Registered image subtraction for CT-, MR- and coronary angiography

Abstract

Conventional post-processing of digital subtraction angiography (DSA) by 3D spiral CT, 3D MRI and 2D DSA is often hampered by extended artefacts due to patient movements during examination. In this paper an image registration procedure prior to the digital subtraction is introduced allowing an enhanced visualization of the contrast agent. The object displacement is detected by analysis of image deformations in small local regions. The motion pattern is used to compute a new synthetic mask of maximum congruence with the contrast medium image. This new mask image is then used in the subsequent subtraction. The algorithm works fully automatically and does not need any interactive placement of landmarks. Results obtained from subtraction of uncorrected and corrected sequences were compared with each other. The registration procedure provided good results in the suppression of subtraction artefacts and in the enhancement of vascular structures. Results are presented from subtraction of 2D and 3D data from CTA, MR mammography and coronary angiography.

Diagnostic Accuracy of CT Angiography with Matched Mask Bone Elimination for Detection of Intracranial Aneurysms: Comparison with Digital Subtraction Angiography and 3D Rotational Angiography

“…7,8,[14][15][16][17][18][19] Drawbacks of these methods are the complexity of use, dependence on the user, or high dose of radiation.…”

Bone-Subtraction CT Angiography: Evaluation of Two Different Fully Automated Image-Registration Procedures for Interscan Motion Compensation

“…Therefore, we recommend using bone subtraction to depict and present vascular pathology but suggest that morphologic measurements should always be performed on the original CTA data. An approach that could overcome this problem has been described by Beier er al, 22 who introduced an elastic warping method for (2D) image registration on a section-bysection basis to separate vessels from surrounding bone. Runtime was a major drawback, ranging from 1 to 2 hours per dataset.…”

Differentiation between Chondroma and Squamous Cell Carcinoma: Evaluation of Subtraction Image of MRI.

“…The image processing procedure like digital subtraction angiography (DSA), a technique to eliminate unwanted and confusing shadows, has become widely applied as a visual aid in imaging diagnosis [2]. The image obtained by digitally subtracting an unenhanced image from a contrastenhanced image reflects the distribution of the contrast agent [3].…”