ICA Aneurysm

Acom Aneurysm

Non contrast CT brain shows Hyper dense sub arachnoid bleed in basal cisterns.

Non contrast 3D TOF MR Angiogram of Brain shows an Acom aneurysm.

Further reading: 

Imaging-in-sub-arachnoid-hemorrhage

ICA Aneurysm MR Angio

 
Axial T2 and FLAIR images at the level of sella show a solitary ovoid left parasellar well circumscribed lesion with mixed signals, show flow related signals on 3D TOF Noncontrast MR Angiography, as a saccular outpouching from left intra cranial ICA supraclinoid portion is a an Aneurym.
Mixed signals instead of flow void in the outpouching on T2w images may be due to its partial thrombosis.