Mechanical Revascularization in the Era of the Field Assessment Stroke Triage for Emergency Destination (FAST-ED): A Retrospective Cohort Assessment in a Community Stroke Practice.

BACKGROUND: Endovascular mechanical revascularization has become the mainstay acute stroke management secondary to emergent large vessel occlusions. In patients who can benefit from mechanical revascularization, the ability to intervene in a timely manner directly correlates with improved outcomes. The field assessment for stroke triage (FAST-ED) prehospital triage tool, is one of many stroke severity scales designed to decrease time to diagnosis in the field and optimize patient triage to comprehensive stroke centers. It is however unclear what impact if any, this tool has on time to activation of hospital stroke intervention teams. We set out to assess the impact of the implementation of the FAST-ED triage tool on the activation of the stroke intervention team in a community stroke treatment practice. METHODS: We retrospectively reviewed institutional records for consecutive admissions with reported stroke alerts between March 2017 and September 2018, and selected patients who presented via Emergency Medical Services (EMS). The association between FAST-ED scores and impact on time to revascularization as well as the association between FAST-ED scores and the presence of emergent large vessel occlusion were analyzed. RESULTS: There was a statistically significant improvement in interventional team activation times in favor of the FAST-ED cohort, (P < .05). CONCLUSIONS: FAST-ED implementation demonstrates a statistically significant improvement on stroke team activation times for patients who are candidates for mechanical revascularization. Larger cohort analysis is needed to fully evaluate the magnitude of this effect.

MRI myelography for diagnosis and targeted blood patching of multilevel thoracic spine CSF leaks: Report of 2 cases.

In patients with occult cerebrospinal fluid (CSF) leaks or CSF leak syndrome, orthostatic headaches are a common presenting symptom. Although computed tomography (CT) myelography has historically been the gold standard for diagnosis with radioisotope cisternography as a diagnostic alternative, magnetic resonance imaging (MRI) myelography using intrathecal gadolinium has reported sensitivity of 80%-87%. Two patients with spontaneous orthostatic headaches lasting for several days were diagnosed with CSF leaks at multiple thoracic segments using MRI myelogram with intrathecal gadolinium (Gadavist, Bayer, Whippany, NJ). This allowed for subsequent targeted treatment with CT fluoroscopy guidance, resulting in therapeutic responses within 1-2 treatment with targeted blood patching. Although intrathecal gadolinium is an off-label use, the superior contrast resolution and lack of radiation exposure makes MRI myelography an excellent imaging modality for diagnosing CSF leak, targeting treatment, and monitoring outcomes compared to CT myelography and radioisotope cisternography.

Functional Independence After Stroke Thrombectomy Using Thrombolysis In Cerebral Infarction Grade 2c: A New Aim of Successful Revascularization.

BACKGROUND: Within the Thrombolysis In Cerebral Infarction (TICI) classification, TICI 2b has been historically considered successful recanalization. However, TICI 2b may result in worse functional outcomes compared with TICI 3 or a proposed TICI 2c revascularization grade. The aim of this study was to evaluate differences in functional independence at 90 days between TICI 2b, 2c, and 3 grades. METHODS: A retrospective review of 185 consecutive patients with anterior cerebral circulation occlusions was performed; 33 patients who were treated >8 hours after onset were excluded. Patient angiograms were graded by 2 experienced neurointerventional physicians. Baseline demographics and functional independence at 90 days were compared. RESULTS: Of 152 patients included in the study, 113 patients achieved TICI grade 2b (n = 37), 2c (n = 34), or 3 (n = 42). A significant difference in functional independence at 90 days was observed between TICI 2b and 2c/3 (P = 0.0008), between 2b and 2c (P = 0.0005), and between 2b and 3 (P = 0.01). There was no significant difference in functional independence between 2c and 3 (P = 0.24). CONCLUSIONS: TICI 2c revascularization is associated with significantly improved outcomes compared with TICI 2b revascularization and similar outcomes compared with TICI 3 revascularization. Using a TICI grading system that includes an additional TICI 2c grade or expands the current definition of TICI 3 allows for refined prediction of functional independence. Achieving TICI 2c/3 reperfusion should be considered during stroke thrombectomy.

