Flow diversion with Pipeline Embolic Device as treatment of subarachnoid hemorrhage secondary to blister aneurysms: dual-center experience and review of the literature

Abstract

Repair of ruptured BA with PED may be a safe and durable option.

Editorial on a paper entitled “Combined suture and clipping for the reconstruction of a ruptured blister-like aneurysm”

“…However, one concern that has been repeatedly raised by the neurosurgical community is the need for dual antiplatelet therapy in the light of acute subarachnoid hemorrhage. In contrast, a recent case series of ten patients from two prominent endovascular centers suggests that flow diverters can be placed relatively safely for ruptured blister-like aneurysms and that 9/10 aneurysms are immediately occluded with only one flow diverter device [2]. Remarkably, dual administration of aspirin and clopidogrel did not result in relevant bleeding complications during the subacute follow-up phase after subarachnoid hemorrhage.…”

“…If this happens, the parent artery needs to be trapped and a high-flow bypass with either a radial artery graft or saphenous vein to the M2 segment has to be created. The problem with this in real life is that [1] if the internal carotid artery needs to be trapped most surgeons have no idea about the collateralization pattern and respective ischemic tolerance and [2] harvesting the bypass graft at the very moment following aneurysm rupture and establishing two anastomoses takes a considerable amount of time and may result in MCA/ICA strokes. As a consequence, our threshold for a prophylactic bypass preparation is very low and we attempt to have an idea about the ACOM/PCOM crossflows before starting surgery.…”

“…In our practice, direct clipping remains the first choice for treatment. However, even in experienced hands, clipping can be only successfully accomplished in two-thirds of blister-like aneurysms [2]. Before attempting to clip the aneurysm, the lesion should be carefully inspected whether it is suited for direct clip reconstruction.…”

“…Specifically, the authors were lucky for multiple reasons: [1] the aneurysm was located on the anterior wall, which made it easily amenable to placing the sutures without the need for manipulation of the parent artery. A location at the posterior wall would have made this technique almost impossible; [2] the blister-like aneurysm was a type 2 (berry-like) aneurysm, according to the classification of Bojanowski et al [1]. As a consequence, the defect was limited and well defined, and the remaining vessel wall was healthy and strong enough to hold the sutures; [3] finally, the lumen of the parent artery was large enough to tolerate adaptation of the vessel wall with sutures and clips without inducing hemodynamically relevant stenosis.…”

Endovascular treatment of blister aneurysms

“…1,18,24,35,38,40,53 Other authors use the term to describe such aneurysms of both the ICA and basilar artery, 3,7,36,48,52 and some authors include such aneurysms of the middle cerebral artery (MCA), anterior cerebral artery (ACA), vertebral artery (VA), posterior cerebral artery (PCA), and posterior inferior cerebellar artery (PICA). 4,15,31,35,45,46,49 Whether blister aneurysms of the dorsal ICA have the same or different pathogenesis and natural history as similarly shaped aneurysms of nonbranching sites of other cerebral arteries has not been proven.Perhaps due to the rarity of blister aneurysms, the described pathogenesis is not conclusive. Histological examination of blister aneurysms usually reveals a gap in the arterial wall covered by thin, fibrinous tissue, suggesting that the entity is, in fact, a type of pseudoaneurysm ( Figs.…”