bluuebunny/crossref_metadata_2025 huggingface dataset:
447 Modulation of Patient Reported Outcomes and Opioid Consumption Following Open Craniotomy: The Efficacy and Safety of Subcutaneous Sumatriptan
Authors: Woodward Josha , Kelly Ryan Matthew , Patiel Aahaska , Herbst Julia , Meza Samuel , Koro Lacin , Keegan Kevin , Panos Nicholas , Munich Stephan , Munoz Lorenzo , Sani Sepehr
Published: March 2023

INTRODUCTION:

Traditional pain management regimens following open craniotomy commonly employ opioid medications. As a medication class, opioids present a considerable adverse effect profile and the potential for medication abuse. Alternative medication regimens to better address post-craniotomy pain while mitigating opioid-related adverse effects are insufficiently studied. However, as a dural-based 5-HT1D receptor agonist that regulates vasoconstriction and inflammatory peptide signaling, sumatriptan shows promise to improve pain scores and reduce opioid requirements.

METHODS:

This is a single academic center, retrospective cohort study of 130 consecutive adult patients undergoing open craniotomy between 7/2015 and 8/2021. Patients were divided between a Control and Sumatriptan cohort contingent upon administration of a single 6mg subcutaneous injection of sumatriptan within 1-hour of surgery completion and prior to opioid administration. Opioid consumption at 6, 12 and 24-hours postoperative and admission total, inpatient length of stay (LOS) and 30-day global representation/readmission were evaluated.

RESULTS:

130 patients were equally divided between the Sumatriptan and Control cohorts for analysis. No difference in baseline demographics was noted. A significant reduction of mean pain score at 6, 12 and 24-hours following surgery substantially favored the Sumatriptan cohort (p < 0.05). Further, a nonsignificant reduction in opioid requirements was observed at all timepoints favoring the sumatriptan cohort (p > 0.05). 30-day global ED evaluation and readmission rates between cohorts were similar (p > 0.05). Overall LOS in the Sumatriptan and Control cohorts were 5.3 ± 3.6 vs 6.5 ± 5.6 days (p > 0.05). No difference in the rate of incisional or intracerebral hemorrhage was noted between cohorts (p > 0.05).

CONCLUSIONS:

In the present study, patients in the Sumatriptan cohort demonstrated enhanced pain control and reduced opioid requirements suggesting sumatriptan represents a safe and efficacious agent for the modulation of pain following open craniotomy.
453 Neuromodulation of the Centromedian Nucleus of the Thalamus for the Treatment of Generalized Drug-Resistant Epilepsy: Novel Insights Into the Targeting and the Anti-Seizure Mechanism From a Tractographic Study
Authors: Remore Luigi , Omidbeigi Mahmoud , Tsolaki Evangelia , Wei Wenxin , Chodakiewitz Michael , Eliashiv Dawn , Nariai Hiroki , Fallah Aria , Bari Ausaf A.
Published: March 2023

INTRODUCTION:

Neuromodulation of the centromedian nucleus (CM) has been investigated with promising results for the treatment of generalized drug-resistant epilepsy (gDRE). Recent evidence suggests a more clinically beneficial “sweet-spot” corresponding to the thalamic area between the antero-lateral CM and the posterior subdivision of the ventrolateral nucleus. However, it is unclear if this region can be considered a new target or still a subcomponent of CM.

METHODS:

We analyzed diffusion and structural MRI scans from 9 DRE patients, who underwent CM-stimulation surgery. CM masks from the THOMAS atlas and 2 spherical ROIs from the MNI coordinates of the sweet-spot and the cold-spot in Warren et al. 2022 were used as seed regions for probabilistic tractography (FSL software). 42 cortical and subcortical areas were selected as target regions and divided in 5 groups: sensorimotor, associative, basal ganglia, infratentorial and limbic structures. Mean structural connectivity was calculated using descriptive statistics and statistical significance was tested with a standard t-test. Statistical comparison among the 3 seed regions was conducted using ANOVA.

RESULTS:

For each seed, statistically significant (p < 0.05) connections were found for all the 5 groups. When comparing the 3 seeds, the CM and the cold-spot had stronger connections with the postcentral and the superior temporal cortices, the brainstem, the caudate and the amygdala; the sweet-spot with the precentral and the superior frontal cortices, the cerebellum, the putamen and the nucleus accumbens. However, no statistically significant differences resulted among the 3 seeds.

CONCLUSIONS:

CM has widespread connections with both cortical and subcortical structures. The sweet-spot seems to correspond to the parvocellular part of CM on the border with the ventrolateral nucleus. CM connections with frontal and prefrontal areas and the cerebellum may underlie the beneficial effect against generalized seizures.
457 CD39 Expression in the Glioblastoma Microenvironment does not Affect T Cell Exhaustion or Survival
Authors: Zheng Allison , Pappu Ananya , Gill Sabraj , Stelter Isabella , Aghi Manish Kumar
Published: March 2023

INTRODUCTION:

Glioblastoma (GBM), the most common malignant brain tumor, is notable for its dysfunctional T-cells. The initial optimism of Immune checkpoint inhibitors has been tempered as these agents have not been successful in treating GBM. CD39 is the first enzyme in the breakdown of ATP to adenosine and is highly upregulated in GBM. CD39 is also thought to contribute to T-cell exhaustion. However, inhibiting the CD39 ATP breakdown pathway did not improve survival in mice, even with PD-1 inhibition, leading to uncertainty about whether non-enzymatic functions of CD39 give it a role in T-cell exhaustion in GBM.

METHODS:

We performed intracranial injections of SB28 and GL261 GBM cell lines into CD39 global nulls (KO) and C57BL/6J (WT) mice and measured survival. Another cohort of mice were similarly injected and sacrificed after 2 weeks. These tumors were analyzed for T-cell exhaustion markers using flow cytometry.

