Laser-induced thermal lesions in the human brain: short- and long-term appearance on MRI.

PURPOSE

The purpose of our study was to investigate with MRI the development of thermal lesions in the human brain up to almost 4 years after laser-induced interstitial thermotherapy (LITT).

METHOD

Eighteen patients with brain tumors who underwent LITT entered the study.

RESULTS

In all patients the acute lesion comprised five concentric zones that showed reverse signal intensities on T1- versus T2-weighted images. Lesion development over time was uniform in 89% of the lesions. In two cases variations were observed.

CONCLUSION

The results of our MR follow-up studies showed that post-LITT, laser-induced lesions will shrink exponentially after an initial expansion without any pseudocystic effects.