Dynamic deuterium metabolic imaging in glioblastoma at 7T

Abstract Objective This study investigates the dynamic metabolic characteristics of glioblastoma (GBM) using Deuterium Metabolic Imaging (DMI) at 7 T, aiming to dynamically characterize the Warburg effect in vivo. Material and methods Five newly diagnosed GBM patients underwent dynamic DMI prior to any treatment. 3D 2 H free-induction-decay (FID)-Magnetic resonance spectroscopy imaging (MRSI) measurements (11:44 min per scan) were performed at 7 T during ~ 100 min following [6,6’- 2 H 2 ]glucose consumption. Venous plasma glucose and plasma 2 H-Glc atom percent enrichment (APE) levels were measured during the scan. Brain 2 H-glucose ( 2 H-Glc), 2 H-Glutamate/Glutamine ( 2 H-Glx), 2 H-Lactate ( 2 H-Lac), 2 H-Lac/ 2 H-Glx were analyzed with a two-level (time and tissue type) Linear Mixed Model. Results Brain 2 H-Glc levels were similar across tissue types. 2 H-Glx was significantly lower in tumors compared to normal appearing brain tissue (NABT) ( p < 0.01). 2 H-Lac was significantly higher in tumors compared to NABT ( P < 0.01). The 2 H-Lac/ 2 H-Glx ratio provided tumor-specific contrast, starting 40-50 min post [6,6’- 2 H 2 ]glucose consumption. Venous plasma glucose and 2 H-Glc APE increased within 50 min and venous 2 H-Glc APE stabilized at ~ 60%. Discussion Dynamic DMI at 7 T reveals metabolic alterations in GBM, particularly through the 2 H-Lac/ 2 H-Glx ratio. This contrast was primarily driven by decreased 2 H-Glx rather than profoundly increased 2 H-Lac. These findings support the utility of DMI in assessing metabolic reprogramming in brain tumors.