MR imaging of blood flows in the cavernous sinus

To evaluate blood flows in the cavernous sinus (CS), seven normal CSs and a postmortem CS were evaluated using T1-weighted spin echo sequences. After the noncontrast study, contrast study with Gd-DTPA was performed in all cases except the postmortem one. In the normal CSs, arterial flows of the intracavernous carotid artery (ICA) were disclosed as no-signal areas in the noncontrast study and were not enhanced with Gd-DTPA. Most venous flows in the CS were seen as low-intensity areas in the noncontrast study and were markedly enhanced with Gd-DTPA. However, these low-intensity areas were heterogeneous in intensity and several were higher and lower in intensity compared with most venous spaces. In the postmortem case, the CS showed homogeneous low intensity due to the stasis of blood flow. It was thought that the heterogeneous appearance of venous spaces in the normal CSs was due to flow-related phenomena. This heterogeneous pattern of signal intensity suggested the distribution of flow velocities. MR demonstrated both arterial and venous flows, and this was facilitated by Gd-DTPA. MR is a promising modality for the demonstration of blood flows in the CS.