Pipeline Embolization Device Placement Research Articles

Patency of the anterior choroidal artery after flow-diversion treatment of internal carotid artery aneurysms.

Treatment of cerebral aneurysms with flow diverters often mandates placement of the device across the ostia of major branches of the internal carotid artery. We determined the patency rates of the anterior choroidal artery after placement of flow-diversion devices across its ostium. We analyzed a consecutive series of patients in whom a Pipeline Embolization Device was placed across the ostium of an angiographically visible anterior choroidal artery while treating the target aneurysm. Patency of the anterior choroidal artery after Pipeline Embolization Device placement was determined at immediate postoperative and follow-up angiography. Data on pretreatment aneurysm rupture status, concomitant coiling, number of Pipeline Embolization Devices used, neurologic status at follow-up, and follow-up MR imaging/CT findings were collected. Fifteen patients with 15 treated aneurysms were included in this study. In the immediate postprocedural setting, the anterior choroidal artery was patent on posttreatment angiography for all 15 patients. Of the 14 patients with follow-up angiography at least 6 months after Pipeline Embolization Device placement, 1 (7%) had occlusion of the anterior choroidal artery and 14 had a patent anterior choroidal artery (93%). No patients had new neurologic symptoms or stroke related to anterior choroidal artery occlusion at follow-up. Of the 9 patients with follow-up CT or MR imaging, none had infarction in the vascular territory of the anterior choroidal artery. In this small study, placement of a Pipeline Embolization Device across the anterior choroidal artery ostium resulted in occlusion of the artery in only 1 patient. It was not associated with ischemic changes in the distribution of the anterior choroidal artery in any patient.

Use of coils in conjunction with the pipeline embolization device for treatment of intracranial aneurysms.

Coiling in conjunction with Pipeline embolization device (PED) placement could provide immediate dome protection and an intraaneurysmal scaffold to prevent device prolapse for intracranial aneurysms with high rupture risk and complex anatomy. To report results after treatment of aneurysms with PED with coils (PED+coils group) or without (PED-only group) at a single-institution. In this case-controlled study, records of patients who underwent PED treatment between 2011 and 2013 were retrospectively reviewed. Twenty-nine patients were treated with PED+coils and 75 with PED-only. No statistically significant between-group differences were found in terms of age, sex, aneurysm location, medical comorbidities, and length of follow-up. Aneurysms treated by PED+coils were larger (16.3 mm vs 12.4 mm, P=.02) and more likely to be ruptured (20.7% vs 1.3%, P=.001) or dissecting (34.5% vs 9.3%, P=.002). PED deployment was successful in all cases. At the latest follow-up (mean, 7.8 months), complete aneurysm occlusion was achieved in a higher proportion of the PED+coils group (93.1% vs 74.7%, P=.03). Device foreshortening/migration occurred in 4 patients in the PED-only group and none in the PED+coils group. Fewer patients required retreatment in the PED+coils group (3.4% vs 16.0%, P=.71). Rates of neurological complications (10.3% PED+coils vs 8.0% PED-only, P=.7) and favorable outcome (modified Rankin Scale score=0-2; 93.1% PED+coils vs 94.7% PED-only, P=.6) were similar. PED+coils may be a safe and effective treatment for aneurysms with high risk of rupture (or rerupture) and complex anatomy. Coiling in conjunction with PED placement provided a higher aneurysm occlusion rate and reduced the need for retreatment.

P-013 Predicting Mass Effect Exacerbation after Pipeline Embolization of Intracranial Aneurysms

IntroductionIn this study, we investigated the clinical and procedural predictors associated with interval growth manifested as new or worsened mass effect after Pipeline Embolization Device (PED) placement for treatment of...

Patency of the posterior communicating artery after flow diversion treatment of internal carotid artery aneurysms

