bluuebunny/crossref_metadata_2025 huggingface dataset:
P-005 A novel three-dimensional (3D) revascularization device: histopathology results from a rabbit model and early clinical experience with the penumbra separator 3D
Authors: Weber J , Jansen O , Rohr A , Knauth M , Schramm P , Grand M , Weber W , Loehr C , Doerfler A , Struffert T , Goelit P , Zimmer C , Prothmann S , Boeckh-Behrens T
Published: July 2012

Introduction/Purpose

We report on the histopathology results from a preclinical rabbit study and our early clinical experience with the Separator 3D device, featuring novel 3D chambers for securing and removing thrombus. Compatibility with differently sized catheters provides flexibility to combine with aspiration.

Materials and Methods

To evaluate vascular responses of multiple 3D deployments and resheathings, a rabbit elastase model study examined right and left subclavian arteries from five rabbits 30 days after eight cycles. Vessels were subjected to histopathology analysis. Case experience in six European centers was collected in the first 30 days post-device approval. Fourteen consecutive patients presenting with acute ischemic stroke within 8 h of symptom onset were treated with the 3D device. Five cases involved ICA to MCA (M1 or M2) occlusion; four involved M1 segmental occlusion; two involved M1 to M2 occlusion; one involved basilar to PCA occlusion; two were excluded due to underlying stenosis. In the two cases involving stenosis, use of the 3D device followed by other stent retrievers like Solitaire (Covidien), Trevo (Stryker), and Restore (Reverse Medical) could not achieve revascularization; they were eventually resolved by balloon or stent.

Results

Multiple 3D deployment and resheathing cycles in the rabbit revealed no histopathologic lesions at 500 μm magnification nor evidence of injury or inflammation in the internal elastic lamina. Notably, no intraluminal fibrin or thrombus was found. In a multi-center case review study, the 3D device achieved 92% revascularization to TICI 2B or 3, excluding stenotic cases. In all cases, the 3D was successfully delivered to the occlusion site resulting in successful recanalization with 1.5 average passes. No vessel injury, vasospasm, or embolization of new territory was observed.

Conclusion

Preliminary results demonstrate that the Penumbra Separator 3D is a safe, effective revascularization device. Early animal and clinical experience with the 3D device appears promising. Absence of vessel injuries or new territory emboli may be aided by intraluminal 3D chambers that engage and remove clot with aspiration applied close to the lesion site. Smooth delivery and easy handling of the 3D was noted even in highly tortuous anatomy. Further case experience is warranted to confirm these promising initial observations.

Competing interests

None.
P-006 Angiographic and clinical outcomes after endovascular therapy for acute ischemic stroke due to vertebrobasilar occlusions: pooled analysis of the Merci Registry, MERCI, and multi MERCI trials
Authors: Nogueira R , Jovin T , Smith W , Rymer M , Liebeskind D , Budzik R , Devlin T , Walker G , Lutsep H
Published: July 2012

Objective

To describe the results of endovascular thrombectomy in a large prospective cohort of Acute Basilar Artery Occlusion (BAO) patients.

Background

BAO is a serious but uncommon condition accounting for only 6%–10% of large-vessel strokes.

Design/Methods

Our cohort included all BAO patients from three different prospective thrombectomy studies - the MERCI trial, the Multi MERCI trial, and the MERCI Registry. Successful recanalization was defined as TIMI 2–3 in the Merci/Multi-Merci trials and TICI 2–3 in the Merci Registry. Good Outcomes was defined as 90-day mRS 2.

Results

Ninety-nine patients were identified (mean age, 61.6±15 years (range, 31–93); male gender, 70.7%; mean baseline NIHSS, 20.5±9.4 (median, 19); baseline mRS0-1, 95.9%). Fourteen patients (14.1%) received pre-procedure IV rt-PA. The mean time-from-symptom-onset (TSO) to arterial puncture was 9.23±12.45 h (median, 6.15) with 34.1% of patients treated >8 h. All patients were treated with at least one pass of Merci (average, 2.3±1.6). Other treatments included: intra-arterial rt-PA/urokinase (53.5%), proximal angioplasty (22.1%, 19/86) or stenting (14.0%, 12/86), Penumbra (15.3%, 11/72), and other mechanical (29.1%, 25/86). Successful recanalization was achieved in 88.9% (88/99). The overall mean (median) NIHSS dropped from 20.5±9.4/19 on admission to 13.4±14.5/6 on discharge. The overall rate of good outcomes was 31.6% (31/98). 90-day mortality was 38.8% (38/98). The SICH rate was 8.9% (7/79). The rate of good outcome was numerically higher (34.5% vs 9.1%) and mortality was numerically lower (36.8% vs 54.5%) in the revascularized vs non-revascularized patients. Notably, only one of 31 (3.2%) patients achieved a good outcome in the absence of recanalization. Patients with good outcome had significantly lower age (56.6 vs 63.6), baseline NIHSS (14.86 vs 23.15), and hypertension (51.6% vs 73.1%) but higher baseline functional status (mRS 0–1, 100% vs 93.8%) as compared to patients with bad outcomes. However, there was no difference in terms of TSO to puncture (9±13 vs 9±13 h), glucose levels (130±27 vs 152±62 mg/gl), intubation (82.6% vs 90.4%), or treatment modalities between these two groups.

Conclusions

Mechanical thrombectomy in BAO appears to be associated higher recanalization rates than previous reports of intravenous or intra-arterial thrombolysis. In concordance to previous studies, the chances of good outcomes are dismal in the absence of recanalization.

