Superior Sagittal Sinus Thrombectomy in Pediatric Head Injury.

INTRODUCTION: Injury and subsequent thrombosis of the cerebral venous sinuses may be caused by closed head injuries secondary to a variety of different mechanisms. Skull fractures can lacerate or otherwise disrupt adjacent dural sinuses. The sequelae of such injuries may include thrombosis and either partial or total occlusion of the sinus, ultimately resulting in significant venous congestion. Sagittal sinus injury is associated with a more serious outcome due to the obligatory flow into the sinus, especially posterior to the coronal suture. In such cases, venous infarction may be a severe and life-threatening complication of head injury. CASE PRESENTATION: A 2-year-old female presented with a depressed skull fracture near the midline and a thrombus in the sagittal sinus. Anticoagulation, the standard treatment cerebral venous sinus thrombosis (CVST), was contraindicated due to intracranial hemorrhage, so immediate thrombectomy was performed with successful neurologic recovery at 9-month follow-up. To our knowledge, this case is the youngest patient documented to receive mechanical thrombectomy for superior sagittal sinus (SSS) thrombosis due to trauma. CONCLUSION: Closed head injuries in pediatric patients may be associated with CVST, with resulting venous drainage compromise and profound neurologic sequelae. Unlike adult patients with spontaneous CVST in which anticoagulation are the standard of care, pediatric patients experiencing traumatic CVST may have contraindications to anticoagulants. If the patient has a contraindication to anticoagulation such as intracranial bleeding, endovascular mechanical thrombectomy may be an effective intervention when performed by an experienced neurointerventionalist.

Antiplatelet and anticoagulation therapy and the risk of pituitary apoplexy in pituitary adenoma patients.

PURPOSE: Pituitary apoplexy can be a life threatening and vision compromising event. Antiplatelet and anticoagulation use has been reported as a contributing factor in pituitary apoplexy (PA). Utilizing one of the largest cohorts in the literature, this study aims to determine the risk of PA in patients on antiplatelet/anticoagulation (AP/AC) therapy. METHODS: A single center, retrospective study was conducted on 342 pituitary adenoma patients, of which 77 patients presented with PA (23%). Several potential risk factors for PA were assessed, including: patient demographics, tumor characteristics, pre-operative hormone replacement, neurologic deficits, coagulation studies, platelet count, and AP/AC therapy. RESULTS: Comparing patients with and without apoplexy, there was no significant difference in the proportion of patients taking aspirin (45 no apoplexy vs. 10 apoplexy; p = 0.5), clopidogrel (10 no apoplexy vs. 4 apoplexy; p = 0.5), and anticoagulation (7 no apoplexy vs. 3 apoplexy; p = 0.7). However, male sex (p-value < 0.001) was a predictor for apoplexy while pre-operative hormone treatment was a protective factor from apoplexy (p-value < 0.001). A non-clinical difference in INR was also noted as a predictor for apoplexy (no apoplexy: 1.01 ± 0.09, apoplexy: 1.07 ± 0.15; p < 0.001). CONCLUSIONS: Although pituitary tumors have a high risk for spontaneous hemorrhage, the use of aspirin is not a risk for hemorrhage. Our study did not find an increased risk of apoplexy with clopidogrel or anticoagulation, but further investigation is needed with a larger cohort. Confirming other reports, male sex is associated with an increased risk for PA.

Utility of Surveillance Angiography in Aneurysmal Subarachnoid Hemorrhage: A Retrospective Study of 223 Consecutive Patients.

