The Wave Controlled Aliasing In Parallel Imaging (Wave-CAIPI) technique manifests great potential to highly accelerate three-dimensional (3D) balanced steady-state free precession (bSSFP) through substantially reducing the geometric factor (g-factor) and aliasing artifacts of image reconstruction. However, severe banding artifacts appear in bSSFP imaging due to unbalanced gradients with nonzero 0th moment applied by the conventional Wave-CAIPI technique. In this study, we propose a 3D Wave-bSSFP scheme that adopts truncated wave gradients with zero 0th moment to avoid introducing additional banding artifacts and to maintain the advantages of wave encoding. The simulation results indicate that the number of wave cycles that are truncated and different options of applying wave gradients affect both the g-factor reduction and image quality, but the influence is limited. In phantom experiments, the proposed technique shows similar acceleration performance as the conventional Wave-CAIPI technique and effectively eliminates its introduced banding artifacts. Additionally, Wave-bSSFP obtains up to 12×12\times retrospective acceleration at 0.8 mm isotropic resolution in in vivo 3D brain experiments and is superior to the state-of-the-art Controlled Aliasing In Parallel Imaging Results IN Higher Acceleration (CAIPIRINHA) technique, according to both visual validation and quantitative analysis. Moreover, in vivo 3D spine and abdomen imaging demonstrate the potential clinical applications of Wave-bSSFP with fast acquisition speed, improved isotropic resolution and fine image quality.

中文翻译：

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使用具有截断波梯度的修正波 CAIPI 技术加速 3D bSSFP


并行成像中的波控混叠 (Wave-CAIPI) 技术通过大幅减少图像的几何因子 (g 因子) 和混叠伪影，展现出高度加速三维 (3D) 平衡稳态自由进动 (bSSFP) 的巨大潜力重建。然而，由于传统 Wave-CAIPI 技术应用的非零零矩的不平衡梯度，bSSFP 成像中出现严重的带状伪影。在本研究中，我们提出了一种 3D Wave-bSSFP 方案，该方案采用零阶矩为零的截断波梯度，以避免引入额外的带状伪影并保持波编码的优势。仿真结果表明，被截断的波周期数和应用波梯度的不同选项都会影响 g 因子的降低和图像质量，但影响有限。在模型实验中，所提出的技术表现出与传统的 Wave-CAIPI 技术相似的加速性能，并有效地消除了其引入的带状伪影。此外，Wave-bSSFP 在体内 3D 脑实验中以 0.8 mm 各向同性分辨率获得高达 12×12 倍的回顾性加速度，并且优于最先进的并行成像结果中的受控混叠更高加速度 (CAIPIRINHA)技术，根据视觉验证和定量分析。此外，体内3D脊柱和腹部成像证明了Wave-bSSFP的潜在临床应用，具有快速的采集速度、改进的各向同性分辨率和精细的图像质量。