Informatics in Radiology: Postprocessing Pitfalls in Using CT for Automatic and Semiautomatic Determination of Global Left Ventricular Function

Recent advances in technical capabilities of computed tomographic (CT) scanners, including an increasing number of detector rows, improved spatial and temporal resolution, and the development of retrospective gating, have allowed the acquisition of four-dimensional (4D) datasets of the beating heart. As a result, the heart can be visualized in different phases and CT datasets can be used to assess cardiac function. Many software packages currently exist that allow automatic or semiautomatic evaluation of left ventricular function on the basis of 4D CT datasets. The level of automation varies from extensive, completely manual segmentation by the user to fully automatic evaluation of left ventricular function without any user interaction. Although the reproducibility of functional parameter assessment is reported to be high and intersoftware variability low for larger groups of patients, significant differences can exist among measurements obtained with different software tools from the same dataset. Thus, careful review of automatically or semiautomatically obtained results is required.