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Segmentation of 3D Tubular Structures. Paul Hernandez-Herrera Computational Biomedicine Lab Advisor: Ioannis A. Kakadiaris and Manos Papadakis. Motivation. Tubular structures appear in biomedical images Neuron Vessels Coronary arteries Airways. Challenges. Size. Challenges.
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Segmentation of 3D Tubular Structures Paul Hernandez-Herrera Computational Biomedicine Lab Advisor: Ioannis A. Kakadiaris and Manos Papadakis
Motivation • Tubular structures appear in biomedical images • Neuron • Vessels • Coronary arteries • Airways
Challenges • Size
Challenges • Intensity
Challenges • Noise
Challenges • Contrast
Thesis Objectives • Develop a binary segmentation algorithm able to • handle different sizes • work with any acquisition modality • deal with noise in the image • handle anisotropic images • do a fast segmentation • have minimum or null user interaction
Thesis Objectives • Develop a centerline algorithm able to • Correctly extract the morphology • Handle overlapping structures • connect gaps • Fast extraction
Pipeline Step 2: Feature extraction Input: 3D image stack Radius Step 1: Background voxels detection Step 4: Segmentation Step 3: Background enhancement
Segmentation as one-class classification Detect voxels in background Train a model (Cost function) Input: 3D image Radius Accepted as Background Feature vectors Get cost value Rejected as Background Voxelswith unknown label These are foreground voxels
Step1: Background voxel detection • Compute the Laplacian of the 3D image • The output has the following properties • Negative values in the foreground • Value close to zero in the boundary • It is positive near but outside the TS • Ringing (positive and negative) in the background
Step 2: Feature extraction • Feature vector • Eigenvalues of Hessian matrix
Step 3: Cost function • Approximate feature vectors distribution for background voxels • Normalize the distribution • Smooth the normalized distribution
Step 3: Background enhancement Input image Enhanced image
Step 4: Segmentation Enhanced image Segmentation
Results: Multiphoton Input Segmentation
Results: Confocal Input Segmentation
Results: Brain vessels Input Segmentation
Ongoing work • Automatic radius estimation • Allow the proposed method to handle any number of features • Centerline extraction
Thanks Thanks for your attention QUESTIONS?