The complex nasal dermoid.

In a series of 74 nasal dermoids, 45 (61%) were of the simple variety involving skin only. Twenty nine (39%) were of the complex variety with deeper tissue involvement requiring more extensive surgery. Of the 29 complex dermoids, 9 (31%) extended to the cribriform plate region but only 3 (10%) of these had an extradural extension. All of the complex nasal dermoids were adequately managed by a transnasal approach. On these findings a preliminary craniotomy should only be considered in exceptional circumstances.