Tanaya Mandal

tanaya [at] ece.ubc.ca

575 Course Project Report

3dlivewire_based_segmentation_and_modeling_of_softpalate.pdf

Soft Palate Modeling Summary

Preprocessing	Segmentation	Postprocessing	Surface Reconstruction	Results
Cropping, N3 intensity inhomogeneity correction, Cubic interpolation	3D livewire	Morphological operations, Active contour smoothing	1. Amira 2.Reconstruction of 3D surface from non-parallel contour network	1. 3D surface is not very smooth 2.Smoother surface is reconstructed, but details are ignored

Tools/Softwares used

MIPAV (Medical Image Processing, Analysis and Visualization Tool) - Freeware

3D Livewire

Amira

Ctr2Suf - Freeware

MATLAB

About Ctr2Suf

Ctr2Suf can reconstruct a 3D surface from cross-sectional curves. It uses an input file (.contour) which is a contour network of non-parallel curves and generates mesh. The 3D livewire output file ContourDB.mat can be used to create the .contour file.

My observations:

1. The software seems to crash if number of contours are too many, so downsampling of contours is required (sometimes it crashes even with the contour networks provided with the software itself)

2. Contours are also required to be smooth, too wiggly contours are not treated well

3. Contours must have intersection points, at least two intersection points, else, the contour will be discarded

4. The reconstructed surface can be saved either in .ply or in .suf format. Only .ply is compatible to AMIRA.

Probable improvements (source code for Ctr2Suf was not available):

1. In the coronal view, the soft palate appears in two isolated parts in some slices; this produces two contours in the same plane. Ctr2Suf does not seem to handle more than one contours that belong to the same plane.

2. A comparison with standard mesh can be provided

Literature

M. Poon, G. Hamarneh, R. Abugharbieh. “Efficient Interactive 3D Livewire Segmentation of Complex Objects with Arbitrary Topology”. Computerized Medical Imaging and Graphics, 2008, volume 32, issue 8, pp. 639–650.

T. McInerney and D. Terzopoulos, Deformable models in medical image analysis: a survey, Medical Image Analysis, 2004, vol.8, pp. 35-46.

L. Liu, C. Bajaj, J. O. Deasy, D. A. Low and T. Ju, Surface reconstruction from non-parallel curve networks, Eurographics, 2008, vol. 27, no. 2, pp. 155-163.

M. Kass, A. Witkin and D. Terzopoulos, Snakes: active contour models, Int. Journal of Computer Vision, 1988, vol. 1, pp. 321-331.