bluuebunny/crossref_metadata_2025_split huggingface dataset:
E-010 Tips and Tricks in using Onyx in Preoperative Embolization of Hypervascular Intracranial Tumors
Authors: Reddy S , Thomas A , Fusco M , DiNobile D , Ogilvy C 
Published: July 2014

Onyx embolization is a well-established preoperative treatment of cerebrovascular arterio venous malformations and fistulae. We report four cases of hypervascular extraaxial tumor embolization using Onyx administration as an adjunct to traditional particle embolization and coils.We report three cases of meningioma and one case of hemangiopericytoma. These tumors are highly vascular tumor arising from the meninges, the core of the tumor predominantly supplied by the middle meningeal artery and the periphery supplied by parasatization by intracerebral branches.Hypervascular extraaxial tumor resection may cause very high volume blood loss during open surgery. Presurgical embolization of these lesions has been proven to significantly decrease intraopertaive blood loss and facilitate subsequent surgical resection. Various agents has been used in the past for embolization of these tumors including polyvinyl alcohol (PVA), gelfoam powder, gelatin microspheres, liquid adhesives and coils. For the last few decades until recently, PVA particle embolization has been the mainstay of embolization and has been widely used. Onyx is a nonpolymerizing liquid agent composed of ethylene-vinyl alcohol copolymer dissolved in dimethyl sufloxide. When injected, Onyx precipitates within vessels forming a spongy cast.We report the use of Onyx in the embolization of four cases of hypervascular extraaxial tumors. The average was 57 yrs of age and 2 males and 2 females. Technique included a guide catheter placement in the external carotid artery and a microcatheter in the distal branch of the middle meningeal artery. The guide catheter we used was a 6F Neuron catheter and the microcatheters used included marathon microcatheter and more recently a DUO catheter. A 0.38 DAC was also used in one of the cases.Advantages of Onyx embolization include a more controlled injection due to gradual precipitation in a centripetal fashion which allows for slower and more accurate injections as well as penetration of very small calibre vessels. It also has the advantages of penetrating into the branches supplied by other vascular territories. Special caution is recommended to make sure the onyx doesn’t reflux into the intracerebral arteries supplying the periphery of the tumor.In the first case we did not use the particles. During embolization using Onyx, there was occlusion of the catheter with onyx at the catheter tip and Onyx wouldn’t go forward and was only refluxing back and we had to abort the procedure. Although the major vessel supplying the tumor was thrombosed the tumor core itself was not embolised. In all the later cases we embolised initially with particles and then went on to complete the embolization with Onyx. This report furthers the growing body of literature confirming the safety and efficacy of Onyx in the preoperative embolization of Intracranial highly vascular extra axial tumors.DisclosuresS. Reddy: None. A. Thomas: None. M. Fusco: None. D. DiNobile: None. C. Ogilvy: None.
E-012 National Trends for the Utilization of Cerebral Angiography in Patients with Unruptured Aneurysms: 1999–2009
Authors: Choudhri O , Feroze A , Mantha A , Steinberg G , Do H 
Published: July 2014

IntroductionThe utilization of cerebral angiography in the diagnosis and management of patients with unruptured cerebral aneurysms varies across the United States. Given advances in noninvasive imaging, such as CT and MR angiography, patients with unruptured aneurysms may never undergo cerebral angiography. This study explores shifting trends in the utilization of angiography for management of such lesions across the U. S. from 1999–2009.MethodsThe National Inpatient Sample was used to identify patients carrying a primary ICD-9 diagnosis code of unruptured aneurym (430.0) between 1999–2009. The primary outcomes were compared across subgroups undergoing cerebral angiography in the management of their pathology versus those who did not. The data were analyzed using univariate and multivariate regression (SAS).ResultsThere were 127579 total admissions with a primary ICD-9 diagnosis of unruptured aneurysms between 1999–2009 per NIS weighted estimates. The total number of patients who underwent cerebral angiography and subsequent clipping were 19412 between 1999–2009. During the same time period 28095 patients underwent coiling after cerebral angiography. For the year 1999, 77% patients were clipped and 23% coiled after cerebral angiography (p < 0.0001). Conversely for the year 2009, 29% patients were clipped and 71% coiled after cerebral angiography (p < 0.0001). These trends were less pronounced though significant in the patients who did not undergo initial cerebral angiography, such that for the year 1999, 88% patients with unruptured aneurysms were clipped while only 12% were coiled.ConclusionsPatients with unruptured cerebral aneuryms who undergo cerebral angiography are more likely to undergo endovascular coiling rather than clipping.DisclosuresO. Choudhri: None. A. Feroze: None. A. Mantha: None. G. Steinberg: None. H. Do: None.
O-008 The Financial Impact of ADAPT for Endovascular Treatment of Acute Ischemic Stroke
Authors: Turk A , Turner R , Chaudry M , Spiotta A 
Published: July 2014