BACKGROUND: Patients with aneurysmal subarachnoid hemorrhage (aSAH) who survive the rupture are at risk for delayed neurologic deficits and cerebral infarction. The ideal method(s) of surveillance for cerebral vasospasm, and the link between radiographic vasospasm and delayed neurologic deficits, remain controversial. We instituted a postbleed day 7 angiography protocol with the stated goals of identification of vasospasm, improving neurologic outcomes, and possibly lowering cost of care. METHODS: We conducted a quality improvement project in which we retrospectively analyzed consecutive cases of aSAH from a single institution over a 5-year period. Patients were excluded if they did not receive treatment for their aneurysm or were < 18 years of age. We analyzed demographic and outcome information for patients managed by protocolled angiography versus those who were managed by as-needed endovascular rescue therapy. Statistical tests were performed comparing means and proportions in both cohorts, as appropriate. RESULTS: In total, 223 patients were identified who met inclusion criteria. In total, 157 patients were identified in the protocolled day 7 angiography group, and 66 were in the nonprotocolled angiography group. Demographics were similar between the day 7 angiogram and medical management cohorts, except for a higher mean age among the latter group (p = 0.016). The protocolled angiography group underwent a significantly greater number of angiograms (p < 0.001) and had a significantly higher cost of hospitalization ($240,327 vs. $205,719, p = 0.03), with no significant difference in rate of cerebral infarction, length of intensive care unit stay, length of hospital stay, discharge location, or discharge modified Rankin Score. CONCLUSIONS: This cohort comparison analysis draws into question the practice of protocolized cerebral angiography in patients with aSAH.

Transportation Management Affecting Outcomes of Patients With Spontaneous Intracranial Hemorrhage.

OBJECTIVE: Patients with spontaneous intracranial hemorrhage (sICH) have poor outcomes, in part because of blood pressure variability (BPV). Patients with sICH causing elevated intracranial pressure (ICP) are frequently transferred to tertiary centers for neurosurgical interventions. We hypothesized that BPV and care intensity during transport would correlate with outcomes in patients with sICH and elevated ICP. METHODS: We analyzed charts from adult sICH patients who were transferred from emergency departments to a quaternary academic center from January 1, 2011, to September 30, 2015, and received external ventricular drainage. Outcomes were in-hospital mortality and the Glasgow Coma Scale on day 5 (HD5GCS). Multivariable and ordinal logistic regressions were used for associations between clinical factors and outcomes. RESULTS: We analyzed 154 patients, 103 (67%) had subarachnoid hemorrhage and 51 (33%) intraparenchymal hemorrhage; 38 (25%) died. BPV components were similar between survivors and nonsurvivors and not associated with mortality. Each additional intervention during transport was associated with a 5-fold increase in likelihood to achieve a higher HD5GCS (odds ratio = 5.4; 95% confidence interval, 1.7-16; P = .004). CONCLUSION: BPV during transport was not associated with mortality. However, high standard deviation in systolic blood pressure during transport was associated with lower HD5GCS in patients with intraparenchymal hemorrhage. Further studies are needed to confirm our observations.

Quantitative Chemical Imaging of Nonplanar Microfluidics.

Confocal and multiphoton optical imaging techniques have been powerful tools for evaluating the performance of and monitoring experiments within microfluidic devices, but this application suffers from two pitfalls. The first is that obtaining the necessary imaging contrast often requires the introduction of an optical label which can potentially change the behavior of the system. The emerging analytical technique stimulated Raman scattering (SRS) microscopy promises a solution, as it can rapidly measure 3D concentration maps based on vibrational spectra, label-free; however, when using any optical imaging technique, including SRS, there is an additional problem of optical aberration due to refractive index mismatch between the fluid and the device walls. New approaches such as 3D printing are extending the range of materials from which microfluidic devices can be fabricated; thus, the problem of aberration can be obviated simply by selecting a chip material that matches the refractive index of the desired fluid. To demonstrate complete chemical imaging of a geometrically complex device, we first use sacrificial molding of a freeform 3D printed template to create a round-channel, 3D helical micromixer in a low-refractive-index polymer. We then use SRS to image the mixing of aqueous glucose and salt solutions throughout the entire helix volume. This fabrication approach enables truly nonperturbative 3D chemical imaging with low aberration, and the concentration profiles measured within the device agree closely with numerical simulations.

Selective Loss of Presynaptic Potassium Channel Clusters at the Cerebellar Basket Cell Terminal Pinceau in Adam11 Mutants Reveals Their Role in Ephaptic Control of Purkinje Cell Firing.

