Division of Radiological Physics, Department of Radiology , University Hospital Basel, Basel, Switzerland.
Department of Biomedical Engineering, University of Basel, Basel, Switzerland.
MAGMA. 2024 Dec;37(6):1047-1057. doi: 10.1007/s10334-024-01194-3. Epub 2024 Aug 6.
To demonstrate the potential of a double angle stimulated echo (DA-STE) method for fast and accurate "full" homogeneous Helmholtz-based electrical properties tomography using a simultaneous magnitude and transceive phase measurement.
The combination of a spin and stimulated echo can be used to yield an estimate of both magnitude and transceive phase and thus provides the means for "full" EPT reconstruction. An interleaved 2D acquisition scheme is used for rapid acquisition. The method was validated in a saline phantom and compared to a double angle method based on two single gradient echo acquisitions (GRE-DAM). The method was evaluated in the brain of a healthy volunteer.
The magnitude obtained with DA-STE showed excellent agreement with the GRE-DAM method. Conductivity values based on the "full" EPT reconstruction also agreed well with the expectations in the saline phantom. In the brain, the method delivered conductivity values close to literature values.
The method allows the use of the "full" Helmholtz-based EPT reconstruction without the need for additional measurements. As a result, quantitative conductivity values are improved compared to phase-based EPT reconstructions. DA-STE is a fast complex- mapping technique that could render EPT clinically relevant at 3 T.
展示一种双角度激发回波（DA-STE）方法的潜力，该方法可通过同时进行幅度和收发相位测量，实现快速、准确的基于全亥姆霍兹的均匀电特性层析成像（EPT）“全”重建。
自旋和激发回波的组合可用于估计幅度和收发相位，从而为“全”EPT 重建提供手段。采用交错 2D 采集方案进行快速采集。该方法在盐溶液体模中进行了验证，并与基于两次单梯度回波采集（GRE-DAM）的双角度方法进行了比较。该方法在健康志愿者的大脑中进行了评估。
DA-STE 获得的幅度与 GRE-DAM 方法具有极好的一致性。基于“全”EPT 重建的电导率值与盐溶液体模中的预期值也非常吻合。在大脑中，该方法提供的电导率值接近文献值。
该方法允许使用“全”亥姆霍兹基 EPT 重建，而无需额外测量。因此，与基于相位的 EPT 重建相比，定量电导率值得到了改善。DA-STE 是一种快速的复数映射技术，可使 EPT 在 3T 下具有临床相关性。
