Endovascular Treatment of Middle Cerebral Artery Aneurysms with Flow Modification with the Use of the Pipeline Embolization Device

Abstract

BACKGROUND AND PURPOSE:The Pipeline Embolization Device was reported to be safe and effective in the treatment of sidewall aneurysms, preserving the patency of the vessels covered by the construct. However, to date, the safety and efficacy of this device in treating bifurcation aneurysms remains unknown. We report our preliminary experience with the use of the Pipeline Embolization Device in the management of MCA aneurysms located at the bifurcations, including mid-and long-term follow-up data.

Flow-Diverter Stents for the Treatment of Saccular Middle Cerebral Artery Bifurcation Aneurysms

“…The aneurysms treated with this technique were very challenging, and though anatomic results were superior in other FDS studies (80%-92%), [28][29][30] better results could be achieved with other techniques.…”

“…Very recently, some articles investigating their use in the treatment of MCA aneurysms were published, though study populations were sometimes heterogeneous and included saccular and fusiform aneurysms and both bifurcation and nonbifurcation types. 28 reported good results, with 84% complete occlusion at follow-up. Although the last follow-up showed that 43% of covered branches had reduced caliber or were occluded, no permanent neurologic deficits occurred.…”

Small Pipes: Preliminary Experience with 3-mm or Smaller Pipeline Flow-Diverting Stents for Aneurysm Repair prior to Regulatory Approval

“…Most larger flow-diversion series either did not report any cases of devices of Յ3 mm, or they did not include documentation of the parent vessel or device size. 4,[6][7][8] Our current series of 12 patients demonstrated that the use of these small devices is technically feasible and safe, with excellent clinical and radiologic outcomes at a median latest follow-up of 1.5 years. The rates of occlusion (75%) and near-or complete occlusion (92%) are similar to overall data published for flow-diversion treatment (76% complete occlusion at 1 year), 9 and our current series comprises 50% posterior circulation aneu- rysms, which are known to carry higher rates of complications.…”

“…Pistocchi et al 1 reported a series of 26 patients, most of whom were treated with flow-diversion devices of Յ3 mm, with good outcomes including an occlusion rate of 83% and a neurologic complication rate of 4% with no hemorrhage. Yavuz et al 4 recently reported 25 cases of MCA aneurysms located at the bifurcation or more distally, with an occlusion rate of 84% and only 1 case of long-term neurologic impairment, which was mild (mRS 1). Presumably, many of the cases in this series involved small-diameter parent vessels and PEDs, but these specific data were not reported.…”

“…This topic has been widely discussed in the flow-diversion literature, with the consensus suggesting that branch occlusions are not uncommon but are often clinically silent. 5,11,12 It remains unclear whether small-diameter flow diverters have a greater propensity to cause occlusion or symptomatic flow reduction to covered arterial branches, but the series by Yavuz et al 4 showed relatively high rates of branch occlusion (3/21, 14%) and a reduced caliber of the covered branch (6/21, 29%) among 21 MCA bifurcation aneurysms treated. 12 Our series demonstrated 1 case (8%) of a jailed branch artery occlusion (frontopolar artery) with an associated area of diffusion restriction on MR imaging (postprocedure day 1) suggestive of infarct, but this was clinically silent.…”