An young woman from an undeprivileged country had sudden onset severe headache followed by repeated vomitings, transient loss of consciousness. A CT head was done… unfortunately a contrast study… which showed a rounded contrast filled structure in left ambient cistern.

An MRI was subsequently performed after 2 days which showed hyperintensity in the left medial temporal lobe. An MRA showed poor visualisation of left PCA and was otherwise unremarkable.

She was put on antitubercular drugs!

She then landed up with us. A diagnosis of aneurysm was made and an DSA done.

the aneurysm had disappeared. There was cutoff of the left PCA after the ambient segment. Retrograde filling of the entire left PCA territory was however noted via collaterals from left MCA.

She was now asymptomatic and was sent back home with the advice of a follow up angiogram after 3 months.

PCA dissecting aneurysms are a distinct form of vascular lesions, usually occurring at the P2 segment and have variable clinical presentation.

They have however relatively good outcome as compared to other intracranial aneurysms.

Many of then undergo spontaneous healing, as in our patient (although the PCA had got occluded too), and it is not a bad idea to just observe them.

However, with the advent of modern endovascular techniques, coiling is a feasible option.

Coiling however usually means sacrificing the artery with variable resulting deficits (usually not disabling).

MCA to PCA collateral flow most of the times is able to perfuse the PCA territory adequately, however the patient must be told of deficits, chiefly vision problems.