A Multi-scale Approach for Crest Line Extraction in 3D Medical Images

Recently, we have shown that the differential properties of the surfaces represented by 3D volumic images can be recovered using their partial derivatives. For instance, the crest lines can be characterized by the first, second and third partial derivatives of the grey levrl function I(x,y,z) . This paper deals with the following points : the computation of the partial derivatives of an image c a n be improved using recursive filters which approximate the Gauss~an filter, a multi-sale approach solves many of the instability problems arising from the computation of the partial derivatives, we illustrate the previous point for the nest line extraction (a crest point is a zero-crossing of the derivative of the maximum curvature along the maximum curvature direction). We present experimental results of crest point extraction on 3-D meclicd data. keywords : volumic JD medical images, surface modelling, curvatures, crest lines, multi-scale derivation, recursive filtering.