IntroductionThe use of mechanical thrombectomy for treatment of acute ischemic stroke has significantly advanced over the last 5 years. Little data is available analysing the cost relative to the clinical and angiographic outcomes. The aim of this study is to analyze the cost and efficacy of current stroke therapy.MethodsA retrospective review of the chart and hospital financial database of all ischemic stroke cases from 2009–2013 was performed. Three discreet treatment methodologies evolved during this time: traditional Penumbra System (PS), stent retriever with local aspiration (SRLA) and A Direct Aspiration first Pass Technique (ADAPT). Statistical analysis of clinical and angiographic outcomes and costs for each group was performed.Results222 patients (45% male) underwent mechanical thrombectomy, with 88% of strokes present in the anterior circulation. PS was used 58%, SRLA 13% and ADAPT in the remaining 29% of cases. PS was able to achieve TICI2b/3 revascularization 79%, SRLA was effective 83% and ADAPT 95% of the time. The average total cost of hospitalization for patients treated with PS was $51,599, SRLA was $54,700 and ADAPT $33,611 (p < 0.0001). The average length of stay was significantly less for ADAPT (7 days) than PS (10.6 days), but not for SLRA (8.3 days) (p = 0.02). Average time to recanalization for PS was 88 min, SRLA was 47 min and ADAPT was 37 min (p < 0.0001). Similar rates of good neurologic outcomes were seen in group PS (36%) as group SRLA (43%) and ADAPT (47%) (p = 0.4).ConclusionThe most cost effective approach to a large intracranial vessel occlusion appears to be direct aspiration with a large bore catheter (without the separator) first and if this fails then proceed with other devices such as a stentriever.DisclosuresA. Turk:1; C; Stryker, Microvention, Penumbra. 2; C; Stryker, Microvention, Covidien, Penumbra, Siemens. 3; C; Stryker, Microvention, Covidien, Siemens, Penumbra. R. Turner: 1; C; Penumbra, Microvention, Stryker. 2; C; Penumbra, Microvention, Stryker. 3; C; Penumbra, Microvention, Stryker. M. Chaudry: 1; C; Penumbra, Microvention, Stryker. 2; C; Penumbra, Microvention, Stryker. 3; C; Penumbra, Microvention, Stryker. A. Spiotta: 1; C; Penumbra, Microvention, Stryker. 2; C; Penumbra, Microvention, Stryker. 3; C; Penumbra, Microvention, Stryker.
E-020 Safety and Efficacy of the Pipeline Embolization Device in 100 Small Intracranial Aneurysms
Authors: Chalouhi N , Zanaty M , Whiting A , Yang S , Tjoumakaris S , Hasan D , Starke R , Hann MS , Hammer C , Kung D , Rosenwasser R , Jabbour P 
Published: July 2014