Background and purposeCerebral aneurysm treatment with the Pipeline Embolization Device (PED) often mandates device placement across the ostia of arteries of the Circle of Willis. We determined the patency rates of the posterior communicating artery (Pcomm) after placement across its ostium a PED and studied neurologic outcomes in these patients. MethodsWe analyzed, retrospectively, a consecutive series of patients in whom a PED was placed across the ostium of Pcomm while treating the target aneurysm. Pcomm arterial flow after PED placement was graded on a 3-point scale at post-operative angiography and follow-up angiography. Data on pretreatment aneurysm rupture status, concomitant coiling, number of PEDs used, and neurologic status at follow-up were collected. ResultsEleven patients with 13 aneurysms were included in this study. All patients had an ipsilateral posterior cerebral artery arising from the basilar artery (P1). In the immediate post-procedural setting, four patients (36%) had diminished Pcomm flow rates. After a mean follow-up of 12.6±6.7 months, three Pcomm arteries (27%) were occluded and two Pcomm arteries (18%) had diminished flow. Of patients with diminished flow/occluded Pcomm at follow-up, 80% (4/5) had diminished flow at initial post-procedure angiography compared to none of the six patients without diminished/occluded flow immediately post treatment. No patients suffered new neurologic symptoms at follow-up. ConclusionsApproximately one half of Pcomm arteries demonstrated occlusion or decreased flow at follow-up if the ostia are covered with a flow diversion device. Covering the Pcomm ostium in patients with a P1 did not result in any neurologic deficits.

Pipeline Embolization Device as primary treatment for blister aneurysms and iatrogenic pseudoaneurysms of the internal carotid artery

BackgroundBlood blister type aneurysms (BBAs) and pseudoaneurysms create a unique treatment challenge. Despite many advances in open surgical and endovascular techniques, this subset of patients retains relatively high rates of...

Thromboembolic complications with Pipeline Embolization Device placement: impact of procedure time, number of stents and pre-procedure P2Y12 reaction unit (PRU) value

BackgroundThromboembolic events after Pipeline Embolization Device (PED) placement remain a feared complication among neuroendovascular surgeons. This study aimed to investigate potential risk factors for thromboembolic events in patients undergoing PED...

Flow diversion for complex middle cerebral artery aneurysms

This study aims to evaluate the safety and efficacy of flow diversion for treatment of large and complex middle cerebral artery (MCA) aneurysms. We conducted a retrospective review of the clinical charts of all patients who underwent Pipeline Embolization Device (PED) placement for aneurysm at our institution from October 2010 to October 2013. We included ten patients, of which five had large MCA aneurysms and three had giant ones. Fusiform unruptured aneurysms represented seven of all ten aneurysms. Angiographic and clinical follow-up were available for all patients mostly between 7 and 12 months. We had no technical complications, one periprocedural morbidity, and no mortality. On follow-up, we had no hemorrhagic complications, no aneurysms rupture, and only one clinically significant thromboembolic event in a patient who discontinued antiplatelet therapy against medical advice. One patient had completely occluded his diseased vessel but remained asymptomatic. The overall complication rate is 3/10. On follow-up, complete occlusion occurred in seven patients (7/9). PED treatment for large, giant, and bifurcation MCA aneurysms was feasible, with satisfying complete occlusion rate, no mortality, and reasonable morbidity rate.

Abstract W MP31: Thrombotic and Hemorrhagic Complications After Pipeline Embolization - A Platelet Aggregation and Transcranial Doppler Study

In this study, we sought to determine the correlation between the pre-treatment platelet aggregation, and the respective occurrence of thrombotic and hemorrhagic complications after pipeline embolization device (PED) for treatment of intracranial aneurysms. In addition, we evaluated the cerebral hemodynamics and the presence of silent emboli after PED placement in some patients utilizing transcranial Doppler (TCD). Methods: We analyzed the clinical and imaging characteristics of 46 consecutive patients who underwent 48 PED procedures. All patients received double antiplatelet therapy with Clopidogrel 75mg and Aspirin 325mg daily for at least 3 days prior to the planned procedure. Platelet aggregation testing was performed in 41/48 (86%) procedures. Based on the initial ADP % inhibition, patients were divided in 3 groups in the present study: 1) poor responders: <50%, 2) satisfactory responders: 50-75%, and 3) over-responders: > 75% Results: Hemorrhagic complications requiring escalation of care occurred in 15% (7/48) of all procedures, including 3 patients with symptomatic ICH. 2/3 ICHs occurred in a remote vascular territory in reference to the treated aneurysm, one of which was fatal. Thrombotic complications occurred at a rate of 13% (6/48), of which 3 (9%) were symptomatic. Permanent complication-related morbidity and mortality at 6 months was 4% (2/48). Of all patients with available platelet aggregation testing (n=41), 13 (31%) were poor Clopidogrel responders. Of those, 6 were switched to an alternative antiplatelet regimen. Thrombotic complications occurred mostly in the poor responders group who had no change in their regimen (27% vs. 4%; p=0.05). Intracranial hemorrhage occurred entirely in the over-responders group, (0% vs. 14%; p=0.08). None of the TCD demonstrated presence of silent emboli. In addition, 10/11 patients had elevated flow velocities after the PED placement. Conclusions: 1. Pre-treatment Clopidogrel response, measured by ADP % inhibition may predict thrombotic and/or hemorrhagic complications after PED placement. 2. Distal embolization likely occurs mostly during, but not after the procedure as suggested by the TCD data in this study.

