bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation of Changes in Segmental Kinematics and Load Distribution on Components of Lumbosacral Fixation After Addition of Iliac Screw
Authors: Kiapour A. , Kiapour A. M. , Goel V. K.
Published: July 2013

Spinal fusion technique is the common traditional surgical intervention for treatment of various spinal disorders. Long lumbosacral fixation is often recommended for adjustment of lumbar scoliosis [1]. However when extending a long fusion system down to the sacrum, the lumbosacral junction is a common site of implant problem and pseudarthrosis [2,3].
Prediction of Knee Loads Using a Lower Extremity Model Based on the Klein Horsman Data Set
Authors: Schwartz Cédric , Lund Morten Enemark , de Zee Mark , Rasmussen John
Published: July 2013

In this paper, the in-vivo loads of the knee joint provided by an instrumented prosthesis (Fregly et al., 2010, Lin et al., 2010, Kim et al., 2009) are compared to the results obtained from an implementation of the Klein Horsman data set (2007) in the AnyBody Modeling System. The lateral and medial knee contact forces are estimated directly from the knee modeled as a modified revolute joint. As such, this study presents what can be achieved by estimating the knee contact forces from a simplified knee model.
Characterization of Al2O3/GaAs interfaces and thin films prepared by atomic layer deposition
Authors: Sah Ram Ekwal , Tegenkamp Christoph , Baeumler Martina , Bernhardt Frank , Driad Rachid , Mikulla Michael , Ambacher Oliver
Published: July 2013

Characterization of GaAs/Al2O3 interfaces and thin (∼1–10 nm) Al2O3 films prepared by atomic layer deposition (ALD) is performed using variable angle spectroscopic ellipsometry (SE), x-ray photoelectron spectrometry (XPS), and stress measurements. The SE measurements reveal the presence in all samples of an interfacial layer around 1 nm-thick, though the layer originating from thermal ALD is slightly thinner than those from plasma ALD. The refractive index of the interfacial layer is found to be higher than that of a stoichiometric Al2O3 film. The XPS measurements reveal higher O:Al ratios in films thinner than 4 nm, due to fact that the XPS technique probes oxygen in both the stoichiometric Al2O3 films and the interfacial layers, because the mean free path length of the O1s photoelectrons is 4 nm. The perfectly symmetric Al signal in the XPS measurements suggests the absence of Al suboxides. The temperature cycle dependence of residual stress in the film reveals slightly different paths for the heating and cooling half cycles. The coefficient of thermal expansion is found to be much higher for thin films than thicker (∼70 nm) films, which is attributed to the relatively large contribution of the interfacial layer to residual stress in the thin films.
Level dominance for the detection of changes in level distribution in sound streams
Authors: Richards Virginia M. , Shen Yi , Chubb Charles
Published: July 2013

Sound streams were generated by randomly choosing the levels of tone pips from two different distributions, A and B. Of the 18 tone pips, the first nine were drawn from distribution A and the second nine from distribution B, or the opposite. The listeners' task was to indicate order, A-B or B-A. In two conditions the A and B distributions differed in mean (condition 1) or variance (condition 2). In contrast to an ideal observer, listeners' strategies were consistent across the two conditions. Analyses suggest that listeners relied primarily on the more intense tone pips in making their decisions.
Passive estimation of the waveguide invariant per pair of modes
Authors: Le Gall Yann , Bonnel Julien
Published: July 2013

In many oceanic waveguides, acoustic propagation is characterized by a parameter called waveguide invariant. This property is used in many passive and active sonar applications where knowledge of the waveguide invariant value is required. The waveguide invariant is classically considered as scalar but several studies show that it is better modeled by a distribution because of its dependence on frequency and mode pairs. This paper presents a new method for estimating the waveguide invariant distribution. Using the noise radiated by a distant ship and a single hydrophone, the proposed methodology allows estimating the waveguide invariant for each pair of modes in shallow water. Performance is evaluated on simulated data.
When intelligibilities of paired speech bands do not behave the way they are supposed to
Authors: Warren Richard M. , Bashford James A. , Lenz Peter W.
Published: July 2013

Two rectangular 1/3-octave passbands were derived from different spectral regions of everyday sentences, with the intelligibility of one band approximately twice the others. Both passbands were then filtered to produce a series of narrower rectangular passbands. Each of the original 1/3-octave passbands in turn served as the fixed bandwidth “pedestal” and was paired with each of the series of narrower passbands of the other band. Remarkably, dual band intelligibilities were the same, regardless of which band served as pedestal, so the summed bandwidths determined intelligibility: The summed intelligibilities were irrelevant. Implications of this paradoxical “summed bandwidth rule” are discussed.
O-010 The Barrow Neurological Institute Experience with the Pipeline Embolisation Device: Results in the First 100 Patients Treated after FDA Approval
Authors: Albuquerque F , Ducruet A , Crowley W , McDougall C
Published: July 2013

Aims and Objectives

The Pipeline Embolisation Device (PED) was recently approved in the United States (US) for the treatment of wide-necked anterior circulation aneurysms. Studies in both the US and Europe have confirmed its efficacy as well as an acceptable complication rate associated with its use. In this setting, we sought to analyse our results prospectively in the first 100 patients treated at our institution since FDA approval of the device in May of 2011.

Materials and Methods

We analysed all patients treated with the PED, specifically assessing the following factors: patient demographics, number of devices used, aneurysm location, clinical/angiographic follow-up, rate of obliteration, number of residual aneurysms, and complications.

