STEREOTAXIC BIOPSY FOR INTRINSIC LESIONS OF THE MEDULLA THROUGH THE LONG-AXIS OF THE BRAIN-STEM - TECHNICAL CONSIDERATIONS

The authors report the technique and results for stereotactic biopsy o f intrinsic lesions of the medulla oblongata through the long-axis of the brainstem. Multi-planar stereotactic magnetic resonance imaging an d/or reformatted computed tomography imaging is used for coordinate de termination and trajectory selection and facilitates a completely intr a-axial pathway through critical neural tissue. Two patients with smal l, solitary, enhancing lesions of the medulla had stereotactic samplin g via this approach performed under local anesthesia. There was no mor bidity and in both the patients a histologic diagnosis of lymphoma was obtained. We believe that with high-resolution, multi-planar stereota ctic imaging, small lesions in the medulla can safely be biopsied, avo iding the need for either posterior fossa craniectomy and open biopsy, or for empiric management.