Fig. 1From: Invasion of the pterygoid plates: an indicator for regional lymph node failure in maxillary sinus cancerAnatomical direction of invasion of the primary lesion. Tumors with posterior (a) and cranial and medial extension (b) in the present study. Orange: anterior side; Red: posterior side; Blue: medial side; Green: lateral side; Purple: cranial side; and Pink: caudal side. + , combined posterior and lateral extensionBack to article page