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Intra-aortic CT Angiography (IA-CTA) is a relatively new technique that shows promise in efficient diagnosis and evaluation of the angioarchitecture of spinal dural arteriovenous fistulae(sdAVF). The authors document the first reported use of a 4D-CT and C-arm fluoroscope in a hybrid interventional suite to evaluate a sdAVF. Time resolved IA-CTA is clinically feasible in the evaluation of sdAVF, has higher temporal resolution as compared to standard IA-CTA and reduced contrast load, radiation dose and potential for procedural complications as compared to standard spinal angiography.

Intracranial hemorrhagic metastases are a relatively common finding in patients with thyroid carcinoma. Consequently, more unusual vascular lesions may be overlooked in contemplating a differential diagnosis in this patient group. A 50-year-old female with previously treated papillary thyroid carcinoma presented to the emergency department following new onset seizures. Her work up revealed multiple intraparenchymal brain lesions, hyperdense on computed tomography and demonstrating susceptibility effect, T1 shortening and contrast enhancement on magnetic resonance imaging, suggestive of metastases. Subsequent studies revealed lesional architecture consistent with multiple cavernous malformations, made evident by resolution of edema and evolution of blood products. Clinicians should be aware of the possibility of unusual intracranial hemorrhagic lesions in oncology patients which may only become evident on serial imaging evaluation. Cavernous hemangioma has typical MRI characteristic features which includes “mulberry” appearance on T2-weighted and fluid attenuation inversion recovery images with varying internal signal intensity which indicates multiple stages of blood products within the cavernous hemangioma. The lesions commonly have a typical T2-weighted dark hemosiderin rim. Blood sensitive demonstrates prominent surrounding hypointensity representing blooming secondary to internal blood products and/or calcification, if present. Cavernous hemangioma may rarely demonstrate some degree of contrast enhancement. Perfusion imaging may show alteration in capillary permeability involving cavernous malformations which has been previously described in the literature.

Objectives. Foreign bodies of the external and middle ear are not uncommon; however, foreign bodies in the eustachian tube are rare. Here we describe the presentation, imaging, and endoscopic-assisted surgical management of a case of eustachian tube foreign body. Methods. A 34-year-old male was seen for evaluation of foreign body of the left eustachian tube while working with metal at a machine shop. Imaging and surgical management are highlighted and review of available literature regarding foreign bodies of the eustachian tube is presented. Results. A CT scan revealed a foreign body present approximately 1 cm into the bony eustachian tube. The patient underwent middle ear exploration which required endoscopic assistance to adequately visualize the foreign body. The foreign body was unable to be removed and required the creation of a bony tunnel lateral to the eustachian tube for visualization and access to the foreign body. Conclusions. This report presents a rare case of eustachian tube foreign body. Use of the endoscope during the surgical removal greatly enhanced the ease and safety of removal. This report also highlights the importance of ear protection with any machining and welding work.

Introduction: Heart failure with low ejection fraction (EF) is a known risk factor for stroke. Low EF is associated with increased risk of thrombus formation and is accompanied with 2 to 3 fold increased risk of stroke. This can happen even in the absence of atrial fibrillation. Hypothesis: Our hypothesis was that size of the stroke will be larger in patients with reduction in EF as compared with cardioembolic strokes in preserved EF. The worse the EF, the more stagnation of blood and poor cardiac output leading higher risk of thrombus formation. It’s also likely that the group with reduced EF form a larger thrombus leading to larger stroke as compared to the group with preserved EF. Methods: For our analysis, we retrospectively reviewed charts for 49 acute ischemic stroke patients without atrial fibrillation. We used transthoracic echocardiogram to determine the EF. There are 25 patients with preserved EF, cutoff > 50%. There were 24 patients in reduced EF group. Both groups were matched for age and cardiovascular risk factors. Infarct volume was manually calculated from T1 MRI using BrainLab software. Results: There is an inverse correlation between EF and infarct volume (r=-.283, p=.048) meaning patients with reduced EF had greater infarct volume. Median infarct volume is higher in reduced EF group (median volume = 36 cm 3 ) compared to patients with preserved EF (median volume = 11 cm 3 ) (p=.117). Conclusions: In our patient’s sample, there seems to be an inverse correlation between EF and size of stroke. Patients with reduced EF were associated with larger strokes. Larger studies need to be performed to establish a correlation.

Introduction/Purpose Mixed Reality (MxR) is an emerging technology that makes seamless connections between virtual space and the real world by superimposing computer-generated information onto the real-world environment. MxR can provide additional information in a more intuitive and natural way than alternative information-delivery methods such as traditional angiographic monitors, holograms, virtual or augmented reality models or 3D printed models. Users are able to experience realistic 3D virtual elements with augmented depth perception and binocular field of view. Newer technology has now allowed for interaction with 3D objects within these virtual environments through the use of hand gestures or hand controllers. The authors describe our preliminary experience with MxR as an adjunct tool to traditional angiographic imaging in the preprocedural workup of patients with complex aneurysms using a novel spatial computer, the Magic Leap One device (Magic Leap, Inc Plantation, Florida) which uses a virtual retinal display, which superimposes 3D computer-generated imagery over real world objects, by projecting a digital light field into the user’s eye. Materials and Methods Tomographic Angiographic (DynaCT) data was imported and segmented to create 3D meshes of the intracranial vasculature. The 3D meshes were then projected into MxR space, allowing the operator to inspect the vasculature using a MxR headset (Magic Leap) as well as interact with the aneurysm and adjacent vessels (handling, rotation, magnification, and sectioning) using hand gestures or hand controllers. Results 3D segmentation of a complex aneurysms was successfully performed and projected into MxR. Conventional and MxR visualization modes were equally effective in identifying and classifying the pathology. MxR visualization allowed the operators to manipulate the dataset to achieve a greater understanding of the anatomy of the parent vessel, the angioarchitecture of the aneurysm, and the surface contours of all visualized structures. Conclusion This preliminary study demonstrates the feasibility of utilizing MxR for preprocedural evaluation in patients with anatomically complex neurovascular disorders. This novel visualization approach may serve as a valuable adjunct tool in deciding patient-specific management, including decisions on prognostication and open surgical and endovascular treatment options. Disclosures G. Deib: None. D. Smith: None. B. Chaudhary: None. S. Boo: None. A. Tarabishy: None. J. Carpenter: None. A. Rai: None.

