Ultrasonic study of schwannoma of the oral and maxillofacial region: Comparison of ultrasonograms and pathologic findings

Abstract

Ultrasonographic study of a schwannoma of the oral and maxillofacial region have rarely been reported. Here we report ultrasonographic findings from the nine cases of schwannoma located in that region that we encountered between 1984 and 1995. The tumor was delineated as a hypoechoic mass with a sharply demarcated contour and posterior echo enhancement. Change in the internal echo followed pathologic degenerative changes: cystic change, bleeding, myxomatous change, and hyaline degeneration. The internal echo was in agreement with the description of Antoni type A tissue, showing hemorrhagic and hyaline degeneration in the tumor. The cystic pattern of the ultrasonogram corresponded to cystic change, and hypoechoic area of the ultrasonogram corresponded to Antoni type B tissue and myxomatous change. The internal echo pattern on the ultrasonogram of a schwannoma was found to reflect the pathologic structure of the tumor.