Applied X-ray photogrammetry in neurosurgery.

The introduction of X-ray stereophotogrammetry into neurosurgery permits the exact localisation of metal-dense foreign bodies, the spatial representation of cerebral tumours and their blood supply. The determination of the target point in stereotactic operations is carried out after adjustment of the reference points on the X-ray picture directly by the computer, the seat of the probe can be seen in the X-ray picture in its spatial relations. For intracranial aneurysms, the position, the size, and the topographic situation of the neck of the aneurysm can be determined, and thus the placing of the clip during the operation can be pre-planned and made simpler and safer. A description of the photographic technique and the interpretation by means of the new stereocomparator of Messrs. Zeiss is given.