Results and Discussion

100 patients with 115 aneurysms were treated with the PED. Of these, there were 19 men and 81 women ranging in age from 23 to 83 years (mean = 59.2 years). A total of 185 PEDs were used with an average of 1.85 per patient. Aneurysm locations were myriad with the peri-ophthalmic and cavernous segments comprising the largest proportion (35 and 33 aneurysms respectively). Fourteen posterior circulation aneurysms were treated in this cohort. Radiographic follow-up was obtained in 68 patients at an average of 6.6 months after treatment. Of these, 45 patients demonstrated complete obliteration of their aneurysms and 12 patients near-complete (< 90%). The rate of complete and near-complete obliteration was 83.8%. A total of 20 complications occurred with 3 of these being permanent and 17 transient. The 3 permanent complications included 2 deaths and 1 stroke. Patient compliance with and/or tolerance of anti-platelet therapy was a major factor accounting for complications. The overall rate of permanent complications was 3%.

Conclusions

The PED is a safe and effective means of treating complex cerebral aneurysms. Nonetheless, a number of technical factors and patient compliance issues complicate its use.

Disclosures

F. Albuquerque: None. A. Ducruet: None. W. Crowley: None. C. McDougall: None.
E-042 Case Based Review of the Pathophysiology of Internal Carotid Artery Pseudoaneurysm Coil Migration
Authors: Morgan R , Best S , Connor C , Madarang J , Johnson P
Published: July 2013

Learning Objectives

Review the pathophysiology and risk factors of internal carotid artery (ICA) pseudoaneurysm formation.

Evaluate imaging of coil migration following endovascular treatment of internal carotid artery pseudoaneurysm.

Discuss treatment options of coil migration.

Background

Pseudoaneurysm results from disruption of one or more layers of the arterial wall, which results in blood dissecting into the surrounding tissues. The formation of ICA pseudoaneurysm is a known complication related to radiation therapy and arterial injury during surgery. Endovascular coil embolisation has been proven an effective treatment for ICA pseudoaneurysm, however one of the rare complications is coil migration.

Clinical Findings/Procedure Details

Two patients with history of iatrogenic ICA injury during tumour resection subsequently developed pseudoaneurysms. Both were initially treated with endovascular coil embolisation and both went on to suffer migration and prolapse of the coil into the pharynx. In both cases the coil mass demonstrated migration with erosion through the pseudoaneurysm wall. The first patient underwent coil embolisation 20 years prior to presenting with globus sensation and epistaxis. The second patient, who had previously been treated with radiation, developed transmucosal coil migration 1 month after embolisation. In both cases the complications associated with coil migration were fatal.

Conclusion and/or Teaching Points

When treating ICA pseudoaneurysm with coil embolisation there are multiple factors which can increase the risk of coil migration. While it is rare coil migration is a known complication of endovascular embolisation which can occur months to decades after the initial procedure.

Disclosures

R. Morgan: None. S. Best: None. C. Connor: None. J. Madarang: None. P. Johnson: None.
E-044 The Penumbra 5MAX, 4MAX and 3MAX Reperfusion Catheters in Treatment of Acute Ischaemic Stroke: Initial Clinical Experience
Authors: Farkas J , Arcot K , Walzman D , Kumar R , Delbrune J , Papamitsakis N , Margulis Y , Dash S , Levin K , Azhar S
Published: July 2013

Introduction/Purpose

The new material composition and larger, tapered lumen in the distal end of the novel Penumbra MAX System reperfusion catheters are designed to enhance aspiration efficiency with improved trackability. Reported herein are results from a retrospective multicentre study with the Penumbra System 5MAX, 4MAX and 3MAX reperfusion catheters in the treatment of acute ischaemic stroke secondary to large vessel occlusion.

Materials and Methods

A retrospective case-review of 19 consecutive acute ischaemic stroke cases treated with the Penumbra System either as a standalone device or in combination: 5MAX (n=8), 4MAX (n=6) and 3MAX (n=8), from July 2012 through December 2012 was undertaken. Clinical experience at 3 institutions was collected and reported in the first six months after device release. Occlusions were located in the MCA M1and M2 (n=11), ICA and ICA/MCA (n=6), and vertebrobasilar arteries (n=2).

Results

Eighteen of 19 cases (94.7%) were successfully recanalised to TICI 2 and 3 using the Penumbra MAX System. Complete revascularisation to TICI 3 was achieved in 16 of 19 (84%). The mean patient age was 70.3 ± 13.9 years; the median NIHSS score at presentation was 19 (15 to 29). All patients presented with TICI scores of 0 or 1. At discharge, the median NIHSS score was 14 (1 to 29). One death due to cardiac arrest occurred at 15 days post-procedure. In one patient, stroke in a new territory was observed and treated with IA rtPA. One ICH was found in a previously unaffected region, possibly secondary to IV rtPA therapy.

Conclusion

Early multicentre experience indicates that the 5MAX, 4MAX and 3MAX reperfusion catheters have enhanced aspiration efficiency and trackability. Follow-up studies will be required to verify these findings.

Disclosures

J. Farkas: None. K. Arcot: None. D. Walzman: None. R. Kumar: None. J. Delbrune: None. N. Papamitsakis: None. Y. Margulis: None. S. Dash: None. K. Levin: None. S. Azhar: None.
E-049 In-Vitro Testing Of Stents Dedicated For The Carotid Arteries
Authors: Wissgott C , Schmidt W , Behrens P , Schmitz K , Andresen R
Published: July 2013

Objective

The design and material determine the mechanical properties of stents and implant behaviour during the intervention. In vitro parameters such as radial force, flexibility and wall adaptation of different stents were investigated in order to obtain evidence for clinical use.

