Laser-Induced Thermal Lesions in the Human Brain: Short- and Long-Term Appearance on MRI

Abstract

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.