bluuebunny/crossref_metadata_2025_split huggingface dataset:
P-035 Effect of pre-operative embolization on AVM blood flow
Authors: Alaraj A , Aletich V , Ivanov A , Carlson A , Oh G , Charbel F , Amin-Hanjani S 
Published: July 2012

IntroductionBoth surgical resection and endovascular embolization are important tools in the treatment of arteriovenous malformations (AVMs). Prior to surgical resection of AVMs, pre-operative embolization is often selectively employed for large or high-flow AVMs, to reduce risk of intra-operative hemorrhage and mitigate the potential for bleeding related to “normal perfusion breakthrough” in the peri-operative period. A primary goal of the embolization is to sequentially and gradually reduce flow in the AVM; the success in achieving this goal is primarily determined through subjective and qualitative assessment of the angiographic runs pre and post embolization. We sought to directly measure the effects of embolization on AVM flow using Quantitative Magnetic Resonance Angiography (QMRA).MethodsMedical charts, cerebral angiograms, and flow measurements were reviewed in patients with QMRA measurements of AVM flow pre and post embolization. Total AVM flow was calculated based on the aggregate flow within the primary arterial feeders, or flow measured from single draining veins. AVM flows were compared pre and post embolization. All sessions of embolization were performed with N-BCA glue except three sessions where Onyx was used.Results51 AVM patients were evaluated with QMRA. Among those, 17 patients had flow measurements pre and post embolization. A total of 42 sessions of embolization were performed (range 1–6 per patient). Average AVM flow prior to treatment was 439 cc/min, ranging from 129 to 952 cc/min in AVMs from 2.3–32 cc in size (median 6.4 cc). The median number of pedicles embolized per session was 3 (range 1–5). Flow dropped by a mean of 133 cc/min (range 14–410 cc/min) per each session of embolization, representing an average 40% flow decline per session relative to flows immediately prior to the embolization. In larger AVMs, overall flow changes were sometimes not evident until the second or third sessions of embolization, suggesting re-channeling of flow through remaining compartments of the nidus. As compared to the baseline, there was an overall 67% (range 27%–99%) reduction in AVM flow at the end of multiple sessions of embolization, with mean AVM flow dropping to 103 cc/min (range 5–300 cc/min) before the surgery. Interestingly, the number of pedicles embolized per session did not correlate with the flow drop, which also correlated poorly with subjective determinations of the extent of embolization at time of angiography.ConclusionFlow alterations induced by embolization can be quantified, and may provide a more robust strategy to determine the number and efficacy of preoperative embolization sessions.Competing interestsA Alaraj: ev3, Cordis-Codman. V Aletich: Micrus. ev3, Cordis-Codman. A Ivanov: None. A Carlson: None. G Oh: None. F Charbel: VasSol Inc. S Amin-Hanjani: None.
P-042 Combined intra-arterial thrombolysis and mechanical thrombectomy versus mechanical thrombectomy endovascular outcomes in acute ischemic stroke: Abstract P-042 Table 1
Authors: Sehgal S , Sharma J , Kulhari A , Shams T , Vargas E , Moradzadeh N , Jung R , Blackham K 
Published: July 2012

