Physical Sciences, Sunnybrook Research Institute, Toronto, Ontario, Canada.
Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada.
Magn Reson Med. 2018 Oct;80(4):1588-1594. doi: 10.1002/mrm.27136. Epub 2018 Feb 9.
To investigate the feasibility of performing large FOV hyperpolarized C metabolic imaging using simultaneous multislice excitation.
A spectral-spatial multislice excitation pulse was constructed by cosine modulation and incorporated into a C spiral imaging sequence. Phantom and in vivo pig experiments were performed to test the feasibility of simultaneous multislice data acquisition and image reconstruction. In vivo cardiac-gated images of hyperpolarized pyruvate, bicarbonate, and lactate were obtained at 1 × 1 × 1 cm resolution over a 48 × 48 × 24 cm FOV with 2-fold acceleration in the slice direction. Sensitivity encoding was used for image reconstruction with both autocalibrated and numerically calculated coil sensitivities.
Simultaneous multislice images obtained with 2-fold acceleration were comparable to reference unaccelerated images. Retained SNR figures greater than 80% were achieved over the part of the image containing the heart.
This method is anticipated to enable large FOV imaging studies using hyperpolarized C substrates, with an aim toward whole-body exams that have to date been out of reach.
研究使用同时多层激发进行大视野高极化 13 C代谢成像的可行性。
通过余弦调制构建了一个谱-空域多层面激发脉冲，并将其纳入 13 C螺旋成像序列中。进行了体模和活体猪实验，以测试同时多层数据采集和图像重建的可行性。在 1×1×1 cm 分辨率下，对 48×48×24 cm 的大视野进行了心脏门控的高极化丙酮酸、碳酸氢盐和乳酸成像，在层面方向上实现了 2 倍加速。使用自动校准和数值计算的线圈灵敏度进行了灵敏度编码的图像重建。
2 倍加速获得的同时多层图像与参考未加速图像相当。在包含心脏的图像部分，保留的 SNR 数值大于 80%。
该方法有望实现使用高极化 13 C 底物的大视野成像研究，目标是进行迄今为止无法实现的全身检查。