The aim of this study was to assess whether offering local endovascular stroke therapy (EST) rather than transferring patients off-site to receive EST would improve outcomes.There are limited data to determine whether offering EST on-site rather than transferring patients to receive EST off-site improves clinical outcomes.A large academic consortium database was queried to identify patients with acute ischemic stroke who received EST between October 2015 and September 2019. Primary endpoints were in-hospital mortality and poor functional outcomes. Secondary endpoints were major complications, length of stay, and cost. Baseline characteristics were adjusted for using propensity score matching and multivariate risk adjustment.A total of 22,193 patients with acute ischemic stroke who underwent EST (50.8% on-site, 49.2% off-site) were included. Mean ages were 67.9 ± 15.5 years and 68.4 ± 15.5 years, respectively (p = 0.03). In the propensity score matching analysis, mortality and poor functional outcomes were higher in the off-site EST group (14.7% vs. 11.2% and 40.7% vs. 35.9%, respectively; p 0.001). In the risk-adjusted analyses with different models, in-hospital mortality and poor functional outcomes remained significantly higher in the off-site EST group. In the most comprehensive model (adjusting for age, sex, demographics, risk factors, tissue plasminogen activator use, and institutional EST volume), in-hospital mortality and poor functional outcomes were significantly higher in the off-site EST group, with odds ratios of 1.38 (95% confidence interval: 1.26 to 1.51) and 1.26 (95% confidence interval: 1.18 to 1.34), respectively (p 0.001). The incidence of intracranial hemorrhage and mechanical ventilation was higher in the off-site group, but cost was higher in the on-site group in both the propensity score matching and risk-adjusted analyses.In contemporary U.S. practice, patients with acute ischemic stroke treated with EST on-site had lower in-hospital mortality and better functional outcomes compared with those transferred off-site for EST.

A 79-year-old woman with diabetes, prior coronary bypass, renal insufficiency, morbid obesity, and severe symptomatic aortic stenosis presented electively for transcatheter aortic valve replacement (TAVR). Cerebral embolic protection was not used, because of the absence of right radial pulse. The

Treatments for pulmonary embolism are numerous and often complex. Current data on surgical thrombectomy are important but are not readily available. We studied the National Inpatient Sample to evaluate trends in the performance rates and outcomes of surgical thrombectomy in the United States from 2003 through 2014. We think that our findings have meaningful application to the triage and risk stratification of patients who have hemodynamically significant pulmonary embolism.

Background and Purpose— Data on the incidence and outcomes of acute myocardial infarction (AMI) complicating acute ischemic stroke (AIS) are limited. We aim to evaluate the incidence, treatment patterns, and outcomes of AMI in patients with AIS using a nationwide database. Methods— The National Inpatient Sample was used to identify patient with AIS between 2003 and 2014. Trends of incidence of AMI and its associated in-hospital mortality were evaluated. Univariate and multivariate logistic regressions were used to evaluate predictors of AMI. The impact of AMI on in-hospital outcomes was assessed in a comparative analysis of propensity-matched groups of patients with and without AMI. Results— Patients with AIS (n=864 043) were identified in the national inpatient sample, of whom 13 573 patients (1.6%) had an AMI (79.5% non–ST-segment–elevation myocardial infarction and 20.5% ST-segment–elevation myocardial infarction). In-hospital mortality was 21.4% and 7.1% in propensity-matched cohorts of patients with and without AMI, P P Conclusions— AMI complicating stroke carries a substantial in-hospital mortality and cost of care. Patients who underwent coronary angiography with or without intervention may have improved survival although it was only utilized in a minority of patients. Further studies needed to discern the ideal approach in AMI in patients with AIS.

BackgroundM2 occlusions may result in poor outcomes and potentially benefit from endovascular therapy. Data on the rate of M2 strokes is lacking.MethodologyPatients with acute ischemic stroke discharged over a period of 3 years from a tertiary level hospital in the ‘stroke belt’ were evaluated for M2 occlusions on baseline vascular imaging. Regional and national incidence was calculated from discharge and multicounty data.ResultsThere were 2739 ICD-9 based AIS discharges. M2 occlusions in 116 (4%, 95% CI 3.5% to 5%) patients constituted the second most common occlusion site. The median National Institute of Health Stroke Scale (NIHSS) score was 12 (IQR 5–18). Good outcomes were observed in 43% (95% CI 34% to 53%), poor outcomes in 57% (95% CI 47% to 66%), and death occurred in 27% (95% CI 19% to 37%) of patients. Receiver operating characteristics curves showed the NIHSS to be predictive of outcomes (area under the curve 0.829, 95% CI 0.745 to 0.913, p3 for NIHSS score ≥9 versus 30 (±34)cm3 for NIHSS score ConclusionM2 occlusions can present with serious neurological deficits and cause significant morbidity and mortality. Patients with M2 occlusions and higher baseline deficits (NIHSS score ≥9) may benefit from endovascular therapy, thus potentially expanding the category of acute ischemic strokes amenable to intervention.

