Direct carotid-cavernous fistulas occurring during neurointerventional procedures

This study shows the frequency and types of carotid-cavernous fistula (CCF) complications that occurred during endovascular treatment. Transarterial endovascular surgeries involving the anterior circulation were performed for 1071 cases at our hospitals during four years. CCFs occurred in nine of 1071 cases (0.8%). CCF risk factors were female sex (p=0.032), aneurysmal location in the paraclinoid portion (p<0.001), and use of a distal access catheter (DAC) (p<0.001). There were no significant correlations between CCF risk and procedure type (p=0.411-1.0) and balloon use or nonuse (p=0.492). Eighty-nine percent (eight of nine) of the CCFs occurred at the genu of a cavernous internal carotid artery (ICA). Two cases of CCF disappeared spontaneously. The shunt was decreased by balloon expansion in one case, no additional treatment was required in one case, and five cases required transarterial fistula coil embolization. It is necessary to remember that a CCF may occur especially in aneurysmal treatment using a DAC in a female patient. The DAC and the 0.035-inch guidewire should be kept proximal to the carotid siphon and not go beyond it. When we cannot avoid navigating beyond it, we should consider using a softer DAC. In the case of a CCF caused by a DAC, it may be cured spontaneously or is treatable by transarterial coil embolization.