Detection of point landmarks in 3D medical images via phase congruency model
© The Brazilian Computer Society 2011
Received: 16 September 2010
Accepted: 28 February 2011
Published: 19 March 2011
This paper presents a novel technique for detection of point landmarks in volumetric medical images based on a three-dimensional (3D) Phase Congruency (PC) model. A bank of 3D log-Gabor filters is specially designed in the frequency domain and used to compute 3D energy maps, which are further combined to form the phase congruency measure. The PC measure is invariant to intensity variations and contrast resolution and provides a good indication of feature significance in an image. To detect significant 3D point landmarks, eigen-analysis of a 3×3 matrix of second-order PC moments, computed for each point in the image, is performed followed by local maxima detection. Two different application scenarios in radiation therapy planning of the head and neck anatomy are used to illustrate the feasibility and usefulness of the proposed method.