Small areas of abnormal T2/FLAIR signal are seen at the grey-white matter junction involving the right occipital lobe and both parietal lobes. These are bright on DWI but are not not unequivocally low on ADC.
High sulcal FLAIR signal in the left precentral gyrus correlates to be high density on CT, and is in keeping with acute subarachnoid blood.
No abnormal enhancement on the postcontrast images. No definite abnormality on suboptimal MRA-patient motion-subtle areas of narrowing in M2 and M3 left MCA branches. No MRI findings suspicious for posterior circulation dissection. The dural venous sinuses are patent on MRV.
There is only subtle MRA abnormality, but the parenchymal findings and convexity subarachnoid blood would be in keeping with RCVS if in the appropriate clinical and lab context. PRES or vasculitis can also have this appearance. Further evaluation with DSA would be helpful. No evidence of cerebral venous sinus thrombosis or cerebral aneurysm.