Model 1: An overview of the cavernous sinus anatomy is demonstrated (The instructions for use of this and the other following models are as follows: Please use the full screen function for optimal visualization (by clicking on the arrows on the right lower corner of the model). To move the model in 3D space, use your mouse's left click and drag; to enlarge the object, use the mouse's wheel. The right click and drag function moves the model across the plane.) Please click on the “Select an annotation” link at the bottom of the window and then choose “Show annotations” to expose the annotations on the model. Please use the "Visibility" function to remove or add dura and other structures.