Objective: The objective of this work was to assess the ability of peripheral blood cell-free DNA (cfDNA) levels to identify ischaemic stroke early in the acute phase of care, as well as to examine the relationship between peripheral blood cfDNA levels and stroke-induced innate immune system activation. Methods: Upon emergency department admission, peripheral blood samples were obtained from 43 patients experiencing acute ischaemic stroke and 20 patients identified as stroke mimics. Plasma cfDNA levels were measured using quantitative polymerase chain reaction (qPCR), infarct volume and NIH stroke scale (NIHSS) were used to assess injury severity, and peripheral blood neutrophil count was used as a measure of innate immune system status.Results: Peripheral blood cfDNA levels were significantly elevated in patients suffering stroke relative to those diagnosed as stroke mimics, and could differentiate between groups with 86% (95% CI = 72–95%) sensitivity and 75% (95% CI = 51–91%) specificity. Furthermore, cfDNA levels displayed significant positive associations between both infarct volume and peripheral blood neutrophil count within the stroke group. Conclusions: These findings suggest that assessment of peripheral blood cfDNA levels may be useful for the identification of ischaemic stroke in the acute care setting, and provide associative evidence that cfDNA is a potential activator of the peripheral innate immune system in response to cerebral ischaemia.

Aorto-atrial fistulas are rare complications of aortic valve replacement. We report a case of a post-aortic valve replacement aorto-atrial fistula that was closed percutaneously with an Amplatz Ductal Occluder-II device.

Sinusitis is commonly seen by both otolaryngologists and primary care physicians who treat pediatric patients. Judicious use of radiation is especially important in this population. When sinusitis is acute and uncomplicated, there is no indication for imaging. There are several clinical situations which may prompt consideration of imaging including persistent or chronic sinusitis and before a planned sinus surgery. In these situations, a non-contrasted CT is appropriate. Complicated sinusitis or concern for malignancy may prompt consideration of other imaging modalities. Caution must be used in interpreting the incidental finding of sinusitis on CT or MRI obtained for other clinical indications, as sinus changes are exceedingly common in asymptomatic patients. Here we discuss the indications for imaging and considerations for choice of imaging modality. We then highlight imaging findings in chronic and complicated sinusitis and discuss specific imaging changes found in cystic fibrosis and allergic fungal sinusitis. This chapter reviews the use of imaging in pediatric patients with sinusitis and the most common imaging findings.

Objective To report the feasibility of a combined imaging and treatment strategy for acute ischemic stroke (AIS) utilizing a hybrid CT-Angiography suite. Methods A descriptive case report covering the technical aspects of whole-brain vascular and perfusion imaging with a single intra-aortic injection of 7 ml of iodinated contrast for suspected large vessel occlusion (LVO). Results A middle-aged man was transferred after 20-hours with a suspected LVO on imaging. The NIHSS was 12 with right sided hemiplegia and slurred speech. A 5F pigtail catheter was placed in the aortic arch in the hybrid interventional (AlphenixTM) and CT (GenesisTM Aquilion One) suite (Canon Medical Systems, Tustin, CA). A 2-second, intra-aortic injection was performed with 20 ml of 30% contrast-saline mixture at 10 ml/s. Simultaneous triggering of the continuous CT volumetric acquisition was performed with a peak of 80 KVP at a constant 320 mAmp. Volumetric angiography reconstruction of the data set was performed at 0.3s interval (320 images, 0.5 mm thickness with 16cm of coverage). The 12-second single acquisition generated a non-contrast CT of the brain, multiphase angiography at 3 frames/second and whole-brain perfusion imaging (figure 1). The non-contrast CT showed patchy infarcts. The angiography showed a sub-occlusive left MCA thrombus with good collaterals. The perfusion imaging showed matched defects corresponding to the infarcts but no significant penumbral tissue. A standard selective left internal carotid artery catheter angiography confirmed the sub-occlusive thrombus and good collaterals. Repeat on table clinical exam had improved from admission. Given the sub-occlusive thrombus, good collaterals and no at-risk ischemic tissue on perfusion – thrombectomy was not performed. Conclusion Rapid assessment of suspected LVO with simultaneous treatment is feasible in select stroke patients, e.g. transfers, using a hybrid CT-Angiography suite and direct intra-aortic diluted contrast injection. An intra-arterial injection gives superior signal-to-noise ratio and temporal resolution than intravenous injection. Immediate thrombectomy following the acquisition in the same room can shorten door to recanalization times. Disclosures A. Rai: 2; C; Stryker, Microvention, Cerenovus. A. Tarabishy: None. S. Boo: 2; C; STRYKER.