RESULTS:

There was no survival benefit seen in either cell line when compared to wild type mice. The immune cell profile was not found to be statistically different between KO and WT mice. Next, expression of known exhaustion markers such as PD-1, TIM3, and LAG3 on tumor infiltrating lymphocytes (TILs) were analyzed. Expression of TIM3 and 2B4 were found to be increased in CD39KO TILs compared to WT (p < 0.01). Additionally, numerous exhaustion markers such as LAG3, TIGIT, and CTLA4 were decreased on TILs compared to peripheral blood T-cells in tumor-bearing mice (p < 0.01).

CONCLUSIONS:

These results suggest that CD39 lacks a direct impact on GBM outcomes but may affect the expression of other exhaustion markers. Further studies will continue to investigate the interaction between immune checkpoint molecules in GBM.
458 Assessment of MGMT Methylation Status Using High-Performance Liquid Chromatography in Newly Diagnosed Glioblastoma
Authors: Hanihara Mitsuto , Miyake Kunio , Watanabe Atsushi , Yamada Yuriko , Oishi Naoki , Kawataki Tomoyuki , Inukai Takeshi , Kondo Tetsuo , Kinouchi Hiroyuki
Published: March 2023

INTRODUCTION:

The utility of O6-methylguanine-DNA methyltransferase (MGMT) gene promoter methylation status as a prognostic marker in patients with glioblastoma (GBM) has been established. However, the number of CpG sites that must be methylated to cause transcriptional silencing remains unclear, and no significant consensus exists on the optimal method of assessing MGMT methylation.

METHODS:

W analyzed the MGMT methylation status of 28 isocitrate dehydrogenase–wild-type GBMs treated with temozolomide using ion-exchange HPLC and bisulfite sequencing using frozen samples. We designed three primers for separate regions (regions 1–3) that had 21 to 38 CpGs for PCR and validated the MGMT promoter methylation status.

RESULTS:

There was a strong correlation between HPLC and bisulfite sequencing results (R = 0.794). The optimal cutoff values for MGMT methylation in HPLC were determined to allow differentiation of patient prognosis by receiver operating characteristic curve analysis. The cutoff values were 34.15% for region 1, 8.84% for region 2, and 36.72% for region 3. Kaplan–Meyer curve analysis estimated that the most differentiated prognosis was enabled in the setting of 8.84% methylation of MGMT in region 2. Progression-free survival and overall survival were significantly longer for patients in this setting of region 2 methylation (p = 0.00365 and p = 0.00258, respectively).

CONCLUSIONS:

The combination of our HPLC method and the original primer setting provides a new standard method for determination of MGMT methylation status in patients with GBM and is useful for refining MGMT-based drug selection.
464 Alternative RNA Splicing Changes Underlie Meningioma DNA Methylation Groups
Authors: Leclair Nathan , Choudhury Abrar , Magill Stephen , Shen Erica , Bulsara Ketan R. , Raleigh David R. , Anczukow Olga
Published: March 2023

INTRODUCTION:

Meningiomas are the most common primary intracranial tumor. They are associated with genetic mutations found across broad epigenetic or transcriptomic groups. Alternative RNA splicing (AS) is a critical step in gene expression that involves the differential inclusion of sequences into the mature mRNA. Dysregulation of AS is a hallmark of human tumors, but its contributions to meningioma tumorigenesis are incompletely understood. In particular, whether meningioma DNA-methylation groups are associated with specific downstream changes in AS is unknown.

METHODS:

AS events from 184 meningiomas were characterized using rMATS, a computational tool that quantifies percent splicing event inclusion (PSI) from short-read RNA-sequencing. Differential gene expression was quantified using DESeq2.

RESULTS:

Our analysis revealed 135 differentially spliced events in Immune-enriched vs. Hypermitotic meningiomas, 126 events in Immune-enriched vs. Merlin-intact meningiomas, and 185 events in Merlin-intact vs. Hypermitotic meningiomas. Hierarchical clustering of samples based on differential splicing events separated Hypermitotic from Merlin-intact and Immune-enriched meningiomas. The proto-oncogenes Misshapen-like Kinase 1 (MINK1) and Nuclear Auto-antigenic Sperm Protein (NASP) were differentially spliced across WHO grades, DNA methylation groups, and in primary vs. recurrent meningiomas and correlated with recurrence free survival. Differential gene expression analysis revealed alterations in the expression of several splicing factors across methylation groups, including those involved in tumorigenesis (MEX3A, SNRPE, SRSF5).

CONCLUSIONS:

AS promotes differential isoform expression across clinically important DNA-methylation groups of meningiomas. Our analyses capture a splicing signature that correlates with meningioma aggressiveness, identifies prognostic splicing events in known human proto-oncogenes (MINK1, NASP), and uncovers their potential upstream regulators. Validation of how these events impact meningioma tumorigenesis may allow for the development of novel diagnostic tests and therapies targeting AS.
468 Relationship Between Tumor Location and Quality and Extent of Resection in the Surgical Treatment of Myxopapillary Ependymoma
Authors: Joiner Evan F. , Greenwald Phoebe , Neira Justin Anthony , Kostadinov Jane , Khandji Alexander , Mandigo Christopher Eliot , Angevine Peter D. , McCormick Paul C.
Published: March 2023

INTRODUCTION:

Myxopapillary ependymomas (MPE) are benign spinal tumors that present substantial heterogeneity with respect to size, location, and marginal integrity. These factors influence both extent and technique of tumor resection as well as the risk of tumor recurrence and CSF dissemination.

METHODS:

A retrospective review of all patients treated surgically for MPE at a tertiary care center from 1998 to 2021 was performed.