A specialized axonal ending, the basket cell "pinceau," encapsulates the Purkinje cell axon initial segment (AIS), exerting final inhibitory control over the integrated outflow of the cerebellar cortex. This nonconventional axo-axonic contact extends beyond the perisomatic chemical GABAergic synaptic boutons to the distal AIS, lacks both sodium channels and local exocytotic machinery, and yet contains a dense cluster of voltage-gated potassium channels whose functional contribution is unknown. Here, we show that ADAM11, a transmembrane noncatalytic disintegrin, is the first reported Kv1-interacting protein essential for localizing Kv1.1 and Kv1.2 subunit complexes to the distal terminal. Selective absence of these channels at the pinceau due to mutation of ADAM11 spares spontaneous GABA release from basket cells at the perisomatic synapse yet eliminates ultrarapid ephaptic inhibitory synchronization of Purkinje cell firing. Our findings identify a critical role for presynaptic K(+) channels at the pinceau in ephaptic control over the speed and stability of spike rate coding at the Purkinje cell AIS in mice. SIGNIFICANCE STATEMENT: This study identifies ADAM11 as the first essential molecule for the proper localization of potassium ion channels at presynaptic nerve terminals, where they modulate excitability and the release of neural transmitters. Genetic truncation of the transmembrane disintegrin and metalloproteinase protein ADAM11 resulted in the absence of Kv1 channels that are normally densely clustered at the terminals of basket cell axons in the cerebellar cortex. These specialized terminals are responsible for the release of the neurotransmitter GABA onto Purkinje cells and also display electrical signaling. In the ADAM11 mutant, GABAergic release was not altered, but the ultrarapid electrical signal was absent, demonstrating that the dense presynaptic cluster of Kv1 ion channels at these terminals mediate electrical transmission. Therefore, ADAM11 plays a critical role at this central synapse.

Primary balloon angioplasty of venous Sinus stenosis in idiopathic intracranial hypertension.

BACKGROUND: Venous sinus stenosis (VSS) stenting has emerged as an effective treatment for patients with Idiopathic Intracranial Hypertension (IIH). However, stenting carries risk of in-stent stenosis/thrombosis and cumulative bleeding risk from long-term dual antiplatelet (DAPT) use. Thus, we investigated the potential safety and efficacy of primary balloon angioplasty as an alternative to stenting in IIH. METHODS: A prospectively maintained single-center registry of IIH patients undergoing endovascular procedures was queried. Inclusion criteria included patients with confirmed IIH and angiographically demonstrable VSS who underwent interventions from 2012- 2021. Patients were dichotomized into primary balloon angioplasty (Group A) and primary stenting (Group S), comparing clinical outcomes using bivariate analyses. RESULTS: 62 patients were included with median age of 33 [IQR 26-37], 74% females. Group A (9/62) and Group S (53/62) had similar baseline characteristics. Papilledema improvement was higher in Group S at 6 weeks and 6 months (44 vs. 93, p = 0.002 and 44 vs. 92%, p = 0.004), with similar improvements across all symptoms. Group S had higher mean post-procedure venous pressure gradient change (8 vs. 3 mmHg, p = 0.02) and a lower CSF opening pressure at 6 months (23 vs. 36 cmH2O, p < 0.001). VPS rescue rate was higher in Group A (44 vs. 2%, p = 0.001). There was only one procedural complications; a subdural hematoma in Group A. CONCLUSIONS: Primary VSS balloon angioplasty provides a marginal and short-lived improvement of IIH symptoms compared to stenting. These findings suggest a cautious and limited role for short-term rescue angioplasty in poor shunting and stenting candidates with refractory IIH.

Tenecteplase versus alteplase before mechanical thrombectomy: experience from a US healthcare system undergoing a system-wide transition of primary thrombolytic.

