Walsh & Hoyt: Prognosis after Treatment

After attempted occlusion of a direct CCF using one or more detachable balloons or platinum coils, closure of the fistula should be verified by either intraoperative or postoperative angiography. The ocular pulse amplitudes of the two eyes can also be compared using a pneumotonometer. Equalization of ocular pulse amplitudes or reduction of the ocular pulse amplitude on the side of the fistula below that of the opposite side suggests that the fistula has been closed successfully; however, normalization of the ocular pulse amplitudes could also occur if the fistula were still open but no longer draining anteriorly. In such a case, the fistula might be filling superficial cerebral veins, and the patient might be at risk for experiencing a potentialy life-threatening intracranial hemorrhage. Thus, we believe that all patients who undergo attempted occlusion of a direct CCF should have post-treatment cerebral angiography. When angiography indicates complete closure of the fistula with preservation of patency of the internal carotid artery, the fistula usually does not reopen.