ObjectiveFlow diverters are increasingly used for treatment of intracranial aneurysms. In most series, the PED was used for the treatment of large, giant, complex, and fusiform aneurysms. Little is known about the use of the PED in small aneurysms. The purpose of this study was to assess the safety and efficacy of the PED in small aneurysms (≤ 7 mm).MethodsA total of 100 consecutive patients with small aneurysms (≤ 7 mm) were treated with the PED at our institution between May 2011 and September 2013. Data on procedural safety and efficacy was retrospectively collected.ResultsMean aneurysm size was 5.2 ± 1.5 mm. Seven patients had sustained a subarachnoid haemorrhage. All except 5 aneurysms (95%) arose from the anterior circulation. The number of PEDs used was 1.2 per aneurysm. Symptomatic procedure-related complications occurred in 3 (3%) patients: 1 distal parenchymal haemorrhage managed conservatively and 2 ischemic events. At the latest follow-up (mean, 6.1 months), 52 (71%) aneurysms were completely occluded (100%), 10 (14%) were near-completely occluded (≥90%), and 11 (15%) were incompletely occluded (<90%). Six aneurysms (8%) required further treatment. Increasing aneurysm size (OR= 3.9; 95% CI: 0.99–15; p = 0.05) predicted retreatment. All patients achieved a favorable outcome (mRS 0–2) at follow-up.ConclusionIn this study, treatment of small aneurysms with the PED was associated with low complication rates and high aneurysm occlusion rates. These findings suggest that the PED is a safe and effective alternative to conventional endovascular techniques for small aneurysms. Randomised trials with long-term follow up are necessary to determine the optimal treatment that leads to the highest rate of obliteration and best clinical outcomes.DisclosuresN. Chalouhi: None. M. Zanaty: None. A. Whiting: None. S. Yang: None. S. Tjoumakaris: None. D. Hasan: None. R. Starke: None. S. Hann: None. C. Hammer: None. D. Kung: None. R. Rosenwasser: None. P. Jabbour: None.
E-023 Consecutive Endovascular Treatment of Ruptured Very Small (<3 mm) Anterior Communicating (ACom) Artery Aneurysms: A Single Center Experience
Authors: Asif K , Teleb M , Sattar A , Lazzaro M , Fitzsimmons B , Lynch J , Zaidat O 
Published: July 2014

BackgroundThe anterior communicating (ACom) artery is the most common location of cerebral aneurysms harbouring upto 30–37% of all treated aneurysms. Amongst all ruptured aneurysms, the proportion of patients with very small aneurysms ranges from 12–18%. Treatment of very small aneurysms (<3 mm) of the anterior communicating artery presents a unique set of challenges for both surgical as well as endovascular techniques.ObjectiveTo report the immediate and long-term clinical as well as radiographic outcomes of consecutive patients with ruptured very small anterior communicating artery (ACOM) aneurysms treated with endovascular technique.MethodsA prospectively maintained single institution neuro-endovascular database was accessed to identify consecutive cases of very small (<3 mm) ruptured ACom aneurysms treated endovascularly between 2006 and 2013. Clinical, demographic, radiographic, and procedural data were retrospectively obtained through chart review.ResultsA cohort of 20 consecutive patients with ruptured very small (<3 mm) ACom artery aneurysms were treated endovascularly including 13 females and 7 males with a mean age of 58.4 ± 12.9 yrs. Average maximum aneurysm diameter was 2.66 (± 0.41) mm. Hunt-Hess grade 1–3 for 14 (70%) patients and 4 for 6 (30%) patients. Dome to neck ratio was less than 2 for 13 (65%) of the aneurysms. Four (20%) aneurysms were bilobed. Aneurysm projection was antero-superior in 11 (55%), antero-inferior in 6 (30%) and postero-superior in 3 (15%). Primary coiling was performed for 16 (80%) aneurysms and balloon assistance was used for 4 (20%). Complete aneurysm occlusion was achieved for 17 (85%) aneurysms and near complete for 3 (15%) aneurysms. There were no symptomatic peri-procedural complications. Intra-operative perforation (IOP) occurred in 2 (10%) patients without any clinical worsening or need for an external ventricular drain. Thromboembolic event (TEE) occurred in 1 (5%) patient without clinical worsening or new radiologic infarct. Median clinical follow up was 12 (± 14.1) months and median imaging follow up was 12 (± 18.4) months. There were no instances of re-bleeding during follow up. At the 3 month clinic follow up, modified Rankin scale was 6 for one patient related to anaplastic astrocytoma. Of all the surviving 19 patients, post treatment clinical status either improved or remained stable. Recanalization with a neck residual occurred in two (10%) aneurysms and both were retreated with additional primary coiling and stent assistance.ConclusionEndovascular treatment of very small ACom aneurysms can be performed with acceptable rates of complications and recanalization. Robust conclusions can be drawn only after further evaluation with larger number of patients and longer follow-up.DisclosuresK. Asif: None. M. Teleb: None. A. Sattar: None. M. Lazzaro: None. B. Fitzsimmons: None. J. Lynch: None. O. Zaidat: None.
E-024 A Single-center Experience of Carotid Artery Stenting in Patients with Carotid Stenosis
Authors: Lee J 
Published: July 2014