Navien catheter experience in neuroendovascular interventions.

Purpose Advancements in catheter technology have allowed for greater flexibility and trackability. We report 265 consecutive, single-center neurointerventional cases using the Navien guide catheter. Materials and methods Retrospective analysis was performed of consecutive intracranial endovascular procedures utilizing the Navien catheter. Data collected included procedure type, catheters, guide catheter position, cervical access artery tortuosity grade and complications. Results The 5 French catheter was used in 130 cases. The 6 French catheter was used in 135 cases. Access was via the internal carotid artery in 204, external carotid artery in 10, and vertebral artery in 51 cases. Catheter tip position was in the petrous segment of the internal carotid artery in 36.6% (97/265), distal cervical internal carotid artery in 13.9% (37/265), cavernous internal carotid artery in 10.2% (27/265), proximal or mid cervical internal carotid artery in 5.6% (15/265), supraclinoid internal carotid artery in 0.8% (2/265), and intradural vertebral artery in 0.8% (2/265) of cases. Catheter position was not determined in 18.9% (50/265) of cases. Proximal vessel tortuosity (grade B or C) was present in 98 cases (37%), and the catheter was tracked distal to the tortuosity in 93% (91/98) of these cases. The overall success rate without catheter complication was 97% (258/265). The Navien was replaced by another catheter in 1.9% (5/265) of cases. There was one cervical artery dissection (0.4%) and one severe vasospasm (0.4%) necessitating Navien removal. Conclusions The Navien guide catheter provided distal access support for neuroendovascular interventions in nearly all cases, including cases with proximal artery tortuosity, with a low rate of catheter-related complications.

Use of Pipeline Flex is associated with reduced fluoroscopy time, procedure time, and technical failure compared with the first-generation Pipeline embolization device.

BACKGROUND: Flow diversion with the Pipeline embolization device is a well-established method of intracranial aneurysm treatment. However, deployment of the first-generation device (Pipeline Classic) can be technically challenging. The Pipeline Flex contains the same flow-diverting stent with a modified delivery system. OBJECTIVE: To compare procedural outcomes between the first-generation device (Pipeline Classic) and the Pipeline Flex. METHODS: Thirty-eight of the first 40 consecutive patients who underwent intracranial aneurysm treatment with the Pipeline Flex and 58 of the most recent 60 consecutive patients who underwent treatment with the Pipeline Classic at our institution were evaluated. Patient demographics, aneurysm characteristics, technical procedural details, and early outcomes were analyzed. RESULTS: The two groups were comparable for age, gender, and location of target aneurysms. Use of Pipeline Flex decreased procedure time by 44.2 min (p≤0.001) and fluoroscopy time by 22.0 min (p=0.001) compared with the Pipeline Classic. Similarly, radiation exposure was less in the Flex group with a mean difference of 3473.5 Gy cm2 (p=0.002), while contrast usage was decreased with a mean difference of 22.3 mL (p=0.007). These differences remained significant in multivariate regression analysis. Finally, the rate of device deployment failure was lower in the Flex group (7.1%) than in the Classic group (23.9%) (p=0.034). CONCLUSIONS: Use of Pipeline Flex significantly reduces the total procedure and fluoroscopy time, contrast usage, patient radiation exposure, and proportion of recaptured devices in comparison with the Pipeline Classic, probably owing to an enhanced delivery system that allows for more reliable and controlled deployment.

CT Perfusion Dynamics of Intracranial Tuberculomas.