Material and Methods

A total of 8 current stent systems (Sinus Carotid RX, Cristallo Ideale, Adapt, Carotid Wallstent, Vivexx Carotid Stent, Xact Carotid Stent, Protégé Rx and Precise) with a diameter of 8 mm and a length of 40 mm, which are authorised for the treatment of carotid stenoses, were investigated. The radial force on expansion as a function of the diameter, the flexural rigidity of the stent system and of the stent in its expanded state, as well as the collapse pressure in a thin, flexible sleeve were measured. The wall adjustment of the expanded stents was documented by fluoroscopy after release in a step and curve model and assessed.

Results

The flexural rigidity of the stent systems declined significantly in the expanded state, whereby the Xact Carotid stent showed the highest value (291.1 Nmm2) in contrast to 31.6 to 39.0 Nmm2for the Sinus Carotid and Cristallo Ideale. The radial force on expansion of the stents to 7 mm was lowest in the Adapt (0.009 N/mm) and highest in the Precise (0.068 N/mm), while the hybrid stents achieved values of between 0.027 and 0.046 N/mm. The collapse pressure was highest in the Carotid Wallstent as a result of its particular stent structure (0.48 bar), compared with the other stents (0.1 - 0.2 bar). The best wall adjustment in the curve model was shown by the Precise, the Sinus Carotid Rx and the Vivexx Carotid Stent. The diameter change from 5 to 7 mm was smoothly adapted by Cristallo Ideale and Carotid Wall Stent. The extraordinary design of the Adapt showed poor vessel wall adaptation both in step and curved vessels.

Conclusion

As a result of their design, the Sinus Carotid Rx and the Cristallo Ideale in the “hybrid design” show the best wall adjustment, with comparable radial force and high flexibility, and thus can also be used in the case of an axis-deviant vascular course with variations in vessel diameter, whereby the Cristallo Ideale has the advantage that it has a “closed-cell” design in the middle third of the stent. In the event of unusual vascular anatomies, the other stents should be taken into consideration with their specifications in individual cases.

Disclosures

C. Wissgott: None. W. Schmidt: None. P. Behrens: None. K. Schmitz: None. R. Andresen: None.
E-055 Ethanol and Coil Embolisation of Complex Dural Arteriovenous Fistula
Authors: Yakes W
Published: July 2013

Introduction

To evaluate the efficacy of ethanol, as well as ethanol and coils, in the management of complex dural AVF.

Methods

Fifteen patients (mean age 39 years; 10 females, 5 males). All patients presented with dural AVF involving the transverse sinus, sigmoid sinus and cavernous sinus. One patient suffered from high output cardiac state due to the massive size of her combined dural fistula and scalp AVM. All patients underwent MR and cerebral arteriogram evaluations. Patients underwent ethanol embolisation, coil embolisation or ethanol and coil embolisation in combination. These acquired AVF were non-traumatic.

Results

All fifteen patients were endovascularly cured of their disease at a mean follow-up of five months. One patient’s therapy is on-going. In those patients who had thrombosed sigmoid sinuses and partially thrombosed transverse sinuses with critical venous drainage due to the occluded sinuses, novel endovascular approaches were utilised to reach the point of fistualisation and treat with coils and ethanol. Sacrifice of the diseased transverse and sigmoid sinus were also utilised to treat the large dural AVFs involving these segments. In the cavernous sinus only coil embolisation and nBCA embolic agents were utilised. In those patients presenting the pulsatile tinnitus, it was absent at follow-up. Headaches and all other symptoms were resolved. Except for one patient with a transient homonymous hemianopsia, no other complication occurred.

Conclusion

Complex acquired dural AVF can be treated by endovascular means. With meticulous technique complications can be avoided. Long-term cures have been documented with retrograde approaches within the dural sinuses using ethanol, coils, and at times nBCA. By this venous approach complications can be vastly diminished.

Disclosures

W. Yakes: None.
E-057 Risk factors influencing duration of Cerebral Angiography: A single centre study.
Authors: Malhotra K , Schramke C , Ku A
Published: July 2013

Introduction/Purpose

Cerebral angiography is an invasive procedure used for diagnostic and therapeutic purposes in cerebral atherosclerotic diseases. Prolonged duration of procedures has been linked with higher likelihood of complications. A better understanding of the factors that influence procedure duration is required to enhance patient safety, as they have important implications for both reimbursements and patient care.

Materials and Methods

Data were retrospectively collected over a two month period for a cohort of patients undergoing diagnostic cerebral angiography at our centre. Medical charts were reviewed and data were collected for patients regarding diagnoses of hypertension, hyperlipidaemia, diabetes, and tobacco abuse. We also recorded age, gender, weight and height for calculation of Body Mass Index (BMI), number of vessels studied, and procedure start and end time.

Regression analysis was used to determine the factors that were most strongly associated with the duration of procedure. The variables included in this analysis were hypertension, hyperlipidaemia, diabetes, tobacco abuse, age, BMI>30, and the total number of vessels studied during the procedure. We also looked at correlation of total number of risk factors (hypertension, hyperlipidaemia, diabetes, tobacco abuse, BMI>30, and age>65) with the procedure duration in each patient.

