bluuebunny/crossref_metadata_2025_split huggingface dataset:
415 Correlation of Platelet Reactivity Testing and CYP2C19 Metabolizer Status in Patients Undergoing Endovascular Neurointervention
Authors: Benish Alam , Lucke-Wold Brandon , Laurent Dimitri , Elchynski Amanda , Cicali Emily , Wiisanen Kristin , Cavallari Larissa , Hoh Brian L. 
Published: March 2022

INTRODUCTION:
Dual-antiplatelet therapy (DAPT) is clinically indicated for patients undergoing endovascular procedures. Clopidogrel is the most commonly used P2Y12 inhibitor used for DAPT, and is a prodrug bioactivated by the CYP2C19 enzyme. Inferring platelet response can be done by genotyping CYP2C19 to determine metabolizer status. Patients with two functional alleles are considered normal metabolizers (NM), patients with one or two increased activity alleles are rapid (RM) or ultra-rapid metabolizers (UM), respectively, and patients with one or two loss-of-function (LOF) alleles are intermediate (IM) or poor metabolizers (PM), respectively. Another method of measuring antiplatelet response to clopidogrel is the VerifyNow Platelet assay (measured in platelet reactivity units [PRUs]), but the optimal range of PRUs in neuro-endovascular procedures has not yet been established. At UF Health, platelet reactivity testing is routine, but CYP2C19 genotyping is less frequent in patients undergoing these procedures.

METHODS:
Data were collected from the EMR patients who had a CYP2C19 genotype result ordered by the neurosurgical department. We assessed platelet reactivity tests and antiplatelet medication changes between different phenotype groups. Phenotypes included ultra-rapid, rapid, normal, intermediate and poor metabolizers. Patients were categorized as non-responders to clopidogrel if their platelet reactivity tests were >204 PRUs prior to medication change, hyper-responders if their platelet reactivity tests were <20 PRUs, and optimal responders if reactivity fell between 20-204 PRUs.

RESULTS:
41 neurosurgical patients were genotyped. CYP2C19 phenotypes included ultra-rapid metabolizers (10%), rapid metabolizers (34%), normal metabolizers (37%), intermediate metabolizers (12%) and poor metabolizers (7%). Six patients had dose decreased to 75 mg QOD; 83% were hyper-responders. Three patients had their dose halved; 100% were hyper-responders. Four patients were switched to ticagrelor; 100% were clopidogrel non-responders.

CONCLUSION:
Patients who had their clopidogrel dose reduced were generally classified as hyper-responders based on platelet reactivity testing, and majority had increased CYP2C19 enzyme activity based on genotype. Of the non-responders who had a medication change to alternative P2Y12 therapy,majority had decreased CYP2C19 enzyme activity.
417 Predicting Hematoma Expansion after Spontaneous Intracerebral Hemorrhage Through a Noncontrast Computed Tomography Based Model
Authors: Seymour Samantha , Rava Ryan , Ionita Ciprian , Snyder Kenneth V. , Waqas Muhammad , Davies Jason , Levy Elad I. , Siddiqui Adnan H. 
Published: March 2022

INTRODUCTION:
Spontaneous Intracerebral Hemorrhage (ICH) accounts for 15% of all acute strokes and is the deadliest stroke subtype with a 40% mortality rate after one month. More than 75% of all ICH patients are severely disabled or deceased after the first year. 30% of patients continue to bleed and demonstrate significant hematoma expansion (HE). Once HE occurs in ICH patients, treatment options are limited and the patient prognosis is significantly decreased.

METHODS:
NCCT scans for 200 ICH patients (70 expansion, 130 non-expansion) who presented with stroke-like symptoms between August 2016 and December 2019 were collected for this study. The patients had at least one of the following hemorrhages: intraparenchymal (n = 181), intraventricular (n = 45), subdural (n = 13), or subarachnoid (n = 19). Data augmentation and skull-stripping was conducted. A deep neural network was used to identify and segment the hemorrhagic region. Two networks were trained using two-dimensional images created by taking the standard deviation and mean of the voxel intensities over the entire volume to classify hematoma expansion using a training:testing split of 80:20 and 20 iterations of Monte Carlo cross validation.

RESULTS:
Hematoma expansion metrics using st.dev images are seen with a 95% confidence interval as: accuracy = 0.65 ± 0.04, sensitivity = 0.79 ± 0.06, specificity = 0.58 ± 0.06, precision = 0.51 ± 0.04, negative predictive value (NPV) = 0.84 ± 0.03. Metrics using mean images are: accuracy = 0.64 ± 0.03, sensitivity = 0.68 ± 0.08, specificity = 0.63 ± 0.07, precision = 0.49 ± 0.02, NPV = 0.78 ± 0.03.