AIMS: To study perfusion characteristics of intracranial tuberculomas and analyze changes with anti tubercular treatment. MATERIALS AND METHODS: Nineteen patients of histologically proven intracranial tuberculomas were included in the study of which 9 were not on antitubercular treatment and ten were on antitubercular treatment (6 patients on treatment for less than 2 months and 4 were more than 6 months). All patients underwent CT perfusion (CTP) and CTP parameters like rCBV and rCBF were obtained from entire lesion, center and capsule of lesions and compared. RESULTS: CTP parameters like rCBF and rCBV were significantly low in all the three ROIs in the group not on treatment compared to that of on treatment ; rCBF and rCBV of entire lesion (p=0.018 and p=0.005 respectively), capsule (p=0.045 and p=0.010 respectively) and center of the lesion (p=0.020 and p=0.009) respectively). Tuberculomas on antitubercular treatment of more than six months showed reduced rCBF and rCBV in entire lesion (p=0.01 & p=0.01 respectively), capsule (p=0.04 & p=0.03 respectively) and center (p=0.08 & p=0.05 respectively) compared to those on treatment for less than two months. Similarly tuberculomas on treatment for six months did not show significant difference in rCBF and rCBV compared to tuberculomas who were not on treatment. Tuberculomas on treatment for less than two months showed statistically increased rCBF and rCBV in entire lesion (p=0.01 & p=0.04 respectively), capsule (p=0.03 & p=0.01 respectively) and center (p= 0.03 &=0.01) compared to those not on treatment. CONCLUSION: Intracranial tuberculomas not on treatment and those on treatment for around six months show low perfusion and tuberculomas on treatment for less than two months show high perfusion. These findings suggest that serial perfusion profiles of tuberculomas on treatment could possibly be seen as surrogate markers of response to treatment.

Role of dynamic CT perfusion study in evaluating various intracranial space-occupying lesions.

AIMS: Differentiating intracranial mass lesions on CT scan is challenging. The purpose of our study was to determine the perfusion parameters in various intracranial space-occupying lesions (ICSOL), differentiate benign and malignant lesions, and differentiate between grades of gliomas. MATERIALS AND METHODS: We performed CT perfusion (CTP) in 64 patients, with age ranging from 17 to 68 years, having space-occupying lesions in brain and calculated relative cerebral blood flow (rCBF) and relative cerebral blood volume (rCBV). RESULTS: We found significantly lower perfusion in low-grade gliomas as compared to high-grade tumors, lymphoma, and metastases. Similarly in infective lesions, TWT and abscesses showed significantly lower perfusion compared to TOT. In ring enhancing lesions, capsule of TWT showed significantly lower perfusion as compared to abscesses, TOT, and metastases. CONCLUSION: Thus, in conclusion, infective lesions can be differentiated from tumors like lymphomas, high-grade gliomas, or metastases based on perfusion parameters. The cut off value of rCBV 1.64 can be used to differentiate between low grade and high grade gliomas. However, depending only on perfusion parameters, differentiation between the tumors like lymphomas, high-grade gliomas, and metastases may not be possible.

In silico study of low-frequency transcranial ultrasound fields in acute ischemic stroke patients.

Ultrasound in the sub-megahertz range enhances thrombolysis and may be applied transcranially to ischemic stroke patients. The consistency of transcranial insonification needs to be evaluated. Acoustic and thermal simulations based on computed-tomography (CT) scans of 20 patients were performed. An unfocused 120-kHz transducer allowed homogeneous insonification of the thrombus, and positioning based on external landmarks performed similarly to an optimized placement based on CT data. With a weakly focused 500-kHz transducer, the landmark-based positioning underperformed. The predicted inter-patient variation of in situ acoustic pressure was similar with both the 120 and 500-kHz transducers for the optimized placement (18.0-26.4% relative standard deviation). The simulated maximum acoustic pressure in intervening tissues was 2.6 ± 0.6 and 2.0 ± 0.7 times the pressure in the thrombus for the 120-kHz and 500-kHz transducers, respectively. A 1 W/cm(2) insonification of the thrombus caused a 3.8 ± 2.2 °C increase in the bone for the 120-kHz transducer, and a 13.4 ± 3.3 °C increase for the 500-kHz transducer. Contralateral local maxima up to 1.1 times the pressure amplitude in the targeted zone were predicted for the 120-kHz transducer. We established two transducer placement approaches, one based on analysis of a head CT and the other using simple external, visible landmarks. Both approaches allowed consistent insonification of the thrombus.

