Mesh-based vs. Image-based Statistical Appearance Model of the Human Femur: a Preliminary Comparison Study for the Creation of Finite Element Meshes

Statistical models have been recently introduced in computational orthopaedics to investigate the bone mechanical properties across several populations. A fundamental aspect for the construction of statistical models concerns the establishment of accurate anatomical correspondences among the objects of the training dataset. Various methods have been proposed to solve this problem such as mesh morphing or image registration algorithms. The objective of this study is to compare a mesh-based and an image-based statistical appearance model approaches for the creation of nite element(FE) meshes. A computer tomography (CT) dataset of 157 human left femurs was used for the comparison. For each approach, 30 finite element meshes were generated with the models. The quality of the obtained FE meshes was evaluated in terms of volume, size and shape of the elements. Results showed that the quality of the meshes obtained with the image-based approach was higher than the quality of the mesh-based approach. Future studies are required to evaluate the impact of this finding on the final mechanical simulations.

Improved microsurgical creation of venous pouch arterial bifurcation aneurysms in rabbits

The choice of the experimental aneurysm model is essential for valid embolization-device evaluations. So far, the use of the rabbit venous pouch arterial bifurcation aneurysm model has been limited by demanding microsurgery, low aneurysm patency rates, and high mortality. This study aimed to facilitate microsurgery and to reduce mortality by optimized peri-/postoperative management.

Intravascular ultrasound-guided creation of re-entry sites to improve intermittent claudication in patients with aortic dissection

PURPOSE: To report percutaneous fenestration of aortic dissection flaps to relieve distal ischemia using a novel intravascular ultrasound (IVUS)-guided fenestration device. CASE REPORTS: Two men (47 and 62 years of age) with aortic dissection and intermittent claudication had percutaneous ultrasound-guided fenestration performed under local anesthesia. Using an ipsilateral transfemoral approach, the intimal flap was punctured under real-time IVUS guidance using a needle-catheter combination through which a guidewire was placed across the dissection flap into the false lumen. The fenestration was achieved using balloon catheters of increasing diameter introduced over the guidewire. Stenting of the re-entry was performed in 1 patient to equalize pressure across the dissection membrane in both lumens. The procedures were performed successfully and without complications. In both patients, ankle-brachial indexes improved from 0.76 to 1.07 and from 0.8 to 1.1, respectively. Both patients were without claudication at the 3- and 6-month follow-up examination. CONCLUSION: Percutaneous intravascular ultrasound-guided fenestration and stenting at the level of the iliac artery in aortic dissection patients with claudication is a technically feasible and safe procedure and relieves symptoms.