MAGNETIC-RESONANCE-IMAGING OF TEMPERATURE-CHANGES DURING INTERSTITIALMICROWAVE-HEATING - A PHANTOM STUDY

Changes in magnetic resonance (MR) signals during interstitial microwa ve heating are reported, and correlated with simultaneously acquired t emperature readings from three fiber-optic probes implanted in a polya crylamide gel phantom. The heating by a MR-compatible microwave antenn a did not interfere with simultaneous MR image data acquisition. MR ph ase-difference images were obtained using a fast two-dimensional-gradi ent echo sequence. From these images the temperature-sensitive resonan t frequency of the H-1 nuclei was found to decrease approximately by 0 .008 ppm/degrees C. The method and results presented here demonstrate that noninvasive MR-temperature imaging can be performed simultaneousl y with interstitial microwave thermal treatment. (C) 1997 American Ass ociation of Physicists in Medicine.