Competing interests

R Nogueira: Concentric Medical, Inc., ev3 neurovascular, Coaxia, Rapid Medical. T Jovin: Concentric Medical; ev3 neurovascular; Coaxia. W Smith: Concentric Medical. M Rymer: Genetech. D Liebeskind: Concentric Medical; Coaxia. R Budzik: Concentric Medical. T Devlin: None. G Walker: Concentric Medical, Inc. H Lutsep: Concentric Medical.
P-009 Endovascular balloon-augmented embolization of intracranial and cervical arteriovenous malformations using a dual lumen coaxial balloon microcatheter: initial experience: Abstract P-009 Figure 1
Authors: Grigoryan M , Hassan A , Tummala R , Tekle W , Seidel G , Jagadeesan B
Published: July 2012

Background

Transarterial embolization with ethylene vinyl alcohol copolymer (EVOH) Onyx (ev3, Neurovascular, Irvine, CA) is a popular method for endovascular management of arteriovenous malformations (AVMs) and fistulas. Successful embolization depends on antegrade flow of Onyx following initial formation of a proximal plug. Plug formation can be unpredictable, time consuming and can result in catheter retention. To avoid the need for forming a proximal plug, we recently adopted Onyx embolization through a coaxial balloon microcatheter.

Methods

We performed a series of five consecutive Onyx embolizations via seven arterial feeders in four patients using the Scepter C (Microvention Inc, Tustin, CA), a coaxial balloon catheter with an inner lumen for a guidewire and an outer lumen for balloon inflation/deflation. In each case, the catheter was navigated into the feeding artery over an 0.014 wire. After removing the wire, the balloon was then carefully inflated to arrest the flow and prevent reflux of Onyx. The inner lumen was primed dimethyl sulfoxide and Onyx 18 or 34 was then infused under continuous fluoroscopic visualization. Embolizations were terminated following adequate penetration of the AVM nidus. The balloon was then deflated and catheter was slowly removed without difficulties.

Results

The balloon catheter showed excellent navigability and there were no complications involving its inflation, deflation, or retrieval. There was no reflux of Onyx. Excellent penetration into the AVM nidus was achieved during all sessions. No untoward embolization into the normal cerebral circulation has occurred. None of the patients suffered peri- or postprocedural complications.

Conclusions

Onyx embolization via a coaxial lumen Scepter C balloon catheter allows for great penetration while obviating the need for the usual “plug and push technique”. It reduces procedure time and radiation exposure. Due to its current availability in only one size (4 mm), the technique may be safest in larger diameter arterial feeders.

Competing interests

None.

Abstract P-009 Figure 1
E-010 Preoperative embolization of meningioma with dural branch of internal carotid artery
Authors: Hirohata M , Takeuchi Y , Sakata K , Marioka M
Published: July 2012

Purpose

One of the most important issues in the surgical treatment of large hypervascular meningiomas is the securing and coagulation of feeding arteries. However, securing the feeding artery prior to actual tumor resection might be difficult in tumors with a feeding artery arising from the deep surface of the operative field. For such cases, we performed selective feeder embolization before tumor resection. This study evaluated the clinical usefulness of preoperative embolization of the dural branch of the internal carotid artery (ICA) for brain tumor.

Clinical material

Subjects comprised 21 consecutive patients with large hypervascular meningioma fed by ICA dural branche (Meningohypophyseal artery: 14, Infero-lateral trunk: 9, Ethomoidal Artery: 1) Feeder embolizations were performed under local anesthesia 1 day before tumor resection. 2 or 1.7 F microcatheter and hydrophilic shapable micro guide wire and PVA (150–250 μ) were used.

Results

Maximum tumor size were 30 to 72 (mean: 45.9) mm Almost complete embolization was obtained in nine patients, and a marked decrease in tumor staining was demonstrated in 13 patients. No complications related to endovascular procedures were encountered. Intraoperative control of bleeding was easily manages, with mean intraoperative blood loss of 536 ml. Although partial resection was possible due to cranial nerve adhesion to the tumor in two cases, total or sub total resection was achieved in 19 cases.

Conclusion

Endovascular embolization of the feeding artery from ICA dural branch was safe and effective adjuvant therapy before tumor resection.

Competing interests

None.
E-013 Coil herniation and retinal/vitreous hemorrhage in a patient with antiphospholipid antibody syndrome undergoing balloon assisted coil embolization of unruptured ICA aneurysm: Abstract E-013 Figure 1
Authors: Gupta V , Gandhi C , Prestigiacomo C , Bhagat N , Turbin R , Gupta G
Published: July 2012

Antiphospholipid antibody syndrome (APS) is a well-recognized cause of hyper coagulation causing arterial/venous thrombosis and/or pregnancy morbidity. Thromboembolic complications remain the main concern during endovascular coil embolization of aneurysms. Retinal and vitreous hemorrhages in association with this syndrome as a post coiling complication of unruptured intracranial aneurysm has not been previously reported. We report the case of a 48-year-old woman with underlying APS who underwent balloon assisted coil embolization of an unruptured right ICA aneurysm. There was herniation of the second coil requiring coil retrieval with subsequent non flow limiting herniation of the first coil left in situ on anticoagulation. In the immediate post procedure period, she developed preretinal, intraretinal and vitreous hemorrhages requiring temporary withholding anticoagulation therapy with careful resumption. Retinal/vitreous hemorrhages in a patient with APS presents a complex management challenge in the context of a herniated coil loop during endovascular aneurysm therapy.

