecular imaging procedures without adversely impacting the diagnostic quality of the images. The hypothesis of this proposal is that it is possible to reduce the absorbed dose received by pediatric molecular imaging patients without compromising the image quality of the study by: (1) individualizing the amount of administered activity and the image acquisition time to better account for the effects that patient-specific body size and shape may have on the detector count-rate density; (2) adjusting acquisition parameters to account for the smaller field of view in pediatric imaging; (3) improving image reconstruction methods to enable image generation from these lower-count, smaller field-of-view images. In current clinical practice, dosing for pediatric molecular imaging has focused on rule-of-thumb approaches to identifying the activity administered to children for different imaging procedures. By using state-of-the-art simulation, image quality evaluation and radiation dosimetry tools, the work proposed in this grant application will examine dose reduction methods in a much more rigorous and, scientifically validated manner. This approach will lead to clinically implementable dose reduction techniques for pediatric (and potentially adult) molecular imaging on par with national efforts to reduce doses in pediatric and adult CT and fluoroscopically guided interventions without adversely impacting the diagnostic quality of the images.