Border detection of fetal Nuchal translucency for automated ultrasonic measurement

Abstract

Ultrasonic measurement of NT thickness is currently performed by manually tracing the two echogenic lines and placing the sonogram calipers on the inner edges of these lines. The drawbacks of this method are inter- and intraobserver variability, and its inefficiency. We present a computerized method of detecting the border of the NT layer for automated ultrasonic measurements by minimizing a cost function using dynamic programming. Local measurements of intensity, edge strength and continuity are extracted and become weighted terms in a cost function. The dynamic programming is used for finding a global optimum for a cost function. Our method provides superior results in terms of accuracy and reproducibility. © International Federation for Medical and Biological Engineering 2007.