Orbital color Doppler ultrasound as noninvasive tool in the diagnosis of anterior-draining carotid-cavernous fistula

Purpose To investigate the role of orbital color Doppler ultrasound (OCDUS) in the diagnosis of carotid-cavernous fistula (CCF) with anterior drainage and particularly whether a negative OCDUS could avoid an invasive diagnostic cerebral angiography (DSA). Materials and methods Twenty-two consecutive patients with ophthalmic signs suspecting CCF were submitted to ophthalmologic examination, OCDUS and DSA. CCF diagnosis with OCDUS was based on the finding of a reversed, arterialized and low-resistive-index (RI <0.5) blood flow in the superior ophthalmic vein (SOV). Sensibility, specificity, PPV, NPV, and accuracy of OCDUS were calculated considering both patients and eyes, using DSA as gold standard. Results DSA demonstrated 20 CCFs in 18 patients. Considering the patients, in 18/22 CCF diagnosis was positive at OCDUS and DSA while 4/22 were negative at both. Considering the eyes, in 24/43 CCF diagnosis was positive at both DSA and OCDUS (total eyes = 43, due to one case of SOV thrombosis). In 19/43 eyes diagnosis was negative at both OCDUS and DSA. So sensitivity, specificity, PPV, NPV, and accuracy of OCDUS in the patients and eyes analysis were all 100 %. Conclusions OCDUS is a reliable, noninvasive tool in the diagnosis of CCF; a negative OCDUS could avoid an invasive DSA in patients suspected for anterior-draining CCF.