FIG 1. 41-year-old woman with sudden onset of neck pain and stiffness, and a sensation of blood rushing in her ears.

A, Right internal carotid arteriogram, lateral view, late arterial phase, shows a large, direct carotid-cavernous fistula with rapid filling of the right cavernous, superior, and inferior petrosal sinuses and numerous pial cerebral veins (arrows).

B, Right common carotid arteriogram, lateral view, after embolization shows the fistula has been closed by one detachable latex balloon (arrow) with restoration of normal arterial blood flow.

C, Gross dissection of the base of the skull and right cavernous sinus with posterior clinoid processes removed and left cavernous sinus exposed. Note the right optic nerve (asterisk). The proximal balloon tip is visible through the carotid defect (arrow).

D, Right cavernous carotid artery with balloon in situ (arrow on carotid defect rim). Note the proximal petrous internal carotid artery (P) and the distal supraclinoid internal carotid artery (D).

E, With balloon removed, the vessel defect can be seen (arrow on carotid defect rim). Note the petrous (P) and supraclinoid (D) segments of the internal carotid artery. Also note that the proximal, valve end of the balloon protrudes through the defect and the distal end protrudes into the parent internal carotid artery.