BackgroundCarotid artery stenting (CAS) has emerged as a potential alternative to endarterectomy and its clinical practise dramatically increased in many parts of the world. This study aims to determine the safety and post-procedural complication of carotid artery stenting at a single-center institution in Korea.Patients and methodsWe retrospectively analyzed all CAS procedures performed at our institution between March 2009 and February 2013.ResultsDuring the observation period, a total of 87 CAS procedures were attempted in 79 patients with stenoses of the internal carotid artery of which 66 (75.9%) were symptomatic and 21 (24.1%) were asymptomatic. The patient group comprised 69 men (87.3%) and 10 women (12.7%) with a mean age of 67.9 years (range, 49–83 years). Stents were successfully inserted in 85 (97.7%) cases. Post-procedural vascular events to discharge occurred in 10 patients (3 cases of cerebral hyperperfusion syndrome, 7 cases of ischemic stroke). Among 10 patients, death and a permanent severe neurologic deficit occurred in 3 patients with cerebral hyperperfusion syndrome and 1 patient with ischemic stroke.ConclusionsPost-procedural death or a permanent severe neurologic deficit after CAS occurred due to mainly hyperperfusion syndrome in our study.DisclosuresJ. Lee: None.
E-025 Transorbital Carotid-Cavernous Fistula Embolization with Ruby Coils
Authors: Milburn J , Pansara A , Perry M , Vidal G , Eubanks B 
Published: July 2014

PurposeA carotid cavernous fistula (CCF) is an abnormal arteriovenous connexion between the internal carotid artery (ICA) or the external carotid artery (ECA) and the cavernous sinus. Symptoms range from benign ocular disturbances and cranial nerve palsies to severe or rapid vision loss and intracranial haemorrhage. Primary treatment options include transvenous or transarterial embolization. Coil embolization of the cavernous sinus is often a long procedure using many small diameter microcoils with high radiation doses. The purpose of this case is to illustrate the use of larger diameter (0.020 inch) Ruby coils (Penumbra Inc.) as a highly efficient alternative method of embolization.MethodsAn 84-year-old woman presented to her local emergency room for progressive diplopia and loss of visual acuity over several weeks. Computed tomography (CT) of the head and CT angiography (CTA) revealed enlarged superior ophthalmic veins suggesting a CCF. Cerebral angiography was performed demonstrating an indirect CCF supplied by small branches of both the right and left internal and external carotid arteries with primary venous drainage into the right superior ophthalmic vein. Transvenous treatment from the femoral approach at the same setting was unsuccessful due to complete occlusion of the inferior petrosal sinus (IPS) bilaterally.Definitive treatment was then performed via direct transorbital approach. An oculoplastic surgeon provided direct surgical exposure to the right superior ophthalmic vein. The neurointerventionalist then punctured the exposed vein with a micropuncture needle to advance a 4-French short sheath. A Penumbra PX SLIM microcatheter was then advanced to the posterior cavernous sinus at the midline. 7 Ruby coils were deployed into the cavernous sinus and right SOV to occlude the CCF. Occlusion of the CCF was achieved by deployment of 150 cm of Penumbra 0.020-inch calibre detachable coils. Procedure time was 21 min from introduction of the 1stcoil to microcatheter removal.ResultsComplete occlusion of the CCF was demonstrated on the final right and left common carotid angiograms. Her visual acuity improved on postoperative day 1. At her 1 week clinic visit, visual acuity was nearly at baseline, proptosis was improved, and diplopia improved. Her 6thnerve palsy was 50% improved on the 3 month follow-up.ConclusionEmbolization of an indirect CCF may be performed efficiently using large diameter Ruby coils. This case presentation illustrates a direct transorbital approach via the SOV with operative photographs and pertinent angiographic images. The coil time was short due to the efficiency of the large (0.020 inch) diameter and long available lengths of Ruby coils.DisclosuresJ. Milburn: 3; C; Penumbra, Inc.. A. Pansara: None. M. Perry: None. G. Vidal: 3; C; Penumbra, Inc., Covidien. B. Eubanks: None.
Privacy Auctions for Recommender Systems
Authors: Dandekar Pranav , Fawaz Nadia , Ioannidis Stratis 
Published: July 2014

