Investig Magn Reson Imaging.  2017 Mar;21(1):1-8. 10.13104/imri.2017.21.1.1.

Dual Component Analysis for In Vivo T₂* Decay of Hyperpolarized ¹³C Metabolites

Affiliations
  • 1Department of Electrical and Electronic Engineering, Yonsei University, Seoul, Korea. donghyunkim@yonsei.ac.kr
  • 2Center for Neuroscience Imaging Research, Institute for Basic Science, Sungkyunkwan University, Suwon, Korea.
  • 3Department of Radiology, College of Medicine, Yonsei University, Seoul, Korea.

Abstract

PURPOSE
To investigate the exchange and redistribution of hyperpolarized ¹³C metabolites between different pools by temporally analyzing the relative fraction of dual Tâ‚‚* components of hyperpolarized ¹³C metabolites.
MATERIALS AND METHODS
A dual exponential decay analysis of Tâ‚‚* is performed for [1-¹³C] pyruvate and [1-¹³C] lactate using nonspatially resolved dynamic ¹³C MR spectroscopy from mice brains with tumors (n = 3) and without (n = 4) tumors. The values of shorter and longer Tâ‚‚* components are explored when fitted from averaged spectrum and temporal variations of their fractions.
RESULTS
The Tâ‚‚* values were not significantly different between the tumor and control groups, but the fraction of longer Tâ‚‚* [1-¹³C] lactate components was more than 10% in the tumor group over that of the controls (P < 0.1). The fraction of shorter Tâ‚‚* components of [1-¹³C] pyruvate showed an increasing tendency while that of the [1-¹³C] lactate was decreasing over time. The slopes of the changing fraction were steeper for the tumor group than the controls, especially for lactate (P < 0.01). In both pyruvate and lactate, the fraction of the shorter Tâ‚‚* component was always greater than the longer Tâ‚‚* component over time.
CONCLUSIONS
The exchange and redistribution of pyruvate and lactate between different pools was investigated by dual component analysis of the free induction decay signal from hyperpolarized ¹³C experiments. Tumor and control groups showed differences in their fractions rather than the values of longer and shorter Tâ‚‚* components. Fraction changing dynamics may provide an aspect for extravasation and membrane transport of pyruvate and lactate, and will be useful to determine the appropriate time window for acquisition of hyperpolarized ¹³C images.

Keyword

Hyperpolarized ¹³C; Metabolic imaging; T₂* relaxation time; [1-¹³C]; pyruvate; [1-¹³C] lactate

MeSH Terms

Animals
Brain
Lactic Acid
Magnetic Resonance Spectroscopy
Membranes
Mice
Pyruvic Acid
Lactic Acid
Pyruvic Acid
Full Text Links
  • IMRI
Actions
Cited
CITED
export Copy
Close
Share
  • Twitter
  • Facebook
Similar articles
    DB Error: unknown error