Delayed stroke secondary to increasing mass effect after endovascular treatment of a giant aneurysm by parent vessel occlusion

Abstract

A 47-year-old woman, who had lost vision in her left eye because of a giant left supraclinoid internal carotid artery aneurysm, was referred for endovascular treatment. Parent-vessel occlusion was performed to obtain circulatory exclusion of the aneurysm. Eight days after treatment, she became hemiparetic and dysphasic. Repeat angiography showed compression of the left middle cerebral artery by the swelling giant aneurysm. Preventive measures should be taken to avert worsening of mass effect when giant aneurysms become thrombotic.

fig 1.

MR image and angiogram obtained prior to treatment. A, Coronal T1-weighted MR image after gadolinium chelate infusion shows the giant left supraclinoid aneurysm shifting the left MCA (arrowheads). B, Left ICA angiogram (frontal projection) depicts the left giant nonthrombosed supraclinoid aneurysm stretching the left MCA (arrowheads).

fig 2.

Right carotid angiogram (frontal projection), obtained immediately after left ICA occlusion, shows the absence of retrograde filling of the aneurysm and good cross flow via the ACoA. fig 3. Right carotid angiogram (frontal projection, late arterial phase), obtained 8 d after left ICA occlusion, shows that the stretching and shifting of the left MCA had increased (arrowheads). fig 4. Plain CT scan obtained 20 d after endovascular treatment shows a left MCA territory infarct.