Results

A total of 38 charts including 22 females and 16 males were identified and reviewed. The age of our patients ranged from 27 to 88 years with mean age 56.76 years, S.D = 14.2. Frequencies of various risk factors for the total sample were: hypertension (60%), hyperlipidaemia (45%), diabetes (9%), tobacco abuse (42%), BMI >30 (32%) and age>65 (26%). Using stepwise regression, we found that BMI>30 (p=0.010) and then age (p=0.021) were the strongest predictors of procedure length, and both in combination accounted for 30% of the total variance (p=.003). Correlational analysis showed a significant relationship between total number of risk factors and procedure duration (r=0.57, p=0.001). Surprisingly, total number of vessels studied during each procedure did not correlate with the procedure time (r= -0.043, p=.80).

Conclusion

Patient characteristics such as BMI and age are associated with prolonged duration of procedures. These risk factors does play an important role in the patient care and hence with the reimbursements of such procedures. Further large prospective studies are required to corroborate with our findings.

Disclosures

K. Malhotra: None. C. Schramke: None. A. Ku: None.
E-061 Onyx Embolisation Through the Scepter Dual-Lumen System: Mechanisms and Utility
Authors: Chung C , Osanai T , Hui F
Published: July 2013

Introduction

Ethyl Vinyl Alcohol co-polymer Onyx (ev3 Inc., Irvine, CA) is a non-adhesive but cohesive liquid embolic agent that can be used to occlude vascular lesions. On label indications are for arteriovenous malformations, but the fluid has been useful in a variety of clinical scenarios including dural arteriovenous fistulae (dAVF), aneurysms, tumour embolisation and others. The key drawbacks of these techniques are in the time, material, and radiation needed for the formation of a proximal plug to force the flow of Onyx forward into the vascular territory, as well as the possibility of difficult catheter removal. The usage of Oynx in conjunction with the Scepter C dual lumen coaxial balloon system (MicroVention, Tustin, CA) can circumvent the need for plug formation and avoid associated drawbacks.

Materials and Methods

The endovascular database at a single institution was reviewed to assess for cases in which ethyl vinyl alcohol was used in conjunction with a Scepter C balloon. In each case, the Scepter C balloon was navigated to the target artery under fluoroscopic roadmap assistance. The balloon was inflated to occlude the vessel, and the lumen was flushed with DMSO. Onyx 18 embolisation was subsequently performed under continuous fluoroscopy until stasis was observed. The cases are reviewed and summarised with attention to fluoroscopy time between the initiation of ethyl vinyl alcohol embolisation and the cessation of ethyl vinyl alcohol embolisation.

Results

Five consecutive patients were treated with a combination of ethyl vinyl alcohol and the Scepter C balloon. In the three tumour cases, a total of six pedicles were embolised; in the dural fistulae cases, two pedicles were embolised. No immediate per-procedural complications occurred. Total fluoroscopy time, average fluoroscopy time per injection, and total time between initial injection and cessation of embolisation are accessed and compared to historical data on Onyx-only embolisation procedures. In a single case, reflux occurred secondary to a loose valve that led to an unplanned balloon deflation.

Conclusion

The Scepter C balloon may be used off-label to deliver ethyl vinyl alcohol for the treatment of dAVF and tumour embolisation. Diminished fluoroscopy times and embolysate injection times may be achieved using an in-line balloon that results in an immediate block to retrograde flow, obviating the need to form a proximal “plug”. Further research is necessary to confirm safety and radiation exposure benefits, especially in arteriovenous malformations.

Disclosures

C. Chung: None. T. Osanai: None. F. Hui: 3; C; MicroVention, Penumbra.
E-067 Permeability Surface Product as a Predictor of Haemorrhagic Transformation in Acute Ischaemic Stroke Intervention
Authors: Matthews A , Parker M , Rutledge N , Conrad K , Luci J , Bluett B
Published: July 2013

Introduction/Purpose

A significant complication in the intervention of acute ischaemic stroke is haemorrhagic transformation. It has been postulated that perfusion permeability imaging showing increased blood brain barrier permeability can be used to predict haemorrhagic transformation and possibly alter therapies.

Materials and Methods

We retrospectively reviewed 60 CT perfusion scans with permeability surface area product maps calculated using the Patlak model where IV tPA or endovascular thrombectomy was performed at our institution in 2012.

Results

Permeability maps were positive in 31 of the 60 cases. The size of the permeability change was medium to large in 29 of 31 cases (94%). Of the positive permeability cases only two (6%) subsequently developed haemorrhagic transformation (HT). One was a PH2 haemorrhage and one a HI2 haemorrhage. Both cases where HT occurred were successful (TICI 2b/3) endovascular thrombectomies. Neither of these cases developed malignant oedema, required hemicraniotomy or other intervention. No difference was found in the size or degree of the permeability changes and the incidence of HT.

Conclusion

Elevated permeability on CT perfusion imaging had no relevant predictive value for haemorrhagic transformation in acute ischaemic stroke interventions at our institution.

Disclosures

A. Matthews: None. M. Parker: None. N. Rutledge: None. K. Conrad: None. J. Luci: None. B. Bluett: None.
O-013 Intra-aneurysmal Flow Disruption: a New Approach for the Endovascular Treatment of Intracranial Aneurysms. French Clinical Experience
Authors: Pierot L , Januel A , Raoult H , Spelle L , Papagiannaki C , Desal H , Courtheoux P , Kadziolka K. Krzysztof , Gauvrit J , Moret J , Herbreteau D , Cognard C
Published: July 2013

Purpose

Standard coiling is now the first line approach for the treatment of intracranial aneurysms. However, this technique has some limitations, including treatment of wide-neck and large and giant aneurysms and recanalisations. Therefore, new techniques and devices are needed. The objective of intra-saccular flow disruption is the modification of aneurysmal flow by placing a device in the aneurysm sac. Preliminary clinical experience in French centres is presented.

