Stereotactic measurement of the sizes of arteriovenous malformations.

A method has been devised for determining the size and location of an arteriovenous malformation (AVM), or brain tumor, using only two X-ray films taken perpendicular to each other. For this method the requirements are that the locations of the films and the X-ray sources must be known. Such requirements are met by BIPLANE POLY DIAGNOST I, an X-ray machine in which both the films and the X-ray sources are set at constant locations. An analytic geometry approach is used to analyze the images in order to determine both the size and position of phantoms placed in or on an experimental box. Analysis of the films generated by phantoms yields a result accurate to within 0.3 mm.