Competing interests

None.

Abstract E-013 Figure 1
E-014 Endovascular occlusion of trigeminal artery-cavernous fistula following spontaneous rupture of a persistent trigeminal artery (PTA): technical considerations and case report: Abstract E-014 Figure 1
Authors: Fortes M , Jindal G , Gomez J , Gandhi D
Published: July 2012

Purpose

To report a rare case of spontaneous rupture of dysplastic trigeminal artery in the cavernous sinus, imaging findings and technical considerations for treatment with vessel preservation.

Case report

A 47-years-old female presented to the emergency department with acute onset of left eye pain, redness, elevated intra-ocular pressure and left third nerve palsy.

Imaging findings

CT angiography obtained at admission showed a dilated left cavernous sinus and a suspicion that there may be ipsilateral PTA. Digital subtraction angiogram (DSA) of the left internal carotid artery (ICA) demonstrated a very high flow carotid-cavernous fistula but the exact location of the tear was impossible to find on anterior circulation injection. An analysis of left vertebral injection, 3D-DSA and DynaCTTM demonstrated and mapped the location of the tear in proximal PTA. Vessel preservation was considered necessary since the left anterior inferior cerebellar artery arose from the PTA. Dual catheter access was obtained (left ICA and left vertebral) and the fistula catheterized from the basilar artery aspect of the PTA. Additional micro-catheter was placed across from left ICA into PTA across the tear in case a stent would be necessary to reconstruct the PTA. Complete coil occlusion of the fistula could be accomplished and stent was not required. The patient recovered fully from this fistula and 3rd nerve function was normal at 2-weeks follow-up.

Persistent trigeminal artery is an anatomic variant seen in 0.1%–0.6% of cerebral DSAs. Although a handful of cases of PTA related carotid-cavernous fistula are reported in the literature, a determination that the tear was spontaneous and not related to underlying aneurysm is difficult or impossible. Our case demonstrates the utility of careful imaging in the angiography suite with the inclusion of DynaCTTM and simultaneous dual catheter (ICA and Vertebral) 3D imaging for evaluation. A well-planned endovascular approach is key when preservation of the parent vessels with closure of the fistula is the goal.

Competing interests

None.

Abstract E-014 Figure 1

(A) Coronal reconstruction from DynaCT shows left cavernous ICA (short black arrow), PTA (long black arrow) and carotid cavernous fistula (white arrow). (B) Left ICA coronal view DSA shows intense early venous drainage to the cavernous sinus.
E-020 Initial multi-center international experience with the target detachable coil
Authors: Turk A , Machi P , Chaudry M , Bonafe A , Turner R
Published: July 2012

Background

Aneurysm coil technology has evolved to require near instant detachment times and near perfect detachment performance. We evaluated the new Target coil to determine device safety and acute performance.

Materials and Methods

At two large high volume international centers, between November 2010 and February 2012, 211 aneurysms were coiled with Target coils; 127 elective and 84 ruptured. Average aneurysm dimensions were 5.51 mm × 4.01 mm × 3.89 mm with 17% PCOM, 21% ICA, 31% ACOM and the remaining Basilar, MCA and Vertebral. 62% of the cases were treated with balloon assisted coiling, 5% were stent assisted coiling, and 7% utilized both balloons and stents. 77% of the cases achieved a Raymond Scale of 1, 21% achieved a Raymond scale of 2, and 1.5% were Raymond Scale of 3. We experienced a 5% procedural complication rate, of which 4% were thromboembolic. There was one vessel injury related to balloon remodeling, one vessel perforation retrieving an errant coil and one perforation during coiling. Detachment times were evaluated in the first 26 cases utilizing 11 coils and showed all coils detached, with 90% in the first cycle. The original detachment time was 7.1 s. The detachment handle was altered to shorten the detachment cycle after the first 44 coils. The detachment time was then found to be 5.7 seconds for the last 67 coils. We continue to use the coils and will update results at time of the meeting.

Discussion

The new Target coil combines the device performance of the GDC coil with an advanced pusher wire and detachment mechanism that allowed rapid and reliable coil performance. This can translate into faster operating times with improved device performance resulting in safer operations and better clinical outcomes.

Competing interests

A Turk: Stryker. P Machi: None. M Chaudry: None. A Bonafe: None. R Turner: None.
E-021 Initial experience using the Penumbra Coil 400: comparison of aneurysm packing and coil efficiency
Authors: Milburn J , Pansara A , Martinez R , Vidal G
Published: July 2012

Introduction

Penumbra Coil 400 gained FDA approval and was introduced to the market April 2011. Due to its larger 0.020″ diameter and inherent softness, there is potential to provide more efficient coiling. More efficient coiling may result in shorter catheter in vessel time and less radiation exposure for the patient and healthcare team. This is a retrospective single operator experience of aneurysm coiling at the Ochsner Clinic comparing the Penumbra Coil 400 with the other most commonly used coil types, Orbit and Galaxy.

Methods

Forty aneurysms treated exclusively with Orbit or Galaxy coils and 18 aneurysms treated only with Penumbra coils from 2010 to February 2012 were compared. There were 36 other aneurysm treatments excluded because they were not initial treatments, other manufacturers' coils were used, or they had mixed coil types. Measurements included packing density, number of coils per unit aneurysm volume, and total coil length per unit aneurysm volume. Other parameters including presenting aneurysm rupture status, frequency of stent or balloon use, aneurysm occlusion rates, and complications were also compared.

