Fusion of angiography and intravascular ultrasound in-vivo Establishing the absolute 3-D fr.pdf

Fusion of Angiography and Intravascular Ultrasound In-Vivo: Establishing the Absolute 3-D Frame Orientation Andreas Wahle,  Member, IEEE, Guido P. M. Prause, Clemens von Birgelen, Raimund Erbel, and Milan Sonka, Member, IEEE Abstract — Data fusion of biplane angiography and intravascu- lar ultrasound (IVUS) facilitates geometrically correct reconstruc- tion of coronary vessels. The locations of IVUS frames along the catheter pullback trajectory can be identified, however the IVUS image orientations remain ambiguous. An automated approach to determination of correct IVUS image orientation in 3-D space is reported. Analytical calculation of the catheter twist is followed by statistical optimization determining the absolute IVUS image orientation. The fusion method was applied to data acquired in patients undergoing routine coronary intervention, demonstrat- ing the feasibility and good performance of our approach. Index Terms — Data Fusion, Multimodal 3-D Reconstruction, Biplane Angiography, Intravascular Ultrasound. I. INTRODUCTION For the assessment of atherosclerotic disease, two major imaging modalities are commonly utilized. Quantitative Coro- nary Angiography (QCA) is a well-established standard, for which many semi-automated systems are available [1]–[4]. By using biplane angiography, any spatial structure visible in both projections can be geometrically reconstructed in the 3-D space. Information about the imaging geometry [5]–[7], and the as- signment of corresponding vessel segments between both pro- jections are the prerequisites [8], [9]. Recently, intravascular ultrasound (IVUS) evolved as a complementary method;a com- prehensive overview of the existing methods for IVUS image acquisition and analysis can be found in [10]. While selec- tive angiography depicts the vessel lumen only, IVUS allows to analyze vascular wall and plaque. However, IVUS lacks a geometrically correct 3-D representation since it provides no information about vessel curvature. Curre