Optimizing management of intracranial atherosclerosis is an evolving aspect of neurovascular care in which medical management remains the mainstay of treatment. Endovascular therapy is reserved for patients who fail best medical management with adequate control of associated risk factors and despite dual antiplatelet therapy. Primary submaximal angioplasty is a safe first-line endovascular treatment followed by stenting if necessary.

BackgroundData on large vessel strokes are important for resource allocation and infrastructure development.ObjectiveTo determine an annual incidence of large vessel occlusions (LVOs) and a thrombectomy eligible patient population.MethodsAll patients with acute ischemic stroke discharged over 3 years from a tertiary-level hospital serving a large geographic area were evaluated for an LVO (M1, internal carotid artery terminus, basilar artery). The incidence of LVO was determined for the hospital's 4-county primary service area (PSA, population 210 000) based on each county's discharges and extrapolated to the US population. ‘Thrombectomy eligibility’ for anterior circulation LVOs was based on time (onset Results1157 patients were discharged from the hospital's PSA, of whom 129 (11.1%, 95% CI 9.5% to 13.1%) had an LVO. This translated into an LVO incidence of 24 per 100 000 people per year (95% CI 20 to 28). 20 per 100 000 people per year had anterior circulation LVOs (95% CI 19 to 22), of whom 10/100 000/year (95% CI 8 to 11) were ‘thrombectomy eligible’. An additional 5/100 000/year (95% CI 3 to 6) presented with favorable ASPECTS after 6 hours of symptom onset. Basilar occlusion incidence was estimated at 4/100 000/year (95% CI 2 to 5). These rates yield 77 569 (95% CI 65 835 to 91 091) new LVOs per year in the USA. An estimated 10 284 mechanical thrombectomy procedures were performed in 2015.ConclusionsThis study estimates an LVO incidence of 24 per 100 000 person-years (95% CI 20 to 28). A current estimated annual thrombectomy rate of three procedures per 100 000 people indicates significant potential increase in the volume of endovascular procedures and the need to develop systems of care.

Stereotactic radiosurgery has long been recognized as the optimal form of management for high-grade arteriovenous malformations not amenable to surgical resection. Radiosurgical plans have generally relied upon the integration of stereotactic magnetic resonance angiography (MRA), standard contrast-enhanced magnetic resonance imaging (MRI), or computed tomography angiography (CTA) with biplane digital subtraction angiography (DSA). Current options are disadvantageous in that catheter-based biplane DSA is an invasive test associated with a small risk of complications and perhaps more importantly, the two-dimensional nature of DSA is an inherent limitation in creating radiosurgical contours. The necessity of multiple scans to create DSA contours for radiosurgical planning puts patients at increased risk. Furthermore, the inability to import two-dimensional plans into some radiosurgery programs, such as Cyberknife TPS, limits treatment options for patients. Defining the nidus itself is sometimes difficult in any of the traditional modalities as all draining veins and feeding arteries are included in the images. This sometimes necessitates targeting a larger volume, than strictly necessary, with stereotactic radiosurgery for treatment of the AVM. In this case report, we show the ability to use a less-invasive and three-dimensional form of angiography based on time-lapsed CTA (4D-CTA) rather than traditional DSA for radiosurgical planning. 4D-CTA may allow generation of a series of images, which can show the flow of contrast through the AVM. A review of these series may allow the surgeon to pick and use a volume set that best outlines the nidus with least interference from feeding arteries or draining veins. In addition, 4D-CTA scans can be uploaded into radio-surgery programs and allow three-dimensional targeting. This is the first reported case demonstrating the use of a 4D CTA and an MRI to delineate the AVM nidus for Gamma Knife radiosurgery, with complete obliteration of the nidus over time and subsequent management of associated radiation necrosis with bevacizumab.

BackgroundDelays in delivering endovascular stroke therapy adversely affect outcomes. Time-sensitive treatments such as stroke interventions benefit from methodically developed protocols. Clearly defined roles in these protocols allow for parallel processing of tasks, resulting in consistent delivery of care.ObjectiveTo present the outcomes of a quality-improvement (QI) process directed at reducing stroke treatment times in a tertiary level academic medical center.MethodsA Six-Sigma-based QI process was developed over a 3-month period. After an initial analysis, procedures were implemented and fine-tuned to identify and address rate-limiting steps in the endovascular care pathway. Prospectively recorded treatment times were then compared in two groups of patients who were treated ‘before’ (n=64) or ‘after’ (n=30) the QI process. Three time intervals were measured: emergency room (ER) to arrival for CT scan (ER–CT), CT scan to interventional laboratory arrival (CT–Lab), and interventional laboratory arrival to groin puncture (Lab–puncture).ResultsThe ER–CT time was 40 (±29) min in the ‘before’ and 26 (±15) min in the ‘after’ group (p=0.008). The CT–Lab time was 87 (±47) min in the ‘before’ and 51 (±33) min in the ‘after’ group (p=0.0002). The Lab–puncture time was 24 (±11) min in the ‘before’ and 15 (±4) min in the ‘after’ group (pConclusionsA protocol-driven process can significantly improve efficiency of care in time-sensitive stroke interventions.

