An experimental and computational study of blunt carotid artery injury.

A carotid artery dissection begins as a tear or defect of the intimal lining of the artery, and can lead to luminal occlusion and ultimately cerebral ischemia. Our aim is to conduct an organ level validation of a finite element model of the carotid artery using an experiment designed to elicit internal layer failure within fluid-filled carotid artery samples. A 2.4-kg beveled guillotine is dropped from three heights (0.3, 0.5 and 0.7 m) onto fluid-filled porcine carotid arteries and resulting damage is recorded. These events are modeled using finite element analysis. Stress, strain and strain rate are correlated to experimental outcome. Internal layer damage is reported in half of the experiments, with damage occurring with 100% frequency at a drop height of 0.7 m. Simulations of this experiment result in maximum principal stress and strain values of 1.43 MPa and 46.2% respectively. The strain level predicted by the model for this impact scenario approaches the strain to intimal failure level for porcine arteries found in the literature. The results of this study represent an important step in validating this finite element carotid artery model at the organ level.