BACKGROUND: Tenecteplase (TNK) is a genetically modified variant of alteplase (TPA) and has been established as a non-inferior alternative to TPA in acute ischemic stroke (AIS). Whether TNK exerts distinct benefits in large vessel occlusion (LVO) AIS is still being investigated. OBJECTIVE: To describe our first-year experience after a healthcare system-wide transition from TPA to TNK as the primary thrombolytic. METHODS: Patients with AIS who received intravenous thrombolytics between January 2020 and August 2022 were retrospectively reviewed. All patients with LVO considered for mechanical thrombectomy (MT) were included in this analysis. Spontaneous recanalization (SR) after TNK/TPA was a composite variable of reperfusion >50% of the target vessel territory on cerebral angiography or rapid, significant neurological recovery averting MT. Propensity score matching (PSM) was performed to compare SR rates between TNK and TPA. RESULTS: A total of 148 patients were identified; 51/148 (34.5%) received TNK and 97/148 (65.5%) TPA. The middle cerebral arteries M1 (60.8%) and M2 (29.7%) were the most frequent occlusion sites. Baseline demographics were comparable between TNK and TPA groups. Spontaneous recanalization was significantly more frequently observed in the TNK than in the TPA groups (unmatched: 23.5% vs 10.3%, P=0.032). PSM substantiated the observed SR rates (20% vs 10%). Symptomatic intracranial hemorrhage, 90-day mortality, and functional outcomes were similar. CONCLUSIONS: The preliminary experience from a real-world setting demonstrates the effectiveness and safety of TNK before MT. The higher spontaneous recanalization rates with TNK are striking. Additional studies are required to investigate whether TNK is superior to TPA in LVO AIS.

Middle meningeal artery embolization of septated chronic subdural hematomas.

INTRODUCTION: Middle meningeal artery embolization (MMAE) has emerged as a promising new treatment for patients with chronic subdural hematomas (cSDH). Its efficacy, however, upon the subtype with a high rate of recurrence-septated cSDH-remains undetermined. METHODS: From our prospective registry of patients with cSDH treated with MMAE, we classified patients based on the presence or absence of septations. The primary outcome was the rate of recurrence of cSDH. Secondary outcomes included a reduction in cSDH thickness, midline shift, and rate of reoperation. RESULTS: Among 80 patients with 99 cSDHs, the median age was 68 years (IQR 59-77) with 20% females. Twenty-eight cSDHs (35%) had septations identified on imaging. Surgical evacuation with burr holes was performed in 45% and craniotomy in 18.8%. Baseline characteristics between no-septations (no-SEP) and septations (SEP) groups were similar except for median age (SEP vs no-SEP, 72.5 vs. 65.5, p = 0.016). The recurrence rate was lower in the SEP group (SEP vs. no-SEP, 3 vs. 16.7%, p = 0.017) with higher odds of response from MMAE for septated lesions even when controlling for evacuation strategy and antithrombotic use (OR = 0.06, CI [0.006-0.536], p = 0.012). MMAE resulted in higher mean absolute thickness reduction (SEP vs. no-SEP, -8.2 vs. -4.8 mm, p = 0.016) with a similar midline shift change. The rate of reoperation did not differ (6.2 vs. 3.1%, p = 0.65). CONCLUSION: MMAE appears to be equal to potentially more effective in preventing the recurrence of cSDH in septated lesions. These findings may aid in patient selection.

Middle Meningeal Artery Embolization for Chronic Subdural Hematomas With Concurrent Antithrombotics.

BACKGROUND: Chronic subdural hematoma (CSDH) is an increasingly prevalent disease in the aging population. Patients with CSDH frequently suffer from concurrent vascular disease or develop secondary thrombotic complications requiring antithrombotic treatment. OBJECTIVE: To determine the safety and impact of early reinitiation of antithrombotics after middle meningeal artery embolization for chronic subdural hematoma. METHODS: This is a single-institution, retrospective study of patients who underwent middle meningeal artery (MMA) embolizations for CSDH. Patient with or without antithrombotic initiation within 5 days postembolization were compared. Primary outcome was the rate of recurrence within 60 days. Secondary outcomes included rate of reoperation, reduction in CSDH thickness, and midline shift. RESULTS: Fifty-seven patients met inclusion criteria. The median age was 66 years (IQR 58-76) with 21.1% females. Sixty-six embolizations were performed. The median length to follow-up was 20 days (IQR 14-44). Nineteen patients (33.3%) had rapid reinitiation of antithrombotics (5 antiplatelet, 11 anticoagulation, and 3 both). Baseline characteristics between the no antithrombotic (no-AT) and the AT groups were similar. The recurrence rate was higher in the AT group (no-AT vs AT, 9.3 vs 30.4%, P = .03). Mean absolute reduction in CSDH thickness and midline shift was similar between groups. Rate of reoperation did not differ (4.7 vs 8.7%, P = .61). CONCLUSION: Rapid reinitiation of AT after MMA embolization for CSDH leads to higher rates of recurrence with similar rates of reoperation. Care must be taken when initiating antithrombotics after treatment of CSDH with MMA embolization.

