Background: The image registration using positron emission tomography (PET) and
magnetic resonance imaging (MRI) has been studied extensively. The purpose of this
project is to propose a patient-specific image registration model that can improve both
the accuracy and efficiency of the registration process. Large-scale deformation of the
breast makes image registration of the breast a challenging task. Usually, a patient
undergoes MRI in the prone position and PET in the supine position. Registration of
breast in supine position with breast in prone position is a challenge.
Methods: Eight cases with corresponding pairs of PET/computed tomography (CT)
and MRI breast images were used in this study for the performance of PET/MRI
registration. Registration was based on a biomechanical finite element model that could
simulate large-scale deformation of the breast under pressure.
Results: In this study, an accurate patient-specific registration model was built with a
target registration error (TRE) of 4.77±2.20 mm.
Conclusion: Image deformation due to the effect of gravity was successfully modeled
by the finite element method.
Keywords: Finite Element Analysis, Breast Modeling, PET and MR Registration.