CONCLUSION:
CNNs have the ability to predict hematoma expansion by utilizing two-dimensional images created from flattening NCCT volumes. Taking the st.dev over the NCCT volume within the hemorrhagic region is a better predictor of HE due to its more cautious approach indicated by a higher sensitivity metric.
418 First-line Stent Retriever Thrombectomy vs Direct Aspiration for Acute Basilar Artery Occlusion: A Systematic Review and Meta-analysis
Authors: Texakalidis Pavlos , Xenos Dimitrios , Karras Constantine L. , Murthy Nikhil , Hopkins Benjamin , Kontzialis Marinos , Rivet Dennis J. , Reavey-Cantwell John 
Published: March 2022

INTRODUCTION:
Mechanical thrombectomy (MT) for acute anterior circulation stroke is an already established therapy. Recently, MT has been also increasingly utilized for basilar artery occlusion (BAO); the mainstay of MT modalities are stent retriever (SR) and direct aspiration (DA). Several studies have been recently published comparing the two approaches.

METHODS:
A systematic review and meta-analysis was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines.

RESULTS:
Overall, eight studies comprising 693 patients with acute BAO were included (SR: 457; DA: 236). The SR group was associated with statistically significant lower odds for successful recanalization defined as modified Thrombolysis in Cerebral Infarction (mTICI) 2b/3 (SR:81.9%, DA: 88.2%; OR:0.54; 95%CI:0.31-0.94; I2:0%) and mTICI 3 (SR: 51%, DA: 62.5%; OR:0.47; 95%CI:0.23-0.95; I2:62.1%) compared to DA. Favorable outcome rates defined as modified Rankin Scale (mRS) = 2, were similar between the two groups (SR: 37.8%, DA: 41.9%; OR:0.83; 95%CI: 0.60-1.16; I2:0%). The rates of symptomatic ICH (sICH) were higher in the SR group compared to the DA group (SR: 8.7% vs DA: 0.9%, however statistical significance was not reached OR: 3.57; 95%CI: 0.75-16.95; I2:0%). Similarly, subarachnoid hemorrhage (SAH) (SR: 5%, DA:0%; OR:4.71; 95%CI: 0.82-26.90; I2:0%) and vessel perforation (SR: 3.4%, DA: 1.1%; OR: 2.64; 95%CI: 0.43-16.33; I2:0%) rates were higher in the SR group but again significance was not reached. The rates of 90-day mortality were similar between the two groups (SR: 27.5%, DA: 28.1%; OR: 1.07; 95%CI: 0.67-1.70; I2:0%). Procedure duration was significantly shorter when DA was used compared to SR (WMD: 26.10;95%CI:13.28-38.92; I2:35.3%).

CONCLUSION:
DA is associated with statistically significant higher odds of successful mTICI 2b/3 and mTICI 3 recanalization rates and shorter procedure duration compared to SR. In addition, in absolute numbers, SR was associated with higher rates of sICH, SAH and vessel perforation, however, statistical significance was not reached most likely due to the relatively low sample size.
419 Long Sheath Use in Stroke Thrombectomy Leads to Improved Outcomes in Octogenerians
Authors: Nowicki Kamil W. , Dolia Jay , Shah Kavit , Alattar Ali A. , Tonetti Daniel , Jadhav Ashutosh , Lang Michael J. , Gross Bradley A. 
Published: March 2022

INTRODUCTION:
Comparative evaluation of efficacy of using a long sheath-first approach in stroke thrombectomy patients where no initial arch information is available does not exist. Lower door-to-reperfusion times are associated with better outcomes in stroke thrombectomy. Multiple factors affect reperfusion times including approach, arch navigability, and the amount of support provided by equipment.

METHODS:
Study Design and Setting: An institutional review-board-approved, prospectively maintained endovascular arterial thrombectomy database from 2016 to 2018 was reviewed. Inclusion criteria: manual aspiration thrombectomy or stent-assisted, femoral approach, >80 yo, and LVO in anterior circulation. Study Variables: Demographic information such as age, sex, medical comorbidities, NIHSS score on presentation, tPA administration, and thrombus location were extracted. Arch navigability was defined by time from puncture to first base catheter run. Procedural times, and angiographic results (TICI score) were recorded and used as metrics for efficacy. Ninety-day outcome was also evaluated based on modified Rankin scale. The analysis was performed based on an intention-to-treat analysis. Statistical Analysis: Univariate statistical analysis was performed using an unpaired t test with Bonferonni correction for continuous variables and Fisher’s exact test for categorical variables. Statistically significant differences between groups were defined as p < 0.05. Procedural Technique: All procedures were performed emergently under local anesthesia. Consent was obtained from the patient or their next of kin under our institution’s guidelines.

