IV.A.3 Head & Back: Dura Page 3 of 5

+	Step 19:   (Rotate and) add the internal and common carotid arteries.
	Step 20:  Compare the illustration to the cadaver, and use the Draw tool to identify the major arterial supply. Notice that the internal carotid artery makes a "step-like" pattern as it passes through the sphenoid bone and the cavernous sinus. The external carotid arteries will be added when we discuss the arterial supply to the face and scalp.