Materials and Methods

Computational fluid dynamics and pre-clinical testing (canine cross-over carotid bifurcation model) were used to develop an intra-saccular flow disrupter design, designated as WEB (Sequent, Aliso Viejo, CA).The WEB is a self-expanding, oblate, braided nitinol mesh, composed of an inner and outer braid held together by proximal, middle, and distal radio-opaque markers and creating two compartments: one distal and one proximal.Clinically, 39 patients (27F/12M, age: 37–75 years) harbouring ruptured, unruptured or recanalised aneurysms were treated between June 2011 and January 2013 in 7 French centres, using an intra-aneurysmal flow-disrupter (WEB).

Aneurysm location was middle cerebral artery (23 aneurysms), basilar artery (8), internal carotid artery (5), and anterior communicating artery (3). Aneurysm size was 10mm in 5 aneurysms. Neck size was > 4mm in 5 aneurysms and <4mm in 35 cases.

Results

Clinically, the device was successfully deployed in all but 2 cases. Three thromboembolic events were observed with favourable outcome in both cases (mRS ≤2). No intraoperative rupture was observed. No delayed rupture or remote haematoma was observed. Additional coiling was performed in 4 cases. Mid-term follow-up results are presented.

Conclusion

Intra-saccular flow disruption using WEB is a completely new endovascular approach to treat some types of aneurysm, particularly wide-neck bifurcation aneurysms. This preliminary clinical experience shows the safety and efficacy of the device when used in appropriately selected cases.

Disclosures

L. Pierot: 2; C; Sequent. A. Januel: None. H. Raoult: None. L. Spelle: None. C. Papagiannaki: None. H. Desal: None. P. Courtheoux: None. K. Krzysztof Kadziolka1: None. J. Gauvrit: None. J. Moret: None. D. Herbreteau: None. C. Cognard: None.
E-074 Pipeline Strategies
Authors: Urdaneta A , Darflinger R , Chao K , Feng L
Published: July 2013

Background

Pipeline Embolisation Device (PED) is a flow diversion stent for the treatment of large wide neck aneurysms that are not well treated with coiling methods including stent assisting coiling. The PED material and design are relatively unique including its deployment.

Objective

Evaluation of the PED procedures including issues during deployment and strategies to outcome problems.

Methods

Retrospective multicentreed case series of 30 PED procedures for treatment of aneurysms. The cases were evaluated for issues that arose during PED deployment. The different strategies for managing problems was assessed for their effectiveness.

Results

There were eight major issues with PED deployment. 1. Detachment from capture coil, 2. PED apposition to the vessel wall, 3. Torqueing or twisting of the PED, 4. Accurate placement of the PED, 5. Herniation of PED into aneurysm, 6. Advancing the microcatheter and removing the delivery system, 7. Accessing the distal outflow artery, and 8. Post procedure stroke within 3 days. Successful treatment strategies for each of the major issues demonstrated reasonable success.

Conclusion

PED is a 1st generation flow diversion stent with a variety of issues related to its deployment. However, familiarity with PED deployment strategies can result in a more successful deployment.

Disclosures

A. Urdaneta: None. R. Darflinger: None. K. Chao: None. L. Feng: None.
E-080 Outcomes of Carotid Artery Angioplasty and Stenting in Patients after Treatment of Acute Ischaemic Stroke
Authors: Morone P , Mocco J
Published: July 2013

Introduction and Purpose

Internal carotid artery (ICA) angioplasty and stenting is a possible treatment modality for patients with acute stroke that is associated with carotid artery occlusion. Here we investigate the use of this combined technique and evaluate the results and outcomes of carotid artery recanalisation in patients presenting with acute ischaemic stroke.

Methods

Over a period of six months, five patients with acute ischaemic stroke associated with cervical ICA occlusion underwent combined ICA angioplasty and stenting. A retrospective review was completed and clinical variables were measured and evaluated. Thrombolysis in cerebral ischaemia (TICI) score was used to define the degree of recanalisation, and a favourable outcome was defined as a Modified Rankin Scale (mRS) score of 0–3 at 90 days.

Results

The mean patient age was 60.2 (range49–77) and the mean presenting National Institute of Health Stroke Scale was 17.8 (range16–19). Out of all patients, four had complete occlusion of the left ICA and one had complete occlusion of the right ICA. In four patients there was concomitant intracranial occlusion. The time from symptom onset to endovascular intervention was ≤ 3 hours in three patients, 10 hours in one patient and unknown in the other patient. Internal carotid angioplasty with stenting was completed in all patients. A TICI score greater than IIb was achieved in 100% of patients and grade III was achieved in 60% of patients. The 90 day mRS was 0–2 in 40% of patients and 0–3 in 80% of patients.

Conclusion

Clinical outcomes suggest that carotid artery angioplasty when combined with stenting is a useful and reasonable technique for carotid artery recanalisation in patients undergoing an ischaemic stroke. Further studies need to be completed to assess the overall safety and efficacy of this combined technique for use of treatment in acute ischaemic stroke.

