Philippe Demaerel
In an emergency setting we almost daily get a request to exclude venous sinus thrombosis. The clinical presentation is often misleading.
MR imaging obviously has advantages (e.g., it does not require radiation and has higher temporal and spatial resolutions), but it cannot always be obtained during the night or over the weekend. CT is almost always available and close to the emergency department.
Unenhanced brain CT is easier to obtain and faster than a contrast-enhanced CT. Therefore, excluding or confirming an acute venous sinus thrombosis by means of an unenhanced brain CT would result in global benefits, certainly in those areas in the Third World or Global South where contrast agents are not routinely available.
The paper by Black et al1 on the relationship between hematocrit and Hounsfield units in venous sinuses drew our attention. We decided to investigate the sensitivity of unenhanced brain CT when measuring the density of the venous sinus to detect acute venous sinus thrombosis.
Since the publication of our paper, we have received positive feedback from both radiologists and neurologists. They now increasingly accept unenhanced CT, while in the past, they typically wanted contrast-enhanced CT to be administered. Research in this field is ongoing and relevant because of the frequently encountered radiologic request for exclusion of venous thrombosis. Our observations were confirmed in a larger multicentric study.2
In the recent literature, there have been reports on the use of CT perfusion imaging in assessing possible venous sinus thrombosis, but the importance of our findings lies in their demonstration that the most simple examination in neuroradiology, unenhanced brain CT, can produce the very important diagnosis of acute venous sinus thrombosis without the need of MR imaging, CT/MR venography, or perfusion imaging.