Nonsupervised 3D registration of PET and MRI data using chamfer matching

An extension of the chamfer matching technique to accurately register 3-D medical images from different modalities is proposed. A shape-independent surface matching technique yields a rigid body transformation, which allows the transfer of information between modalities. The optimal transformation is inferred from the minimization of a quadratic generalized distance between discrete surfaces. The minimization process is efficiently performed via the precomputation of a 3-D distance map. The entire registration process requires no supervision. The accuracy of the proposed unsupervised 3-D registration method turned out to be very satisfactory for PET (positron emission tomography) medical studies