Energy status and metabolism in intracranial space occupying lesions: a prospective 31p spectroscopic study.

AIM: Intracranial space occupying lesions can be infective or tumour. There are various advanced Magnetic resonance imaging techniques like perfusion, diffusion and proton spectroscopy which can differentiate between them. However, (31) Phosphorus spectroscopy studies the energy status and the metabolism pattern of various tissues and can be used potentially to differentiate between them depending on their Metabolism pattern. Thus, we aimed to study energy status of various intracranial lesions and try to differentiate between them including grades of gliomas. MATERIALS AND METHODS: (31)PMRS was done in 1.5T MRI in 43 patients prior to surgery or through/via stereo-tactic biopsy, of which 25 were men and 18 women with mean age 41.34 y ranging from 7-71 y. Single voxel phosphorus spectroscopy was done from the solid portion of the lesions and data was analysed and post processed. RESULTS: Study includes Lymphoma (n=6), Grade 1 and 2 glioma (n=5), grade 3 glioma (n=9), grade 4 glioma(n=6), metastases (n=5), tuberculoma (n=7) and pyogenic abscesses (n=5). The integral values of PME, Pi, PDE, γ-ATP, α-ATP, ß-ATP with reference to the position of PCr were calculated along with various ratios. Integral values of Pi and PDE were significantly increased in metastases but decreased in gliomas grade 1-2 compared to other pathologic conditions. Mean integral values of LEP (low energy phosphates) and total phosphates were significantly decreased in gliomas grades 1 and 2 and increased in metastases when compared with other pathologic conditions. PCr /Pi was increased in glioma grades 1, 2 and 3 but decreased in metastases; the significance was observed only in gliomas grade 3 and metastases. Metabolic ratios of PDE/ß ATP and Pi/ßATP were decreased in glioma grades 1 and 2 and increased in metastases with statistical significance. CONCLUSION: (31)PMRS may help in differentiating primary from secondary lesions and assess grades of gliomas.

Treatment of cerebral aneurysms-surgical clipping or endovascular coiling: the guiding principles.

Cerebral aneurysms represent common intracranial vascular lesions encountered in neurosurgical practice. The clinical presentation is varied, ranging from asymptomatic lesions to those presenting with catastrophic intracranial hemorrhage. Aneurysm treatment has been a rapidly evolving field with numerous technical innovations, especially in the last two decades. Selecting the appropriate treatment can be a complex process that involves integration of information regarding the patient's clinical presentation, associated comorbidities, the aneurysm's morphological characteristics, safety and efficacy of the treatment options and skill and experience of available practitioners, amongst others. In this article, we review each of these factors and appraise the available scientific evidence in an effort to facilitate decision making in the treatment of cerebral aneurysms. The treatment of intracranial aneurysms is best performed at high volume centers that utilize a multidisciplinary, team-based approach.

Experimental validation of a finite-difference model for the prediction of transcranial ultrasound fields based on CT images.

The prevalence of stroke worldwide and the paucity of effective therapies have triggered interest in the use of transcranial ultrasound as an adjuvant to thrombolytic therapy. Previous studies have shown that 120 kHz ultrasound enhanced thrombolysis and allowed efficient penetration through the temporal bone. The objective of our study was to develop an accurate finite-difference model of acoustic propagation through the skull based on computed tomography (CT) images. The computational approach, which neglected shear waves, was compared with a simple analytical model including shear waves. Acoustic pressure fields from a two-element annular array (120 and 60 kHz) were acquired in vitro in four human skulls. Simulations were performed using registered CT scans and a source term determined by acoustic holography. Mean errors below 14% were found between simulated pressure fields and corresponding measurements. Intracranial peak pressures were systematically underestimated and reflections from the contralateral bone were overestimated. Determination of the acoustic impedance of the bone from the CT images was the likely source of error. High correlation between predictions and measurements (R(2) = 0.93 and R(2) = 0.88 for transmitted and reflected waves amplitude, respectively) demonstrated that this model is suitable for a quantitative estimation of acoustic fields generated during 40-200 kHz ultrasound-enhanced ischemic stroke treatment.