RESULTS:

Fifty-six patients (32 male, 24 female; age 21 to 77 years, mean 45.8 years) were included in the study. Sixty primary surgical procedures were performed (4 patients underwent a second surgery for removal of pre-existing sacral drop metastases). The quality and extent of resection was categorized as en bloc gross total resection (eGTR, n = 15), marginal GTR (mGTR, n = 17), piecemeal GTR (pGTR, n = 6), piecemeal near total resection (pNTR, n = 9), and subtotal resection (STR, n = 13). Fourteen of 15 eGTRs and all 17 mGTRs were accomplished in patients with tumors at or above L3. In contrast, 3/6 pGTRs, 5/9 pNTRs, and 10/13 STRs occurred in patients with tumors below L3 (p < 0.001 for Fisher’s exact test). Tumor recurrence was noted in 1/15 patients who received eGTR, 1/17 who received mGTR, 0/6 who received pGTR, 1/9 who received pNTR, and 9/13 who received STR (p < 0.001).

CONCLUSIONS:

MPEs are heterogeneous neoplasms. The quality and extent of resection is often dictated by tumor location, which in turn correlates with the marginal integrity of the tumor. Tumors located below L3 are more often poorly marginated—allowing for only subtotal or piecemeal resection—while tumors at or above L3 are more likely to be amenable to eGTR or mGTR.
473 Role of Neutrophils and Neutrophil Extracellular Traps in Subarachnoid Hemorrhage in Mice
Authors: Zeineddine Hussein A. , Honarpisheh Pedram , Hong Sungha , Dienel Ari , Thankamanipandit Peeyush , Blackburn Spiros L. , Aronowski Jaroslaw , Mcbride Devin
Published: March 2023

INTRODUCTION:

Aneurysmal subarachnoid hemorrhage (aSAH) continues to be a devastating disease. The role of neutrophils and neutrophil extracellular traps (NETs) have been investigated in other cerebrovascular disorders. Recent evidence suggest that neutrophils might play a role in outcomes after aSAH.

METHODS:

Subarachnoid hemorrhage model: The endovascular perforation model was utilized to induce SAH in mice. Flow cytometry: Flow cytometry technique was utilized to quantify neutrophils. Neutrophils were identified as CD45+Cd11b+Ly6G+ cells. NETosis assay: Neutrophils were assayed for their NETosis potential using a previously described method. The ratio of PMA (SYTOX+) to DMSO (SYTOX+) defined the NETosis induction. RNAseq: RNA sequencing was performed on neutrophils isolated from skull and femur bone marrow. Immunohistochemistry: NETs were assessed using classical IHC techniques and in vivo microscopy. Neurobehavior score: Mice were assessed daily for their behavior score using previously reported techniques.

RESULTS:

Neutrophils infiltrate brain within 24 hours and normalize by day 5. RNAseq demonstrates segregation of skull and femur bone marrow neutrophils following SAH. SAH induces a NETosis phenotype in skull neutrophils. NETs form starting day 1 after injury and persist until at least day 7. Neutrophil depletion and NETs inhibition attenuates early brain injury after SAH. Patients developing DCI have significantly higher blood markers of NETs.

CONCLUSIONS:

Neutrophils infiltrate the brain within the first 24 hours with NETs forming as early as day 1. Depletion of neutrophils and NET inhibition mitigated early brain injury following SAH. Blood markers of NETs are elevated in DCI patients and may be used as predictors of DCI. This highlights NETs as potential therapeutic target for patients with SAH and paves the way for future studies.
476 Technical and Clinical Outcomes in Concurrent Multivessel Occlusions Treated With Mechanical Thrombectomy: Insights from the STAR Collaboration
Authors: Saad Hassan Wajih , Eshraghi Sheila , Howard Brian M. , Buster Bryan Edward , Akbik Feras , Maier Ilko , Goyal Nitin , Starke Robert M. , Rai Ansaar , Fargen Kyle Michael , Psychogios Marios , Jabbour Pascal , DeLeacy Reade , Dumont Travis Michael , Kan Peter , Arthur Adam S. , Crosa Roberto , Gory Benjamin , Spiotta Alejandro M. , Alawieh Ali M. , Grossberg Jonathan Andrew
Published: March 2023

INTRODUCTION:

Endovascular thrombectomy(EVT) has become the mainstay treatment of large vessel occlusion, however its role in the treatment of patients with simultaneous multi-territory occlusions(MVOs) has not been established.

METHODS:

We reviewed the STAR registry and included patient data from 35 stroke centers for EVT performed to treat bilateral anterior or concurrent anterior and posterior circulation occlusions from 2017-2020.

RESULTS:

We included a total of 7723 patients who underwent EVT for acute ischemic stroke. 54 patients (0.7%) underwent EVT for MVOs (mean age 69 ± 12.5; Female 50%). 28% had bilateral and 72% had concurrent anterior and posterior circulations occlusions. We used propensity score matching to match patients with MVOs to another group with single vessels occlusions by age, gender, race, admission NIHSS, baseline mRS score, onset to groin, use of IV-tPA. The rate of recanalization (TICI2B/3), complications, modified Rankin score at 90 days, and mortality was not significantly different between the 2 groups. Multivariate analysis confirmed that MVOs was not a predictor of poor functional outcome, increased symptomatic hemorrhage, or longer procedure time.

CONCLUSIONS:

Compared to single vessel occlusions, EVT in appropriately selected MVOs has similar efficacy and safety profile.
480 Cerebrospinal Fluid Volume Assessed From Clinical T1w-MRI Predicts Functional Outcomes Post-Thrombectomy
Authors: Shamulzai Ahmad , Kawas Mohammad , Kittel Carol , Curry Brian Patrick , Kim Jeongchul , Atcheson Kyle , Whitlow Christopher , Wolfe Stacey Q.
Published: March 2023

INTRODUCTION:

Endovascular treatment (EVT) is recognized as the standard of care for patients with acute ischemic stroke caused by large vessel occlusion (LVO). However, many patients do not achieve functional independence after successful EVT, which may be due to the pre-existing brain atrophy and higher total cerebrospinal fluid volume (CSFV). Prediction of patients who will highly benefit from EVT may be possible using baseline total CSFV as a marker of brain health and reserve.

