First in-human evaluation of [1- 13 C]pyruvate in D 2 O for hyperpolarized MRI of the brain: A safety and feasibility study

• Published in: Magnetic resonance in medicine Vol. 91; no. 6; pp. 2559 - 2567
• Main Authors: Deh, Kofi, Zhang, Guannan, Park, Angela Hijin, Cunningham, Charles H, Bragagnolo, Nadia D, Lyashchenko, Serge, Ahmmed, Shake, Leftin, Avigdor, Coffee, Elizabeth, Hricak, Hedvig, Miloushev, Vesselin, Mayerhoefer, Marius, Keshari, Kayvan R
• Format: Journal Article
• Language: English
• Published: United States 01.06.2024
• Subjects: Brain - diagnostic imaging; Carbon Isotopes; Feasibility Studies; Humans; Magnetic Resonance Imaging - methods; Pyruvic Acid; Solvents; brain; deuterium oxide (D2O); hyperpolarized 13C‐pyruvate
• ISSN: 0740-3194; 1522-2594
• DOI: 10.1002/mrm.30002

To investigate the safety and value of hyperpolarized (HP) MRI of [1- C]pyruvate in healthy volunteers using deuterium oxide (D O) as a solvent. Healthy volunteers (n = 5), were injected with HP [1- C]pyruvate dissolved in D O and imaged with a metabolite-specific 3D dual-echo dynamic EPI sequence at 3T at one site (Site 1). Volunteers were monitored following the procedure to assess safety. Image characteristics, including SNR, were compared to data acquired in a separate cohort using water as a solvent (n = 5) at another site (Site 2). The apparent spin-lattice relaxation time (T ) of [1- C]pyruvate was determined both in vitro and in vivo from a mono-exponential fit to the image intensity at each time point of our dynamic data. All volunteers completed the study safely and reported no adverse effects. The use of D O increased the T of [1- C]pyruvate from 66.5 ± 1.6 s to 92.1 ± 5.1 s in vitro, which resulted in an increase in signal by a factor of 1.46 ± 0.03 at the time of injection (90 s after dissolution). The use of D O also increased the apparent relaxation time of [1- C]pyruvate by a factor of 1.4 ± 0.2 in vivo. After adjusting for inter-site SNR differences, the use of D O was shown to increase image SNR by a factor of 2.6 ± 0.2 in humans. HP [1- C]pyruvate in D O is safe for human imaging and provides an increase in T and SNR that may improve image quality.