DSA image enhancement via multi-resolution motion correction for interventional procedures: a robust strategy

Visualization of blood vessels during X-ray based interventional procedures is hindered by patient motion and noise in the X-ray imaging systems. This degrades the image quality in Operating Room (OR) procedures. This paper presents a two step strategy to improve the image quality: (a) compensates the motion and (b) enhances the vessels thereby suppressing the background. We minimize the motion artifacts by first registering the bolus images to mask images using B-spline based inverse-consistent image registration method. In step (b), we use two class-based strategies: piecewise and nonlinear, to gradually suppress background noise thereby enhancing the blood vessels and preserving its translucency. The two step enhancement method was tested on 73 different subjects depicting several anatomies such as: brain, carotid and renal. The presented method was compared with the existing methods using signal-to-noise ratio over all the datasets. Our experimental protocol demonstrated consistency between both methods and a significant improvement of both enhancement strategies (SNR improvement of 49.21% for piecewise normalization and 66.44% for nonlinear normalization) compared to conventional methods. We validated our system using GE's PMMA phantoms. The system works on PC using C++.