PT  - JOURNAL ARTICLE
AU  - Abdol Aziz Ould Ismail
AU  - Drew Parker
AU  - Moises Hernandez-Fernandez
AU  - Ronald Wolf
AU  - Steven Brem
AU  - Simon Alexander
AU  - Wes Hodges
AU  - Ofer Pasternak
AU  - Emmanuel Caruyer
AU  - Ragini Verma
TI  - Freewater EstimatoR using iNtErpolated iniTialization (FERNET): Toward Accurate Estimation of Free Water in Peritumoral Region Using Single-Shell Diffusion MRI Data
AID  - 10.1101/796615
DP  - 2019 Jan 01
TA  - bioRxiv
PG  - 796615
4099  - http://biorxiv.org/content/early/2019/10/08/796615.short
4100  - http://biorxiv.org/content/early/2019/10/08/796615.full
AB  - Characterization of healthy versus pathological tissue is a key concern when modeling tissue microstructure in the peritumoral area, confounded by the presence of free water (e.g., edema). Most methods that model tissue microstructure are either based on advanced acquisition schemes not readily available in the clinic, or are not designed to address the challenge of edema. This underscores the need for a robust free water elimination (FWE) method that estimates free water in pathological tissue but can be used with clinically prevalent single-shell diffusion tensor imaging data. FWE in single-shell data requires the fitting of a bi-compartment model, which is an ill-posed problem. Its solution requires optimization, which relies on an initialization step. We propose a novel initialization approach for FWE, FERNET, which improves the estimation of free water in edematous and infiltrated peritumoral regions, using single-shell diffusion MRI data. The method has been extensively investigated on simulated data and healthy and brain tumor datasets, demonstrating its applicability on clinically acquired data. Additionally, it has been applied to data from brain tumor patients to demonstrate the improvement in tractography in the peritumoral region.