Low-Resolution Electromagnetic Tomography (LORETA) Source Imaging Compared with Structural Brain Imaging in Patients having Organic Brain Lesion / 신경정신의학

ABSTRACT

OBJECTIVES: Patients with organic brain lesion can produce unique slow waves (delta and theta) in the EEG. Basic assumption of this study was that the low resolution electro magnetic tomography (LORETA), an inverse source localization program, can provide functional images representing increased slow wave activity in these patients compared to normal subjects. METHODS: The current study was performed by 18 channels digital EEG for 10 patients whose organic deficit have been visually confirmed by CT or MRI. The source images of slow wave (1-7 Hz) frequency were produced by LORETA-key program. RESULTS: We found that in eight out of ten subjects, LORETA successfully found out the source regions which were very closely matched to their original brain lesions. However in two subjects whose organic brain lesions were too small (<1 cm) and located out of gray matter, we failed to find any increased slow wave activity compared with normal control. CONCLUSION: We can conclude that LORETA could be a useful method to provide functional imaging in patients with gray matter deficits in their brain. Its usefulness and limitations were discussed.