Gas in the cavernous sinus.

PURPOSE To evaluate the significance of cavernous sinus gas identified on head CT scans. METHODS Head CT scans were viewed prospectively for a period of 3 years. The charts of patients who demonstrated cavernous sinus gas were reviewed. RESULTS Seventeen patients without head trauma and 10 patients with head trauma demonstrated gas in the cavernous sinus. None of the patients had symptoms or developed symptoms originating in the cavernous sinus. All of the patients without trauma had an intravenous line in place. Sphenoid fractures or basilar skull fractures were not a constant finding in trauma patients with cavernous sinus gas. CONCLUSIONS In patients without symptoms referable to the cavernous sinus, gas in the cavernous sinus does not appear to be a significant finding. The gas is most likely the result of venous air emboli from intravenous lines or penetrating trauma.