METHODS:

We performed a retrospective analysis of Wake Forest Baptist Health’s Stroke Thrombectomy and Aneurysm Registry (n = 602), collected between 2015 - 2021. We selected 213 patients (mean age 67.5 ± 14.6, 49.3% female) who had adequate MRI within 14 days of EVT and a record of the modified Rankin scale (mRS) at 90 days post EVT. Clinical T1w images were transformed into high-resolution images using the convolutional neural network SynthSR. Then, FreeSurfer was used to estimate total cranial CSFV including the ventricles and choroid plexus. To correct for head size, total CSFV was adjusted to the estimated total intracranial volume.

RESULTS:

Baseline total CSFV significantly predicted 90-day mRS in an ordinal regression model adjusted for baseline mRS (p < 0.001). After further adjustment for age, sex, smoking history, prior stroke, hypertension, congestive heart failure, hemoglobin A1c, atrial fibrillation, ASPECT score, and other confounders, total CSFV remained an independent predictor of 90-day mRS (p = 0.007).

CONCLUSIONS:

This study elucidates the clinical implications of pre-existing brain health and reserve in the setting of acute ischemic strokes to aid clinicians in treatment decisions impacting prognosis. Increased total CSFV correlates with increased brain frailty and poorer functional outcomes after mechanical thrombectomy, which may ultimately attenuate its benefit.
485 Evaluating Surgical Arthrodesis With Novel MRI Grading Score
Authors: Mazur-Hart David , Larson Erik Werner , Gerges Christina , Nugent Joseph Girard , Pettersson David , Ross Donald A.
Published: March 2023

INTRODUCTION:

Diagnostic imaging following cervical fusion often involves magnetic resonance imaging (MRI) to evaluate neural structures and computed tomography (CT) and/or dynamic radiographs to evaluate instrumentation and arthrodesis. CT and radiographs use ionizing radiation that increases risk for malignancy. Using MRI alone would protect patients and decrease healthcare utilization.

METHODS:

Single institution retrospective study evaluating patients who received postoperative CT and MRI following ventral cervical fusion procedures. Radiographic standards were used to evaluate for arthrodesis or pseudo-arthrosis. Blinded observers evaluated signal intensity using a region of interest (ROI) over the instrumented disc space, homogenous cerebral spinal fluid (CSF), and distal uninstrumented vertebral body (VB). A quotient (ROIinterspace/ROICSF and ROIinterspace/ROIVB) was used to create T1- and T2-interspace interbody scores (IIS). Additionally, T1 hypointense lines along endplates and facet joints were evaluated for degree of discontinuity.

RESULTS:

Study included 60 patients (50% female) with 110 instrumented levels and mean age 51.7 years-old. For T1-weighted MRI, median T1-IISCSF for arthrodesis was 176.2 compared to 130.9 for pseudo-arthrosis (p < 0.0001) while T1-IISVB for arthrodesis was 68.5 and pseudo-arthrosis was 52.7 (p < 0.0001). For T2-weighted MRI, median T2-IISCSF for arthrodesis was 27.7 and 14.2 for pseudo-arthrosis (p < 0.0001) while T2-IISVB for arthrodesis was 67.9 and 41.0 for pseudo-arthrosis (p < 0.0001). Median T1 hypointense discontinuity was graded at the endplates, left facet, and right facet as 1.5, 0.25, and 0.5 compared to pseudo-arthrosis as 1.0, 0.0, and 0.0, respectively (p < 0.0001, p = 0.002, and p = 0.001). The greatest area under the curve (AUC) after receiver operator characteristic (ROC) analysis was T1-IISVB (0.7743).

CONCLUSIONS:

We describe a novel scoring system that may help determine arthrodesis versus pseudo-arthrosis on MRI following ventral cervical fusion. Postoperative symptomatic patients may only require MRI for workup, which would protect patients from harm while decreasing healthcare utilization.
495 Impact of Postoperative Fatigue Following Minimally-Invasive Lumbar Spine Surgery
Authors: De Biase Gaetano , Chen Selby G. , Bojaxhi Elird , Garcia Diogo P. , Quinones-Hinojosa Alfredo , Abode-Iyamah Kingsley O.
Published: March 2023

INTRODUCTION:

Postoperative fatigue, a feeling of debilitating tiredness and loss of energy, is a distressing symptom and can have a major impact on the patient’s quality of life after surgery. Fatigue may be one of the main complaints after surgery and may last much longer than pain, preventing return to normal function and activity.

METHODS:

We surveyed patients that underwent minimally-invasive lumbar spine surgery under general anesthesia (laminectomy with or without fusion) within the past year. A five-point Likert scale (very much, quite a bit, somewhat, a little bit, not at all) was used to assess the extent of fatigue during the first postoperative month, its impact on QOL, and ADLs.

RESULTS:

The survey was completed by 100 patients, 61% were male, with mean age 64.6 ± 12.5 years (range 28-87), 31% underwent an MIS-TLIF, 69% a lumbar laminectomy. During the first postoperative month 45% of patients referred significant fatigue (very much or quite a bit); for 31% of patients fatigue significantly impacted their QOL; and significantly limited their ADLs in 43% of patients. MIS-TLIF was associated with higher rate of postoperative fatigue compared to laminectomy, 61.3% versus 37.7%, p=0.02. Patients 65 years old or older had higher rates of fatigue compared to younger patients, 55.6% versus 32.6%, p = 0.02. We did not observe a statistically significant difference in postoperative fatigue between male and female patients.

