Click on image to view larger version.
Fig 4. The only false-negative CTA, in a 72-year-old man with severe headache, lacking hemorrhage on CT. However, the symptoms prompted an MR imaging/MR angiography (data not shown), with tiny infarcts and a questionable left supraclinoid ICA outpouching. Thereafter, the patient underwent catheter DSA to exclude vasculitis (which was negative), which showed a 2-mm periophthalmic aneurysm on 3DRA (dashed arrow, A). Closer, repeat review of the CTA showed the lesion projecting medially over the bony sella (arrow, B).
