Abstract: Some aspects of the invention may be directed to a system and method of determining an occurrence of inter-vascular occlusion. The method may include: receiving, from a first sensor, a first indication, related to blood flow in a first artery supplying blood to a first hemisphere of a subject's brain; receiving from one of: the first sensor and a second sensor, a second indication related to the blood flow in a second artery supplying blood to a second hemisphere of the subject's brain; comparing the first and second indications; and determining an occurrence of an inter-vascular occlusion based on the comparison.