Recently, Yao Li’s team from the School of Biomedical Engineering, Shanghai Jiaotong University made a major breakthrough in fast high-resolution metabolism imaging of acute stroke patients. For the first time ever, in an 8-min scan, the team simultaneously obtained 3D maps of N-acetylaspartate and lactate at a nominal spatial resolution 3 mm. The research was published in Brain, a leading journal in brain research, titled “Fast high resolution theoretical imaging of acute stroke with 3D mapping resonance spectroscopy”, and was selected as the cover story in November issue. Brain’s official tweet also posted the findings.

Impaired oxygen and cellular metabolism is a hallmark of ischaemic injury in acute stroke. Magnetic resonance spectroscopic imaging (MRSI) has long been recognized as a potentially powerful tool for non-invasive metabolic imaging. Nonetheless, long acquisition time, poor spatial resolution, and narrow coverage have limited its clinical application. Here we investigated the feasibility and potential clinical utility of rapid, high spatial resolution, near whole-brain 3D metabolic imaging based on a novel MRSI technology. In an 8-min scan, the team simultaneously obtained 3D maps of N-acetylaspartate and lactate at a nominal spatial resolution of 2.0*3.0*3.0 mm³ with near whole-brain coverage from a cohort of 18 patients with acute ischaemic stroke. Serial structural and perfusion MRI was used to define detailed spatial maps of tissue-level outcomes against which high-resolution metabolic changes were evaluated. Within hypoperfused tissue, the lactate signal was higher in areas that ultimately infarcted compared with those that recovered. Both lactate and N-acetylaspartate differed between infarcted and other regions. Within the areas of diffusion-weighted abnormality, lactate was lower where recovery was observed compared with elsewhere. This feasibility study supports further investigation of fast high-resolution MRSI in acute stroke.

The first author and the only corresponding author of this paper is Associate Professor Yao Li. This work took three years, in cooperation with the Department of radiology of Shanghai Fifth People's Hospital, Professor Zhi-Pei Liang’s team from University of Illinois in the United States, and Professor Parashkev Nachev team from University College London in the United Kingdom.

It is supported by the National Natural Science Foundation of China (No. 81871083, No. 61671292) and the Science and Technology Innovation Fund of Shanghai Jiaotong University (No. 2019qya12).