In vivo MRI thermometry using a phase-sensitive sequence: preliminary experience during MRI-guided laser-induced interstitial thermotherapy of brain tumors.
The purpose of this study was the application of the proton-resonance-frequency method to monitor laser-induced interstitial thermotherapy (LITT) in a patient with an astrocytoma WHO II. A phase-sensitive two-dimensional (2D) fast low-angle shot (FLASH) sequence was used to determine the temperature-related phase shifts during LITT. Temperature maps were displayed during therapy with a temporal resolution of 20 seconds. Irradiation was discontinued as soon as the 60 to 65 degrees C isotherm reached the margin of the tumor. A contrast-enhanced MRI study performed immediately after therapy showed a good correlation of the size of an enhancing rim around the lesion with the 60 to 65 degrees C isotherm. The preliminary results of our study indicate that MRI guidance of LITT may be improved by temperature quantification based on the proton-resonance-frequency method.
Kahn
T
T
Institute of Diagnostic Radiology, Heinrich-Heine-University, Düsseldorf, Germany. kahn@mr.uni-duesseldorf.de
Harth
T
T
Kiwit
J C
JC
Schwarzmaier
H J
HJ
Wald
C
C
Mödder
U
U
D001254:Astrocytoma / Q000473:pathology / Q000628:therapy*; D001921:Brain / Q000473:pathology; D001932:Brain Neoplasms / Q000473:pathology / Q000628:therapy*; D006801:Humans; D006979:Hyperthermia, Induced / Q000379:methods*; D053685:Laser Therapy; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015642:Radiology, Interventional