Fig. 1

Repeatability of deuterium metabolic imaging (DMI) was investigated in six healthy volunteers. Uptake of glucose and its conversion into lactate, water, and glutamine + glutamate (Glx) was examined after oral intake of 75 g of [6,6-²H₂]-glucose. The imaging was repeated four times for two sessions 6 weeks apart (a). Each examination consisted of T1-weighted imaging and ²H chemical shift imaging resulting in a 10 × 10 × 10 grid of spectra (b). Each spectrum was fitted to water, glucose, lactate, and Glx peaks. Here, a single spectrum from the cortex is shown (c). All peaks increased in amplitude over time (d); the solid line is a second-degree polynomial fit on the individual data points from the two sessions pooled. The glucose and lactate peaks reached plateau between 75 and 120 min, while the water and Glx peaks continued to increase close to linearly