Abstract T MP19: Intreped Registry: Association of Procedure Time With Complications

Purpose: To assess the association of procedure time with neurologic adverse events post Pipeline Embolization Device (PED) placement for intracranial aneurysm treatment. Methods: In the IntrePED Registry, a retrospective review was performed at 17 centers to identify consecutive intracranial aneurysms treated with the PED following regulatory approval in the given country. All patients in whom at least one PED was placed and follow-up was available prior to IRB approval were enrolled. “Primary adverse events” included major stroke, major hemorrhage, and neurological mortality. Results: 793 patients with 906 aneurysms, including 311 large ICA, 536 other anterior and 59 posterior circulation aneurysms were enrolled and followed for a mean duration of 19.3 months. 689 (77%) of 906 aneurysms were saccular and 116(13%) were fusiform. 824 (91%) were unruptured. 308 (34%) treated with multiple PEDs. Incidence of major hemorrhage, stroke and neurological mortality was 2.4%, 4.7% and 3.8% respectively. Heparin was administered in 89% of the patients during the procedure. An average of 1.5 PEDs were utilized per case. The mean procedure time was 101.5 ± 50.5 mins. Patients with a major complication (major stroke, major hemorrhage, neurological mortality) had procedure time of 138.2 + 81.5 min, and those without a major complication had procedure time of 98.3 + 45.5 min (p< 0.001). A logistic regression incorporating aneurysm size and number of PEDs used still showed a highly significant relationship between major complications and procedure time (p<0.001) and also found aneurysm size to be an independent predictor of longer procedures (p=0.007). Conclusions: The present analysis of IntrePED Registry subjects demonstrates a strong association of procedure time with complication rates. Further analyses of factors leading to longer procedure times is needed.

Abstract W MP36: The Phenomenon of Delayed Pipeline Embolization Device Migration: Technical Considerations, Complication Avoidance, and Management.

Introduction: The Pipeline Embolization Device (PED) is a dedicated flow diverter designed to treat intracranial aneurysms. New safety concerns are emerging as neurointerventionalists accumulate experience with the device. In this study, we describe the phenomenon of spontaneous delayed migration of the PED and discuss important technical considerations for prevention and management of this complication. Methods: A total of 155 patients were treated with the PED at our institution from November 2010 to January 2013. Patients who had spontaneous delayed migration of their devices during the study period were prospectively identified. Results: Five patients (3.2%) were found to have spontaneous delayed migration of their PEDs. All 5 cases occurred late during the study period (second half of the cohort). The PED migrated proximally in 4 patients and distally in 1 patient. The migration distance was 11 mm on average (range, 5-20 mm). Mismatch in arterial diameter between inflow and outflow vessels was a constant finding. One patient suffered a subarachnoid hemorrhage and expired as a result of PED migration while one patient presented with complete middle cerebral artery occlusion and was left severely disabled. In the 3 remaining cases, PED migration led to renewed aneurysm filling. PED migration was managed conservatively in 1 patient, with parent vessel occlusion in 1, and with additional placement of PEDs in 3. Conclusion: Spontaneous delayed migration of the PED is a serious and potentially fatal complication. The device may migrate proximally or distally and result in aneurysm rupture or thrombotic events. Obtaining complete expansion of the PED, using a longer PED, increasing vessel coverage, adjunctive aneurysm coiling, and avoiding dragging and stretching of the PED are important preventive measures. Neurointerventionalists should be aware of this serious complication and take all necessary preventive measures.

Early angiographic occlusion of ruptured blister aneurysms of the internal carotid artery using the Pipeline Embolization Device as a primary treatment option

Background Data on the timing, durability and occlusion rate of treating ruptured blister cerebral aneurysms using the Pipeline Embolization Device (PED) are limited.Clinical presentationThree patients who presented with subarachnoid hemorrhages...