CONCLUSIONS:

Our study revealed a substantial incidence of postoperative fatigue in patients that underwent minimally-invasive lumbar spine surgery under general anesthesia, with a significant impact on their QOL and ADLS. There is a need to research new strategies to reduce fatigue after spine surgery.
503 Stimulation of the Paraventricular Nucleus Activates Brown Adipose Tissue via Local GABA Release: A Novel Target for the Treatment of Obesity
Authors: Siler Dominic Aaron , Mota Clarissa , Morrison Shaun , Burchiel Kim J. , Madden Chris
Published: March 2023

INTRODUCTION:

Sympathetic activation of brown adipose tissue (BAT) has shown significant promise in preclinical studies to elicit long term weight loss and reversal of type 2 diabetes however it is inhibited in obese individuals.

METHODS:

Rats were anesthetized and monitored for body temperature, BAT temperature, expired CO2, mean arterial pressure, and heart rate. Postganglionic BAT sympathetic nerve activity (SNA) was recorded from the interscapular BAT pad. Stimulating electrode and micropipette were placed steroeotactically in the PVN. Stimulation pulses at an intensity of 100 µA at 100 Hz for 5 minutes were delivered. Changes in BAT SNA and physiology were compared with and without stereotactically injected 500 µM bicuculline, a GABAA receptor antagonist.

RESULTS:

Stimulation of the PVN increased BAT SNA compared to no stimulation (411.7 ± 75.8% baseline vs 98.18 ± 1.4% baseline n = 5; P < 0.05) along with BAT temperature (35.8 ± 0.8°C vs 34.2 ± 0.7°C, n = 5, P < 0.001), expired CO2 (4.7 ± 0.6% vs 4.2 ± 0.5%, n = 5, P < 0.05) indicating increased metabolic rate. There was no change in blood pressure, body temperature, or paw temperature suggesting no change in sympathetic tone. Heart rate increased (476 ± 21 bpm vs 429 ± 23 bpm, n = 5, P < 0.01) consistent with increased metabolic demand. Microinjection of 500 µM bicuculline into the PVN prevented stimulated activation of BAT SNA.

CONCLUSIONS:

Stimulation of the PVN increases BAT activation and basal metabolic activity in the absence of cold-stimulus with minimal off-target effects on systemic sympathetic tone and may be a viable therapeutic target for stimulation of BAT activity to treat obesity and type 2 diabetes.
515 Conserved Theta-Gamma Coupling During Speech Production in Glioma
Authors: Surapaneni Akhil , Aabedi Alexander Arash , Kaur Jasleen , Brang David , Kuo John S. , FAANS FACS , Millán José del R. , Hervey-Jumper Shawn L.
Published: March 2023

INTRODUCTION:

It has been shown recently that infiltration of gliomas into healthy neural tissue alters local neuronal spiking patterns, leading to circuit dysfunction. It is unknown, however, if glioma infiltration also impacts the coordination of local neuronal computations with other networks during behavioral tasks. Cross-frequency coupling of high gamma (HG) (80-150 Hz) amplitude with theta (Th) (4-7Hz) phase is a well-established mechanism for this type of neural integration.

METHODS:

Patients (n = 13) with dominant hemisphere perisylvian gliomas were intraoperatively implanted with an ECoG grid and performed a picture naming task. Electrodes overlying regions of tumor infiltration and those overlying normal parenchyma were identified using the T2-FLAIR signal. Following a widely accepted method, Kullback–Leibler (KL) divergence of HG amplitude distribution over Th phases from a uniform distribution was used to quantify Th-HG coupling of each electrode during speech production. Statistical significance was determined by comparing to a null distribution of KL divergence values corresponding to the original HG time series randomly cut in ten places and permuted, while preserving the theta time series. This destroys the cyclostationarity of theta-gamma coupling while preserving other non-stationarities.

RESULTS:

43 out of 114 electrodes overlying normal parenchyma and 104 out of 300 electrodes overlying tumor-infiltrated regions exhibited significant Th-HG coupling after FDR correction. Electrodes overlying tumor regions and normal parenchyma had similar spatial coverage at the group level. Electrodes with Th-HG coupling at a preferred theta phase of π radians exhibited greater coupling. No significant difference in KL divergence was found between tumor-overlying electrodes and non-tumor overlying electrodes at the group level.

CONCLUSIONS:

Th-HG phase-amplitude coupling is preserved in glioma-infiltrated brain tissue during speech production. This suggests that glioma-infiltrated tissue participates in the coordination of spatially and temporally distributed processes during complex behaviors.
527 Multicentric Evaluation of Stereotactic Radiosurgery for Koos Grade IV Vestibular Schwannoma in Young Patients
Authors: Dumot Chloe , Pikis Stylianos , Mantziaris Georgios , Xu Zhiyuan , Lunsford L. Dade , Sheehan Jason P. ,   International Radiosurgery Research Foundation contributors
Published: March 2023

INTRODUCTION:

Koos IV vestibular schwannoma (VS) are preferably treated by surgery. However, SRS can be an alternative for patients with contraindications or who refuse surgery. SRS for Koos IV patient younger than 45 years old has not been previously studied and could be associated with more complications.

METHODS:

This is a retrospective multicentric study, performed under the International Radiosurgery Research Foundation. Patients 45 years old, treated primarily for a Koos IV VS with single-session SRS, presenting with non life-threatening or incapacitating symptoms, with a follow-up ≥1 years were included.