Transcompartmental reversal of single fibre hyperexcitability in juxtaparanodal Kv1.1-deficient vagus nerve axons by activation of nodal KCNQ channels.

Kv1.1 channels cluster at juxtaparanodes of myelinated axons in the vagus nerve, the primary conduit for parasympathetic innervation of the heart. Kcna1-null mice lacking these channels exhibit neurocardiac dysfunction manifested by atropine-sensitive atrioventricular conduction blocks and bradycardia that may culminate in sudden death. To evaluate whether loss of Kv1.1 channels alters electrogenic properties within the nerve, we compared the intrinsic excitability of single myelinated A- and Aδ-axons from excised cervical vagus nerves of young adult Kcna1-null mice and age-matched, wild-type littermate controls. Although action potential shapes and relative refractory periods varied little between genotypes, Kv1.1-deficient large myelinated A-axons showed a fivefold increase in susceptibility to 4-aminopyridine (4-AP)-induced spontaneous ectopic firing. Since the repolarizing currents of juxtaparanodal Kv1 channels and nodal KCNQ potassium channels both act to dampen repetitive activity, we examined whether augmenting nodal KCNQ activation could compensate for Kv1.1 loss and reverse the spontaneous hyperexcitability in Kv1.1-deficient A-axons. Application of the selective KCNQ opener flupirtine raised A-axon firing threshold while profoundly suppressing 4-AP-induced spontaneous firing, demonstrating a functional synergy between the two compartments. We conclude that juxtaparanodal Kv1.1-deficiency causes intrinsic hyperexcitability in large myelinated axons in vagus nerve which could contribute to autonomic dysfunction in Kcna1-null mice, and that KCNQ openers reveal a transcompartmental synergy between Kv1 and KCNQ channels in regulating axonal excitability.

Discrete frequency infrared microspectroscopy and imaging with a tunable quantum cascade laser.

Fourier-transform infrared (FT-IR) imaging is a well-established modality but requires the acquisition of a spectrum over a large bandwidth, even in cases where only a few spectral features may be of interest. Discrete frequency infrared (DF-IR) methods are now emerging in which a small number of measurements may provide all the analytical information needed. The DF-IR approach is enabled by the development of new sources integrating frequency selection, in particular of tunable, narrow-bandwidth sources with enough power at each wavelength to successfully make absorption measurements. Here, we describe a DF-IR imaging microscope that uses an external cavity quantum cascade laser (QCL) as a source. We present two configurations, one with an uncooled bolometer as a detector and another with a liquid nitrogen cooled mercury cadmium telluride (MCT) detector and compare their performance to a commercial FT-IR imaging instrument. We examine the consequences of the coherent properties of the beam with respect to imaging and compare these observations to simulations. Additionally, we demonstrate that the use of a tunable laser source represents a distinct advantage over broadband sources when using a small aperture (narrower than the wavelength of light) to perform high-quality point mapping. The two advances highlight the potential application areas for these emerging sources in IR microscopy and imaging.

The chicken wing training model in cerebrovascular microsurgery for the side-to-side bypass.

In the expanding era of endovascular treatment and minimally invasive techniques, the neurosurgical trainees have a steady decrease in the exposure to microsurgical skills. However, there remain a need for neurosurgical trainees to be proficient at such skills, particularly for performing high-stakes interventions such as vascular bypasses. The scarcity of cerebrovascular bypasses coupled with the technical expertise it demands necessitates the presence of a training model for neurosurgical residents and fellows. Regarding the model utilizing the chicken wing for vascular anastomoses, the neurosurgical literature has described many models of bypasses involving the end-to-end and end-to-side anastomoses. The side-to-side anastomosis however is not clearly depicted in these papers. Here we focus on technique, chicken wing anatomy, and donor/recipient vessel diameters to provide a comprehensive guide for trainees. We describe a reproducible and reliable chicken wing model to perform an in-situ side-to-side bypass that incorporates integral elements of a successful bypass surgery.

Blunt Traumatic Vertebral Artery Injuries: Incidence, Therapeutic Management, and Outcomes.

