| Geometric and intensity distortions due to the presence of metallic implants in magnetic resonance imaging (MRI) impede the full exploitation of this advanced imaging modality. Acquiring image-pairs of a custom-designed three-dimensional grid phantom with and without the studied metallic implant, inside allowed artifact quantification and identification of suitable image regions for correction. The identified image regions were subsequently aligned using a point-based thin-plate spline image registration algorithm. The calculated transformation functions utilized to align image content in grid image-pairs described the implant distortions and could therefore be used to correct any other images containing the same distortions. The results demonstrate successful correction of grid phantom images with a metallic implant. Furthermore, the calculated correction was applied to porcine thigh images bearing the same metallic implant, simulating a patient environment. Qualitative and quantitative assessments of the proposed correction method are included. |