CD163 is a scavenger receptor expressed on innate immune cell populations which can be shed from the plasma membrane via the metalloprotease ADAM17 to generate a soluble peptide with lympho-inhibitory properties. The purpose of this study was to investigate CD163 as a possible effector of stroke-induced adaptive immune system suppression. Liquid biopsies were collected from ischemic stroke patients (n = 39), neurologically asymptomatic controls (n = 20), and stroke mimics (n = 20) within 24 hours of symptom onset. Peripheral blood ADAM17 activity and soluble CD163 levels were elevated in stroke patients relative to non-stroke control groups, and negatively associated with post-stroke lymphocyte counts. Subsequent in vitro experiments suggested that this stroke-induced elevation in circulating soluble CD163 likely originates from activated monocytic cells, as serum from stroke patients stimulated ADAM17-dependant CD163 shedding from healthy donor-derived monocytes. Additional in vitro experiments demonstrated that stroke-induced elevations in circulating soluble CD163 can elicit direct suppressive effects on the adaptive immune system, as serum from stroke patients inhibited the proliferation of healthy donor-derived lymphocytes, an effect which was attenuated following serum CD163 depletion. Collectively, these observations provide novel evidence that the innate immune system employs protective mechanisms aimed at mitigating the risk of post-stroke autoimmune complications driven by adaptive immune system overactivation, and that CD163 is key mediator of this phenomenon.

Background It is well known that hyperglycemia is induced by ischemic stroke and causes detrimental outcomes. Hyperglycemia causes neurons to become stunned with the subsequent arrest of protein synthesis and mitochondrial activity. This arrest can lead to cell death following ischemia. What is unknown however is whether normoglycemia following thrombectomy is protective. We proposed that normoglycemia (blood glucose Methods A retrospective cohort study was performed with 187 patients admitted to Ruby Memorial Hospital for acute ischemic stroke and who underwent thrombectomy intervention with or without tPA. Baseline NIHSS and mRS were collected as well diabetes status at time of admission. Glucose levels were recorded within the first 12 hours following thrombectomy. 90 day outcome was grouped into favorable or non-favorable. Analysis was formed by χ2 analysis and student t-tests with p Results Normoglycemia following thrombectomy is an independent risk for favorable 90 day outcome χ2=10.716, p=0.001. The average blood glucose level within 12 hours following thrombectomy for the favorable outcome group was 117 whereas it was 140 for the poor outcome group (t=3.2, p=0.0017). Interestingly, patients with diabetes were not statistically different than patients without diabetes on 90 day outcome results χ2=0.763, p=0.382. 36% of patients with diabetes had favorable outcomes whereas 43.22% of patients without diabetes had favorable outcomes. 91 patients were successfully recanulized and 57.14% had favorable outcomes compared to the 18.87% in the non-recanulized group χ2=21.214, p Conclusions Normoglycemia is an important marker following thrombectomy. If patients have normoglycemia following thrombectomy and recanculization, they are likely to have a favorable long-term course. Hyperglycemia following thrombectomy however is an indication of poor future outcome. Further studies are warranted to elucidate the validity of normoglycemia as a marker for long-term favorable outcome following thrombectomy. Disclosures B. Lucke-Wold: None. S. Boo: None. J. Carpenter: None. A. Tarabishy: None. A. Rai: None.

Background: Several cadaveric studies demonstrate reliable localization of the transverse sinus and the transverse sigmoid junction (TSJ). These studies use the line drawn from the inion to the posterior root of the zygoma (IZ) and the asterion, respectively. We investigated how the size difference between the right and left transverse sinuses (TS) and sigmoid sinuses (SS) affected the accuracy of their respective superficial landmarks, particularly with regards to where this relationship may result in unsafe and/or complicated surgical access. Methods: We utilized Vitrea software to render three-dimensional images based on computed tomographic angiography (CTA). We measured the relationship between the TS and SS to their respective superficial landmarks. Results: We analyzed 50 patients in this study. The distal TS was found caudal to the inion-to-zygoma (IZ) line on average by 5.0 ± 4.3 mm on the right and 6.4 ± 9.3 mm on the left. The mid TS was found cranial on average 3.5 ± 5.7 mm on the right and 3.2 ± 6.0 mm cranial on the left to the superior nuchal line (SNL). The distance from the asterion to the SS was 11.5 ± 2.4 mm medial on the right and 12.1 ± 4.4 mm medial on the left. The average distance was greater on the left than the right when using the IZ landmark. This was directly proportional to the size difference of the sinuses (r2 = 0.15, P = 0.03). Conclusions: Statistically significant differences between the right and left TS and SS were seen in terms of size. This appeared to correlate nicely to the differences observed between the locations of the TSs’ and their respective superficial landmarks.

BackgroundLimited efficacy of IV recombinant tissue plasminogen activator (rt-PA) for large vessel occlusions (LVO) raises doubts about its utility prior to endovascular therapy.PurposeTo compare outcomes and hospital costs for anterior circulation LVOs (middle cerebral artery, internal carotid artery terminus (ICA-T)) treated with either primary endovascular therapy alone (EV-Only) or bridging therapy (IV+EV)).MethodsA single-center retrospective analysis was performed. Clinical and demographic data were collected prospectively and relevant cost data were obtained for each patient in the study.Results90 consecutive patients were divided into EV-Only (n=52) and IV+EV (n=38) groups. There was no difference in demographics, stroke severity, or clot distribution. The mean (SD) time to presentation was 5:19 (4:30) hours in the EV-Only group and 1:46 (0:52) hours in the IV+EV group (pConclusionsIV rt-PA did not improve recanalization, thrombectomy efficacy, functional outcomes, or length of stay. Combined therapy was associated with significantly higher total and direct hospital costs than endovascular therapy alone.

