Development of a Generic Geometric 3D Model of the Breast Based on Magnetic Resonance Imaging and Clinical Constatations.

Breast geometric models constitute the foundation of biomechanical simulations. Most currently available models rely on patient-specific reconstructions derived from magnetic resonance imaging (MRI) or computed tomography (CT) scans. These approaches present several limitations, including requirement for patient-specific imaging data, need for manual or semi-automatic segmentation of images (both time-consuming and operator-dependent), and limited accuracy in biomechanical simulations due to large tissue deformations. The objective of this study was to develop a generic three-dimensional (3D) geometric breast model that can be easily adapted using only a limited set of morphological parameters, thus eliminating the need for image segmentation. This prospective study was conducted in the Breast Surgery Department of Montpellier University Hospital, France, between March 2022 and March 2025, and consisted of four steps: (1) definition of constitutive materials based on clinical observations; (2) development of geometric model; (3) evaluation of model validity through reproductions of clinical cases; (4) construction of a numerical model. The proposed simplified geometric model was subdivided into five compartments: (1) chest wall; connective tissue, modeled as a cone composed of three compartments: (2) cone base (anchoring ring), (3) the surface enveloping the glandular tissue, and (4) the nipple-areolar complex ring; (5) glandular/adipose tissue volume. This 3D model was able to represent various breast morphologies and conditions. Based on these observations, a numerical 3D geometric model was developed, using a mass-spring system. Further validation of the biomechanical accuracy of the model in simulating breast deformations is still required. This will be addressed in a future study comparing model outputs with breast MRI acquisitions obtained in three different positions. Trial Registration: Clinicaltrials.gov: NCT05301998.