BACKGROUND: Blunt cerebrovascular injury (BCVI) is a term for injuries to the carotid and vertebral arteries (blunt vertebral artery injury [BVAI]) caused by blunt trauma. Computed tomographic angiography is currently the best screening test for BCVI. The subsequent management of any identified vessel injury, however, is not clearly defined. OBJECTIVE: To describe one of the largest cohorts of isolated vertebral artery injuries and report the evolution of treated and untreated lesions and clinical outcomes of treatment regimens used to reduce the risk of injury-related stroke. METHODS: The list included patients who presented to or were transferred to a level 1 trauma center and found to have an isolated BVAI. Patients were included if imaging was performed within 24 hours of presentation. Data collected included location and grade of injury, timing and type of initial therapy, follow-up imaging, evolution of the disease, and associated strokes. RESULTS: A total of 156 patients were included in the analysis. Most patients (135/156) were treated with aspirin alone, 3 with anticoagulation therapy, and 18 did not receive treatment. Three strokes were detected within 24 hours of admission and before treatment initiation. No strokes were detected during the length of the hospitalization for any other patient. CONCLUSION: Our data demonstrate that the risk of stroke after cervical vertebral artery injury is low, and aspirin as a prophylactic is efficacious in grade I and IV injuries. There are limited data regarding grade II and grade III injuries. The benefit of early interval imaging follow-up is unclear and warrants investigation.

Venous Sinus Stenting for Low Pressure Gradient Stenoses in Idiopathic Intracranial Hypertension.

BACKGROUND: Medically refractory idiopathic intracranial hypertension (IIH) is frequently treated with venous sinus stenosis stenting with high success rates. Patient selection has been driven almost exclusively by identification of supraphysiological venous pressure gradients across stenotic regions based on theoretical assessment of likelihood of response. OBJECTIVE: To explore the possibility of benefit in low venous pressure gradient patients. METHODS: Using a single-center, prospectively maintained registry of patients with IIH undergoing venous stenting, we defined treatment groups by gradient pressures of ≤4, 5 to 8, and >8 mmHg based on the most frequently previously published thresholds for stenting. Baseline demographics, clinical, and neuro-ophthalmological outcomes (including optical coherence tomography and Humphrey visual fields) were compared. RESULTS: Among 53 patients, the mean age was 32 years and 70% female with a mean body mass index was 36 kg/m 2 . Baseline characteristics were similar between groups. The mean change in lumbar puncture opening pressure at 6 months poststenting was similar between the 3 groups (≤4, 5-8, and >8 mmHg; 13.4, 12.9, and 12.4 cmH 2 O, P = .47). Papilledema improvement was observed across groups at 6 months (100, 93, and 86, P = .7) as were all clinical symptoms. The mean changes in optical coherence tomography retinal nerve fiber layer (-30, -54, and -104, P = .5) and mean deviation in Humphrey visual fields (60, 64, and 67, P = .5) at 6 weeks were not significantly different. CONCLUSION: Patients with IH with low venous pressure gradient venous sinus stenosis seem to benefit equally from venous stenting compared with their higher gradient counterparts. Re-evaluation of our restrictive criteria for this potentially vision sparing intervention is warranted. Future prospective confirmatory studies are needed.

Biomedical tissue phantoms with controlled geometric and optical properties for Raman spectroscopy and tomography.

To support the translation of Raman spectroscopy into clinical applications, synthetic models are needed to accurately test, optimize and validate prototype fiber optic instrumentation. Synthetic models (also called tissue phantoms) are widely used for developing and testing optical instrumentation for diffuse reflectance, fluorescence, and Raman spectroscopies. While existing tissue phantoms accurately model tissue optical scattering and absorption, they do not typically model the anatomic shapes and chemical composition of tissue. Because Raman spectroscopy is sensitive to molecular composition, Raman tissue phantoms should also approximate the bulk tissue composition. We describe the fabrication and characterization of tissue phantoms for Raman tomography and spectroscopy. These phantoms have controlled chemical and optical properties, and also multilayer morphologies which approximate the appropriate anatomic shapes. Tissue phantoms were fabricated to support on-going Raman studies by simulating the human wrist and rat leg. Surface meshes (triangle patch models) were generated from computed tomography (CT) images of a human arm and rat leg. Rapid prototyping was used to print mold templates with complex geometric patterns. Plastic casting techniques used for movie special effects were adapted to fabricate molds from the rapid prototypes, and finally to cast multilayer gelatin tissue phantoms. The gelatin base was enriched with additives to model the approximate chemistry and optical properties of individual tissue layers. Additional studies were performed to determine optimal casting conditions, phantom stability, layer delamination and chemical diffusion between layers. Recovery of diffuse reflectance and Raman spectra in tissue phantoms varied with probe placement. These phantoms enable optimization of probe placement for human or rat studies. These multilayer tissue phantoms with complex geometries are shown to be stable, with minimal layer delamination and chemical diffusion.

