Immediate and follow-up results for 44 consecutive cases of small (<10 mm) internal carotid artery aneurysms treated with the pipeline embolization device

Flow diversion of large internal carotid artery aneurysms with the surpass device: impressions and technical nuance from the initial North American experience

BACKGROUND

Flow diversion is an important tool for treatment of cerebral aneurysms, particularly large and giant aneurysms. The Surpass flow diverter is a new system under evaluation in the USA.

OBJECTIVE

To report our initial experience of 20 cases with the Surpass flow diverter to demonstrate its basic properties, the required triaxial delivery platform, and the methodologies used to deploy it during treatment of large internal carotid artery (ICA) aneurysms

METHODS

Twenty patients with ICA aneurysms ≥10 mm with ≥4 mm neck treated as part of the Surpass IntraCranial Aneurysm Embolization System Pivotal Trial (the SCENT trial; Stryker) were included. Details of patient demographics, aneurysm characteristics, and technical procedures were collected.

RESULTS

Twenty patients (mean age 63.3±1.3 years; range 51-72) with 20 unruptured aneurysms (mean size 13.4±0.9 mm; range 10-21 mm) were treated. For proximal access, 60% of cases had aortic arch ≥grade II, 55% had significant cervical ICA tortuosity, and 60% had cavernous ICA ≥grade II. The Surpass device was implanted in 19/20 (95%) cases. Of 19 cases, a single device was used in 18 cases (95%) and 2 devices in only 1 case (5%). Balloon angioplasty was performed in 8/19 cases (42%). Complete aneurysm neck coverage and adequate vessel wall apposition was obtained in all 19 cases.

CONCLUSIONS

Surpass is a next-generation flow diverter with unique device-specific and delivery-specific features compared with clinically available endoluminal flow diverters. Our initial experience demonstrates a favorable technical profile in treatment of large and giant ICA aneurysms.

TRIAL REGISTRATION NUMBER

NCT01716117.

Intracranial Infectious Aneurysm in Orbital Cellulitis

Infectious intracranial aneurysm and cavernous sinus thrombosis are rare complications of orbital cellulitis. We report the case of a 46-year-old male presenting with sinusitis and orbital cellulitis complicated by the development of an orbital mass. Following orbitotomy with debulking, the patient underwent bony orbital decompression for increasing proptosis postoperatively. While his exam stabilized, the patient developed complete ptosis and extraocular motor palsy in the contralateral eye after undergoing bilateral sinus debridement. Imaging was notable for the presence of a pseudoaneurysm of the internal carotid artery, which was treated with a stent. This report demonstrates rare complications of orbital cellulitis. These patients should be monitored carefully with noninvasive imaging studies, such as cerebral angiography, for early detection of vascular abnormalities that can progress rapidly.

Safety and efficacy of the Pipeline Embolization Device in 100 small intracranial aneurysms

OBJECT Flow diverters are increasingly used for treatment of intracranial aneurysms. In most series, the Pipeline Embolization Device (PED) was used for the treatment of large, giant, complex, and fusiform aneurysms. Little is known about the use of the PED in small aneurysms. The purpose of this study was to assess the safety and efficacy of the PED in small aneurysms (≤ 7 mm). METHODS A total of 100 consecutive patients were treated with the PED at the authors' institution between May 2011 and September 2013. Data on procedural safety and efficacy were retrospectively collected. RESULTS The mean aneurysm size was 5.2 ± 1.5 mm. Seven patients (7%) had sustained a subarachnoid hemorrhage. All except 5 aneurysms (95%) arose from the anterior circulation. The number of PEDs used was 1.2 per aneurysm. Symptomatic procedure-related complications occurred in 3 patients (3%): 1 distal parenchymal hemorrhage that was managed conservatively and 2 ischemic events. At the latest follow-up (mean 6.3 months), 54 (72%) aneurysms were completely occluded (100%), 10 (13%) were nearly completely occluded (≥ 90%), and 11 (15%) were incompletely occluded (< 90%). Six aneurysms (8%) required further treatment. Increasing aneurysm size (OR 3.8, 95% CI 0.99-14; p = 0.05) predicted retreatment. All patients achieved a favorable outcome (modified Rankin Scale Score 0-2) at follow-up. CONCLUSIONS In this study, treatment of small aneurysms with the PED was associated with low complication rates and high aneurysm occlusion rates. These findings suggest that the PED is a safe and effective alternative to conventional endovascular techniques for small aneurysms. Randomized trials with long-term follow-up are necessary to determine the optimal treatment that leads to the highest rate of obliteration and the best clinical outcomes.

