Research On Coronary Artery Reconstruction Algorithm Based On Fusion Of IVUS And CAG

Intravascular ultrasound imaging and coronary angiography are two most widely used techniques in coronary disease diagnosis clinically.They play very important roles in medical pictures,especially those used for diagnosing coronary artery disease.Intravascular ultrasound can only provide the internal data of the diseased blood vessels,while X-ray coronary angiography only preserves important spatial geometry information of the vessels.So,fusion utilization of the two techniques can provide complete data,including both inside and outside information of blood vessels.Fusion of the two kinds of images will provide more abundant evidence for coronary disease diagnosis and the next research work.The reconstruction of coronary artery means vascular remodeling by fusion of corresponding IVUS and CAG.The reconstruction study mainly include the next parts: media-adventitia border segmentation of IVUS,lumen extraction and registration of CAG,reconstruction of the vessel trajectory,fusion of IVUS and CAG.Especially,the reconstruction of vessel trajectory and IVUS orientation in the fusion of IVUS and CAG play a great role in the reconstruction result.For further improving the accuracy of reconstruction result and operating speed,this paper put forward two new approaches after analyzing procedures in the reconstruction of vessel trajectory and fusion of IVUS and CAG.The spatial vessel trajectory reconstruction is the base of fusion of IVUS and CAG.And the conventional solution to resolve the 3-dimensional vessel trajectory is that the key space points of trajectory are fitted by Spline curves.For further improving the smooth and reconstruction speed of vessel trajectory,this paper put forward a new approach called intersect surfaces.It is different from the ways of space point fitting.In the intersect surface approach,we firstly fitted the key points of vessel trajectory in 2-dimensional plane,and then the vessel lines were pulled into surfaces.Finally,the 3-dimensional vessel trajectory was calculated by intersect surfaces.Classical IVUS orientation solution is the algorithm called Relative angle calculation first.It worked out the relative angles,rotated the IVUS,and then calculated the absolute angle of the first IVUS.Lastly,all the IVUS were rotated on the basis of the absolute angle.For improvement of effect of reconstruction result and velocity in experimental environments,this paper put forward an approach based on the multiple computing of the absolute angles.This way is different from the way called relative angle computing first.It finished the angle rotation of IVUS by computing all the absolute angles separately.In this paper,after extraction,registration,and curve fitting of CAG vessel trajectory,we finished constructing the contour profile of vessels using our new approaches and completed the reconstruction by s urface fitting.The experimental results show that the two ways we put forward are feasible and effective.