Background M2 occlusions have typically been excluded from endovascular stroke trials. However variations in the size of the MCA branches and the area of brain they supply runs the risk of excluding a dominant trunk supplying a large part of the brain and hence resulting in a significant ischemic injury. Perfusion imaging allows a more functional depiction of the vascular territory and maybe more relevant for endovascular selection. Objective To determine the rate of M2 occlusions amongst all hospital discharges for acute ischemic stroke (AIS) and to functionally classify occlusion severity based on baseline perfusion imaging and final infarct volume. To secondarily extrapolate this rate to the national inpatient sample (NIS) database for estimating the annual burden of M2 occlusions that may benefit from endovascular therapy. Methodology All hospital discharges for AIS (ICD-9 codes 433.xx, 434.xx 435.xx) over a 3 year period from a large rural hospital system were screened for an M2 occlusion based on admission imaging. These were classified into the superior or inferior trunk based on anatomy and dominant or non-dominant division based on size. The occlusion severity was graded on time-to-peak (TTP) perfusion imaging as a proportion of the entire MCA. Infarct volume on follow up imaging represented the final ischemic injury. The results were extrapolated to the NIS-database. Results Out of 2757 AIS hospital discharges 118 (4.3%) patients were identified with an M2 occlusion. 71 (60.2%) of these patients presented within 6 hours and 47 (39.8%) after 6 hours of last seen normal (LSN). Baseline perfusion (TTP) and follow-up imaging was available for 75 patients. The superior trunk (ST) was involved in 36 (48%) and the inferior trunk (IT) in 39 (52%) patients. In 27 (75%) patients with ST involvement, it was the dominant division versus 36 (92.3%) patients with IT occlusion had it as the dominant division (p = 0.037). Overall a dominant division was occluded in 63 (84%) patients and a non-dominant in 12 (16%) patients. In 47 (74.6%) patients with a dominant branch occlusion (ST or IT) the TTP abnormality was >1/3 rd of the MCA distribution versus 5 (41.7%) patients with a non-dominant branch occlusion that had >1/3 rd MCA involvement (p = 0.02). Patients with a dominant branch occlusion had a final infarct volume of 49.6 cm 2 (±46.3) versus a volume of 16.7 cm 2 (±13.8) for non-dominant occlusions (p = 0.009). In patients with >1/3 rd MCA involvement on TTP images the infarct volume was 51.5 cm 2 (±47.6) versus an infarct volume of 28.1 cm 2 (±31.5) in patients with ≤1/3 rd MCA abnormality (p = 0.03). There were 1,135,030 AIS discharges nationally for 2013 for the same ICD-9 codes. A 4% rate of M2 occlusions yields 45,401 potential patients with an M2 occlusion of which 38,137 can have a dominant branch involvement and hence the risk of significant ischemic injury. Conclusion Patients with a dominant branch occlusion, whether superior or inferior, had larger TTP abnormalities (>1/3 rd MCA) and final infarct volumes. An estimated 37,137 AIS patients can have a dominant M2 occlusion with significant risk of ischemic injury. A functional as opposed to pure anatomical classification may allow selecting these patients for endovascular therapy. Disclosures A. Rai: 1; C; Stryker Neurovascular. 2; C; Stryker Neurovascular. A. Tarabishy: None. P. Link: None. S. Boo: None. N. Lucke-Wold: None. J. Domico: None. J. Carpenter: None.

Background and purpose Delays in delivering endovascular stroke therapy adversely impact outcomes. Time-sensitive treatments such as stroke interventions benefit from methodically developed protocols. Clearly defined roles in these protocols allow for parallel processing of tasks resulting in consistent delivery of care. The paper presents the outcomes of a quality-improvement (QI) process directed at reducing stroke treatment times in a tertiary level academic medical center. Methods A six-sigma based QI-process was developed over a 3 month period. After an initial analysis, procedures were implemented and fine-tuned to identify and address rate-limiting steps in the endovascular care pathway. Prospectively recorded treatment times were then compared in two groups of patients who were treated “Before” (n = 64) or “After” (n = 30) the QI-process. Three time intervals were measured: ER-arrival to CT-scan (ER-CT), CT-scan to interventional lab (CT-Lab) and Interventional lab arrival to groin puncture (Lab-puncture). The ER-CT time was 40(±29)-minutes in the “Before” and 26(±15)-minutes in the “After” group (p = 0.008). The CT-Lab time was 87(±47)-minutes in the “Before” and 51(±33)-minutes in the “After” group (p = 0.0002). The Lab-puncture time was 24(±11)-minutes in the “Before” and 15(±4)-minutes in the “After” group (p Conclusion A protocol driven process can significantly improve efficiency of care in the time-sensitive stroke interventions. Disclosures A. Rai: 1; C; stryker Neurovascular. 2; C; stryker Neurovascular. M. Smith: None. S. Boo: None. A. Tarabishy: None. G. Hobbs: None. J. Carpenter: None.

