Dual source computed tomography: automated, visual or dual analysis?

Excerpt

Over the past years, automated quantitative analysis of the coronary artery system has been developed and successfully clinically applied in particular for X-ray coronary angiography [1]. Recently, computer-aided analysis of the coronary arteries has been developed for ultrasound [2, 3], magnetic resonance imaging (MRI) [4], and lately also for computed tomography (CT) techniques [5, 6]. At present the major bottleneck of multi-slice computed tomography (MSCT) imaging of the coronary arteries is the potential lack of image quality due to limitations in the spatial and temporal resolution, irregular or high heart beat, respiratory effects, and variations of the distribution of the contrast agent. The number of rejected vessel segments in diagnostic studies is currently still too high for implementation in routine clinical practice. Until now, stenoses of the coronary arteries are evaluated visually with CT angiography [7‐33]. Therefore, the results are highly dependent on subjective factors inherent in the examiner. New software tools for semi-quantitative analysis (CT-QCA, quantitative coronary assessment) might be adequate to improve the diagnostic accuracy und reproducibility [6, 34]. However, also for the automated quantitative analysis of the coronary arteries high image quality is required. Based upon the trend in technological development of MSCT scanners, there is no doubt that the quantitative analysis of MSCT coronary angiography will benefit from these technological advances. Fischbach et al. [35] compared quantitative and qualitative information on global and LV function obtained with MSCT with that obtained with resonance imaging (MRI) in patients with a high prevalence of LV wall motion abnormalities in 30 patients with a variety of cardiac disease. Global LV function parameters from MDCT studies were measured using a commercially available software package for cardiac function analysis (CT MASS 6.1, Medis, Leiden, The Netherlands) supporting automatic endo- and epicardial contour detection. Global LV function parameters and wall thickness measurement from MRI studies were determined using the MRI-compatible version of the analysis software (MR MASS suite 6.1, Medis) on an offline workstation employing identical criteria to those used with the CT evaluation. Normokinetic segments were reliably identified with MSCT but the sensitivity for detection and accurate classification of LV wall motion abnormalities need to be improved. Better temporal resolution of the CT system seems to be the most important factor for enhancing MSCT performance. …