A pre-operative CT and non-contrast-enhanced C-arm CT registration framework for trans-catheter aortic valve implantation

•A fully automatic image registration framework for pre-operative CT and non-contrast-enhanced C-arm CT.•Increasing the rigid-body registration success rate by introducing a more robust initial point.•Increasing the deformable registration accuracy by incorporating anatomical and structural information.•Efficient implementation that significantly reduces the processing time.•Tested on more than 20 data sets, both simulated and real data, the proposed method is statistically significantly better than the state-of-the-art methods.

Contrast-enhanced C-arm CT is routinely used for intra-operative guidance during the trans-catheter aortic valve implantation (TAVI); however, the requirement for contrast agent injection is not preferable, especially for patients with renal insufficiencies. To address this problem, we present a novel framework for fully automatic registration of pre-operative CT and non-contrast-enhanced C-arm CT. The proposed framework provides an improved workflow and minimizes the usage of contrast agent in the TAVI procedure. Our framework consists of three steps: coarse rigid-body alignment, anatomical knowledge-based prior deformation field generation, and fine deformable registration. We validated the proposed framework on 20 real patient data sets. Based on the 20 data sets, the mesh-to-mesh errors at the aortic root from different methods are measured. Our proposed method significantly outperforms the other state-of-the-art methods. Specifically, we achieve the registration accuracy at 1.76 ± 0.43 mm which is clinically plausible. Quantitative evaluation on real non-contrast enhanced C-arm CT data sets confirms the applicability in the clinical usage. The proposed heart registration method is generic and hence can be easily applied to other cardiac applications.