Premium
T 1 relaxation time at 0.2 Tesla for monitoring regional hyperthermia: Feasibility study in muscle and adipose tissue
Author(s) -
Peller Michael,
Reinl Herbert M.,
Weigel Andreas,
Meininger Martin,
Issels Rolf D.,
Reiser Maximilian
Publication year - 2002
Publication title -
magnetic resonance in medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.696
H-Index - 225
eISSN - 1522-2594
pISSN - 0740-3194
DOI - 10.1002/mrm.10155
Subject(s) - adipose tissue , hyperthermia , in vivo , imaging phantom , ex vivo , muscle tissue , breakpoint , magnetic resonance imaging , biomedical engineering , nuclear magnetic resonance , nuclear medicine , materials science , medicine , chemistry , biology , anatomy , radiology , physics , chromosomal translocation , microbiology and biotechnology , biochemistry , gene
The purpose of this study was to characterize T 1 , particularly in the hyperthermia temperature range (ca. 37–44°C), in order to control regional hyperthermia with MR monitoring using 0.2 Tesla, and to improve T 1 mapping. A single‐slice and a new multislice “T One by Multiple Read‐Out Pulses” (TOMROP) pulse sequence were used for fast T 1 mapping in a clinical MRI hyperthermia hybrid system. Temporal stability, temperature sensitivity, and reversibility of T 1 were investigated in a polyamidacryl gel phantom and in samples of muscle and adipose tissues from turkey and pig, and verified in patients. In the gel phantom a high linear correlation between T 1 and temperature ( R 2 = 0.97) was observed. In muscle and adipose tissue, T 1 and temperature had a linear relationship below a breakpoint of 43°C. Above this breakpoint muscle tissue showed irreversible tissue changes; these effects were not visible in adipose tissue. The ex vivo results were confirmed in vivo under clinical conditions. T 1 mapping allows the characterization of hyperthermia‐related tissue response in healthy tissue. T 1 , in combination with fast mapping, is suitable for controlling regional hyperthermia at 0.2 T within the hybrid system. Magn Reson Med 47:1194–1201, 2002. © 2002 Wiley‐Liss, Inc.