Disclosures

P. Morone: None. J. Mocco: None.
O-016 Treatment of Intracranial Aneurysms with the LUNA AES Updated
Authors: Piotin M , Biondi A , Sourour N , Mounayer C , Andersson T , Söderman M , Mangiafico S , Jaworski M , Anxionnat R , Blanc R
Published: July 2013

Purpose

The LUNA Aneurysm Embolisation System (AES) is a new self-expanding ovoid device that serves as an intra saccular flow diverter as well as a scaffold for endothelisation across the neck. The objective of this prospective clinical study aiming to include a total of 63 patients was to evaluate the ability of the AES to occlude intracranial aneurysms while maintaining patency of the parent artery.

Materials and Methods

Immediate post-implantation occlusion grade (complete obliteration of the aneurysm including the neck), near-complete (persistence of any portion of the original defect of the arterial wall), or incomplete (any opacification of the sac) compared to baseline), and parent vessel compromise were evaluated. Patients underwent neurological testing with the Modified Rankin Scale and the National Institute of Health Stroke Scale (NIHSS) at baseline and time of discharge. Follow-up included clinical assessment at one, 3, 6, 9 and 12 months, and angiographic follow-up at 6 and 12 months.

Results

50 patients (9 men) with 47 unruptured and 4 ruptured saccular aneurysms (38 bifurcation, 13 sidewall, sizes from 3.9 to 10.1 mm) were enrolled to date in the study. In all but 2 aneurysms (2 failed procedure converted in coiling) 1 LUNA AES was deployed per aneurysm. In 5 cases, the LUNA AES placement was carried out with balloon microcatheter assistance. In one case, the LUNA AES placement was carried out with a stent. In 1 case, AES placement led to aneurysm perforation that was controlled by temporary balloon occlusion and heparin reversion. In 1 case, thrombo-embolic complication was treated with i.a. injection of Abciximab. Clinical follow up was uneventful in all but 2 patients (one sustained SAH from a contralateral MCA aneurysm, one had GI bleeding). Immediate complete/near complete occlusion was obtained in 22.5% (22/49). At 6 month follow-up, complete/near complete occlusion was obtained in 70.4% (19/27). There was no parent artery stenosis or occlusion. None of the treated aneurysm (re)bled during follow-up.

Conclusion

Preliminary results demonstrate good safety profile. Angiographic follow up are promising with no recanalisation.

Disclosures

M. Piotin: None. A. Biondi: None. N. Sourour: None. C. Mounayer: None. T. Andersson: None. M. Söderman: None. S. Mangiafico: None. M. Jaworski: None. R. Anxionnat: None. R. Blanc: None.
O-020 Head and Neck Endovascular Repair of Vascular Malformations
Authors: Yakes W
Published: July 2013

Objective

To determine the efficacy of ethanol embolotherapy of extracranial head and neck vascular malformations of all types, particularly after failure of other endovascular and surgical treatments.

Methods

One hundred and sixty-six patients (64 males, 102 females; mean age: 38 yrs) presented with extracranial arteriovenous malformations (AVMs) of the head and neck area. Over half of the patients had undergone previous failed therapies. All patients underwent ethanol embolotherapy under general anaesthesia. Forty-five patients had AVMs and 121 patients had venous malformations (VM).

Results

Of 45 AVM patients, 26 patients are cured (mean follow-up 2½ years); of 121 venous malformation patients, 65 are at end-therapy (mean follow-up 4½ years). The remaining patients are not at end-therapy and are being treated for their residual malformations. In AVM follow-up, arteriography is the main imaging modality to determine cure or residual AVM as MR is less sensitive in the evaluation of residual AVM. In VM follow-up, MR is the main imaging tool, particularly with T-2 fat suppression and/or STIR imaging. All patients demonstrated improvement post-therapy. Complications were 4.5%, to include bleeding (self-limited), partial 7th nerve palsy (with recovery), skin injury (not requiring skin grafts), infection, and pain.

Conclusions

Ethanol has proven its consistent curative potential at long-term follow-up for high-flow AVMs and low-flow VM lesions at long-term follow-up as lesions in the periphery. Complication rates remain low. The procedures are tolerated well by the patients and done on an out-patient basis. Prior surgery and embolisation procedures can cause difficulty in lesion access, but does not obviate further ethanol endovascular treatment.

Disclosures

W. Yakes: None.
P-001 Initial Multicentre Clinical Experience with Treating Small Aneurysms (<5mm) with the Penumbra PC400 Large Volume Coil: Improving the Treatment of Small Aneurysms at 4 High Volume US Centres
Authors: Baxter B , Quarfordt S , Patel A , Moyle H , Turk A , Chaudry I , Turner R , Frei D , Huddle D , Bellon R
Published: July 2013

Introduction/Purpose

We report clinical experience and long-term follow-up results in treating 24 small aneurysms in 22 patients, ranging from 2mm to 4.4mm, using the Penumbra PC400 Large Volume Coil at 4 high volume centres. Follow-ups are available for 12 aneurysms at the current time.

Materials and Methods

Our treatment population consisted of 24 aneurysms ranging between 2 mm and 4.4 mm as measured by maximal aneurysm dimension, treated between February 2011 and September 2012. Seven were ruptured and 17 unruptured. Aneurysm location was 19 in the anterior circulation and 5 in the posterior circulation.