Impact of Endovascular Technique on Fluoroscopy Usage: Stent-Assisted Coiling versus Flow Diversion for Paraclinoid Internal Carotid Artery Aneurysms

Flow diversion is increasingly being utilized for the treatment of internal carotid artery (ICA) aneurysms. The purpose of this study was to evaluate the impact of endovascular technique--flow diversion versus stent-assisted coiling (SAC) on fluoroscopy time in patients treated for wide-neck paraclinoid ICA aneurysms. A retrospective review identified the 20 most recent consecutive patients treated for wide-neck paraclinoid ICA aneurysms by flow diversion and SAC respectively. Fluoroscopy time, cumulative dose area-product (DAP), contrast usage, intra-procedural complications, and total procedure time were collected and compared between the two treatment techniques. Treatment groups were comparable in terms of demographics, contrast usage, and clinical and angiographic outcomes. Flow diversion was associated with a significant reduction in fluoroscopy time (52.0 minutes versus 77.4 minutes), and demonstrated a strong trend towards shorter total procedure time (172 minutes versus 202 minutes). Average patient radiation exposure as measured by DAP was lower in the flow diversion group, 13225 mGy(x)cm(2) versus 15124 mGy(x)cm(2), although this finding was not statistically significant. There was no significant difference in contrast usage between the two groups, 152 ml and 159 (flow diversion and SAC respectively). The rate of complete aneurysm occlusion was higher in the flow diversion group (80% versus 60%). Endovascular treatment of paraclinoid ICA aneurysms with flow diversion is associated with shorter fluoroscopy times compared to stent-assisted coiling. There is also a likely reduction in overall procedure time. These results should be considered when recommending a treatment course for patients with such lesions.

Effect of antiplatelet therapy and platelet function testing on hemorrhagic and thrombotic complications in patients with cerebral aneurysms treated with the pipeline embolization device: a review and meta-analysis

Purpose

The pipeline embolization device (PED) necessitates dual antiplatelet therapy (APT) to decrease thrombotic complications while possibly increasing bleeding risks. The role of APT dose, duration, and response in patients with hemorrhagic and thromboembolic events warrants further analysis.

Methods

A PubMed and Google Scholar search from 2009 to 2014 was performed using the following search terms individually or in combination: pipeline embolization device, aneurysm(s), and flow diversion, excluding other flow diverters. Review of the bibliographies of the retrieved articles yielded 19 single and multicenter studies. A statistical meta-analysis between aspirin (ASA) dose (low dose ≤160 mg, high dose ≥300 mg), loading doses of APT agents, post-PED APT regimens, and platelet function testing (PFT) with hemorrhagic or thrombotic complications was performed.

Results

ASA therapy for ≤6 months post-PED was associated with increased hemorrhagic events. High dose ASA ≤6 months post-PED was associated with fewer thrombotic events compared with low dose ASA. Post-PED clopidogrel for ≤6 months demonstrated an increased incidence of symptomatic thrombotic events. Loading doses of ASA plus clopidogrel demonstrated a decreased incidence of permanent symptomatic hemorrhagic events. PFT did not show a statistically significant relationship with symptomatic hemorrhagic or thrombotic complications.

Conclusions

High dose ASA >6 months is associated with fewer permanent thrombotic and hemorrhagic events. Clopidogrel therapy ≤6 months is associated with higher rates of thrombotic events. Loading doses of ASA and clopidogrel were associated with a decreased incidence of hemorrhagic events. PFT did not have any significant association with symptomatic events.

Curative reconstruction of a cerebral aneurysm by flow diversion with the Pipeline embolisation device in a patient with Loeys-Dietz syndrome

Loeys-Dietz syndrome is a recently described connective tissue disorder with a natural history of extreme vessel tortuosity and aggressive arterial aneurysm formation and rupture. This is the case of a 23-year-old woman with a large, dysplastic cavernous aneurysm who had successful endovascular treatment by flow diversion with the Pipeline embolisation device. Ten-month follow-up demonstrated complete aneurysm occlusion and curative reconstruction of the parent vessel without evidence of vessel injury or dissection. Endovascular treatment with flow-diverting devices is a valid treatment option and can be performed safely and effectively in this complex patient population.

Focal, transient mechanical narrowing of a pipeline embolization device following treatment of an internal carotid artery aneurysm

Flow diversion is a promising technique for cerebral aneurysm treatment but presents new and sometimes unique challenges. Transient reversible narrowing due to device reconfiguration of the pipeline embolization device (PED) has not been previously described. Here we describe a patient with dolichoectasia of the distal right internal carotid artery with an associated saccular sidewall aneurysm who developed asymptomatic circumferential narrowing of the proximal aspect of the PED in the first month following deployment. The patient was followed conservatively and demonstrated partial resolution of device narrowing on 6 month follow-up imaging.

Focal, transient mechanical narrowing of a pipeline embolization device following treatment of an internal carotid artery aneurysm

Flow diversion is a promising technique for cerebral aneurysm treatment but presents new and sometimes unique challenges. Transient reversible narrowing due to device reconfiguration of the pipeline embolization device (PED) has not been previously described. Here we describe a patient with dolichoectasia of the distal right internal carotid artery with an associated saccular sidewall aneurysm who developed asymptomatic circumferential narrowing of the proximal aspect of the PED in the first month following deployment. The patient was followed conservatively and demonstrated partial resolution of device narrowing on 6 month follow-up imaging.