RESULTS:

176 patients with a median age of 36 years (IQR 9) and a median tumor volume of 9.3 cm3 (IQR 4.7) were included. Before SRS, serviceable hearing, facial nerve weakness (House-Brachman >1) and trigeminal neuropathy was present in 51.7%, 8.5%, and 34.1% respectively. The median prescription dose was 12Gy (IQR 0.5). At a median follow-up of 3.1 years (IQR 4.5), tumor stability and regression were 38.9% and 54.3%, respectively. The 5- and 10-year progression-free rate was 90.9% and 86.7%. Early tumor enlargement occurred in 10.9% of cases. The probability of serviceable hearing preservation at 5- and 10-years was 56.8% and 45.2%, respectively. The probability of improvement or preservation of facial nerve function was 95.7% at 5 and 10-years. Adverse radiation effects were noted in 19.9%, 6 of them where managed with surgical resection of the VS. New-onset hydrocephalus occurred in 4.0%.

CONCLUSIONS:

Single-session SRS in selected Koos IV VS can be an alternative to surgery in a selected group of patients 45 years old. Long-term follow-up is warranted.
554 Cerebral Emboli Detection Using Robotic Transcranial Doppler With Artificial Intelligence During Transcatheter Aortic Valve Replacement - A Novel and Autonomous Neuromonitoring Tool
Authors: Baig Ammad , Manion Christopher , Khawar Wasiq , Donnelly Brianna , Monteiro Andre , Iyer Vijay , Levy Elad I. , Siddiqui Adnan Hussain
Published: March 2023

INTRODUCTION:

Periprocedure ischemic stroke remains a serious complication in patients undergoing transcatheter aortic valve replacement (TAVR).

METHODS:

Consecutive patients undergoing TAVR were prospectively enrolled in the study. Basic demographics and procedural details, such as protection device used, type of aortic valve used, and any intraprocedure or postprocedure (<30 days) complications, were recorded. Continuous variables were analyzed by two-sample Mann-Whitney t-test and categorical variables by chi-square or Fisher test.

RESULTS:

Thirty-one patients were prospectively enrolled (mean age=79.9±7.6 years; men=16 [51.6%]). Hyperlipidemia was present in 27 patients (87.1%), followed by hypertension in 25 (80.6%). Mean aortic valve area was 0.7 cm2. Mean aortic-ventricular gradient was 43 mmHg (interquartile range 31.5-50 mmHg). The protection device was used in 16 cases. A significantly lower emboli count was observed in the protection group (means of 470.38 vs. 693.33 in the non-protection group; P=0.01). Emboli counts during valve positioning and implantation were significantly different as well (means of 249.92 protection vs. 387.5 non-protection; P=0.01). One (4%) nonfatal stroke was seen postoperatively in the protection group.

CONCLUSIONS:

We describe use of a novel real-time intraoperative neuromonitoring tool in patients undergoing TAVR. Significantly fewer HITS were detected in the protection group. Valve positioning and implantation was identified as the most significant stage in terms of intraprocedural HITS.
562 Investigation of Cerebral Vessel Geometric Morphometrics for Prediction of Mechanical Thrombectomy First Pass Outcome
Authors: Santo Briana , Monteiro Andre , Sarayi Seyyed , Donnelly Brianna , Baig Ammad , Waqas Muhammad , Siddiqui Adnan Hussain , Levy Elad I. , Tutino Vincent
Published: March 2023

INTRODUCTION:

Vessel tortuosity is a major factor in successful first pass outcomes for mechanical thrombectomy (MT), but previous methods to quantify tortuosity are not accurate enough to predict outcome. We investigated a new method for vessel characterization and outcome prediction based on geometric morphometrics (GMM).

METHODS:

Vessels and clots were manually segmented and reconstructed from pre-treatment CTA and nCCT images (n=5 cases). The vasculature corresponding to the ICA and MCA from the affected hemisphere was isolated, and centerlines were engineered as curved landmarks. MorphoJ, a GMM software, was used to complete generalized Procrustes and principal component (PC) Analysis that included registration of patient geometries, calculation of average morphology and landmark variation, and identification of anatomical landmarks differentiating MT outcomes. Morphometrics were compared against local and overall tortuosity by measuring the separability of and cohesion within outcome classes.

RESULTS:

GMM produced two PCs, which described local variation in M1 (PC1) and the ICA (PC2). When compared against vessel tortuosity features, GMM PCs increased the distance between outcome classes (first pass effect vs. no first pass effect), improving separability by 23.6%. Further, GMM PCs increased the compactness/cohesion of outcome classes, reducing cumulative distance between failures by 50% and successes by 9.4%.

CONCLUSIONS:

GMM analysis of pre-treatment vessel characteristic highlights regional variation in M1 as a strong indicator of MT failure, and suggests that GMM has the potential to better predict MT outcome than ICA tortuosity alone. Investigation of more complex vessel morphometry through feature engineering is needed.
622 Differences in Healthcare Resource Utilization After Surgery for Metastatic Spinal Column Tumors in Safety-Net Hospitals
Authors: Elsamadicy Aladine A. , Koo Andrew B. , David Wyatt , Reeves Benjamin , Sherman Josiah , Craft Samuel , Hersh Andrew , Duvall Julia , Lo Sheng-fu , Shin John H. , Mendel Ehud , Sciubba Daniel M.
Published: March 2023

INTRODUCTION:

Safety Net Hospitals (SNH) are those which serve an especially high proportion of Medicaid, uninsured, and charity care patients, though few have studied the impact of SNH status on healthcare resource utilization for patients with metastatic spinal column tumors.

METHODS:

A retrospective cohort study was performed using the 2016-2019 National Inpatient Sample database. Adult patients undergoing surgery for metastatic spinal column tumors were identified using ICD-10-CM codes. Admissions were dichotomized by SNH status, defined as the top quartile of Medicaid and uninsured burden. Hospital characteristics, patient demographics, comorbidities, intraoperative variables, and outcomes were assessed. Multivariate logistic regression analyses were used to identify predictors of extended LOS, non-routine discharge, and increased cost.

