The value of long-term angiographic follow-up following Pipeline embolization of intracranial aneurysms

Abstract

BackgroundFlow diversion of intracranial aneurysms with the Pipeline Embolization Device (PED) is commonly performed, but the value of long-term angiographic follow-up has not been rigorously evaluated. Here we examine the prevalence of actionable findings of aneurysm recurrence and development of in-stent stenosis in a cohort of patients that underwent long-term angiographic follow-up at multiple time points.MethodsAngiographic data from eligible patients were retrospectively assessed for aneurysm occlusion, in-stent stenosis, and aneurysm regrowth or recurrence. Patients were included in this study if they underwent angiographic imaging at 6 months post-treatment and at least one later time point.Results100% (132/132) of aneurysms occluded at 6 months remained occluded at final follow-up. 85.7% (6/7), 56.3% (27/48), and 25% (6/24) of aneurysms with entry remnant, subtotal filling, and total filling, respectively, at 6 months were completely occluded at final follow-up. 98.7% (147/149) of PED constructs that demonstrated no stenosis at 6 months demonstrated no stenosis at final angiography, while 44.4% (8/18) of PED constructs demonstrating in-stent stenosis at 6 months had resolution of stenosis on final angiography.ConclusionsAmong patients who undergo treatment of intracranial aneurysms with PED, the value of long-term angiography in patients demonstrating complete aneurysm occlusion and no in-stent stenosis on 6 month post-treatment angiography is low.

In-Stent Stenosis After Pipeline Embolization Device in Intracranial Aneurysms: Incidence, Predictors, and Clinical Outcomes

“…6 Furthermore, many studies demonstrating initial ISS have found that ISS was improved or resolved at later imaging followup, especially asymptomatic and mild ISS. 15,[20][21][22] Based on a retrospective study of 94 patients treated with PED, 52 patients (55.3%) had varying degrees of ISS at the initial follow-up. After secondary follow-up, 94.1% (16/17) of these patients showed partial improvement or stable in ISS.…”

Retreatment of previously flow diverted intracranial aneurysms with the pipeline embolization device

“…Aneurysm occlusion following treatment with PED demonstrates high durability, and therefore the rate of recurrence after occlusion is exceedingly low. 12 However, aneurysms remnants after flow diversion are not uncommon. 21 While the long-term rupture risk of these remnants is not well understood and may differ from untreated aneurysms, retreatment may be necessary to reduce risk of later hemorrhage.…”

“…5,6 Retreatment of brain aneurysms that were previously treated but inadequately occluded has been important to mitigate long-term risk of rupture, particularly in the context of recurrence after endovascular coiling. [7][8][9][10]11 Incomplete aneurysm occlusion can also occur after flow diversion, but due to the very low rate of aneurysm recurrence after complete occlusion, 12 most cases involve residual aneurysm remnants. The origin of these remnants may be related to technical factors or the endothelialization process of flow-diverted aneurysms, but how to treat these remnants is not completely understood.…”

A review of technological innovations leading to modern endovascular brain aneurysm treatment

“…At times, this may require placement of two or three additional devices through the first to achieve adequate flow diversion and scaffolding for the endothelium. As a consequence of this process, recurrence after angiographic cure of a flow diverted aneurysm is exceedingly rare ( 101 ). More broadly, the arrival of flow diversion removed the need to enter the aneurysm itself during treatment, obviating the inherent risks of these maneuvers.…”

“…Flow diverting stents proved to be versatile devices and are capable of reaching durable aneurysm cure by promoting healing of the diseased parent vessel ( 101 , 103 ). Drawbacks to flow diversion including the need for DAPT to minimize thromboembolic complications, as well as relatively poor efficacy when employed to treat wide-neck bifurcation aneurysms compared to side-wall aneurysms ( 104 ).…”