MR and CT Findings in Cavernous Sinus and Tributary Veno-Sinus Thrombosis

Abstract

We demonstrate cavernous sinus thrombosis and tributary veno-sinus thrombosis by high resolution CT and MR. Thin section (2mm) contrast enhanced high resolution CT scans obtained in eight patients with a diagnosis of a cavernous sinus thrombosis were compared to 30 normal controls.In six patients CT scans were compared to 3-D spoiled gradient-recalled acquisition in the steady state (SPGR) sequences. Contrast enhanced CT of the cavernous sinus in eight patients differed from normal controls with respect to the size of filling defects that exceeded 7 mm in 78.6% of patients compared to 9.1% of controls. Thrombus formation accounted for a mean density of 26.7 ± 7.8 HU compared to −1.1 ± 12.3 HU in controls. Expansion of the cavernous sinus due to thrombosis was indicated by a significant increase in diameter (mean 10.8 mm) vs 8.3 mm in controls. Tributary veno-sinus thrombosis affected the superior ophthalmic vein and the inferior petrosal sinus in four patients each and the sphenoparietal sinus in two patients.Thin — section CT and the contrast — enhanced SPGR MR sequences were equally suited to recognize cavernous sinus and tributary veno-sinus thrombosis. High resolution CT and MR findings indicate that tributary veno-sinus thrombosis not only affects the superior ophthalmic vein but may be more common than previously assumed.