[Stereotactic intervention as a contribution to diagnosis and therapy of paramedian processes]

In open brain surgery, access to processes in the midline region is difficult. Exact diagnosis of the tumour type is crucial to the choice of therapeutic modality. In many cases, modern imaging procedures such as CT and MRI are useful diagnostic tools. The diagnosis is confirmed by direct biopsy and histological examination. Selected cases of tumours close to the midline (germinoma, pilocytic astrocytoma, primary cerebral malignant lymphoma) are presented. CT and MRI are helpful in demonstrating space-occupying processes. The tumour's histological type is determined by CT-stereotactic biopsy. The histopathological diagnosis is established by means of a crush preparation. Appropriate forms of therapy are proposed on the basis of the diagnosis of tumour type. The results are impressive, due to the efficacy of stereotactic procedures as an additional means of diagnosing and treating space-occupying processes of the midline region.