The role of mesenchyme in the temporal bone is still poorly understood
. A microscopic study of residual mesenchyme was undertaken in tempora
l bones of children from birth to 5 years of age, Residual mesenchyme
was found to be located in the mastoid antrum and epitympanum more oft
en than in the mesotympanum, The amount of mesenchymal tissue remainin
g in the temporal bones decreased with increasing age. Persistence of
mesenchyme in the temporal bone was related to congenital morphologic
ear anomalies and syndromes, There was also an association evident wit
h pulmonary disease, but not with congenital heart defects, Persistent
mesenchyme was also found to be significantly associated with chronic
middle ear inflammation, and in cases of unilateral otitis media the
ear with otitis media had more residual mesenchyme than the non-otitis
media ear.