Results

Mean packing density of 33.7% using Penumbra coils was significantly >24.4% for Orbit/Galaxy coils (p=0.0001). Number of coils per aneurysm volume of 0.026 coils/mm3for Penumbra was significantly lower than 0.114 coils/mm3for Orbit/Galaxy (p<0.001). Total coil length per aneurysm volume of 0.11 cm/mm3for Penumbra was significantly <0.32 cm/mm3for Orbit/Galaxy treatments (p<0.001). Aneurysm sizes ranged from 6.3 mm3to 5564.0 mm3in the Orbit/Galaxy group and from 31.0 mm3to 12 666.4 mm3in the Penumbra group. There were more ruptured aneurysms treated using Orbit/Galaxy (67%) than with Penumbra (28%). Aneurysm occlusion rates and frequency of balloons or stent use was similar in both groups. There were no procedural complications in the Penumbra cases, and there were two small branch infarctions in the Orbit/Galaxy group that were not clinically apparent.

Conclusion

In our practice, aneurysm treatments with the Penumbra 400 coil have resulted in significantly greater average packing density using less than one fourth of the number of coils per volume compared with Orbit/Galaxy. Aneurysms were larger in the penumbra group, and more ruptured aneurysms were treated with Orbit/Galaxy. Occlusion rates and complication rates were similar and acceptable in both groups.

Competing interests

J Milburn: Penumbra. A Pansara: None. R Martinez: None. G Vidal: None.
E-022 Tandem symptomatic internal carotid artery and persistent hypoglossal artery stenosis treated by endovascular stenting and flow reversal: case report: Abstract E-022 Figure 1
Authors: Eller J , Jahshan S , Dumont T , Kan P , Levy E , Siddiqui A
Published: July 2012

The persistence of the hypoglossal artery (PHA) into adulthood is a very rare vascular anomaly and, when present, provides the only vascular supply to the posterior circulation. We describe a case of a 64-year-old male presenting with symptoms of vertebro-basilar insufficiency associated with severe high grade stenosis of a persistent hypoglossal artery and tandem stenosis of the proximal ipsilateral internal carotid artery (ICA), both treated by an endovascular approach. Given this patient's comorbidities and the potential anatomic difficulties presented by the PHA during performance of a carotid endarterectomy, we decided to proceed with stent placement in both the proximal ICA and the PHA in the same treatment setting. The high degree of stenosis in the PHA and the presence of a large atherosclerotic plaque in the proximal ICA were felt to be good indications for proximal embolic protection by a flow-reversal technique using the GORE Flow Reversal System (W.L.Gore and Associates, Inc., Flagstaff, AZ). The unique anatomical and technical challenges associated with this case are reviewed in detail. Post-operatively, the patient improved clinically, remaining with minimal subjective right sided numbness and he was discharged home on ASA, Effient and Crestor. The patient had no complications related to the endovascular procedure.

Competing interests

J Eller: None. S Jahshan: None. T Dumont: None. P Kan: None. E Levy: Stent Assisted Recanalization in Acute Ischemic Stroke—SARIS, Boston Scientific, Codman & Shurtleff, ev3/Covidien Vascular Therapies. Scientific Advisors to Codman and Shurtleff, ev3/Covidien Vascular Therapies, TheraSyn Sensors Inc., Intratech Medical Ltd., Mynx/Access Closure. Fees for carotid stenting training from Abbott Vascular, Fees for carotid stenting training from ev3/Covidien Vascular Therapies. A Siddiqui: National Institutes of Health (co-investigator NINDS 1RO1NS064592-01A1 Hemodynamic Induction of pathologic remodeling leading to intracranial aneurysms, Research Development Award from University at Buffalo. Codman & Shurtleff, Inc, Concentric Medical, ev3/Covidien Vascular Therapies, GuidePoint Global Consulting, Penumbra. Genentech. Abbott Vascular, American Association of Neurological Surgeons courses.

Abstract E-022 Figure 1
E-029 Balloon-augmented target vessel sacrifice with liquid embolic agents
Authors: Bhalla T , Spiotta A , Hui F
Published: July 2012

Introduction

Vessel sacrifice remains a valuable tool in the treatment of select vascular lesions. Conventionally, neurointerventionalists have relied on coil embolization as their primary means of vessel sacrifice since detachable balloons are no longer available. However, coil embolization can be expensive with long fluoroscopy times. We describe a novel technique for vessel sacrifice using temporary balloon occlusion to achieve proximal flow arrest in the parent vessel while embolizing the target vessel with a liquid embolic agent.

Methods

A total of three vessel sacrifices (two vertebral, one carotid) were performed in three patients. Balloons were employed to achieve proximal flow arrest to allow an Onyx (Covidien) cast to accumulate in the target vessel following the deposition of coils.

Results

Complete occlusion of the target vessel was achieved in all cases with no complications. Two balloons were employed, the Ascent (Covidien) and Scepter C (MicroVention). Between two and four coils and 0.3 to 0.7 cc of Onyx were employed resulting in significant cost, procedure and fluoroscopy time savings.

Conclusion

Vessel sacrifice using commercially available non-adhesive liquid embolic agents is feasible with balloon assistance, allowing for reduced radiation and material costs. Coils may be beneficial in providing an anchor point for liquid embolic deposition, as well as reducing the volume of liquid embolysate required to achieve vessel occlusion.

