Apr 22, 2015

MIDA: A Multimodal Imaging-Based Detailed Anatomical Model of the Human Head and Neck

Maria Iacono, Esra Neufeld, Esther Akinnagbe, Kelsey Bower, Johanna Wolf, Ioannis Oikonomidis, Deepika Sharma, Bryn Lloyd, Bertram Wilm, Michael Wyss, Klaas Pruessmann, Andras Jakab, Nikos Makris, Ethan Cohen, Niels Kuster, Wolfgang Kainz, and Leonardo Angelone, PLoS ONE, Volume 10, Issue 4, online April 22, 2015

Computational modelling and simulations are increasingly being used to complement experimental testing for analysis of safety and efficacy of medical devices. We have developed a multimodal imaging-based detailed anatomical model of the human head and neck. The model was obtained by integrating three different magnetic resonance imaging (MRI) modalities, the parameters of which were tailored to enhance the signals of specific tissues: i) structural T1- and T2-weighted MRIs; a specific heavily T2-weighted MRI slab with high nerve contrast optimized to enhance the structures of the ear and eye; ii) magnetic resonance angiography (MRA) data to image the vasculature, and iii) diffusion tensor imaging (DTI) to obtain information on anisotropy and fibre orientation. The unique multimodal high-resolution approach allowed resolving 150 structures, including several distinct muscles, bones and skull layers, arteries and veins, as well as salivary glands. The model offers also a detailed characterization of eyes, ears, and deep brain structures. A special automatic atlas-based segmentation procedure was adopted to include a detailed map of the nuclei of the thalamus and midbrain into the head model. The suitability of the model to simulations involving different numerical methods, discretization approaches, as well as DTI-based tensorial electrical conductivity, was examined in a case-study, in which transcranial alternating current stimulation was modelled.

The scientific and technical impact of the study can be summarized as:

  • Creating and making available a detailed, high-resolution head model distinguishing a large number of tissues
  • Creating high element-quality, topologically conforming, non-intersecting surfaces suitable for structured and unstructured discretization techniques
  • Integrating image-based information to inform on inhomogeneous and anisotropic property distributions
  • Demonstrating the suitability of the head model for a large range of numerical simulation techniques