Preliminary experience with MR-guided thermal ablation of brain tumors.
OBJECTIVE
To evaluate the feasibility of a technique of MR-guided stereotactic radio frequency ablation, which was developed as a minimally invasive treatment for brain tumors, and to determine MR characteristics and sequential evolution of radio frequency lesions created to ablate brain tumors.


METHODS
Fourteen lesions in 12 patients with primary and metastatic brain tumors were treated with this technique and followed for up to 10 months. The stereotactic coordinates of the tumor and the angle of the radio frequency probe were calculated on MR imaging. The radio frequency lesion was generated in the awake patient by increasing the temperature to 80 degrees C within the tumor for 1 minute. This was repeated until the entire tumor volume was destroyed. MR imaging was performed before, during, and immediately after the radio frequency procedure, and sequential MR was obtained during clinical follow-up.


RESULTS
MR imaging clearly showed well-defined radio frequency lesions and provided feedback for treatment planning. The radio frequency lesion boundary was well identified as a dark signal rim on T2-weighted images and showed ring enhancement on contrast-enhanced T1-weighted images. The sequential MR imaging showed the radio frequency lesions decreased in volume in all cases, suggesting focal control.


CONCLUSIONS
Stereotactic MR-guided radio frequency brain tumor ablation is a feasible and promising technique that can be an attractive brain tumor treatment alternative. MR provided not only accurate tumor location but also visualization of feedback of thermal tissue changes that reflected therapeutic effect.
Anzai
Y
Y
Department of Radiological Science, University of California, Los Angeles Medical Center 90024-1721.
Lufkin
R
R
DeSalles
A
A
Hamilton
D R
DR
Farahani
K
K
Black
K L
KL
D000230:Adenocarcinoma / Q000473:pathology / Q000556:secondary / Q000601:surgery; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001932:Brain Neoplasms / Q000473:pathology / Q000556:secondary / Q000601:surgery*; D003287:Contrast Media; D005240:Feasibility Studies; D005246:Feedback; D005500:Follow-Up Studies; D005682:Gadolinium; D005909:Glioblastoma / Q000473:pathology / Q000601:surgery; D006801:Humans; D007089:Image Enhancement; D008279:Magnetic Resonance Imaging / Q000379:methods; D008875:Middle Aged; D009837:Oligodendroglioma / Q000473:pathology / Q000601:surgery; D010347:Patient Care Planning; D015642:Radiology, Interventional; D016634:Radiosurgery / Q000379:methods; D016896:Treatment Outcome
D003287:Contrast Media; D005682:Gadolinium