Stereotactic indications for neuroradiological differential diagnosis.

The modern neurodiagnostic techniques of MR imaging, CT scanning and angiography provide valuable morphological information that, although highly sensitive to tumour localisation, still lacks comparable specificity as to the exact histological nature of those lesions demonstrated. Biopsy remains necessary. To patients with potentially inoperable lesions or lesions best treated by chemotherapy or irradiation, modern techniques of neurosurgery now offer the option of precise stereotactic biopsy through small twist-drill burr holes as opposed to open biopsy. The interrelationships between MR, CT, angiography and stereotactic biopsy and their respective roles in the establishment of a definitive diagnosis are discussed.