BackgroundEndovascular intervention is an important treatment option for patients with acute ischemic stroke who are ineligible for intravenous thrombolysis or fail to respond to such therapy. Endovascular treatments include intra-arterial thrombolysis (IAT) and mechanical thrombectomy (MT). Limited data exists regarding the safety and efficacy of a combination approach using IAT and MT.ObjectivesTo assess the safety and efficacy of combined mechanical and IAT therapy compared to MT alone.MethodsRetrospective chart review was performed in 200 consecutive patients who underwent endovascular treatments for acute ischemic stroke at our center between 2007 and 2011. 115 patients met inclusion criteria of MT alone versus combined MT and IAT. We compared outcome parameters between these two groups including discharge NIHSS, modified Rankin Score (mRS), rate of partial to complete recanalization (TIMI 2–3), symptomatic intracerebral hemorrhage, and all cause mortality.ResultsA total of 115 patients underwent MT alone or received combined therapy. In the MT only group, mean age was 69±13.32 and median initial NIHSS was 17. Of the combined therapy group, 66±16 was the mean age and median initial NIHSS was 18.ConclusionsIn our experience combination MT and IAT in the treatment of acute ischemic stroke had a trend toward higher recanalization rates and number of patients with clinical improvement, as well as, lower discharge NIHSS and higher percentage of independently ambulating patients discharged as compared to MT alone. Despite higher hemorrhage and slightly increased mortality rates, the combined therapy group trended toward better clinical outcomes.Competing interestsNone.Abstract P-042 Table 1Primary outcomes between MT only and combined therapy groupsOutcomeMechanical thrombectomy only (N=40)Combined MT and IAT (N=75)Discharge NIHSS129Clinical improvement (NIHSS >4)19 (47.5%)37 (55.2%)TIMI 2–325 (62.5%)57 (76.0%)Discharge mRS ≤33 (7.5%)10 (13.3%)Symptomatic ICH3 (7.5%)13 (17.0%)Mortality8 (20%)20 (26.7%)
E-017 Impact of integrated cerebrovascular program on outcomes in patients with intracranial aneurysms
Authors: Krishna V , Turner R , Chaudry I , Turk A 
Published: July 2012

IntroductionRecent evidence indicates that multidisciplinary care improves patient outcomes for cerebrovascular (CV) disease. A multidisciplinary, integrated CV program was recently instituted at a high volume tertiary referral center, providing the opportunity to evaluate patient outcomes before and after its introduction.MethodologyA retrospective chart review was performed on all new patient encounters for a 6-month time period each before and immediately after the introduction of the CV program, as well as at a more recent 6 month time period to evaluate long-term results. Data were collected on demographic variables, rupture status, medical comorbidities, hospital complications, in-hospital procedures, hospital course, and modified Rankin score at discharge and follow-up.ResultsThe total number of patients treated increased from 55 in the 6-month time period before the introduction of CV program to 112 in the most recent time period (p<0.05). Both the number of surgical clipping and endovascular coiling procedures increased (p<0.05). An increase in severity of illness was observed, with a significant increase in patients with multiple comorbidities (30.5% vs 34.7%, p=0.035). Mean length of hospital stay decreased from 12.22±13.26 days before the program to 9.23±12.04 days in the most current data, mainly due to a statistically significant decrease in intensive care unit length of stay between those time periods (p<0.05). Additionally, fewer systemic complications were observed in the most recent time period as compared to before the introduction of CV program.ConclusionsCreation of an integrated CV program at a large volume tertiary referral center resulted in better outcomes for an increased number of more medically complicated patients with intracranial aneurysms. This study provides preliminary data supporting the development of an integrated model of multidisciplinary care for the management of CV disease.Competing interestsNone.
E-026 An analysis of the anterior circulation cerebrovascular geometry. Baseline measurements of vessel diameter, length and taper
Authors: Rai A , Cline B , Hogg J 
Published: July 2012

BackgroundEndovascular interventions typically require placement of a device in the cerebral vasculature. Knowledge of the cerebrovascular geometry can aid in designing conformable devices. The study's objective was to establish baseline measurements of the anterior circulation in the cerebral vasculature including diameter, length and vessel taper.Materials and MethodsThe sample size was determined for four cohorts based on gender and side; males-right, males-left, females-right and females-left. We reviewed similar measurements in the literature and conservatively chose a SD of 0.5 mm. Using a margin of error of 0.2 and a 95% CI yields a sample size of 25 patients for each sub-group for a total of 100 patients. The sample was calculated from a patient population that had undergone an intracranial CT angiogram. The age cut-off was set at 40 years based on our experience that most patients undergoing neurovascular interventions are above this age group. Patients with any vascular abnormality on the CTA were excluded. Thus 50 consecutive male and female patients were included. The vessel diameter was measured at the proximal cavernous ICA, the ICA terminus, the MCA origin and an M2 origin. The vessel length between these endpoints was calculated along the centerline. The vessel taper was calculated as the change in caliber per mm of length.ResultsThe mean length of the ICA from the proximal cavernous segment to the ICA terminus was 33.1±6.1 mm. The mean diameter at the proximal cavernous ICA and the ICA terminus was 5±0.6 mm and 3.6±0.4 mm respectively. The mean ICA taper was 0.04±0.02/mm. For the MCA, the diameter at the M1 and M2 origins measured 3.1±0.4 mm and 2.4±0.4 mm respectively. The mean MCA length was 22.5±8.1 mm. There was no significant difference between male and female patients and between right and left sides. Patients who were older than 60-years had longer ICAs (p=0.02), larger ICA-cavernous (0.003), ICA-terminus (<0.0001) and MCA origin (p=0.01) diameter than those younger than 60-years.ConclusionWe demonstrate the baseline dimensions of the anterior cerebrovascular circulation. Calculation of the vessel taper has not been done before and is important as an increasing number of endo-luminal devices are becoming available. Knowledge of the vessel taper can allow for development of more conformable devices thus enhancing their effectiveness. We are currently analyzing similar data for the posterior circulation and if accepted intend to present that along with the anterior circulation.Competing interestsA Rai: Stryker Neurovascular. B Cline: None. J Hogg: None.
E-033 Bow Hunter's syndrome: an unusual cause of symptomatic vertebral artery stenosis
Authors: Miller D , Tawk R , Barrett K 
Published: July 2012

