Accurate quantification of cerebral blood flow (CBF) is essential for the diagnosis and assessment of a wide range of neurological diseases. Positron emission tomography (PET) with radiolabeled water (15O-water) is considered the gold-standard for the measurement of CBF in humans. PET imaging, however, is not widely available because of its prohibitive costs and use of short-lived radiopharmaceutical tracers that typically require onsite cyclotron production. Magnetic resonance imaging (MRI), in contrast, is more readily accessible and does not involve ionizing radiation. This study presents a convolutional encoder-decoder network with attention mechanisms to predict gold-standard 15O-water PET CBF from multi-sequence MRI scans, thereby eliminating the need for radioactive tracers. Inputs to the prediction model include several commonly used MRI sequences (T1-weighted, T2-FLAIR, and arterial spin labeling). The model was trained and validated using 5-fold cross-validation in a group of 126 subjects consisting of healthy controls and cerebrovascular disease patients, all of whom underwent simultaneous $15O-water PET/MRI. The results show that such a model can successfully synthesize high-quality PET CBF measurements (with an average SSIM of 0.924 and PSNR of 38.8 dB) and is more accurate compared to concurrent and previous PET synthesis methods. We also demonstrate the clinical significance of the proposed algorithm by evaluating the agreement for identifying the vascular territories with abnormally low CBF. Such methods may enable more widespread and accurate CBF evaluation in larger cohorts who cannot undergo PET imaging due to radiation concerns, lack of access, or logistic challenges.
翻译:对大脑血液流动进行准确量化对于诊断和评估广泛的神经神经疾病至关重要;用放射性标签水(15O-水)进行活性排放透析(PET)被认为是测量人体脑血液流动的金标准;然而,由于PET成像成本高昂,使用寿命短的放射药物追踪器,通常需要现场生产环流;磁共振成像(MRI)比较容易获得,不涉及电离辐射;该研究展示了一个配有放射性标签水(15O-水)的电离子排放透析(PET)网络,其关注机制是预测金标准15O-水在人体内测量的金标准(15O-水)光学透析(CET) CBF) CB; 预测模型的输入包括一些常用的辐射药物追踪序列(T1重量、T2-FLAIR和动脉冲旋转标签),相比之下,该模型使用5倍的交叉估值,在126个主题中,包括准确的C-ET数据解算值(C-ET) 和大脑-内流测量(C-IM) 显示一种更先进的直径直径直径直径直径直径直径,因此无法显示这种直径直径直径、直径直径直径、直径、直径直达、直径测、直达、直达、直达、直径直达、直径直径直径直径直达、直达、直达、直达、直径直径直径直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、直达、