Intracranial Aneurysms: Midterm Outcome of Pipeline Embolization Device—A Prospective Study in 143 Patients with 178 Aneurysms

To evaluate the midterm clinical and angiographic outcomes after pipeline embolization device (PED) placement for treatment of intracranial aneurysms. This prospective nonrandomized multicenter study was approved by the review boards of all involved centers; informed consent was obtained. Patients (143 patients, 178 aneurysms) with unruptured saccular or fusiform aneurysms or recurrent aneurysms after previous treatment were included and observed angiographically for up to 18 months and clinically for up to 3 years. Study endpoints included complete aneurysm occlusion; neurologic complications within 30 days and up to 3 years; clinical outcome of cranial nerve palsy after PED placement; angiographic evidence of occlusion or stenosis of parent artery and that of occlusion of covered side branches at 6, 12, and 18 months; and clinical and computed tomographic evidence of perforator infarction. There were five (3.5%) cases of periprocedural death or major stroke (modified Rankin Scale [mRS] > 3) (95% confidence interval [CI]: 1.3%, 8.4%), including two posttreatment delayed ruptures, two intracerebral hemorrhages, and one thromboembolism. Five (3.5%) patients had minor neurologic complications within 30 days (mRS = 1) (95% CI: 1.3%, 8.4%), including transient ischemic attack (n = 2), small cerebral infarction (n = 2), and cranial nerve palsy (n = 1). Beyond 30 days, there was one fatal intracerebral hemorrhage and one transient ischemic attack. Ten of 13 patients (95% CI: 46%, 93.8%) completely recovered from symptoms of cranial nerve palsy within a median of 3.5 months. Angiographic results at 18 months revealed a complete aneurysm occlusion rate of 84% (49 of 58; 95% CI: 72.1%, 92.2%), with no cases of parent artery occlusion, parent artery stenosis (<50%) in three patients, and occlusion of a covered side branch in two cases (posterior communicating arteries). Perforator infarction did not occur. PED placement is a reasonably safe and effective treatment for intracranial aneurysms. The treatment is promising for aneurysms of unfavorable morphologic features, such as wide neck, large size, fusiform morphology, incorporation of side branches, and posttreatment recanalization, and should be considered a first choice for treating unruptured aneurysms and recurrent aneurysms after previous treatments. http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.12120422/-/DC1.

Single Center Experience With Pipeline Stent

Endovascular coil embolization is an established method of treatment for intracranial aneurysms. The pipeline embolization device (PED) is a low-porosity endovascular stent designed to reconstruct the parent artery and decrease blood flow into the aneurysm. To report a series of 36 patients treated with the PED. Thirty-six patients underwent PED placement for aneurysm at the Jefferson Hospital for Neuroscience from October 2010 to November 2011. Clinical charts were reviewed. Thirty-six patients with 42 aneurysms were treated (3 male; 33 female; ages, 34-82; mean age, 60.1 years). Forty-one aneurysms were located in the anterior circulation, whereas one was located at the vertebrobasilar junction. PED placement was successful in all patients and resulted in stasis within all treated aneurysms. Symptomatic postoperative complications were witnessed in 13.9% (n = 5) of patients. These complications included intracerebral hemorrhage (n = 4), dissection (n = 1), symptomatic stroke (n = 2), and death (n = 1). Treatment of simple or complex intracranial aneurysms with PEDs alone or in conjunction with coil embolization is technically feasible, and the deployment technique requires a high degree of endovascular skills. Major perioperative adverse events must be studied. Respect for the indications of the procedure is crucial to justify the risk.

Abstract 176: Largest United States Pipeline Case Series After PUFS: Feasability, Technique, and Complications

