Direct arteriovenous fistula at the inferolateral trunk mimicking carotid cavernous fistula without involving the cavernous sinus: a case report

The authors present the case of a 66-year-old female who developed progressive pulsating exophthalmos, a bruit, and conjunctival chemosis 7 months after a head injury. These symptoms, though highly suspicious of carotid cavernous fistula, were caused by an arteriovenous fistula (AVF) between the inferolateral trunk (ILT) and the ophthalmic veins. A direct AVF at the branch of the ILT without involvement of the cavernous sinus is extremely rare, but could occur in the case of acquired AVF since the ILT has some branches around venous structures outside the cavernous sinus. The clinical implications of this case are discussed in terms of the anatomical aspects.