“…First, the layer that leaves the adventitia under direct vision is found, and peeling along this layer is performed in the same manner as in endarterectomy under direct view. 11–13) Therefore, in the case of calcification in which the layer structure of the blood vessel wall is destroyed and forms into a mass, it is difficult to identify the peeling layer; hence, endarterectomy becomes difficult to perform. Sometimes, endarterectomy is not performed at all.…”