RESULTS:
A total of n = 287 patients were included in the final analysis. There were no significant differences in baseline demographics. Upfront “long-sheath first” approach resulted in improved outcomes: time to first run (15.6 vs 32 min, p = 0.0005), time to first pass (21.4 vs 40 min, p < 0.0001), time to final reperfusion (35.8 vs 50 min, p < 0.0001), delta NIHSS (2.2 vs 6.6, p < 0.0001).

CONCLUSION:
Upfront “long-sheath first” approach results in improved outcomes during stroke thrombectomy in octogenerian population.
420 Task Related Physiology of the Dentalothalamocortical Circuit in Naïve and Stroke Rats
Authors: Momin Arbaz , Hermann John , Baker K. , Machado André 
Published: March 2022

INTRODUCTION:
As stroke mortality has declined, a growing number of patients are left with chronic, residual post-stroke hemiparesis. Targeted, neurostimulation-based upregulation of activity of the dentatothalamocortical (DTC) pathway, a disynaptic pathway with net excitatory effects on widespread areas of the cerebral cortex, has been proposed previously as a potential approach to enhance cortical excitability in surviving, perilesional cortical regions and promote motor rehabilitation after a stroke.

METHODS:
13 rats (7 naÏve and 6 stroke) were implanted unilaterally with a 9 channel recording electrode in the DN (ipsilateral to dominate forepaw) and cortical EEG screws (contralateral to dominate forepaw) were placed over the perilesional area. LFPs were recorded from the DN and motor cortex during a reach/pull task for 4 weeks after surgery.

RESULTS:
At a 25g force threshold, DN LFPs were diminished in the 8-12 hz in the pre-movement and movement phase in stroke rats compared with naÏve rats. At a 5g force threshold, 8-12 hz LFPs in the DN were significantly diminished in the stroke animals relative to naive during the pre-movement and movement phase (p < .05). At a 50g force threshold, cortical 1.5-4 hz oscillations were significantly diminished during the pre-movement and movement phase in stroke rats compared to naÏve rats (p < .05).

CONCLUSION:
Diminished 8-12 hz reach-related LFP activity in the DN of stroke rats relative to naÏve rats during the pre-movement and movement phase of a reaching task, may function as a potential predefined trigger for the onset of deep brain stimulation as a therapeutic intervention to promote motor rehabilitation for chronic post-stroke hemiparesis.
421 Coherence Between the Subthalamic Nucleus and the Primary Motor Cortex in Patients With Parkinson's Disease
Authors: Souza de Castro Joao P. 
Published: March 2022

INTRODUCTION:
DBS is established as a safe and effective treatment for Parkinson’s Disease (PD). The development of second generation stimulators based on closed loop systems is dependent upon deeper understanding of the cortical control of motricity and its coupling with STN oscillations.

METHODS:
Experimental study on human subjects involving 10 patients with idiopathic PD with indication for deep brain stimulation implants into the STN. Primary motor area of the hands were identified preoperatively with fMRI. Corkscrew electrodes were implanted in the scalp to obtain C3-Cz and C4-Cz derivations of the EEG. Needle electrodes were implanted into the thenar and hypothenar muscles of both hands to record motor evoked potentials and voluntary myoelectric activity. At the time of implantation of the definitive macro-electrodes, the best contacts were connected to the electrophysiological monitoring device to record STN local field potentials (LFP) from 1 side at a time. During the next 3 minutes, the patient was asked to perform closing and opening movements of the hand contralateral to the implant. Simultaneously recordings of hand-EMG, EEG signals from M1, and STN field potentials were acquired for off line analysis.

RESULTS:
Our data indicate that during epochs of hand movements, theta and beta range components of the EEG related to M1 were significantly increased as compared with rest epochs. Additionally, we demonstrated that, during movement, the cross correlation between STN-LFP and M1 significantly increased (p < 0.001).