Background Endovascular therapy has been endorsed for emergent large vessel occlusions (ELVO). However the incidence of ELVO is ill defined and speculative. A methodical estimate of these patients is important for developing systems of care, resource allocation and market projections. Objective To determine the national burden of ELVO by extrapolating these rates from a tertiary rural health system that captures over 85% of all ischemic strokes within its large rural catchment area to the national inpatient sample (NIS) database. Methodology All hospital discharges with a primary or secondary diagnosis of AIS (ICD-9 433.xx, 434.xx, 435.xx) over a 3 year period in a rural tertiary health system in the “stroke-belt” were evaluated for ELVO (ICA-T, MCA, BA) based on admission CT or MR angiography. For anterior circulation strokes, an ASPECTS ≥6 was considered favorable for thrombectomy. The same ICD-9 codes were utilized to query the NIS-database to determine all AIS hospital discharges nationally and the ELVO rates were estimated based on the results from our catchment population. Results There were 2757 AIS hospital discharges over a 3 year period (March 2012 to March 2015) based on the selected ICD-9 codes. An ELVO was present in 324 (11.8%) of these patients. Out of these, M1-occlusion was present in 232 (71.6%), ICA-T in 37 (11.4%) and BA in 55 (17%) patients. The majority of ELVO patients (n = 174, 53.7%) presented within 6 hours of last seen normal (LSN). Of the remaining 150 (46.3%) patients: 45 (13.6%) presented at 6–12 hours, 60 (18.5%) at 12–24 hours and 27 (8.3%) at greater than 24 hours of LSN. There were 19 (5.9%) patients with unknown LSN. For anterior circulation (n = 269, 83%) an ASPECTS ≥6 was observed in 118 of 150 (78.7%) patient presenting within 6 hours of LSN and in 66 of 1119 (55.5%) patients presenting after 6 hours of LSN (p Conclusion Almost 12% of the patients in our large rural sample of AIS hospital discharges presented with an ELVO. This translated to 133,388 patients when extrapolated to the NIS-database for 2013. An estimated 48,579 patients within 6 hours and 27,172 patients after 6 hours could be thrombectomy eligible based on ASPECTS ≥6. An additional 22,643 patients were estimated to have a basilar occlusion. These are estimates based on a stroke center within a healthcare system serving a large rural population and probably represent the upper limit since the area under study has one of the highest ischemic stroke rates in the country. These numbers can also be subject to regional variations but nonetheless serve as a starting point for estimating the ELVO stroke burden and for planning systems of care. Disclosures A. Rai: 1; C; Stryker Neurovascular. 2; C; Stryker Neurovascular. P. Link: None. S. Boo: None. J. Domico: None. N. Lucke-Wold: None. A. Tarabishy: None. J. Carpenter: None.

Introduction As aneurysm treatment transitions towards flow-diversion, coils may become less important. This coupled with the emphasis on healthcare economics requires an assessment of the coil types that may be pertinent in future. We hypothesised that larger coils provide the biggest “bang for the buck” in occluding aneurysms and hence may be more relevant than smaller, shorter coils. Methodology A retrospective analysis was performed on 402 aneurysms. Aneurysm were divided into: 11 mm (n = 54). Coil-thickness was dichotomized into ≤0.0115” and >0.115”. An analysis of aneurysms with 100% use of either ≤0.0115” or >0.115” coils was performed for each group. The effect of “framing” coils on the final packing density (PD) was also calculated. The financial impact of coil choice was factored into each aneurysm treatment. Results The mean age was 57.5(±12) years and there were 320(79.6%) female patients. The mean PD was 25%(±13). The PD was 30%(±15) for the 11 mm-group (p 0.0115”(n = 160), the PD was 27.4%(±15), (p = 0.002). The final PD was 26%(±14) if the first or “framing” coil was >0.0115 (n = 251), versus a PD of 23%(±11) if the framing coil was ≤0.0115” (n = 148), (p = 0.03). The final PD rose to 27%(±14) if the first two coils were >0.0115 (n = 212), versus a PD of 23%(±11) if the first two coils were ≤0.0115” (n = 172), (p = 0.01). The impact of coil choice (all coils ≤0.0115” versus all coils >0.0115) on PD, number of coils deployed and cost of coils for aneurysms 0.0115”. For aneurysms between 6–11 mm, there was no significant difference in PD based on coils used, however to achieve a similar PD, significantly more coils at a significantly higher cost had to be used in the ≤0.0115” group. Conclusion Flow-diverters are approved for large aneurysms. The potential next target for these devices is aneurysms between 6–11 mm and perhaps smaller. The question is what function coils may have in this emerging era? A potential use is in conjunction with endo-luminal devices – an adjunctive rather than a primary role. If PD is a measure of aneurysm occlusion than certainly coils larger than 0.0115 fare better in either achieving a higher PD than smaller coils or a similar PD with less number of coils and at a reduced cost. This effect is evident even if only the framing coils are >0.0115. We can thus speculate that smaller OD coils will increasingly become irrelevant as the field evolves. Disclosures A. Rai: 2; C; Stryker Neurovascular, Codman Neuro. B. Cline: None. J. Patterson: None. A. Tarabishy: None. J. Carpenter: None.

