Dual Component Analysis for In Vivo T₂* Decay of Hyperpolarized ¹³C Metabolites.
10.13104/imri.2017.21.1.1
- Author:
Eunhae JOE
1
;
Joonsung LEE
;
Hansol LEE
;
Seungwook YANG
;
Young Suk CHOI
;
Eunkyung WANG
;
Ho Taek SONG
;
Dong Hyun KIM
Author Information
1. Department of Electrical and Electronic Engineering, Yonsei University, Seoul, Korea. donghyunkim@yonsei.ac.kr
- Publication Type:Original Article
- Keywords:
Hyperpolarized ¹³C;
Metabolic imaging;
T₂* relaxation time;
[1-¹³C];
pyruvate;
[1-¹³C] lactate
- MeSH:
Animals;
Brain;
Lactic Acid;
Magnetic Resonance Spectroscopy;
Membranes;
Mice;
Pyruvic Acid
- From:Investigative Magnetic Resonance Imaging
2017;21(1):1-8
- CountryRepublic of Korea
- Language:English
-
Abstract:
PURPOSE: To investigate the exchange and redistribution of hyperpolarized ¹³C metabolites between different pools by temporally analyzing the relative fraction of dual T₂* components of hyperpolarized ¹³C metabolites. MATERIALS AND METHODS: A dual exponential decay analysis of T₂* 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 T₂* components are explored when fitted from averaged spectrum and temporal variations of their fractions. RESULTS: The T₂* values were not significantly different between the tumor and control groups, but the fraction of longer T₂* [1-¹³C] lactate components was more than 10% in the tumor group over that of the controls (P < 0.1). The fraction of shorter T₂* 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 T₂* component was always greater than the longer T₂* 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 T₂* 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.
