CT Angiography and MR Angiography in the Evaluation of Carotid Cavernous Sinus Fistula Prior to Embolization: A Comparison of Techniques

raphy (MRA), and digital subtraction angiography (DSA) in elucidating the size and location of carotid cavernous sinus fistulas (CCFs) before embolization treatment. METHODS: This was a retrospective study of 53 patients with angiographically confirmed CCF. All patients underwent pre- and postcontrast-enhanced CTA and DSA, and 50 patients also underwent MRA. Two neuroradiologists rated detectability of the fistula tract as “good,” “moderate, ” or “poor ” in source images obtained by using each procedure. The 2 test was used to compare the imaging modalities with respect to their ability to detect fistulas. RESULTS: CTA did not differ significantly from DSA (P .155), and both CTA (P .001) and DSA (P .007) performed significantly better than MRA in the population as a whole. Differences in performance among the methods, however, depended upon the segmental loca-tion of the fistula along the internal carotid artery (ICA). CTA and MRA were similar in detection of CCFs in patients with a fistula at segment 3. CTA significantly outperformed MRA in patients with a fistula at segment 4, who accounted for approximately half of the population. CONCLUSIONS: CTA source imaging has proved itself as useful as DSA for detecting CCFs. Of the 2 noninvasive techniques, CTA performed better than MRA in the population as a whol