Atlas-Based 3D Intensity Volume Reconstruction from 2D Long Leg Standing X-Rays: Application to Hard and Soft Tissues...

In this chapter, the reconstruction of 3D intensity volumes of femur, tibia, and three muscles around the thigh region from a pair of calibrated X-ray images is addressed. We present an atlas-based 2D-3D intensity volume reconstruction approach by combining a 2D-2D nonrigid registration-based 3D landmark reconstruction procedure with an adaptive regularization step. More specifically, an atlas derived from the CT acquisition of a healthy lower extremity, together with the input calibrated X-ray images, is used to reconstruct those musculoskeletal structures. To avoid the potential penetration of the reconstructed femoral and tibial volumes that might be caused by reconstruction error, we come up with an articulated 2D-3D reconstruction strategy, which can effectively preserve knee joint structure. Another contribution from our work is the application of the proposed 2D-3D reconstruction pipeline to derive the patient-specific volumes of three thigh muscles around the thigh region.