Volume reconstructions made up of a stack of computed tomographic (CT) images are displayed as a volume image using the method of numerical reprojection. Reprojection involves the generation, in a computer, of two-dimensional digital radiographs of the reconstructed volume taken from any desired angle of view. They are formed by summing the x-ray density values of the individual volume picture elements (voxels) of the reconstruction along the set of paths which project the 3-D volume onto a plane. Stereo-pair reprojection images generated at two angles of view differing by 2 degree to 6 degree are utilized to visualize the volume image in three dimensions. Display of a ″stack″ of CT images in this manner may result in the obscuring of some anatomic features due to superposed dense structures. The obscuring effect of superposition is overcome by selective enhancement of the anatomic features of interest in the 3-D image. These enhancement methods are selective ″tissue dissolution″ and ″numerical dissection″ whereby portions of the reconstructed volume are either partially dissolved or totally eliminated from the reconstructed volume before reprojection to enhance the visibility of desired structure. Because they operate on the 3-D data before projection image, they are both effective and highly selective as visual enhancement methods.
|Number of pages
|Applied Scientific Research (The Hague)
|Published - Jan 1 1979
|Conf on Comput Appl in Radiol & Comput/Aided Anal of Radiol Images, 6th, Proc - Newport Beach, CA, USA
Duration: Jun 18 1979 → Jun 21 1979
ASJC Scopus subject areas