Competing interests

T Bhalla: None. A Spiotta: 1; C; Integra, Hemedex. F Hui: None.
E-032 Imaging characteristics of tumors of the head and neck: Abstract E-032 Figure 1
Authors: Hardman J , Kato C , Rezai P , Kumar G
Published: July 2012

Purpose

Tumors of the head and neck have characteristic findings on MRI and cerebral angiography which help with proper diagnosis and localization. This presentation will provide a review of the characteristic findings of tumors commonly found in the head and neck.

Materials and Methods

A retrospective analysis was made of head and neck tumor cases for the past 10 years from the PACS system at Cook County Hospital. All selected cases are biopsy proven.

Results

We compare and contrast the characteristic MRI and cerebral angiogram findings of glomus jugulare tumors, glomus vagale tumors, carotid body tumors, meningiomas, schwannomas, paragangliomas, central neurocytoma, orbital tumors and metastatic tumors. All of these tumors have typical locations and vascular patterns observed on MRI and cerebral angiography.

Conclusion

It is important to carefully analyze the imaging characteristics of tumors of the head and neck as this information will differentiate common tumors from the more complex ones. Each of these tumors have specific findings that use of MR and cerebral angiography, along with patient history, can help to determine further management. This review aims to refresh to the knowledge base of the neurointervenionalist in differentiating between these tumors.

Competing interests

None.

Abstract E-032 Figure 1
E-035 Ghost image extraction technique utilizing intraoperative angiography for the controlled removal of an intracranial nail: Abstract E-035 Figure 1
Authors: Braca J , Whapham J , Prabhu V
Published: July 2012

Penetrating intracranial trauma via nail gun injury is becoming more common and differs significantly from the sequelae of penetrating cranial trauma of gunshot wounds. Safe, effective extraction techniques are therefore necessary and can employ intraoperative angiography (IA). An (IA) Ghost Image Extraction technique for safe removal of an intracranial nail is described here and can be applied to future such situations. A 32-year-old right-handed male with a history of multiple, non-operative closed-head injuries presented complaining of a 3 day history of right retro-orbital headache, blurry vision in his right eye, and C8 distribution parasthesias on the left forearm. CT revealed a 6 cm nail lodged in the right posterior frontal lobe, with the distal tip pointing superior and medially, without evidence of intracranial hemorrhage along the tract. On more pointed questioning, the patient admitted to non-accidental trauma. On arrival to our facility, the patient was afebrile and without meningeal signs. He was neurologically intact with the exception of a subtle left pronator drift and decreased sensation to light-touch distally in the left C8 distribution. The patient went to the angiography suite for pre-operative vascular mapping prior to surgical extraction of the embedded nail. Four vessel cerebral angiography demonstrated the course of the major, distal branches and tributaries of the intracranial vessels and, miraculously, none were injured. Given the proximity of the nail to major intracranial vessels and elegant cortex, the consideration for safe, controlled extraction of the nail involved the use of IA. The five French sheath was left in place. In the operating room after curvilinear incision and appropriate exposure a double concentric craniotomy was performed around the head of the nail. At this point, with the assistance of intra-operative fluoroscopy and angiography, the nail was slowly and carefully removed under direct visualization so as to remove it in the identical course of its entry to avoid further intracranial injury. The subtracted ghost image of the nail (Abstract E-035 figure 1) that appears with IA allows for control of the distal tip of the nail by extraction via the nail's entry path so as to avoid inadvertent laceration of a vessel or further injury to elegant cortex. Periodic angiographic images were obtained during the deliberate extraction to ensure no intracranial vessel injury had occurred. Post-operative CT revealed a small hemorrhage in along the tract of the nail. The patient did well postoperatively.

Abstract E-035 Figure 1

Competing interests

None.
E-038 Acute histologic changes observed in swine arteries treated with a mechanical thrombectomy device: Abstract E-038 Figure 1
Authors: Yuki I , Kan I , Golshan A , Vinters H , Kim R , Yin N , Duckwiler G , Vinuela F , Murayama Y , Vinuela F
Published: July 2012

Background and purpose

Effectiveness of currently used mechanical thrombectomy devices has been evaluated using animal models mainly based upon the angiographical data analysis. However very little has been described about the histologic changes observed in the arteries treated with mechanical thrombectomy devices. The purpose of this study is to evaluate acute arterial histologic changes induced by mechanical thrombectomy using a dedicated swine stroke model.

Materials and Methods

A total of eight Superficial Cervical Arteries in four swine were occluded with experimental thrombus and treated using the Merci Clot Retrieval System®. Each treated artery was harvested immediately after the procedure and histologic analysis of each arterial sample was performed. Four untreated Superficial Cervical Arteries were used as controls.

Results

A total of 24 attempts at clot retrieval were made. The average number of retrieval attempts per artery was three. Circumferential intimal denudation and separation of smooth muscle layers in the tunica media were seen in all samples. The intimal denudation was seen regardless of the number of retrieval attempts. A minor sub-intimal dissection was seen in one artery. Arterial perforation with sub-adventitial hematoma was seen in two arteries and these findings were associated with microwire/microcatheter navigation rather than the use of the clot retrieval device.

Conclusion

Minor histologic changes including intimal denudation and separation of smooth muscle layers in tunica media were seen in every artery treated by mechanical thrombectomy. Two arteries that showed major histologic change (sub-adventitial hematoma) were both associated with microwire/catheter navigation rather than the use of the clot retrieval device. It is possible that major arterial injury (eg vessel perforation) during the mechanical thrombectomy is more likely to be associated with microcatheter/microwire navigation rather than clot retrieval itself. This animal model may be useful in the preclinical safety evaluation of the mechanical thrombectomy devices.