Results

The average aneurysm size was 3.5 mm, with 52% average packing density. All aneurysms were treated entirely with PC400 coils, several with only 1 coil each. Fifty percent (50%) of the cases achieved an initial Raymond Scale of 1, 21% achieved a Raymond scale of 2, and 29% were Raymond Scale of 3. Half (12) of the aneurysms have angiographic follow-up at the time of this abstract. Based on the same/better/worse scale, 100% of aneurysms showed stable or improved angiographic outcomes at 6 months and one year. Seven had improved occlusion rating, and all the rest remained unchanged. We experienced a 0% overall rate of morbidity and mortality. One SAH patient had a thromboembolic event with no clinical sequelae, and 2 aneurysms had coil loop prolapse with no clinical sequelae, both patients being discharged with mRS 0. We continue to use the coils and accrue follow up and will update results at the time of the meeting.

Conclusion

Our clinical experience with the PC400 Coil system has demonstrated this .020" coil and 025 ID deployment catheter to be safe and efficacious in treating small aneurysms. Use of the PC400 Large Volume Coil results in high packing densities and high rates of occlusion on follow-up. The softness profile of this large volume coil can allow treatment of small aneurysms in some cases with only 1 coil, and the improved body of the deployment catheter has markedly improved the treatment of small aneurysms and perhaps made it safer.

Disclosures

B. Baxter: 3; C; Penumbra, Inc. S. Quarfordt: None. A. Patel: 3; C; Penumbra, Inc. H. Moyle: None. A. Turk: 3; C; Penumbra, Inc. I. Chaudry: 3; C; Penumbra, Inc. R. Turner: None. D. Frei: 3; C; Penumbra, Inc. D. Huddle: None. R. Bellon: None.
P-002 The Two Catheter Technique in Comparison to Stent-Assisted Coil Embolisation in the Endovascular Treatment of Intracranial Aneurysms
Authors: Gaughen J , Durst C , Geraghty S , DeMartini N , Kreitel D , Medel R , Patrie J , Jensen M , Evans A
Published: July 2013

Introduction/Purpose

Scientific data currently demonstrates the superiority of coil embolisation over open surgical clipping for the treatment of intracranial aneurysms. As technological advancements continue within the endovascular arena, these endovascular outcomes are expected to improve. Adjunct measures such as balloon remodelling and stent-assistance are increasing the percentage of intracranial aneurysms that can be treated endovascularly, and data is actively being collected to better understand the safety and efficacy of these adjunct modalities. The two catheter technique of endovascular aneurysm treatment is a competitive treatment strategies to these adjunct methods that involves the simultaneous deployment of coils through two catheters placed in an intracranial aneurysm sac for treatment of wide-necked aneurysms. This study evaluates the safety and efficacy of the two catheter technique in comparison to stent-assisted coil embolisation in the endovascular treatment of intracranial aneurysms.

Methods

A retrospective chart review identified 110 consecutive aneurysms which were embolised using the two catheter technique and 101 consecutive aneurysms treated by stent assisted coil embolisation. Patient demographics, details of treatments, effects of treatments, results of follow up procedures, and complications were recorded. Comparison of the two catheter and stent groups was performed using Fisher’s exact test.

Results

The technical success rates between the two-catheter and stent groups were similar at 91% and 95%, respectively. Primary occlusion rates were also similar at 14% for the two-catheter technique and 16% for stent-assisted embolisation. An additional 38% and 39%, respectively, had only neck remnants. As might be expected, recanalisation rates were slightly higher in the two catheter group, 25% vs 16%, though this was not statistically significant (p=0.141). This did not result in a statistically significant increase in the number of retreatments. Permanent morbidity was lower in the two catheter group, 7% vs 11%; however, this was not statistically significant (p=0.108).

Conclusion

The two catheter technique appears to be as safe and effective as stent-assisted coil embolisation in the endovascular treatment of intracranial aneurysms. Although not statistically significant, the treatment trended towards lower permanent morbidity.

Disclosures

J. Gaughen: 2; C; Covidien. C. Durst: None. S. Geraghty: None. N. DeMartini: None. D. Kreitel: None. R. Medel: None. J. Patrie: None. M. Jensen: 2; C; Covidien, Microvention, Stryker. A. Evans: 2; C; Covidien, Microvention.
P-006 Safety and Efficacy of Endovascular Treatment of Paraophthalmic Internal Carotid Artery Aneurysms
Authors: Gaughen J , Durst C , Nguyen Q , Patrie J , Jensen M , Evans A
Published: July 2013

Introduction/Purpose

Within the literature, controversy exists regarding the optimal treatment of ophthalmic segment internal carotid artery aneurysms. The close proximity of the ophthalmic artery and optic nerve increase the complexity of the disease, and the adjacent clinoid process impedes surgical exposure. This study investigates the safety and efficacy of coil embolisation for the treatment of paraophthalmic internal carotid artery aneurysms.

Method

A retrospective chart review identified 79 consecutive aneurysms who presented for elective treatment of an ophthalmic artery aneurysm. Patient demographics, details of treatments, effects of treatments, results of follow up procedures, and complications were recorded. Odds ratios were used to measure the effect size. The McNemar Test for systematic discordance was used to test the likelihood of visual improvement or degradation.

Results

Primary occlusion rate was 44%. The recurrence rate was 33%. In patients with at least 12 months follow-up, the size of the aneurysm (p=0.016), the size of the aneurysm neck (p=0.028), and hypertension (p=0.03) were predictive of the likelihood of recurrence. There were 3 major complications (4%). The average size of the aneurysm was greater in patients who experienced a major complication, though this did not reach statistical significance due to the low number of complications. 28 (35%) of the 79 patients presented with a visual disturbance that could be attributed to the aneurysm. Visual disturbances were experienced in those patients with larger aneurysms, though this was not statistically significant (p=0.285). Of the 28 patients with visual disturbance, 46% experienced improvement in their symptoms while none of the 51 patients who presented without visual disturbances developed a visual field defect postoperatively (p > 0.001).

