There is an ovoid mass within the sella and left cavernous sinus. The mass is closely related to the left cavernous internal carotid artery but does not appear to be causing arterial stenosis. Within the mass there are prominent flow voids. No solid component. The pituitary and infundibulum are displaced towards the right. No diffusion restriction seen.
Conclusion: Left sellar/suprasellar mass almost certainly represents an ICA aneurysm arising from the left cavernous ICA.