Introduction/purposeBow Hunter's syndrome is an unusual symptomatic vertebral artery syndrome resulting from intermittent mechanical compression of the vertebral artery. We describe a case of symptomatic left vertebral artery compression diagnosed by dynamic cerebral angiography and discuss the pathophysiology, diagnosis, and treatment of this unusual syndrome.Materials/methodsA 44-year-old right-handed male was transferred to Mayo Clinic hospital after being admitted to an outside hospital with left-sided weakness and numbness and difficulty with balance. The patient became symptomatic while driving his truck on the highway about 10 days before. An outside MRI confirmed an acute CVA involving the cerebellum and left medulla. An MR angiogram suggested stenosis of the left vertebral artery in the mid cervical region. Cerebral angiography revealed only mild stenosis of the left vertebral artery in the neutral position. Angiograms with the patient had turned to the left revealed almost complete occlusion of the left vertebral artery. Turning the head to the right essentially completely resolved the stenosis. CT angiography with three-dimensional reconstruction confirmed a large uncovertebral spur encroaching on the foramen transversarium at C5-6.ResultsThe patient was evaluated for endovascular therapy verses open surgical treatment. He was treated with anterior cervical discectomy and fusion with surgical excision of the spur. This resulted in complete resolution of his symptoms.ConclusionsBow Hunter's syndrome is an unusual mechanical entrapment syndrome of the vertebral artery which can be difficult to diagnose with conventional non-invasive imaging. Dynamic cerebral angiography can lead to an appropriate diagnosis. Treatment can be surgical or endovascular, and can lead to complete resolution of symptoms.Competing interestsNone.
E-005 Accuracy of software for intracranial aneurysm geometry quantification: Abstract E-005 Figure 1
Authors: Murayama Y , Mohamed A , Takao H , Ishibashi T , Yuki I 
Published: July 2012

Introduction/purposeEndovascular treatment planning for intracranial aneurysms requires accurate quantification of aneurysm geometry. Today, aneurysm geometry is typically measured manually on an angiographic workstation based on three-dimensional (3D) Digital Subtraction Angiography (DSA) images. Since accuracy and reproducibility of manual measurements are user dependent, computer-aided approaches have been recently proposed. We evaluated prototype software for intracranial aneurysm geometry quantification and compared generated measurements to manual measurements from two experienced raters.Materials and MethodsWe examined 25 saccular unruputured single intracranial aneurysms (sidewall = 17, bifurcation = 8) treated via endovascular coiling at our institution between August 3, 2011 and February 23, 2012. Based on 3D DSA images, Manual measurements of the neck length (N), dome height (H), dome diameter (D) were obtained by two independent experienced raters. The aneurysm volume (V) was computed manually via an image punching and voxel counting approach. Subsequently, prototype cranial aneurysm analysis software (Siemens AG, Forchheim, Germany) was applied to the 3D DSA images to measure the same quantities. The software requires the user to manually mark the aneurysm dome via one point click and the parent artery via two point clicks, proximal and distal to the aneurysm.ResultsThe software to average rater errors were compared to inter-rater variability. No statistically significant differences were found between the two error distributions for N, H, D (p=0.371, p=0.567 and p=0.195, respectively). The average software-to-rater errors were N=0.55±1.03 mm, H=0.49±0.58 mm and D=0.45±0.39 mm. The largest errors in N (4.23 mm) and H (2.42 mm) occurred in cases where the 3D image could not adequately separate the aneurysm dome from the parent vessel. For V, data from only one rater were available. The average relative error was 7.76%±6.68% with maximum of 20.9%.ConclusionsResults indicate good agreement between measurements obtained by the software and two independent manual sets of measurements. In cases where 3D imaging did not adequately separate the aneurysm dome from the neighboring blood vessels, the aneurysm neck length, dome height, and volume measurement errors were the largest. Manual corrections may be necessary in such cases. Further studies on a larger dataset of various aneurysm geometries are needed.Competing interestsY Murayama: Siemens AG. A Mohamed: Siemens AG. H Takao: None. T Ishibashi: None. I Yuki: None.Abstract E-005 Figure 1
E-061 Correlation between CT perfusion (CTP) and MRI in the setting of acute stroke
Authors: Ghobrial G , Chalouhi N , Zohra M , Dalyai R , Tjoumakaris S , Jabbour P , Dumont A , Rosenwasser R , Gonzalez L 
Published: July 2012

