Liyun Tu1, Martin Styner2, Jared Vicory2, Beatriz Paniagua2, Juan Carlos Prieto3, Dan Yang4, Stephen M Pizer2. 1. Chongqing University, Shapingba, Chongqing, China ; University of North Carolina at Chapel Hill, Chapel Hill NC, USA. 2. University of North Carolina at Chapel Hill, Chapel Hill NC, USA. 3. Brigham and Women's hospital, Center of Neurological Imaging, Boston MA, USA. 4. Chongqing University, Shapingba, Chongqing, China.
Abstract
PURPOSE: Improving the shape statistics of medical image objects by generating correspondence of interior skeletal points. DATA: Synthetic objects and real world lateral ventricles segmented from MR images. METHODS: Each object's interior is modeled by a skeletal representation called the s-rep, which is a quadrilaterally sampled, folded 2-sided skeletal sheet with spoke vectors proceeding from the sheet to the boundary. The skeleton is divided into three parts: up-side, down-side and fold-curve. The spokes on each part are treated separately and, using spoke interpolation, are shifted along their skeletal parts in each training sample so as to tighten the probability distribution on those spokes' geometric properties while sampling the object interior regularly. As with the surface-based correspondence method of Cates et al., entropy is used to measure both the probability distribution tightness and sampling regularity. The spokes' geometric properties are skeletal position, spoke length and spoke direction. The properties used to measure the regularity are the volumetric subregions bounded by the spokes, their quadrilateral sub-area and edge lengths on the skeletal surface and on the boundary. RESULTS: Evaluation on synthetic and real world lateral ventricles demonstrated improvement in the performance of statistics using the resulting probability distributions, as compared to methods based on boundary models. The evaluation measures used were generalization, specificity, and compactness. CONCLUSIONS: S-rep models with the proposed improved correspondence provide significantly enhanced statistics as compared to standard boundary models.
PURPOSE: Improving the shape statistics of medical image objects by generating correspondence of interior skeletal points. DATA: Synthetic objects and real world lateral ventricles segmented from MR images. METHODS: Each object's interior is modeled by a skeletal representation called the s-rep, which is a quadrilaterally sampled, folded 2-sided skeletal sheet with spoke vectors proceeding from the sheet to the boundary. The skeleton is divided into three parts: up-side, down-side and fold-curve. The spokes on each part are treated separately and, using spoke interpolation, are shifted along their skeletal parts in each training sample so as to tighten the probability distribution on those spokes' geometric properties while sampling the object interior regularly. As with the surface-based correspondence method of Cates et al., entropy is used to measure both the probability distribution tightness and sampling regularity. The spokes' geometric properties are skeletal position, spoke length and spoke direction. The properties used to measure the regularity are the volumetric subregions bounded by the spokes, their quadrilateral sub-area and edge lengths on the skeletal surface and on the boundary. RESULTS: Evaluation on synthetic and real world lateral ventricles demonstrated improvement in the performance of statistics using the resulting probability distributions, as compared to methods based on boundary models. The evaluation measures used were generalization, specificity, and compactness. CONCLUSIONS: S-rep models with the proposed improved correspondence provide significantly enhanced statistics as compared to standard boundary models.
Authors: Stephen M Pizer; P Thomas Fletcher; Sarang Joshi; Andrew Thall; James Z Chen; Yonatan Fridman; Daniel S Fritsch; Graham Gash; John M Glotzer; Michael R Jiroutek; Conglin Lu; Keith E Muller; Gregg Tracton; Paul Yushkevich; Edward L Chaney Journal: Int J Comput Vis Date: 2003-11-01 Impact factor: 7.410
Authors: Beatriz Paniagua; Amanda Lyall; Jean-Baptiste Berger; Clement Vachet; Robert M Hamer; Sandra Woolson; Weili Lin; John Gilmore; Martin Styner Journal: Proc SPIE Int Soc Opt Eng Date: 2013-03-29
Authors: Liyun Tu; Martin Styner; Jared Vicory; Shireen Elhabian; Rui Wang; Junpyo Hong; Beatriz Paniagua; Juan C Prieto; Dan Yang; Ross Whitaker; Stephen M Pizer Journal: IEEE Trans Med Imaging Date: 2017-09-21 Impact factor: 10.048
Authors: Liyun Tu; Dan Yang; Jared Vicory; Xiaohong Zhang; Stephen M Pizer; Martin Styner Journal: IEEE Signal Process Lett Date: 2015-09-03 Impact factor: 3.109
Authors: Junpyo Hong; Jared Vicory; Jörn Schulz; Martin Styner; J S Marron; Stephen M Pizer Journal: Med Image Anal Date: 2016-02-19 Impact factor: 8.545