Figure 2: The coronal images above, showing unilaterally traced canals of three different subjects, were selected as examples of the most common canal pathways observed in the medial-lateral plane. The images also demonstrate how the canal paths and lengths were determined; the most straight-line path in the center of the canal, superiorly from the midpoint of the pterygoid canal entrance into the pterygopalatine fossa to the inferior surface of the horizontal hard palate. In some cases, bilateral canals could be traced in the same sagittal slice if both appeared patent (c), but in most cases only one patent canal was visible in a single slice and navigation anterior or posterior was required to see the other. Most common canal pathways demonstrated in the images are (a) canal travels directly inferior from fossa, (b) canal travels inferior-lateral for a distance then directly inferior for the remainder, and (c) canal travels inferior-lateral for a distance then inferior-medial for the remainder.