RESULTS:

Of the 11,505 patients identified, 24.0% (n = 2,760) were treated at a SNH and 76.0% (n = 8,745) were treated at a Non-SNH (N-SNH). Compared to patients treated at N-SNH, a greater proportion of patients at SNH were African American, male, and of lower income quartile. Number of comorbidities (p = 0.324), intraoperative complications (p = 0.488) and postoperative complications (p = 0.064) were similar between cohorts. Patients treated at SNH typically experienced greater LOS (SNH: 12.3 ± 11.3 days vs. N-SNH: 10.1 ± 9.5 days, p<0.001), though total cost of admission (SNH: $58,804 ± 39,088 vs. N-SNH: $54,569 ± 36,781, p = 0.550), non-routine discharge disposition (SNH: 48.2% vs. N-SNH: 48.4%, p = 0.715) and mortality rate (SNH: 3.1% vs. N-SNH: 2.7%, p = 0.629) were similar. On multivariate analysis, SNH status independently predicted extended LOS [OR: 1.41, p = 0.009], but not non-routine discharge [OR: 0.97, p = 0.773] or increased cost [OR: 0.93, p = 0.655].

CONCLUSIONS:

Our study suggests that the quality of care provided by SNH is largely similar to that provided by non-SNH for patients undergoing surgical intervention of metastatic spinal column tumors
646 Publication Speed Across Neurosurgical Journals: A Bibliometric Analysis
Authors: Hanna Jubran Jubran , Scherschinski Lea , Park Marian , Rhodenhiser Emmajane , Benner Dimitri , Ibrahim Sufyan , Karahalios Katherine , Singh Rohin , Maher Hulou M. , Graffeo Christopher S. , Lawton Michael T.
Published: March 2023

INTRODUCTION:

Many factors influence an author’s choice for journal submission, including the journal impact factor and publication speed. These bibliometric data points, amongst others, have not yet been assessed in neurosurgical research.

METHODS:

Eight neurosurgical journals were analyzed for original articles, collected via randomized sampling per issue per year from 2016-2020. Publication speed data was gathered from published articles. Journal Impact Factors were gathered using Clarivate Journal Citation Reports. Spearman’s correlation analysis was used to analyze the findings.

RESULTS:

A total of 1617 original articles and systematic reviews across 8 neurosurgical journals were reviewed. The mean (standard deviation; SD, range) time from submission to print publication (SP) in neurosurgery journals is 344 (190) days, while the submission to acceptance (SA) time is 130 (104) days, acceptance to online print (AO) time is 76 (61) days, and the online publication to print publication (OP) is 137 (114) days. Most articles were from authors from the United States (n = 833; 52%), with the second and third highest contributions coming from China (n = 100; 6%) and Japan (n = 83, 5%) respectively. The top three neurosurgical topics published were spine (n = 417; 26%), vascular (n = 316; 20%) and oncology (n = 275; 17%). There were significant correlations across all determinants of publication speed and journal Impact Factors (SP: r = 0.457, SA: r = 0.204, AO: 0.481, OP: 0.317, p < 0.001).

CONCLUSIONS:

Neurosurgical journal publication speeds vary between journals and are significantly correlated with the journal’s impact factor. The majority of neurosurgical research in the past five years has been focused in spine, vascular, and oncology fields and has originated from the United States. The information on individual journals could serve as a guide for publishing neurosurgeons to determine the appropriate journal for submission.
659 Minimally Invasive Surgery for Spinal CSF-Leaks in Spontaneous Intracranial Hypotension—Technical Aspects and Complications
Authors: Beck Juergen , Hubbe Ulrich , Klingler Jan-Helge , Rölz Roland , Volz Florian , Urbach Horst , Fung Christian
Published: March 2023

INTRODUCTION:

Spinal cerebrospinal fluid (CSF)-leaks cause spontaneous intracranial hypotension (SIH). In persisting symptoms despite treatment, surgical closure of spinal CSF-leaks is the treatment of choice.

METHODS:

Since April 2019 SIH patients were operated using the minimal invasive technique of tubular retractors. Leaks were sealed using an interlaminar dorsal access and if necessary a transdural route. Neuromonitoring was used for ventral leaks in the first 16 cases. The primary outcome was the benefit of surgery with respect to orthostatic symptoms; secondary outcome was the occurrence of complications.

RESULTS:

Between April 2019 and December 2020 we included 58 patients, mean age 46 years (IQR 36-55), 65% female, with the diagnosis of SIH. We treated 38 ventral leaks, 17 dorsal/lateral leaks, 2 CSF-venous fistulas. In all but two patients (96.6%) the leak could be approached, identified and closed via the tubular retractor. Leaks were visualized via a transdural approach, after cutting the dentate ligament and lateralization of the ventral dura. Microspurs were removed and leaks were closed by sandwich patch using a fibrin sealant patch (ventral leaks) or clipping of the respective nerve root (lateral leaks, CSF-venous fistula). At a median follow up of 21.5 months (IQR 16-28), eight patients were lost to follow up and 45 reported a benefit from surgery with respect to orthostatic symptoms. Mild permanent neurologic deficits occurred in 1.7%, the revision rate due to persisting or recurring leak was 3.4% and the overall revisioin rate was 10.3%.

CONCLUSIONS:

Minimally invasive surgery using tubular retractors of 18-20mm diameter can be safely and effectively performed for closure of spinal dural CSF-leaks in specialized centers.
664 Use of Local Surgical Site Morselized Autograph to Perform Minimally Invasive Transforaminal Lumbar Interbody Fusion to Improve Outcome
Authors: Perez-Cruet Mick J. , Torre Ramiro Antonio Perez de la , Ramanathan Siddharth , Chieng Leon , Black Jordan , Rapp Aaron , Mong Eric
Published: March 2023

INTRODUCTION:

MI-TLIF has become one of the primary approaches for treating refractory low back pain. Patient outcomes are related to fusion rates. A critical analysis of the impact of surgical site morselized autograph bone (MAB) on patient reported outcomes undergoing MI-TLIF has not been analyzed.