CONCLUSION:
Movement control is highly dependent upon theta and beta EEG components and upon a high coherence between STN and M1 specifically occurring during movement. The development of closed-loop stimulation devices should consider this physiology to reach better results.
422 Safety and Efficacy of Responsive Neurostimulation for the Treatment of Medically Refractory Epilepsy: A 5-Year Follow-Up Study
Authors: Roa Jorge A. , Feng Rui , Schupper Alexander J. , Fields Madeline , Marcuse Lara , Germano Isabelle M. , Bederson Joshua B. , Ghatan Saadi , Panov Fedor 
Published: March 2022

INTRODUCTION:
Despite antiepileptic drugs (AEDs), >30% of patients with epilepsy continue to have seizures. Responsive Neurostimulation (RNS) provides a nondestructive treatment option for patients with drug-resistant epilepsy (DRE). To date, the safety and efficacy of RNS have not been fully studied due to the lack of prospective data.

METHODS:
We performed a retrospective analysis of prospectively collected data of DRE patients who underwent RNS implantation between September 2015-December 2020 at our Institution. Patients were followed postoperatively to evaluate seizure-freedom and complications. For each patient, response to RNS was determined as an overall percentage based on the relative reduction in seizure duration/severity, medication requirements and post-ictal state.

RESULTS:
A total of 103 patients underwent RNS placement. Seven patients developed infections: three required partial salvaging of the system, and only two (1.9%) required complete removal of the RNS device. Six (5.8%) patients experienced small asymptomatic post-operative hemorrhages; none required re-intervention. No cases of stroke or device malfunction/migration were seen. The average follow-up period was 20±13.6 months. Of 74 patients with = 6-month follow-up available, 15 (20.3%) became seizure-free, 18 (24.3%) achieved 75-99% control of seizures, 19 (25.7%) achieved 50-74%, 15 (20.3%) achieved 25-49% and 7 (9.5%) achieved <25% success. Patients with seizures originated in the mesial temporal lobe had a tendency to achieve =75% seizure control (OR = 1.4, P = 0.056). Variables associated with worse outcome (<25% seizure control) included: younger age at epilepsy onset (OR = 2.4, P = 0.043), syndromic etiology (OR = 3.6, P = 0.041), prior no response to =5 AEDs (OR 4.3, P = 0.026) and prior surgical intervention (OR = 1.8, P = 0.052).

CONCLUSION:
RNS achieved = 50% seizure control in ∼70% of patients. Infections and tract-hemorrhages are the most common complications, but rarely require re-intervention. Seizure-freedom after RNS implantation may be significantly lower in patients affected by aggressive epileptogenic syndromes since a young age, and those who have failed to respond to >5 drugs and prior surgical interventions.
424 The Role of the Mid Fusiform Gyrus in Lexical Retrieval
Authors: Snyder Kathryn , Donos Cristian , Forseth Kiefer , Rollo Patrick , Breier Joshua , Fischer-Baum Simon , Tandon Nitin 
Published: March 2022

INTRODUCTION:
Temporal lobe resections for epilepsy or neoplasms often result in significant confrontation naming decline. This can be socio-economically disabling and prevent patients from returning to independent functioning. While the exact substrates responsible are unknown, it was previously assumed that injury to the superior temporal gyrus or resection size predicts these declines. A clear understanding of the most critical constituents might influence surgical strategies to minimize language declines.

METHODS:
Data were obtained from 95 patients who underwent surgical resection in the dominant left temporal lobe for medication-resistant epilepsy. Patients underwent neuropsychological testing and MRI prior to and 6 months following surgery. Lesion masks were traced on postoperative MRIs and aligned to a normative space. The effects of preoperative scores and seizure outcomes were removed from postoperative scores via linear regression. VLSM using multivariate support vector regression was used to assess postoperative test scores. Beta maps were converted to p values and corrected using a permutation-based cluster level correction. Additionally, a surface-based mixed-effects multilevel analysis was used to estimate broadband gamma activity during picture naming across a subset of subjects with ECoG recordings, and results were integrated with VLSM. Lastly, fMRI (picture naming) was used to assess SNR in significant regions.

RESULTS:
VLSM analysis revealed that the loss of basal temporal regions was associated with a prominent decline in BNT scores (p < 0.005). Similarly, ECoG analysis showed a significant increase in activity in the mid fusiform gyrus (mFus) immediately preceding articulation. Many of these voxels were associated with low SNR on fMRI, perhaps explaining why this region has been under-appreciated as the locus responsible for postoperative deficits.