We study a market for private data in which a data analyst publicly releases a statistic over a database of private information. Individuals that own the data incur a cost for their loss of privacy proportional to the differential privacy guarantee given by the analyst at the time of the release. The analyst incentivizes individuals by compensating them, giving rise to a
privacy
auction
. Motivated by recommender systems, the statistic we consider is a linear predictor function with publicly known weights. The statistic can be viewed as a prediction of the unknown data of a new individual, based on the data of individuals in the database. We formalize the trade-off between privacy and accuracy in this setting, and show that a simple class of estimates achieves an order-optimal trade-off. It thus suffices to focus on auction mechanisms that output such estimates. We use this observation to design a truthful, individually rational, proportional-purchase mechanism under a fixed budget constraint. We show that our mechanism is 5-approximate in terms of accuracy compared to the optimal mechanism, and that no truthful mechanism can achieve a 2 −
ε
approximation, for any
ε
> 0.
Cloudsweeper and data-centric security
Authors: Snyder Peter , Kanich Chris 
Published: July 2014

Most security online is binary, where being authorized to access a system allows complete access to the requested resource. This binary system amplifies the harm of giving access to an unauthorized individual and motivates system designers to strengthen access control mechanisms to the point where they become so strong as to be nearly insurmountable for illegitimate and legitimate users alike.
As a result, Internet users are required to jump through several hoops to access their data: ever longer passwords, multiple authentication factors, or time consuming CAPTCHAs. Users must always provide strong proof of their identity, regardless of whether they want to check their email for something as innocuous as a movie time or as serious as a medical test result. Not surprisingly, users often disable or refuse to use these tedious security options [2, 5, 7].

Users may be better served by a
data-centric
approach to security, where systems are sensitive to the differing security needs of data, even within a single account or collection. A data-centric approach can apply strong security only when the data being protected warrants it, while allowing users a less encumbered experience the majority of the time. Machine learning techniques can automate the detection of sensitive information, freeing users from the tedious task of sorting their data into low and high security categories. With less friction involved in securing their data, users may be more likely to use strong security where available, resulting in a more secure Internet for everyone.

We present
Cloudsweeper
, a tool that applies a data-centric approach to security to the specific case of plain text password sharing in Gmail accounts. Cloudsweeper detects and applies an additional layer of encryption to plain text passwords in a user's email account, while allowing the user to access the rest of their email archive as normal. Public use of Cloudsweeper shows that such a data-centric approach to securing data can be an effective way of providing users more security while still being acceptably convenient.
Low Folate Levels Are Associated with Reduced Risk of Colorectal Cancer in a Population with Low Folate Status
Authors: Gylling Björn , Van Guelpen Bethany , Schneede Jörn , Hultdin Johan , Ueland Per Magne , Hallmans Göran , Johansson Ingegerd , Palmqvist Richard 
Published: July 2014

Abstract
Background: A diet rich in folate is associated with a reduced colorectal cancer risk, whereas the role of circulating levels is less clear. The aim of this study was to relate prediagnostic plasma folate, vitamin B12, and homocysteine concentrations to the risk of colorectal cancer.
Methods: This was a prospective case–control study of 331 cases and 662 matched controls nested within the population-based Northern Sweden Health and Disease Study. Median follow-up time from recruitment to diagnosis was 10.8 years.
Results: Plasma folate concentrations were positively related to colorectal cancer risk; multivariate odds ratios were 1.62 [95% confidence intervals (CI), 1.08–2.42] and 1.42 (95% CI, 0.94–2.21) for the middle and highest versus lowest tertile, respectively. In subjects with follow-up &lt;10.8 years, a statistically significant doubled risk was observed for the middle and highest versus lowest tertile, whereas findings for longer follow-up times were null. A positive risk relationship was also observed for tumor stage III–IV but not I–II. Plasma vitamin B12 concentrations were inversely associated with rectal cancer risk. Homocysteine was not significantly related to colorectal cancer risk.
Conclusions: In this population-based, nested case–control study, low plasma folate concentrations were associated with a reduced colorectal cancer risk. This protective role was mainly observed in subjects with higher tumor stage or shorter follow-up time between recruitment and diagnosis. Low circulating folate status may protect against colorectal cancer or suppress progression of preneoplastic or neoplastic lesions.
Impact: These findings may have relevance for the ongoing debate about mandatory folic acid fortification of flour. Cancer Epidemiol Biomarkers Prev; 23(10); 2136–44. ©2014 AACR.