Automated conduit detection method from a synthetic M-mode using spline curves

Previous studies have shown that correct identification of the conduit border is a crucial factor for an accurate stroke volume measurement. This paper describes a method that automatically defines conduit boundaries from a synthetically generated M-mode image of the left ventricular outflow tract (LVOT). Unlike the existing methods that define conduit boundaries based solely on single-frame analysis, this method uses LVOT boundaries of adjacent frames to measure the conduit diameter. By using spline curves that are generated from the neighboring conduit boundaries, this technique estimates the LVOT diameter even in a noisy image where conduit boundaries are not clear. The conduit diameter calculated by this method shows close agreement with manual measurement by two independent observers.