Embolus Transport and Distribution in the Brain in the Presence of Contralateral Carotid Occlusion*

Embolic Stroke of Undetermined Source comprises a significant amount of all ischemic strokes with the current ability to identify etiology being limited. Identifying stroke etiology is a vital factor in treatment efficacy and reducing recurrent events. The carotid arteries provide a critical location where bilateral buildup of atherosclerotic plaque can embolize and move into the cerebral arteries. Diseased carotids are suspect to Contralateral Carotid Occlusion (CCO) where one carotid artery is fully occluded and the other is partially occluded. The common understanding of carotid embolization is that stroke events are mainly limited to the ipsilateral hemisphere respective to the carotid artery. Contralateral transport can lead to possible confusion on the proper etiology from which a stroke originated thus leading to a decrease in treatment efficacy. We investigate how non-intuitive embolus transport from carotid and cardiogenic sources may occur in the presence of CCO. Using an in silico methodology, we developed a patient-specific hemodynamics and embolus transport model within the heart-to-brain pathway to conduct an investigation on how cardiogenic and carotid sourced embolization may complete non-intuitive embolus distribution in the form of contralateral movement.