Competing interests

I Yuki: None. I Kan: None. A Golshan: None. H Vinters: None. R Kim: None. N Yin: None. G Duckwiler: Concentric Medical. F Vinuela: None. Y Murayama: None. F Vinuela: None.

Abstract E-038 Figure 1
E-004 Comparison of lesion and PH volumes: interventional management of stroke (IMS) I, II vs Solitaire Study: Abstract E-004 Table 1
Authors: Javadi A , Tomsick T , Carrozzella J
Published: July 2012

Introduction/purpose

Minimizing the ischemic damage to the brain after intracranial arterial occlusion is critical in improving the patient's prognosis. Solitaire FR Revascularization Device offers a potential new solution for quick recanalization of the occluded vessels, potentially reducing infarct volume and improving outcome. The purpose of this project is to assess and compare the effect of the Solitaire Device on patients' infarct and hemorrhage volume, as compared to combined IV/IA rtPA therapy in IMS I/II.

Methods

The 24-h CT (n=99) and MR images (n=10) from subjects in the retrospective Solitaire Study with ICA-T, M1, or M2 occlusions were made available for analysis. The volume of lesions (infarct + hemorrhage) was measured using volume measurement software. Volumes were compared to similar occlusions treated in the IMS I/II studies (n=89), previously measured in similar fashion. Any parenchymal hematoma (PH) was also separately measured and classified as PH1 or PH2. PH volumes were also compared between Solitaire Study and IMS I/II studies.

Results

In the Solitaire study, there were 9 PH1 (8.3%) and 6 PH2 (5.5%). In IMS, there were 12 (13.4%) PH1, and 6 (6.7%) PH2. Results of volume measurements, including subjects with no PH, are summarized in Abstract E-004 table 1.

Abstract E-004 Table 1

PH and lesion mean volumes, IMS I & II compared to Solitaire Study

IMS, I/II (n=89)Solitaire (n=109)p ValueMean lesion volume (all cases)80.661.60.056Parenchymal hematoma 1 (PH1) PH 1 volume ml14.69.50.17 Lesion (PH 1 + infarct) volume ml155.2132.2NSParenchymal hematoma 2 (PH2) PH 2 volume ml22.81010.004 Lesion (PH 2 + infarct) volume ml60.8167.50.03Non-PH lesion volume ml78.148.30.02

Conclusion

Significant differences in lesion volumes between the Solitaire Study and IMS I/II may indicate a clinical benefit in using Solitaire FR Revascularization Device for recanalization of occluded arteries. Other potential clinical and imaging contributors to volume differences will be analyzed and discussed. Whereas the findings reported are hypothesis generating, more conclusive prospective research is needed for confirming the findings of this preliminary analysis. Similar analysis in the recently-completed prospective, randomized SWIFT Study is planned.

Competing interests

A. Javadi: ev3/Covidian. T. Tomsick: ev3, Covidian. J. Carrozzella: ev3/Covidian.
E-040 Evaluation of peri-procedural blood loss in acute ischemic stroke patients undergoing endovascular revascularization
Authors: Noorian A , Rangaraju S , Owada K , Glenn B , Belagaje S , Anderson A , Frankel M , Gupta R , Nogueira R
Published: July 2012

Background

To date, there have not been any studies to evaluate the extent of blood loss and its significance in the hospital course of acute ischemic stroke (AIS) patients undergoing endovascular revascularization.

Objective

The aim of this study was to evaluate the extent of peri-procedural blood loss measured by hemoglobin (Hb) and hematocrit (HCT), in AIS patients undergoing endovascular revascularization.

Design/methods

Consecutive AIS patients in Grady Memorial Hospital were retrospectively analyzed. The AIS transfers from outside hospitals were excluded from this study given lack of available data about pre-procedure Hb/HCT levels. The HCT and Hb right before (PRE-HCT and PRE-Hb) and within 24 h after the endovascular procedure (POST-HCT and POST Hb) were recorded. Patients' demographic information, baseline NIHSS, site of occlusion, revascularization modalities, and the need for transfusion early after the procedure were documented. Descriptive statistics are provided.

Results

Forty-one patients (age 68±14; 46% male) with large vessel occlusions were included (26 patients with M1 occlusion, nine patients with M2/3 occlusion, seven patients with ICA occlusion and two patients with basilar/PCA occlusions). The mean NIHSS was 18. Patients had PRE and POST HCT/Hb of 39.3±5.3/ 13.1±1.8 and 34.5±5.3/ 11.5±1.8, respectively. The extent of drop from PRE to POST HCT/Hb (4.7±3.6/1.5±1.2) was statistically significant (paired t-test, p<0.0001). Six patients (14.6%) had HCT/Hb drop >9.0/3.0. The type of device (Merci vs Penumbra) and use of IV or IA-tPA was not associated with any differences in HCT/Hb drop. Only one patient (PRE HCT/Hb:34.9/11.9; POST HCT/Hb:24.6/8.3) required blood transfusion.

Conclusions

Our results suggest some extent of blood loss in endovascular management of acute stroke. However, clinically significant blood loss and blood transfusion requirement are uncommon. Future studies with higher number of patients are needed to further delineate this potential complication.

