TRAUMATIC CHIASMAL SYNDROME-ASSOCIATED WITH MIDLINE BASILAR SKULL FRACTURES

We studied two young males who had visual field defects consistent wit h optic chiasmal injury after blunt frontal head trauma. One patient a lso had a unilateral optic neuropathy. Long-term follow-up disclosed c omplete bitemporal hemianopsias in these patients. Both patients had m idline basilar skull fractures that traversed the midclivus through th e sella turcica floor, dorsum sellae, and sphenoid sinus. Magnetic res onance images did not identify intrachiasmal hemorrhage as the cause o f the visual field def ect. We believe this fracture pattern, in conju nction with the magnetic resonance image findings, suggests tearing of the optic chiasm on a microscopic, if not macroscopic, scale as the c ause of the complete bitemporal hemianopsia.