Largest US Pipeline Case Series After PUFS: Feasability, Technique, and Complications Object: Endovascular coil embolization is an established method of treatment for intracranial aneurysms. Incomplete occlusion and recanalization are potential pitfalls of this treatment, particularly in large, complex aneurysms. The pipeline embolization device(PED) is a low-porosity endovascular stent designed to reconstruct the parent artery and prohibit blood flow into the aneurysm. The resulting stasis in the aneurysm, which leads to thrombosis, and the subsequent endothelial incorporation of the stent is meant to provide curative protection from aneurysmal rupture. Following the FDA approval of the PED, the authors report the first case series of 25 patients who have undergone such embolization and examine feasibility, technique, early results, and complications. Methods: Twenty-five patients underwent PED placement for aneurysm at Jefferson Hospital for Neuroscience from October 2010 to July 2011. Clinical charts were reviewed for demographics, details of presentation, procedure, hospital course, and outcome. Results: Twenty-five patients with 31 aneurysms were treated in the series(2 male; 23 female; ages 34-82; mean age 60.9 years). All of the aneurysms were located in segments of the internal carotid artery(1 petrous, 1 lacerum, 13 cavernous, 2 clinoid, 12 ophthalmic, 2 superior hypophyseal). Patients presented with headache, cranial nerve palsy, TIA, recurrence, or as incidental findings. Four of the patients presented with recurrence after coil embolization; one patient was treated with PED after attempted coil embolization; one was treated for recurrence after prior PED placement. PED placement was successful in all patients. The number of stents used per patient ranged from 1 to 5, with most patients being treated with 1(n=6) or 2(n=13) PEDs. One aneurysm was treated with both PED and coil embolization. A postoperative complication or combination of complications were witnessed in 20%(n=5) of patients. These complications included intracerebral hemorrhage(n=3), dissection(n=1), stroke(n=2), and death(n=1). Follow-up angiograms have been performed for five patients, on average 31 days after embolization, with 1 of those 5 patients suffering from incomplete aneurysmal occlusion. Conclusion: This is the largest reported case series in the United States following the PUFS trial. Treatment of simple or complex intracranial aneurysms with PEDs alone or in conjunction with coil embolization is technically feasible with low chance of intraoperative complication. However, major perioperative adverse events must be studied. Respect for the indications of the procedure is crucial to justify the risk.

Patency of the ophthalmic artery after flow diversion treatment of paraclinoid aneurysms

In this study the authors determined the patency rate of the ophthalmic artery (OphA) after placement of 1 or more flow diversion devices across the arterial inlet for treatment of proximal internal carotid artery (ICA) aneurysms, and correlated possible risk factors for OphA occlusion. Nineteen consecutive patients were identified (mean age 53.9 years, range 23-74 years, all female) who were treated for 20 ICA aneurysms. In all patients a Pipeline Embolization Device (PED) was placed across the ostium of the OphA while treating the target aneurysm. Flow through the OphA after PED placement was determined by immediate angiography as well as follow-up angiograms (mean 8.7 months), compared with the baseline study. Potential risk factors for OphA occlusion, including age, immediate angiographic flow through the ophthalmic branch, status of flow within the aneurysm after placement of PEDs, whether the ophthalmic branch originated from the aneurysm dome, and number of PEDs placed across the ophthalmic branch inlet were correlated with patency rate. Patients were treated with 1-3 PEDs (3 aneurysms treated with placement of 1 PED, 12 with 2 PEDs, and 5 with 3 PEDs). In 17 (85%) of 20 treated aneurysms, no changes in the OphA flow were noted immediately after placement of the device. Two (10%) of 20 patients had delayed antegrade filling immediately following PED placement and 1 patient (5%) had retrograde flow from collaterals to the OphA immediately after placement of the device. One patient (5%) experienced delayed asymptomatic ICA occlusion; this patient was excluded from analysis at follow-up. At follow-up the OphA remained patent with normal antegrade flow in 13 (68%) of 19 patients, patent but with slow antegrade flow in 2 patients (11%), and was occluded in 4 patients (21%). No visual changes or clinical symptoms developed in patients with OphA flow compromise. The mean number of PEDs in the patients with occluded OphAs or change in flow at angiographic follow-up was 2.4 (SEM 0.2) compared with 1.9 (SEM 0.18) in the patients with no change in OphA flow (p = 0.09). There was no significant difference between the patients with occluded OphAs compared with nonoccluded branches based on patient age, immediate angiographic flow through the ophthalmic branch, status of flow through the aneurysm after placement of PEDs, whether the ophthalmic branch originated from the aneurysm dome, or number of PEDs placed across the ophthalmic branch inlet. Approximately one-quarter of OphAs will undergo proximal thrombosis when covered with flow diversion devices. Even though these events were well-tolerated clinically, our findings suggest that coverage of branch arteries that have adequate collateral circulation may lead to spontaneous occlusion of those branches.