Direct and Dural Carotid Cavernous Sinus Fistulas: Comparison of Clinical Characteristics.

Purpose: To compare the clinical characteristics of patients with direct and dural carotid cavernous sinus fistulas (CCFs).

Methods: The medical records of 60 patients diagnosed with CCFs were retrospectively reviewed. The collected data included demographic characteristics, clinical findings, and ocular manifestation. The clinical characteristics of the direct and the dural CCFs were compared on head-to-head basis. Logistic regression analysis was used to demonstrate the direction and magnitude of the difference and reported as odds ratio with its 95% confidence interval.

Results: There were 28 patients (46.67%) with direct CCFs, and 32 patients (53.33%) with dural CCFs. Patients with direct CCF were mostly male (p=0.023), younger age (p<0.001), had history of trauma (p<0.001), and more visual impairment at presentation (p=0.025), when compared to those with dural CCFs. In addition, patients with direct CCF had significantly more chemosis (p=0.005), proptosis (p=0.042), bruit (p<0.001) and dilated retinal vessels (p=0.008) than those with dural CCF. Thirty patients (50%) had increased intraocular pressure (IOP). Mean IOP of the affected eyes was significantly higher than the unaffected eyes (p<0.0001). In patients with normal IOP, mean IOP of the affected eyes was also higher than the unaffected eyes (p=0.0027).

Conclusion: Patients with direct CCF were younger age, associated with trauma, and more visual impairment at presentation. Chemosis, proptosis, bruit and dilated retinal vessels were detected more in the direct CCF than the dural CCF. Despite normal IOP, affected eyes had significantly higher IOP than the unaffected eyes. Information on these clinical characteristics may be helpful in discrimination of the direct type, which is more urgent for further investigation and treatment.