IntroductionDiffusion weighted imaging (DWI) has its limitations, as evidenced in the literature by reports of variable sensitivity and accuracy. Increasingly, reports of the utility of CT perfusion (CTP) are being made in predicting acceptable thrombolysis candidates. This is being done by evaluating infarct core and discriminating ischemic territory from penumbra in the acute setting.MethodsA single institution, retrospective review of 21 patients who underwent multimodal endovascular intervention for stroke from January 2010 to 2011 was conducted after institutional review board approval. Immediate CTP of the head and neck was obtained in all cases upon admission. Posterior circulation stroke, lacunar infarcts, and those unable to undergo MRI post-operatively were excluded. Calculated volumes of the penumbra from CTP data were compared to post-operative MRI volumetric calculations of the completed infarct. This data was contrasted to 21 control patients that were excluded from intervention, but had CTP and MRI in the acute setting.ResultsEleven patients in the interventional group and 10 patients in the control group received intravenous tissue plasminogen activator. In both the control group and interventional groups, DWI studies obtained after multimodal recanalization in all patients demonstrated diffusion restriction in the infarct core. Varying volumes of diffusion restriction were seen in the penumbra. The mean difference calculated between the mismatch area on CTP and the correlating diffusion restriction on MRI was a decrease of 43.01 cm3(p<0.05). In the interventional group, the area of restriction was less than the predicted mismatch area calculated. In the control group, 7 of the 21 patients (33%) had a net increase in the stroke territory. The calculated mean difference between the mismatch on CTP and the diffusion restriction on MRI was a decrease of 14.12 cm3(p<0.05).ConclusionsDWI and CTP are useful tools in the assessment of ischemic stroke patients in the acute interventional setting. By comparing mismatch on CTP to MRI diffusion restriction after endovascular intervention, we show a decreased conversion of penumbra to stroke than in the patients undergoing medical management alone. Larger, prospective studies with quantitative metrics are necessary for further evaluation of stroke patients.Competing interestsNone.
E-062 Stent-assisted embolization of 71 anterior cerebral artery aneurysms
Authors: Johnson A , Munich S , Heiferman D , Lopes D 
Published: July 2012

