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Updated: Feb 4, 2026

Intracranial Implantation with Subsequent 3D In Vivo Bioluminescent Imaging of Murine Gliomas
Published on: November 6, 2011
3D high-resolution imaging of 2-hydroxyglutarate in glioma patients using DRAG-EPSI at 3T in vivo
Zhongxu An1, Vivek Tiwari1, Jeannie Baxter1
1Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas.
Purpose:
To develop 3D high-resolution imaging of 2-hydroxyglutarate (2HG) at 3T in vivo.
Methods:
Echo-planar spectroscopic imaging with dual-readout alternated-gradients (DRAG-EPSI), which was recently reported for 2D imaging of 2HG at 7T, was tested for 3D imaging of 2HG at 3T. The frequency drifts and acoustic noise induced by DRAG-EPSI were investigated in comparison with conventional EPSI. Four patients with IDH-mutant gliomas were enrolled for 3D imaging of 2HG and other metabolites. A previously reported 2HG-tailored TE 97-ms PRESS sequence preceded the DRAG-EPSI readout gradients. Unsuppressed water, acquired with EPSI, was used as reference for multi-channel combination, eddy-current compensation, and metabolite quantification. Spectral fitting was conducted with the LCModel using in-house basis sets.
Results:
With gradient strength of 4 mT/m and slew rate of 20 mT/m/ms, DRAG-EPSI produced frequency drifts smaller by 5.5-fold and acoustic noise lower by 25 dB compared to conventional EPSI. In a 19-min scan, 3D DRAG-EPSI provided images of 2HG with precision (CRLB <10%) at a resolution of 10 × 10 × 10 mm3 for a field of view of 240 × 180 × 80 mm3 . 2HG was estimated to be 5 mM in a pre-treatment patient. In 3 post-surgery patients, 2HG estimates were 3-6 mM, and the 2HG distribution was different from the water-T2 image pattern or highly concentrated in the post-contrast enhancing region.
Conclusion:
Together with 2HG-optimized PRESS, DRAG-EPSI provides an effective tool for reliable 3D high-resolution imaging of 2HG at 3T in vivo.
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