Transfer of Patients with Spontaneous Intracranial Hemorrhage who Need External Ventricular Drain: Does Admission Location Matter?

INTRODUCTION: Patients with spontaneous intracranial hemorrhage (sICH) are associated with high mortality and require early neurosurgical interventions. At our academic referral center, the neurocritical care unit (NCCU) receives patients directly from referring facilities. However, when no NCCU bed is immediately available, patients are initially admitted to the critical care resuscitation unit (CCRU). We hypothesized that the CCRU expedites transfer of sICH patients and facilitates timely external ventricular drain (EVD) placement comparable to the NCCU. METHODS: This is a pre-post study of adult patients transferred with sICH and EVD placement. Patients admitted between January 2011-July 2013 (2011 Control) were compared with patients admitted either to the CCRU or the NCCU (2013 Control) between August 2013-September 2015. The primary outcome was time interval from arrival at any intensive care units (ICU) to time of EVD placement (ARR-EVD). Secondary outcomes included time interval from emergency department transfer request to arrival, and in-hospital mortality. We assessed clinical association by multivariable logistic regressions. RESULTS: We analyzed 259 sICH patients who received EVDs: 123 (48%) CCRU; 81 (31%) 2011 Control; and 55 (21%) in the 2013 Control. The groups had similar characteristics, age, disease severity, and mortality. Median ARR-EVD time was 170 minutes [106-311] for CCRU patients; 241 minutes [152-490] (p < 0.01) for 2011 Control; and 210 minutes [139-574], p = 0.28) for 2013 Control. Median transfer request-arrival time for CCRU patients was significantly less than both control groups. Multivariable logistic regression showed each minute delay in ARR-EVD was associated with 0.03% increased likelihood of death (odds ratio 1.0003, 95% confidence interval, 1.0001-1.006, p = 0.043). CONCLUSION: Patients admitted to the CCRU had shorter transfer times when compared to patients admitted directly to other ICUs. Compared to the specialty NCCU, the CCRU had similar time interval from arrival to EVD placement. A resuscitation unit like the CCRU can complement the specialty unit NCCU in caring for patients with sICH who require EVDs.

Low-Dose Intravenous Heparin Infusion After Aneurysmal Subarachnoid Hemorrhage is Associated With Decreased Risk of Delayed Neurological Deficit and Cerebral Infarction.

BACKGROUND: Patients who survive aneurysmal subarachnoid hemorrhage (aSAH) are at risk for delayed neurological deficits (DND) and cerebral infarction. In this exploratory cohort comparison analysis, we compared in-hospital outcomes of aSAH patients administered a low-dose intravenous heparin (LDIVH) infusion (12 U/kg/h) vs those administered standard subcutaneous heparin (SQH) prophylaxis for deep vein thrombosis (DVT; 5000 U, 3 × daily). OBJECTIVE: To assess the safety and efficacy of LDIVH in aSAH patients. METHODS: We retrospectively analyzed 556 consecutive cases of aSAH patients whose aneurysm was secured by clipping or coiling at a single institution over a 10-yr period, including 233 administered the LDIVH protocol and 323 administered the SQH protocol. Radiological and outcome data were compared between the 2 cohorts using multivariable logistic regression and propensity score-based inverse probability of treatment weighting (IPTW). RESULTS: The unadjusted rate of cerebral infarction in the LDIVH cohort was half that in SQH cohort (9 vs 18%; P = .004). Multivariable logistic regression showed that patients in the LDIVH cohort were significantly less likely than those in the SQH cohort to have DND (odds ratio (OR) 0.53 [95% CI: 0.33, 0.85]) or cerebral infarction (OR 0.40 [95% CI: 0.23, 0.71]). Analysis following IPTW showed similar results. Rates of hemorrhagic complications, heparin-induced thrombocytopenia and DVT were not different between cohorts. CONCLUSION: This cohort comparison analysis suggests that LDIVH infusion may favorably influence the outcome of patients after aSAH. Prospective studies are required to further assess the benefit of LDIVH infusion in patients with aSAH.

