ROTATIONAL MOTION IN SENSORLESS FREEHAND 3D ULTRASOUND
R.J. Housden, A.H. Gee, R.W. Prager and G.M. Treece
October 2007
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.
[758 KBytes PDF, 16 pages]
If you have difficulty viewing files that end '.gz'
,
which are gzip compressed, then you may be able to find
tools to uncompress them at the gzip
web site.
If you have difficulty viewing files that are in PostScript, (ending
'.ps'
or '.ps.gz'
), then you may be able to
find tools to view them at
the gsview
web site.
We have attempted to provide automatically generated PDF copies of documents for which only PostScript versions have previously been available. These are clearly marked in the database - due to the nature of the automatic conversion process, they are likely to be badly aliased when viewed at default resolution on screen by acroread.