Rotational Motion in Sensorless Freehand 3d Ultrasound
نویسندگان
چکیده
Freehand 3D ultrasound can be acquired without a position sensor by using image-based positioning methods. In-plane motion can be tracked using image registration between nearby images. Elevational probe motion can be determined from the decorrelation between images. However, a freehand scan involves rotational as well as translational motion, and this affects the decorrelation. If this effect is ignored, it leads to errors in the image-based positions. In this paper, we present a technique to compensate for out-of-plane rotations, which we test using simulations and in vitro experiments. We show that by using this technique, the accuracy of image-based positioning is improved.
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