Thrombectomy for acute ischemic stroke with the new Sofia 6-French PLUS distal access reperfusion catheter: A single-center experience.

INTRODUCTION: The Sofia 6-French PLUS catheter is a recently approved aspiration catheter for use in neuro-endovascular procedures. The description of Sofia 6-French PLUS use in acute ischemic stroke is limited. OBJECTIVE: The purpose of this article is to describe our initial experience with the new Sofia 6-French PLUS catheter for treatment of acute ischemic stroke and to report on its safety and efficacy. METHODS: We performed a retrospective study of 54 thrombectomy cases treated with the Sofia 6-French PLUS catheter. Mean patient age and admission National Institutes of Health Stroke Scale score were 65.30 (1.92) and 15.98 (0.89), respectively. The most common sites of vessel occlusion included the M1 segment (50%) and internal carotid artery (31%). Thrombectomy was performed using the direct aspiration first pass technique and/or aspiration in conjunction with a stent retriever. RESULTS: Successful navigation of the Sofia 6-French PLUS catheter to the site of thromboembolus was achieved in 94% of cases. Revascularization was achieved in a total of 47 cases (87%). Mean time from groin access to revascularization was 42.79 (3.23) min. There were no catheter-related complications. Final outcome data was available for 44 patients (81%). Of these patients, 41% achieved a good outcome (modified Rankin scale score of 0-2) at 60-90 day follow-up, 41% had a poor outcome (modified Rankin 3-5) and eight patients died (18%). CONCLUSIONS: We demonstrate the safe and effective use of the Sofia 6-French PLUS catheter for treatment of acute ischemic stroke. Future studies in the form of a randomized clinical trial or multicenter registry are warranted to further evaluate its comparative safety and efficacy.

Sedation Patterns and Hyperosmolar Therapy in Emergency Departments were Associated with Blood Pressure Variability and Outcomes in Patients with Spontaneous Intracranial Hemorrhage.

BACKGROUND: Spontaneous intracranial hemorrhage (sICH) is associated with high mortality. Little information exists to guide initial resuscitation in the emergency department (ED) setting. However, blood pressure variability (BPV) and mechanical ventilation (MV) are known risk factors for poor outcome in sICH. OBJECTIVES: The objective was to examine the associations between BPV and MV in ED (EDMV) and between two ED interventions - post-MV sedation and hyperosmolar therapy for elevated intracranial pressure - and BPV in the ED and in-hospital mortality. METHODS: We retrospectively studied adults with sICH and external ventricular drainage who were transferred to a quaternary academic medical center from other hospitals between January 2011 and September 2015. We used multivariable linear and logistic regressions to measure associations between clinical factors, BPV, and outcomes. RESULTS: We analyzed ED records from 259 patients. There were 143 (55%) EDMV patients who had more severe clinical factors and significantly higher values of all BPV indices than NoEDMV patients. Two clinical factors and none of the severity scores (i.e., Hunt and Hess, World Federation of Neurological Surgeons Grades, ICH score) correlated with BPV. Hyperosmolarity therapy without fluid resuscitation positively correlated with all BPV indices, whereas propofol infusion plus a narcotic negatively correlated with one of them. Two BPV indices, i.e., successive variation of blood pressure (BPSV) and absolute difference in blood pressure between ED triage and departure (BPDepart - Triage), were significantly associated with increased mortality rate. CONCLUSION: Patients receiving MV had significantly higher BPV, perhaps related to disease severity. Good ED sedation, hyperosmolar therapy, and fluid resuscitation were associated with less BPV and lower likelihood of death.