Matsubara Keisuke, Ibaraki Masanobu, Shidahara Miho, Kinoshita Toshibumi
Department of Radiology and Nuclear Medicine, Research Institute for Brain and Blood Vessels, Akita Cerebrospinal and Cardiovascular Center, 6-10 Senshu-Kubota-machi, Akita, 010-0874, Japan.
Department of Quantum Science and Energy Engineering, Graduate School of Engineering, Tohoku University, Sendai, Japan.
Radiol Phys Technol. 2020 Dec;13(4):348-357. doi: 10.1007/s12194-020-00591-2. Epub 2020 Oct 19.
Imprecise registration between positron emission tomography (PET) and anatomical magnetic resonance (MR) images is a critical source of error in MR imaging-guided partial volume correction (MR-PVC). Here, we propose a novel framework for image registration and partial volume correction, which we term PVC-optimized registration (PoR), to address imprecise registration. The PoR framework iterates PVC and registration between uncorrected PET and smoothed PV-corrected images to obtain precise registration. We applied PoR to the [C]PiB PET data of 92 participants obtained from the Alzheimer's Disease Neuroimaging Initiative database and compared the registration results, PV-corrected standardized uptake value (SUV) and its ratio to the cerebellum (SUVR), and intra-region coefficient of variation (CoV) between PoR and conventional registration. Significant differences in registration of as much as 2.74 mm and 3.02° were observed between the two methods (effect size < - 0.8 or > 0.8), which resulted in considerable SUVR differences throughout the brain, reaching a maximal difference of 62.3% in the sensory motor cortex. Intra-region CoV was significantly reduced using the PoR throughout the brain. These results suggest that PoR reduces error as a result of imprecise registration in PVC and is a useful method for accurately quantifying the amyloid burden in PET.
正电子发射断层扫描（PET）与解剖磁共振（MR）图像之间的配准不准确是MR成像引导的部分容积校正（MR-PVC）中误差的关键来源。在此，我们提出了一种用于图像配准和部分容积校正的新框架，我们将其称为PVC优化配准（PoR），以解决配准不准确的问题。PoR框架在未校正的PET和平滑后的PV校正图像之间迭代进行PVC和配准，以获得精确配准。我们将PoR应用于从阿尔茨海默病神经影像倡议数据库获得的92名参与者的[C]PiB PET数据，并比较了PoR与传统配准之间的配准结果、PV校正的标准化摄取值（SUV）及其与小脑的比值（SUVR）以及区域内变异系数（CoV）。两种方法之间在配准上观察到高达2.74毫米和3.02°的显著差异（效应大小< -0.8或> 0.8），这导致整个大脑的SUVR存在相当大的差异，在感觉运动皮层中最大差异达到62.3%。使用PoR时，整个大脑的区域内CoV显著降低。这些结果表明，PoR减少了PVC中因配准不准确导致的误差，是一种准确量化PET中淀粉样蛋白负荷的有用方法。
