Stereotaxic biopsy of the brain under MR imaging control.

Stereotaxic biopsy under computed tomographic (CT) control has become a routine procedure in neurosurgical practice and has a high degree of accuracy with a low morbidity [14]. Magnetic resonance (MR) imaging has some advantages over CT in studying the brain and may reveal cerebral lesions where little or no sign is evident with CT [5, 6] . The MR imaging features not seen with CT are usually well localized although in pathologic terms they are often nonspecific. These findings have provided a strong stimulus for the development of stereotaxic biopsy techniques suitable for MR imaging, in part to exploit the new diagnostic information and in part to achieve a better understanding of its significance. Leksell et al. [7, 8] recently described a stereotaxic system suitable for use with MR imaging as well as the use of conventional MR imaging to confirm the location of bilateral lesions produced in the thalami under CT guidance, but the use of MR imaging-guided stereotaxic biopsy in clinical practice has not been reported previously. We describe a different type of stereotaxic biopsy system suitable for use with MR imaging and illustrate its use in two clinical cases.