IntroductionAnterior cerebral artery aneurysms (ACAAs) comprised over half of the ruptured aneurysms in the International Subarachnoid Trial. These lesions tend to rupture at a smaller size than those at other locations. Endovascular treatment of ACAAs has provided excellent results, but until the introduction of intracranial stents, many ACAAs could not be treated without craniotomy. The current study analyzes the results of ACAA treatment using stent-assisted embolization.Materials and MethodsAfter being offered the options of observation, endovascular repair, and microsurgical treatment, 69 patients with 71 ACAAs underwent stent-assisted aneurysm repair. Three aneurysms were distal ACAAs. Eight were 10 mm or more in greatest diameter, and all aneurysms were <15 mm. Follow-up angiography was performed 6 months after treatment; then patients were followed with annual magnetic resonance angiography. Immediate, mid-term, and long-term radiographic results and complications were analyzed.ResultsAfter stent-assisted embolization, 33 (46.5%) ACAAs were completely occluded, 18 had residual neck, and 20 had residual filling. At first radiographic follow-up, 39 of 58 (67.2%) showed complete occlusion. Four aneurysms required retreatment, one with another stenting procedure. After stable initial follow-up angiography, no aneurysms worsened clinically or radiographically during the follow-up period. One patient treated with a three-stent construct died of periprocedural hemorrhage. One major stroke occurred during a hip surgery while the patient discontinued anti-platelet medications. These cases were the only aneurysm-related major morbidity (1.4%) and mortality (1.4%) during the follow-up period.ConclusionStent-assisted aneurysm treatment was a safe and effective option in this series of ACAAs with complex anatomy. Contrary to prevailing opinions regarding the durability of microsurgical and endovascular repair, aneurysms in the anterior cerebral artery distribution may be more likely to recur after clipping, and stent-assisted embolization may be durable after stable initial follow-up.Competing interestsA Johnson: None. S Munich: None. D Heiferman: None. D Lopes: Stryker, ev3, Penumbra.
E-072 Wake up symptomatic stroke in acute brain ischemia (WASSABI) clinical trial
Authors: Kass-Hout T , Kass-Hout O , Mokin M , Al Masry M , Nourollahzadeh E , Siddiqui A , Levy E , Synder K 
Published: July 2012

BackgroundStroke is the fourth leading cause of mortality and a major cause of long-term disability in the USA. IV tPA remains the only FDA-approved treatment for AIS. However, it is only approved when the time of onset is known to be <3 h. Approximately 25% of ischemic stroke patients awaken with stroke symptoms. This is called a Wake Up Stroke (WUS). The purpose of this study is to determine if WUS patients with a proof of salvageable penumbra on CT perfusion (CTP) will benefit from IV thrombolysis therapy or endovascular intervention.MethodsThis study is a single center, randomized, single-blinded and prospective study to compare between medical therapy and interventions in patients with WUS. Ninety patients with wake up ischemic stroke and considerable salvageable tissue on perfusion studies (defined as TTP >8 s and volume loss <20% of the size of the penumbra) will be randomized into one of three prospective groups: (1) Best medical therapy (standard of care with anti-platelets and statins), (2) Intravenous thrombolysis (total dose of 0.9 mg/kg) and (3) Intra-arterial intervention (IA t-PA and/or MERCI device and/or PENUMBRA device). The Choice of appropriate endovascular therapy will be decided by an experienced endovascular surgeon.Statistical analysisThis is an ongoing study. Efficacy end points will be assessed in the intention-to-treat analysis. The primary end point; modified Rankin Scale at 90 days (mRs-90 days) ≤2, will be compared among the different subgroups denoted previously by χ2distribution analysis using the SAS program (SAS V.9.1 Institute INC.). A comparison of NIHSS means among the three groups would also be performed at 24 h post ER presentation and at discharge. Initially One-Way Analysis of Variance (ANOVA) will be carried out. If the ANOVA analysis provides us with statistically significant results suggesting significant difference among the three arms, then Binary comparisons among the groups using Tukey multiple means comparison procedure will be performed. Using the means will be justified in our study since we aim to have a sample size of 90 subjects. Symptomatic intracranial hemorrhage will also be compared among the three groups.Competing interestsT Kass-Hout: Genentech. O Kass-Hout: None. M Mokin: None. M Al Masry: None. E Nourollahzadeh: None. A Siddiqui: NINDS 1R01NS064592-01A1, University at Buffalo. Shurtleff, Inc, Concentric Medical, ev3/Covidien Vascular Therapies, GuidePoint Global Consulting, Penumbra. Codman & Shurtleff, Inc, Genentech. Hotspur, Intratech Medical, StimSox, Valor Medical. Abbott Vascular, American Association of Neurological Surgeons, Neocure Group LLC, an Emergency Medicine Conference. E Levy: Codman & Shurtleff, Inc, ev3/Covidien Vascular Therapies, Boston Scientific. TheraSyn Sensors. Medical Ltd., Mynx/Access Closure. Boston Scientific. K Synder: Toshiba and ev3.