Accurate MR-based PET Attenuation Correction for Quantitative Clinical Trials

用于定量临床试验的基于 MR 的准确 PET 衰减校正

• 批准号: 9134110
• 负责人: RAYMOND F MUZIC
• 金额: $ 60.25万
• 依托单位: CASE WESTERN RESERVE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-01 至 2019-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9134110
• 关键词: Abdomen; Address; Air; American College of Radiology Imaging Network; Anatomy; Area; Atlases; Attenuated; Brain; Cancer Patient; Cerebellum; Chest; Childhood; Choline; Clinic; Clinical; Clinical Research; Clinical Trials; Clinical Trials Cooperative Group; Collaborations; Complex; Data; Data Set; Dementia; Detection; Diagnostic; Electrons; Enrollment; Environment; Exhibits; FOLH1 gene; Fatty acid glycerol esters; Goals; Head and neck structure; Histocompatibility Testing; Hybrids; Hydrogen; Image; Image Analysis; Imagery; Institution; Legal patent; Lesion; Liver; Lung; Magnetic Resonance Imaging; Malignant neoplasm of prostate; Maps; Measurement; Metastatic breast cancer; Methods; Molecular; Monitor; National Cancer Institute; New Agents; Operative Surgical Procedures; PET/CT scan; Patients; Pattern Recognition; Pelvis; Performance; Photons; Physiologic pulse; Population; Positron-Emission Tomography; Radiation Oncology; Randomized; Recruitment Activity; Reference Standards; Scanning; Signal Transduction; Staging; Support System; System; Techniques; Therapeutic Intervention; Time; Tissues; Translating; Translations; Tumor Pathology; Vendor; Water; Work; attenuation; base; bone; density; diagnostic accuracy; falls; gray matter; image processing; imaging modality; improved; in vivo; lymph nodes; malignant breast neoplasm; meetings; metabolomics; new technology; novel; patient population; prevent; programs; public health relevance; soft tissue; symposium; treatment response; whole body imaging; working group

 DESCRIPTION (provided by applicant): PET/MR is a hybrid imaging modality that combines the exquisite soft tissue contrast of MR with the molecular information of PET. In order to utilize PET/MR in a clinical trial setting, images must be quantitatively accurate, and be reproducible across vendor platforms and institutions. Accurate MR-based attenuation correction (MR- AC) is currently a technical barrier to accomplishing these goals. A specific challenge is differentiating bone from air. While these tissue types have dramatic differences in the degree to which they attenuate photons, they both have negligible signal with conventional MR pulse sequences. Consequently, current MR-AC methods exhibit SUV errors of 20% or greater, particularly in areas within and adjacent to bone, and therefore, current PET/MR scanners do not meet the SUV accuracy required by NCI/ACRIN for clinical trials qualification. Ultra-short echo time (UTE) MR can capture signal in bone prior to its rapid signal decay and is a promising approach to achieve more accurate MR-AC. However, current UTE approaches have low image quality, clinically impractical acquisition times, and a field of view that is too limited for whole-body imaging. The goal of this academic-industrial collaboration is to address these current limitations of UTE by developing accurate and clinically practical methods for whole-body MR-AC, further refining novel and patented methods developed by our working group. The specific aims to realize the goal: 1) Develop novel MR acquisition methods that maximize tissue information regarding photon attenuation for whole-body imaging. We will use our preliminary work in brain as a starting point, which employs an undersampled UTE-Dixon acquisition. 2) Establish image processing methods for determining photon attenuation on a voxel-level. Pattern recognition methods will be developed to analyze the combination of features extracted from the UTE- Dixon data sets. The photon attenuation will be estimated on a continuous scale reflecting the fractional composition of different tissue types within each voxel and also by directly mapping to CT values. 3) Demonstrate clinical feasibility of the above proposed MR-based attenuation correction methods. Clinical scanning with a commercial PET/MR system will be performed in a cancer patient population comparing the developed MR-AC methods to CT-AC values for SUV accuracy, image quality, and diagnostic accuracy. By bringing together cutting-edge advances in both MR acquisition and image analyses, the successful completion of these aims will achieve SUVs that are within 5% of those obtained with PET/CT (reference standard) with clinically appropriate acquisition time, image quality, and diagnostic accuracy, capable of supporting quantitative clinical trials with commercial PET/MR systems.

 描述（由应用提供）：PET/MR是一种混合成像方式，将MR的独特软组织对比与PET的分子信​​息结合在一起。为了利用 PET/MR在临床试验环境中，图像必须定量准确，并且可以在供应商平台和机构中重现。准确的基于M的衰减校正（MR-AC）目前是实现这些目标的技术障碍。一个具体的挑战是区分 空气中的骨头。尽管这些组织类型在减弱照片的程度上具有巨大的差异，但它们都具有常规的MR脉冲序列的信号可忽略不计。因此，当前的MR-AC方法暴露于20％或更高的SUV误差，尤其是在骨骼内部和附近的区域，因此，当前的PET/MR扫描仪不符合NCI/ACRIN对于临床试验资格的NCI/ACRIN所需的SUV准确性。 Ultra-Short Echo Time（UTE）MR可以在其快速信号衰减之前捕获骨骼中的信号，并且是实现更准确的MR-AC的有望方法。但是，当前的UTE方法的图像质量较低，临床上不切实际的采集时间以及一个观点，而对于全身成像而言过于限制。这种学术工业合作的目标是解决这些当前的限制 通过为全身MR-AC开发准确和临床实用的方法，进一步完善了我们的工作组开发的新颖和专利的方法。具体目的是实现目标：1）开发新型的MR采集方法，以最大程度地提高有关全身成像光子衰减的组织信息。我们将在大脑中使用初步工作作为起点，该工作是雇员的Ute-Dixon收购。 2）建立用于确定体素级别光子衰减的图像处理方法。将开发模式识别方法来分析从Ute-Dixon数据集提取的特征的组合。光子衰减将以连续的比例估算，反映每个体素内不同组织类型的分数组成，并直接映射到CT值。 3）证明了上述基于MR的衰减校正方法的临床可行性。使用商业宠物/MR系统进行临床扫描将在癌症患者人群中进行，将开发的MR-AC方法与CT-AC值进行比较，以获得SUV准确性，图像质量和诊断准确性。通过将MR采集和图像分析的最先进的进步汇总在一起，这些目标的成功完成将实现SUV，这些SUV占使用PET/CT（参考标准）获得的5％以内的SUV，具有适当的临床获取时间，图像质量和诊断准确性，能够支持商业PET/MR Systems的定量临床试验。