CONCLUSION:
The importance of the ventral temporal cortex in lexical access is shown using multivariate VLSM and supported with ECoG. While it has previously been assumed that mFus lesions do not cause pervasive impairment, our data and recent work (FATES study) argue against this and support the role of the mFus as a critical semantic access hub.
429 Racial Disparities Persist Despite Increased Utilization of Deep Brain Stimulation Surgery for Parkinson’s Disease
Authors: Cramer Samuel , Do Truong , Palzer Elise , Naik Anant , Rice Abigail , Novy Savannah , Hanson Jacob , Piazza Amber , Howard Madeleine , Huling Jared , Chen Clark C. , McGovern Robert A. 
Published: March 2022

INTRODUCTION:
Deep brain stimulation (DBS) provides improved quality of life for properly selected individuals with Parkinson’s disease (PD). Though DBS is a widely accepted and efficacious therapy for PD, significant racial disparities have been reported in the access to DBS, particularly for Black patients.

METHODS:
The National Inpatient Sample (NIS) was queried to identify PD patients who underwent DBS placement between 2002 and 2018. We examined DBS utilization relative to PD admissions, patient characteristics over time, and whether ACA passage was associated with changes in insurance and DBS utilization among different racial/ethnic groups.

RESULTS:
In 2014-2018, the odds of PD patients receiving DBS therapy increased 56% compared to 2002-2005 (p < 0.001). In a multivariate logistic regression analysis, the most important factors affecting the likelihood of DBS surgery were race, insurance status and the presence of comorbidities. Black PD patients were 1/5 as likely as White patients to undergo DBS placement (p < 0.001). Individuals with = 2 comorbidities were 20 times less likely to undergo DBS. Patients insured privately compared to those insured by Medicare/Medicaid were 5.22 times as likely to undergo DBS. Passage of the ACA was associated with 2.62 times higher odds of DBS in 2010-2013 for Black PD patients compared to 2002-2005 (p = 0.008). During the period 2014-2018, Black PD patients were 2.33 times more likely to undergo DBS compared to the period 2002-2005 (p = 0.008).

CONCLUSION:
DBS is increasingly used for healthy, privately insured PD patients. Significant racial disparities persist in the use of DBS for PD despite a modest improvement following passage of the ACA, but prior to most of its implementation, indicating other factors contributed to this change.
430 Trans-cerebellar Stereotactic-guided Cisternoperitoneal Shunt Placement for Idiopathic Intracranial Hypertension
Authors: Cho Steve S. , Wakim Andre , Teng Clare W. , Sarris Christina E. , Smith Kris 
Published: March 2022

INTRODUCTION:
Idiopathic intracranial hypertension (IIH, pseudotumor cerebri) mainly affects young, obese females and can cause debilitating symptoms as well as optic nerve ischemia if not treated. Cerebrospinal fluid (CSF) diversion is often necessary to reduce intracranial pressure (ICP). Ventriculoperitoneal shunts (VPS) and lumboperitoneal shunts (LPS) are the main methods of CSF diversion but both are fraught with high rates of shunt failures in IIH patients. We propose the novel trans-cerebellar stereotactic-guided cisternoperitoneal shunt (TCSG-CPS) technique, which places the proximal shunt catheter in the posterior cisterna magnum, which is a non-collapsible CSF space.

METHODS:
Retrospective data regarding perioperative and postoperative data from all patients who underwent TCSG-CPS placement from 2015-2020 for IIH were collected. Intraoperatively, patients are positioned as for VPS but with the head turned further laterally to adequately expose the retrosigmoid space. Using neuronavigation, the transverse and sigmoid sinuses are located and an opening is made at the transverse-sigmoid junction. The proximal catheter is then inserted transcerebellarly into the posterior foramen magnum using electromagnetic neuronavigation to accurately track the catheter tip.

RESULTS:
Thirty-two patients underwent TCSG-CPS placement. 91% were female, with a mean BMI of 36.0 ± 7.5. Fourteen patients had undergone prior VPS or LPS placement with shunt failures. Shunt placement, including removal of prior shunts when applicable, took an average of 150 minutes. There were no intraoperative complications and patients were discharged uneventfully after mean 1.7 days. On follow-up visits at 6 months, 81% had relief of their presenting symptoms. Shunt survival without revision at 1 and 3 year were 86% and 67%, respectively. Overall infection rate was 0% in the study period.

CONCLUSION:
The TCSG-CPS offers an alternative solution to VPS and LPS for CSF diversion in patients with IIH and demonstrates a lower failure rate and more durable symptom relief compared to historical data on VPS and LPS. Using the proper techniques and equipment promotes safe and facile placement of the proximal catheter.