3-DIMENSIONAL DENSITOMETRIC RECONSTRUCTION AND VISUALIZATION OF STENOSED CORONARY-ARTERY SEGMENTS

In this paper we report results from an ongoing study about the diagno stic benefits of three-dimensional (3D) visualization and quantificati on of stenosed coronary artery segments. Biplane angiographic images d o not provide enough information for the exact reconstruction of the c oronary arteries. Therefore, a priori information about the 3D shape t o be reconstructed must be incorporated into the reconstruction algori thm. One approach is to assume a circular cross-section of the coronar y artery. Hence, the diameter is estimated from the contours of the ve ssel in both projections. Another approach is based on densitometry an d searches for a solution of the reconstruction problem close to the p reviously reconstructed adjacent slice. In this paper we apply contour information as well as the densitometrical profiles of the two orthog onal vessel projections. We present a new probabilistic densitometric reconstruction algorithm, which extends the correct handling of the st ochastic properties of the density profiles into the network flow base d reconstruction algorithm. The reconstructed coronary segment is visu alized in three dimensions. In order to assess the accuracy of the rec onstruction, the method is applied to tubes with artificial obstructio n of known geometry, modeling coronary artery stenoses. These catheter tubes are filled with normal iodine contrast material. The results of the reconstruction and visualization are discussed with respect to cl inical usefulness.