Competing interests

A Noorian: None. S Rangaraju: None. K Owada: None. B Glenn: None. S Belagaje: None. A Anderson: None. M Frankel: None. R Gupta: Concentric Medical, Codman Neurovascular, CoAxia, and Rapid Medical. R Nogueira: Concentric Medical, ev3 Neurovascular, CoAxia, and Rapid Me.
E-042 Immediate procedural outcomes in 35 consecutive pipeline embolization cases: a single-center, single-user experience
Authors: Colby G , Lin L , Gomez J , Paul A , Huang J , Tamargo R , Coon A
Published: July 2012

Background and Objective

Flow diverters are an exciting new class of endovascular devices that treat aneurysms by curative reconstruction of the parent artery. The Pipeline embolization device (PED; Covidien Vascular Therapies, Mansfield, Massachusets, USA) is the first FDA-approved intracranial flow diverting device available in the USA. We present our periprocedural results in a series of 35 consecutive PED cases.

Methods

All patients who underwent PED treatment of an intracranial aneurysm at our institution following FDA approval of the device in April 2011 were included in the series. Patient demographics, aneurysm characteristics, procedural details, and technical and clinical outcomes were analyzed.

Results

Thirty-four patients (range 23–78 years, mean age 56.4 years) with 41 unruptured aneurysms (37 anterior circulation, 4 posterior circulation, mean size 11.4 mm, 20/21 large or giant) were treated with the PED. Thirty-four of 35 cases (97%) were successfully completed. A total of 64 PEDs were implanted, with the mean number of PEDs implanted per anterior and posterior circulation cases of 1.2 PEDs and 6.5 PEDs, respectively. A single PED was implanted in 73% of cases. Immediate flow disruption occurred in 97% of the cases. The overal rate of major stroke or mortality was 3% (1 of 35 patients). Minor stroke, cranial nerve palsy, transient neurological deficit, and groin complication occurred in one patient each (3% each, 12% total).

Conclusion

Treatment of cerebral aneurysms with the PED carries an acceptable risk profile when a rigorous and uniform technique is used. Although the long-term results will need to be analyzed, the immediate procedural outcomes in our series using this technique appear quite promising.

Competing interests

G Colby: None. L Lin: None. J Gomez: None. A Paul: None. J Huang: None. R Tamargo: None. A Coon: Covidien.
E-046 Migration of enterprise self-expanding intracranial stent after successful deployment
Authors: Swarnkar A , Ezhapilli S , Lodi Y , Deshaies E
Published: July 2012

Introduction

Enterprise stent is used for stent-assisted coiling of wide-neck intracranial aneurysms. It is a self-expanding flexible stent and has a close cell design. There are reports of migration of the stent after initial successful deployment.1The purpose of this study is to describe the incidence and extent of migration of the Enterprise stent and its influence on coiling.

Materials and Methods

This retrospective study included 73 patients, (17 male and 56 females), with wide-necked intracranial aneurysms, who underwent stent assisted coiling using Enterprise stent over a period of 4 years. The results of the initial and follow-up cerebral angiograms were evaluated.

Results

Thirty four patients (47%) had no displacement of the stent. Thirty five patients (48%) had <1.5 mm displacement of the stent, which was considered not significant. Only four patients (5%) had more than 2 mm migration of the stent after deployment. One of these patients in whom the stent was deployed across a basilar apex aneurysm, had a proximal displacement of the stent of 8.4 mm, with the distal end projecting into the base of the aneurysm. Successful coiling was achieved using waffle-cone technique in this patient. Two patients needed a second stent to allow adequate coverage of the neck of the aneurysm. There were no clinical complications.

Conclusion

A majority of patients with wide-neck intracranial aneurysms treated with Enterprise self-expanding intracranial stent have no significant migration. A minority of patients develop migration requiring additional stents or modification in technique for coiling.

Competing interests

None.

Reference

1.Kelly ME, Turner RD, Moskowitz SI,et al.Delayed migration of a self-expanding intracranial microstent.AJNR Am J Neuroradiol2008;29:1959–60.
E-049 Percutaneous embolization of clival dural AVF via foramen ovale
Authors: Urdaneta A , Chen J , Chao K , Feng L
Published: July 2012

Purpose

To evaluate the feasibility of percutaneous embolization of clival dural AVF with difficult venous access.

Materials and Methods

A 69-year-old woman with EF of 15%–20% presented with a 9-month history of progressive right proptosis, chemosis, ophthalmoplegia and visual loss. Angiogram showed a small left clival dural AVF supplied by dural branches of bilateral meningohypophyseal trunks. The recipient vein was in the left dorsal clivus, superior and medial to the Meckel's cave. It drained underneath the posterior clinoid to its counterpart vein on the right side, connecting to a cortical vein and the right superior ophthalmic vein. The right cavernous sinus, right facial vein and bilateral inferior petrosal sinuses were occluded. There was no connection of the fistula to the left cavernous sinus. Transarterial embolization of bilateral meningohypophyseal trunks with Onyx resulted in only partial alleviation of her symptoms. Transvenous embolization was attempted but access to the left clival vein could not be established. Percutaneous embolization was thus planned using CT angiography. A 20 Gauge spinal needle was advanced into the left clival vein via the left foramen ovale under fluoroscopy guidance. The fistula was embolized with Onyx.

Results

Angiographic cure of the dural AVF was immediately achieved. The patient's symptoms improved next day and completely resolved within 2 months. Follow-up angiogram showed durable occlusion of the fistula at 3 months.

Conclusion

Dural AVF in the posterior cavernous sinus and dorsal clivus may be embolized percutaneously via foreman ovale.

Competing interests

None.