We have previously described a unique gene expression signature exhibited by synovial fluid leukocytes in response to bacterial infection, identifying a number of potential biomarkers for infection. However, the diagnostic performance of these potential biomarkers in an immunoassay format is unknown. We therefore evaluated the sensitivity, specificity, and accuracy of several potential synovial fluid biomarkers for infection, and compared them to current standards of testing for periprosthetic infection. We prospectively collected synovial fluid from 14 patients classified as having a periprosthetic infection and 37 patients classified as having an aseptic failure. The synovial fluid samples were tested for 23 potential biomarkers for periprosthetic infection. We then determined differences in biomarker levels between infected and aseptic groups, then computed the sensitivity, specificity, positive predictive value, negative predictive value and accuracy for select biomarkers, and finally compared those to current standard tests for infection. Twelve synovial fluid biomarkers had substantially higher average levels in the synovial fluid of infected versus aseptic patients. Synovial fluid levels of IL-1 were a mean of 258 times higher in patients with a periprosthetic infection compared to patients having revision for aseptic diagnoses. Synovial fluid IL-1 and IL-6 levels correctly classified all patients in this study with a sensitivity, specificity, positive predictive value, negative predictive value and accuracy equal to 1. Several markers tested in this study outperformed the ESR and CRP tests. Patients with a periprosthetic infection have elevated levels of numerous synovial fluid biomarkers, when compared to patients with aseptic diagnoses. Several of these biomarkers exhibited nearly ideal sensitivity, specificity, and accuracy in this study, suggesting that synovial fluid biomarkers could be a valuable tool for diagnosing periprosthetic infection. Level III, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.

Previous studies show that total knee replacement (TKR) patients have difficulty performing certain tasks involving deep knee flexion which are part of activities of daily living (ADL). Muslims’ lifestyles heavily depend on the ability to fully flex the knee, and many daily activities, such as praying, social encounters (attending the Sheikh’s majlis), dining or even using the hole bathroom, are carried out on the ground. The LPS Flex implant has been designed to accommodate this by giving up to 165 degrees of flexion. One-thousand and thirty-two (1032) TKRs were performed on patients diagnosed with osteoarthritis using the LPS Flex mobile bearing implant over a five year period with a minimum of 1 year post-operative follow up. The results were then compared to a series obtained from the Zimmer Feedback database which is managed independently by the Audit and Research Office, Department of Orthopaedic and Trauma Surgery, University of Dundee, Dundee, Scotland, United Kingdom. 44% of pre-op cases had full flexion as per our set criteria. There were no apparent differences in patello-femoral pain levels, complications or Knee Society score despite the fact that our patients had, on average, an increase in maximum flexion along with an increase in functional ability. The knee score failed to assess this improved functionality of patients who had full flexion; a new diagnostic method is therefore needed. The results indicate that the implant allows patients to maintain a high degree of flexion and function post-operatively, with few complications.

Background Coiling remains the current primary therapy for aneurysms. Understanding the economics of coiling will establish a framework against which the financial impact of future devices may be measured. Methodology A retrospective analysis of 542 aneurysm coilings was performed. Of these, financial-data was available on 377 patients. This included the DRG-code, hospital charges, total-cost, implant-cost, payments received, the payer and the length of stay for each admission. Treatment parameters included aneurysm size, type and number of coils, and use of adjunctive devices. We hypothesised that aneurysm size, rupture-status, number of coils and adjunctive devices would impact the financial outcome. Results 235(62.3%) aneurysms were treated electively while 142(37.7%) were ruptured. The length of stay was 2.5(±5) days for elective and 17.7(±13) days for ruptured aneurysms (p 11 mm group. The number of coils/aneurysm was 4.1(±2.8) for the 11 mm-group, (p The mean payments by payer (Figure 1) and the difference between total-cost and payments by payer (Figure 2) show that apart from Blue Cross/Blue Shield and Commercial insurance, every other payer averaged a net loss-for the hospital. There was no impact of the rupture status, age, gender, aneurysm size, use of adjunctive device on the net deficit to the hospital. Conclusion In our Medicare/Medicaid heavy population, the payer-mix was an overwhelmingly significant financial determinant in aneurysm treatment. Contrary to our hypothesis, none of the other factors impacted the average net deficit that the hospital suffered in these cases. Disclosures A. Rai: 2; C; Stryker Neurovascular, Codman Neuro. A. Tarabishy: None. B. Cline: None. J. Patterson: None. S. Boo: None. J. Carpenter: None.

Introduction If flow-diverters are to become the preferred mode of treating aneurysms then other than their efficacy, an analysis of their financial impact against coiling is warranted. Methodology An IRB approved retrospective analysis was performed on 500 aneurysms treated in 427 patients. The implant-cost was calculated based on the number and type of coils that were deployed, coils that were opened but not deployed, and use of any adjunctive devices. Total aneurysm-cost included all re-treatments. The aneurysms were divided into 11 mm-groups. Aneurysm-costs were compared with the hospital9s cost for a flow-diverter (PipelineTM-$12,500). An analysis was performed to determine a cost-point based on aneurysm size, and use of adjunctive devices at which a flow-diverter became economically superior to coiling. This analysis was repeated for a hypothetically reduced price of the flow-diverter. Results The total implant-cost per case was $11,447(±$7523). The number of coils had a strong, positive correlation with the implant-cost (R20.8, p 11 mm but was significant in the other groups. The use of flow-diverter was economically better than coils in all aneurysms >11 mm, in all aneurysms between 6–11 mm that required an adjunctive device and in all aneurysms Conclusion The implant-cost is affected by number of coils, aneurysm-size and treatment type. A flow-diverter may be economically feasible in aneurysms >11 m, aneurysms between 6–11 mm that require an adjunctive device and aneurysms Disclosures A. Rai: 2; C; Stryker Neurovascular, Codman Neuro. B. Cline: None. A. Tarabishy: None. J. Patterson: None. S. Boo: None. J. Carpenter: None.