Transvenous approach for the treatment of direct carotid cavernous fistula following Pipeline embolization of cavernous carotid aneurysm: a report of two cases and review of the literature

Flow diverters are increasingly used for the endovascular treatment of cerebral aneurysms. A rare complication from flow diversion is delayed aneurysm rupture, which can lead to carotid-cavernous fistula (CCF) in the setting of cavernous carotid aneurysms (CCAs). Direct CCFs pose unique management challenges, given the lack of transarterial access to the fistula. We present two cases of direct CCFs following treatment of CCAs with the Pipeline embolization device (PED). Case 1 was a middle-aged patient with a symptomatic 10 mm wide-necked left CCA. Six weeks after PED treatment the patient developed diplopia secondary to direct CCF. Case 2 was a middle-aged patient with a symptomatic 17 mm left CCA treated with PED. One-month follow-up angiography demonstrated a direct CCF. Both patients underwent successful coil embolization of the CCF through a transvenous approach. Direct CCF formation following PED deployment for CCA is a rare complication. Parent vessel sacrifice may be avoided with transvenous occlusion of the fistula.

Radiation dose analysis of large and giant internal carotid artery aneurysm treatment with the pipeline embolization device versus traditional coiling techniques

BACKGROUND

Flow diversion is an effective and increasingly accepted method for endovascular treatment of cerebral aneurysms. Additionally, the public has heightened concerns regarding radiation exposure from medical procedures. This study analyzes radiation dose and fluoroscopy time during treatment of large and giant proximal internal carotid artery (ICA) aneurysms with the pipeline embolization device (PED) versus traditional coiling techniques.

METHODS

Radiation dose, fluoroscopy time, and contrast dye administration were retrospectively analyzed in 55 patients undergoing endovascular treatment of aneurysms ≥ 10 mm from petrous to superior hypophyseal ICA segments. Patients were treated by either PED (37 patients) or traditional coiling techniques (18 patients). Aortic arch type and proximal ICA tortuosity were also assessed as markers of access difficulty.

RESULTS

Average radiation dose with PED treatment was 2840 ± 213 mGy and 4010 ± 708 mGy with traditional coiling techniques (p=0.048; 29% decrease with PED). Mean fluoroscopy time for PED was 56.1 ± 5.0 min and 85.9 ± 11.9 min for coiling cases (p=0.0087; 35% decrease with PED). These benefits existed despite more difficult arch anatomy and a trend towards greater proximal vessel tortuosity in PED cases. Contrast dye amounts were also reduced by 37.5% in PED cases (75 ± 6 mL) versus coiling cases (120 ± 13 mL, p=0.0008).

CONCLUSIONS

Treatment of large and giant proximal ICA aneurysms using PED requires less radiation, less fluoroscopy time, and less contrast administration than standard coiling techniques. This further demonstrates the benefits of flow diversion for treatment of these aneurysms.

Quantitative analysis of high-resolution, contrast-enhanced, cone-beam CT for the detection of intracranial in-stent hyperplasia

BACKGROUND

Intracranial in-stent hyperplasia is a stroke-associated complication that requires routine surveillance.

OBJECTIVE

To compare the results of in vivo experiments to determine the accuracy and precision of in-stent hyperplasia measurements obtained with modified C-arm contrast-enhanced, cone-beam CT (CE-CBCT) imaging with those obtained by 'gold standard' histomorphometry. Additionally, to carry out clinical analyses comparing this CE-CBCT protocol with digital subtraction angiography (DSA).

METHODS

A non-binned CE-CBCT protocol (VasoCT) was used that acquires x-ray images with a small field-of-view and applies a full-scale reconstruction algorithm providing high-resolution three-dimensional (3D) imaging with 100 µm isotropic voxels. In an vivo porcine model, VasoCT cross-sectional area measurements were compared with gold standard vessel histology. VasoCT and DSA were used to calculate in-stent stenosis in 23 imaging studies.

RESULTS

Porcine VasoCT cross-sectional stent, lumen, and in-stent hyperplasia areas strongly correlated with histological measurements (r(2)=0.97, 0.93, 0.90; slope=1.14, 1.07, and 0.76, respectively; p<0.0001). Clinical VasoCT percentage stenosis correlated well with DSA percentage stenosis (r(2)=0.84; slope=0.76), and the two techniques were free of consistent bias (Bland-Altman, bias=3.29%; 95% CI -14.75% to 21.33%). An illustrative clinical case demonstrated the advantages of VasoCT, including 3D capability and non-invasive IV contrast administration, for detection of in-stent hyperplasia.

CONCLUSIONS

C-arm VasoCT is a high-resolution 3D capable imaging technique that has been validated in an animal model for measurement of in-stent tissue growth. Successful clinical implementation of the protocol was performed in a small case series.