Abstract E-049 Figure 1Abstract E-049 Figure 2
E-055 Predictive value of flat panel CT for hemorrhagic transformations in acute stroke patients treated with thrombectomy
Authors: Pistocchi S
Published: July 2012

Background and Purpose

Hemorrhagic transformations are pejorative for patients with acute ischemic stroke (AIS). We evaluated flat panel CT (FPCT) to detect enhancing brain parenchymal lesions immediately after mechanical thrombectomy (MT) in AIS patients and its ability to predict hemorrhagic transformation within 24 h. The second objective was to evaluate an easy-reading protocol for post-procedure FPCT evaluation by clinicians to enable them to determine the potential risk of hemorrhagic transformation.

Material and Methods

Two neuroradiologists retrospectively and independently reviewed FPCT and 24-h follow-up imagery for AIS patients revascularized by MT. We evaluated brain parenchymal enhancement on FPCT and evaluated its power to predict the occurrence of hemorrhagic transformation within 24 h detected with conventional cross sectional imaging (CT, MR) on 63 consecutive patients. κ test was used for inter observer agreement.

Results

We observed a large homogeneity between the different readers (two neuradiologists and one intensivist). Thirty-eight patients were followed at 24 h with conventional non-enhanced CT, 25 patients with MRI. 60.3% of the 63 included patients presented a post procedural parenchymal enhancement and 53.9% had hemorrhagic transformation. 84.2% of patients with enhancement presented hemorrhagic transformation, vs 8.0% of the patients without enhancement (p<0.0001). No significant hemorrhagic transformations were detected on the 24-h follow-up for patients without enhancement. Sensibility and specificity of enhancing parenchymal lesions on FPCT for the prediction of hemorrhagic transformation were respectively 94.1% (80.3–99.3) and 79.3% (60.3–92.0). The positive and negative predictive values for the occurrence of a hemorrhagic transformation were 84.2% (68.8–94.0) and 92% (74.0–99.0). For significant PH2 hemorrhagic transformation, sensibility and negative predictive value of FPCT were 100%.

Conclusions

In the light of our results, FPCT can be deemed as effective as conventional CT scans to predict the risk of 24 h hemorrhagic transformation. FPCT is cost effective and augments patient safety in the setting of MT of AIS patients.

Competing interests

None.
E-057 Embolization of a spinal dural AV fistula after super selective WADA test spinal AV fistula presenting as foot drop: Abstract E-057 Figure 1
Authors: Nduku V , Barrer S , Shah Q , Kozak O , Yoon M , Meagher R , Gopez J
Published: July 2012

Spinal arteriovenous malformations are uncommon lesions that present with a constellation of nonspecific symptoms eluding most clinicians. They comprise 3%–16% of all compressive spinal cord lesions and are attributed to 30% of idiopathic myelopathies. They are most often diagnosed on imaging by a neuroradiologist. They can present with symptoms of myelopathy and radiculopathy mimicking a plethora of pathologies. We report the case of a 79-year-old female who presented with back pain and a left foot drop. MRI suggested edema in the conus medullaris and a spinal angiogram revealed serpiginous enhancement from T11-L1 consistent with a type I AVM (Dural AV fistula). She eventually underwent successful embolization after a super selective WADA test with complete occlusion of the Spinal AV fistula.

Competing interests

None.

Abstract E-057 Figure 1
E-006 Intraprocedural flat panel perfusion scan-immediate reversal of deficit after MCA thrombectomy
Authors: Moser F , Maya M , Moore T , Song S , Pressman B
Published: July 2012

Purpose

Flat Panel Detector CT (FPCT) has shown promise as a tool in treating and assessing acute stroke treatment.1–3We have begun are organized study to compare this modality to standard multislice CT perfusion studies and see if reversal of prediction of outcomes can be derived from these intraprocedural studies. We are reporting our initial experience.

Case

A 58-year-old male was transferred to our institution after being given intravenous t-PA for an acute left middle artery stroke. On admission he was nearly completely recovered from his event with a CTA demonstrating a defect in the left distal M1 segment. On hospital day 2 he developed a profound left-sided weakness. A MSCT perfusion showed a large perfusion deficit in the right MCA territory with an occlusion of the artery on the CTA. He was brought to the angiographic suite and was entered into an IRB approved post marketing study of FPCT perfusion. He underwent an aortic run with the catheter in the very proximal aorta before (Abstract E-006 figure 1) and after (Abstract E-006 figure 2) successful thrombectomy with a 054 Penumbra System.

Abstract E-006 Figure 1Abstract E-006 Figure 2

Results

The FPCT perfusion study demonstrated immediate reversal of the perfusion deficit and the patient recovered. We will present the studies.

Conclusion

Although this is an initial case there was a dramatic change in the perfusion scan and rapid clinical improvement. The study is ongoing.

Competing interests

F Moser: None. M Maya: None. T Moore: Siemens Medical Solutions. S Song: None. B Pressman: None.

References

1.Struffert T, Deuerling-Zheng Y, Kloska S,et al.Flat panel detector CT in the evaluation of brain parenchyma, intracranial vasculature, and cerebral blood volume: a pilot study in patients with acute symptoms of cerebral ischemia.AJNR Am J Neuroradiol2010;31:1462–9.

2.Struffert T, Deuerling-Zheng Y, Engelhorn T,et al.Feasibility of Cerebral Blood Volume Mapping by Flat Panel Detector CT in the Angiography Suite: First Experience in Patients with Acute Middle Cerebral Artery Occlusions. 10.3174/ajnr.A2839.

3.Mordasini P, El-Koussy M, Brekenfeld C,et al.Applicability of tableside flat panel detector CT parenchymal cerebral blood volume measurement in neurovascular interventions: preliminary clinical experience.AJNR2012;33:154–8.