Patent ID: 6094467
Filing Date: 2000-07-25
Classification: A61B,G06T,Y10S

Abstract:
A method for locating boundaries of metal inserts in an array of attenuation data of a set of CT X-ray attenuation data comprising a plurality of arrays of attenuation data, wherein each array of attenuation data represents attenuation data acquired for a plurality of substantially contiguous paths through a slice of a subject, comprising:(a) evaluating the derivative of the attenuation data with respect to a position coordinate of the array of attenuation data;(b) setting a derivative threshold;(c) identifying positive and negative boundary peaks as positive and negative peaks in the derivative respectively that have an absolute value greater than the derivative threshold;(d) determining the positions of the positive and negative boundary peaks; and(e) determining the position of boundaries of metal inserts in the array of attenuation data to be positions of positive and negative boundary peaks.