Modern stereotactic surgical procedures were developed mainly because digital CT image gave us the opportunity to recognize the morphology and the site of a brain lesion, and, at the same time, CT offered a very easy and reliable way to calculate target coordinates because the brain scans are digital maps. Digital x-ray image obtained with an x-ray-intensifier and a TV Analog/Digital converter is not suitable for stereotactic use because image distortion is multifactorial and it is impossible to rectify. We have developed a new apparatus (Neurogil) for intra-operative use that is able to produce a digital image on a display, the measures displayed match exactly with the patient's brain. A linear array of 1024 photodiodes is working in front of an x-ray source and it collects the density image of the patient's head positioned between them. It shows the patient's head with the stereotactic frame exactly as a radiogram, but no distortion is present. Digital brain angiograms are possible with electronic subtraction, mathematical enhancement and with a stereoscopic view on a particular display. Any kind of mathematical calculation or computer-graphic application is possible. A special software was developed for stereotactic closed and open surgery.
Cephalometry Cerebral Angiography