A Prototype Representation to Approximate White Matter Bundles with Weighted Currents

Pietro Gori (1) , Olivier Colliot (1) , Linda Marrakchi-Kacem (1) , Yulia Worbe (2) , Fabrizio de Vico Fallani (1) , Mario Chavez (1) , Sophie Lecomte (1) , Cyril Poupon (3) , Andreas Hartmann (1, 4) , Nicholas Ayache (5) , Stanley Durrleman (1)

1 ARAMIS - Algorithms, models and methods for images and signals of the human brain = Algorithmes, modèles et méthodes pour les images et les signaux du cerveau humain [ICM Paris]
2 CRICM - Centre de Recherche de l'Institut du Cerveau et de la Moelle épinière
3 LRMN - Laboratoire d'Imagerie et de Spectroscopie
4 ICM - Institut du Cerveau et de la Moëlle Epinière = Brain and Spine Institute
5 ASCLEPIOS - Analysis and Simulation of Biomedical Images

Quantitative and qualitative analysis of white matter fibers resulting from tractography algorithms is made difficult by their huge number. To this end, we propose an \textit{approximation scheme} which gives as result a more concise but at the same time exhaustive representation of a fiber bundle. It is based on a novel computational model for fibers, called \textit{weighted currents}, characterised by a metric that considers both the pathway and the anatomical locations of the endpoints of the fibers. Similarity has therefore a twofold connotation: geometrical and related to the connectivity. The core idea is to use this metric for approximating a fiber bundle with a set of weighted prototypes, chosen among the fibers, which represent ensembles of similar fibers. The weights are related to the number of fibers represented by the prototypes. The algorithm is divided into two steps. First, the main modes of the fiber bundle are detected using a \textit{modularity based clustering} algorithm. Second, a \textit{prototype fiber selection} process is carried on in each cluster separately. This permits to explain the main patterns of the fiber bundle in a fast and accurate way.

Domaines: Imagerie médicale

Pietro Gori, Olivier Colliot, Linda Marrakchi-Kacem, Yulia Worbe, Fabrizio de Vico Fallani, et al.. A Prototype Representation to Approximate White Matter Bundles with Weighted Currents. MICCAI 2014 - 17th International Conference on Medical Image Computing and Computer Assisted Intervention, Sep 2014, Boston, United States. ⟨hal-01010702⟩