METHODS:

A retrospective analysis of 215 patients who underwent MI-TLIF using MAB. Variables analyzed included age, gender, follow-up period, comorbidities, number/levels of stenosis, estimated blood loss, surgical time, complications in the immediate postoperative period, clinical scales including VAS (Visual Analogue Scale), ODI (Oswestry Disability Index) at 3, 6, 12, 24 -months.

RESULTS:

Average age was 63.8±12.7 years and average BMI was 29.4±6.1 kg/m2 with average follow-up 19.4+/-11.4 months. Co-morbidities included: diabetes (n=34 (15.8%)) and current or former smoker (n = 61 (28.4%)). Pathogy treated included 156 patients with spondylolisthesis (n = 139, grade 1; n = 17, grade 2) and 122 patients with concomitant stenosis with grade 1(n = 20), 2(n = 15), and 3(n = 87). No major operative adverse events were noted, with 2 patients with postoperative infections. Postoperative VAS showed statistically significant improvements at 3 weeks, 1 year, and 2 years compared to baseline levels (p < 0.00001 for all). Improvements in ODI scores were statistically significant compared to baseline at 3 months (p = 0.03) and 2 years (p = 0.016). Of the 54 patients that had comorbid scoliosis, Cobb angle improved from 20±10.6 preoperatively to 16 ± 10.5 postoperatively (p = 0.27). No long-term adverse events occurred. Fusion rate was greater than 95%.

CONCLUSIONS:

MI-TLIF using MAB was highly cost effective, had low complication rates, and significantly improved patient reported outcomes.
672 Diffusion Basis Spectrum Imaging Provides Insights into Cervical Spondylotic Myelopathy Pathology
Authors: Zhang Justin , Javeed Saad , Greenberg Jacob K. , Jayasekera Dinal , Song Chunyu , Dibble Christopher , Blum Jacob , Sun Peng , Song Sheng-Kwei , Ray Wilson Zachary
Published: March 2023

INTRODUCTION:

Diffusion basis spectrum imaging (DBSI) is a non-invasive quantitative imaging modality that may improve understanding of cervical spondylotic myelopathy (CSM) pathology through detailed evaluations of spinal cord microstructural compartments.

METHODS:

A single-center prospective cohort study enrolled fifty CSM patients and twenty controls from 2018-2020. All patients underwent clinical evaluation and diffusion-weighted MRI, followed by diffusion tensor imaging (DTI) and DBSI analyses. Diffusion-weighted MRI metrics assessed white matter integrity by fractional anisotropy, axial diffusivity, radial diffusivity, and fiber fraction. In addition, DBSI further evaluates extra-axonal changes by isotropic restricted and non-restricted fraction. Including an intra-axonal diffusion compartment, DBSI improves estimations of axonal injury via intra-axonal axial diffusivity. Patients were categorized into mild, moderate, and severe CSM using mJOA classifications. Imaging parameters were compared among patient groups using independent-samples t-tests and ANOVA.

RESULTS:

Twenty controls, 27 mild (mJOA 15-17), 12 moderate (12-14) and 11 severe (0-11) CSM patients were enrolled. All patient-reported outcome measures were worse in CSM patients (all p < 0.001). DTI and DBSI fractional anisotropy, axial diffusivity, and radial diffusivity were significantly different between control and CSM patients (p < 0.05). DBSI fiber fraction, restricted fraction, and non-restricted fraction were significantly different between groups (p < 0.01). DBSI intra-axonal axial diffusivity was lower in mild compared to moderate (mean difference [95% CI]: 1.1 [0.3, 2.1], p < 0.01) and severe (1.9 [1.3, 2.4], p < 0.001) CSM.

CONCLUSIONS:

DBSI offers granular data on white matter tract integrity in CSM that provide novel insights into disease pathology, supporting its potential utility as a biomarker of CSM disease progression.
744 Reducing Implicit Bias in the Neurosurgery Application and Interview Process
Authors: Cobourn Kelsey Diva , Breton Jeffrey Michael , Dowlati Ehsan , Wong Georgia , Pivazyan Gnel , Nair Nathan
Published: March 2023

INTRODUCTION:

Each year, Neurosurgery residency programs aim to match the best and brightest applicants aspiring to join the field. Traditionally, metrics such as USMLE Step 1 and 2 scores, publications, and medical school grades have played a key role in determining who is interviewed, the interviewers’ impression of the candidates, and subsequently who is most likely to match. However, these evaluative tools are known to reflect biases in the medical and medical education systems, potentially overlooking diverse applicants well-suited for a career in neurosurgery.

METHODS:

During the 2020-2021 and 2021-2022 residency application cycles, our program instituted a new process for reviewing applications, conducting interviews, and generating a final rank list. Each application was reviewed by attending and resident reviewers, who were blinded to potentially biasing information including pictures and board scores. From this review, selected applicants were interviewed using a set of standardized questions, designed to evaluate specific domains essential for success in neurosurgery. Linear regression was performed to determine correlation between traditional metrics and domain-based interview scores and final rank.

RESULTS:

137 applicants were interviewed. There was no significant correlation between rank and Step 1 (p = 0.47, R2 = 0.003) or Step 2 scores (p = 0.16, R2 = 0.014).Interview scores lacked statistically significant association with Step 1 scores (p=0.10, R2=.02), but were found to correlate with Step 2 scores (p = 0.02, R2 = .05).

CONCLUSIONS:

In our two-cycle experience using this new system, we found no correlation between applicants’ Step 1 scores and their interview scores or final rank list position. We propose this as one alternative method to historically biased tools for evaluating neurosurgery applicants.