Tailored flow sequestration treatment using high-flow and low-flow bypass for partially thrombosed giant internal carotid artery aneurysm—a technical case report

Abstract

Direct clipping of giant partially thrombosed intracranial internal carotid artery (ICA) aneurysms is challenging, especially when important perforating arteries are involved. Proximal occlusion with bypass represents a possible alternative approach. An 80-year-old female presented with worsening visual acuity and severe headache caused by partially thrombosed giant (38 mm in diameter) aneurysms of the right ICA, suggestive of impending rupture. Direct clipping in conjunction with temporary occlusion of the lesion involving the anterior choroidal artery (AChA) was considered too risky. Thus, we sequestrated the ipsilateral ICA flow into a low-flow and a high-flow system using two external carotid artery (ECA)-ICA bypasses and one in situ bypass with cervical ICA ligation. As a result, the low-flow system by the superficial temporal artery-middle cerebral artery (MCA) bypass perfused mainly the proximal MCA lesions and aneurysm, whereas the high-flow system by ECA-radial artery-M2 bypass exclusively supplied the residual distal MCA area. This tailored flow sequestration successfully interrupted intra-aneurysmal flow and accelerated near-complete thrombosis of the aneurysm while preserving the AChA and avoiding any significant neurological deterioration. We conclude that this method is effective for the management of giant partially thrombosed aneurysms of the ICA, especially when direct clipping is difficult.

Flow alteration therapy for impending rupture of intracranial giant aneurysm after flow diverter placement

“…With this, we sought to reverse and minimize blood flow of the ICA while avoiding ischemic complications. [ 7 , 13 ] Although being unintentionally combined, reverse, and minimal flow created by flow alteration may have synergized with the flow diversion effect by the preexisting FD to suppress aneurysmal growth and rupture. We selected the supraclinoid ICA just proximal to the PCoA as the obliteration site.…”

“…Thus, we were able to minimize the retrograde ICA blood flow by choosing the tiny PCoA as an outflow conduit of the flow alteration strategy, rather than choosing the larger ophthalmic artery. [ 5 , 7 ] PCoA preservation also contributed to avoiding blind alley formation for the retrograde flow at the distal end of the coil mass, which may cause delayed AchA thrombosis. [ 9 , 10 ] Even though sufficient blood flow is provided through the extracranial-intracranial bypass, endovascular supraclinoid ICA obliteration is associated with ischemic complications, presumably because of distal coil migration to the AchA and PCoA.…”

Middle cerebral artery dissection causing subarachnoid hemorrhage and cerebral infarction: Trapping with high-flow bypass preserving the lenticulostriate artery

“…Reconstructive methods aiming to maintain the parent artery are not suitable for these needs, whereas deconstructive trapping of the dissecting lesion might be the best option. Third, the appropriate flow out design would be critical to maintain blood flow and to avoid late thrombosis in the nearby important perforator, the LSA,[ 3 11 17 ] as well as ensure adequate perfusion of the vast distal vascular beds of the MCA.…”