Conclusion

Endovascular treatment of paraophthalmic internal carotid artery aneurysms appears to be a safe and effective treatment. Major complication rates were found to reside well within the expected rates for intracranial aneurysm treatment. Clinically, almost half of the patients who present with symptomatic visual disturbance or eye pain had significant improvement after treatment, and none of the patients presenting without visual disturbance demonstrated postoperative visual impairment.

Disclosures

J. Gaughen: 2; C; Covidien. C. Durst: None. Q. Nguyen: None. J. Patrie: None. M. Jensen: 2; C; Covidien, Microvention, Stryker. A. Evans: 2; C; Covidien, Microvention.
P-015 High Resolution- MRI Features of Reversible Cerebral Vasoconstriction Syndrome Over Time
Authors: Cerejo R , Hui F , Jones S , Obusez E , Hammad T , Hajj-ali R , Uchino K
Published: July 2013

Introduction

Reversible Cerebral Vasoconstriction Syndrome (RCVS) is associated with thunderclap headache, subarachnoid haemorrhage and potential ischaemic sequelae, with very different management than traditional central nervous system vasculitides. The advent of vessel wall imaging may help differentiate RCVS from other lesions, however knowledge of the imaging features of the syndrome over time may help physicians make the diagnosis with greater confidence.

Methods

The Cleveland Clinic 3-Tesla High resolution MRI (HRMR) database was retrospectively reviewed to identify patients with clinically diagnosed RCVS that also received HRMR yielding a total of 13 patients. Imaging protocol included black-blood gadolinium contrast-enhanced T1-weighted sequence with fat suppression and time-of-flight MRA of the circle of Willis. Imaging features were assessed by 2 experienced neuro-radiologists and indexed to time of imaging relative to the date of symptom onset. The images were then placed in sequential order, and features summarised as a function of time as an aggregate of patients.

Findings

The median age was 52 years with 2/13 (15%) being males. Median time to scan from symptom onset was 0.5 months. Mild vessel wall enhancement and thickening was noted in 4 patients (30%), while 6 patients had wall thickening alone. Remaining 3 patients only showed multifocal stenosis. Three patients (23%) were on steroids at time of initial scan. Nine patients (63%) had follow up imaging with a median follow up of 2.5 months. At follow up, 7/9 patients showed resolution of the enhancement and wall thickening while 1 patient had mild vessel wall enhancement and another had vessel wall thickening.

Conclusion

In this limited retrospective review of RCVS patients, there is a clear improvement over time in terms of vessel wall enhancement and thickening. Vessel wall thickening and enhancement was more vivid at earlier time points and reduced over time. HRMR imaging of the vessel walls may provide corroboration of clinical onset and track resolution of RCVS as well as differentiate the disease from other vasculopathies. Further research is needed.

Disclosures

R. Cerejo: None. F. Hui: None. S. Jones: None. E. Obusez: None. T. Hammad: None. R. Hajj-ali: None. K. Uchino: None.
P-018 Effect of pitavastatin on preventing ischaemic complications with carotid artery stenting: a multicentre prospective study
Authors: Takayama K , Myouchin K , Ikeda N , Sakamoto M , Nakagawa I , Wada T , Masuo O , Nakahara I , Tanemura H , Toma N , Maeda M , Suzuki H , Taki W
Published: July 2013

Background

Carotid artery stenting (CAS) is becoming an alternative to carotid endarterectomy (CEA). However, periprocedural ischaemic stroke is one problem associated with CAS. Statin therapy can reportedly reduce periprocedural complication rates in coronary intervention. This study was designed to assess whether preoperative statin therapy reduces the risk of periprocedural ischaemic complications with CAS.

Material and Methods

In this prospective study at 11 centres, patients with carotid stenosis (symptomatic ≥50%, asymptomatic ≥80%) and at high risk of requiring CEA, but without previous statin treatment were divided into two groups by low-density lipoprotein cholesterol level (LDL-C). With LDL-C≥120 mg/dl, the previous stain (PS) group received pitavastatin at 4 mg/day for 4 weeks. With LDL-C <120 mg/dl, the non-PS group received no statin therapy for 4 weeks. After 4 weeks, both groups underwent CAS. Frequencies of new ipsilateral ischaemic lesions on diffusion-weighted imaging (DWI) within 72 h after CAS and major adverse events (MAEs) (defined as transient ischaemic attack, stroke, myocardial infarction or death) within 30 days were assessed.

Results

Among the 80 patients enrolled, 61 patients (PS group, n=31; non-PS group, n=30) fulfilled the inclusion criteria. New ipsilateral ischaemic lesions were identified in 8 of 31 patients (25.8%) in the PS group and 16 of 30 patients (55.3%) in the non-PS group (P=0.027). MAE occurred in 0 patients in the PS group and in 3 of 30 patients (10.0%) in the non-PS group (P=0.07).

Conclusion

Pretreatment with pitavastatin significantly reduced the frequency of periprocedural ischaemic complications associated with CAS.

Disclosures

K. Takayama: None. K. Myouchin: None. N. Ikeda: None. M. Sakamoto: None. I. Nakagawa: None. T. Wada: None. O. Masuo: None. I. Nakahara: None. H. Tanemura: None. N. Toma: None. M. Maeda: None. H. Suzuki: None. W. Taki: None.