bluuebunny/crossref_metadata_2025 huggingface dataset:
329 Same Day Discharge After Craniotomy for Brain Tumor Resection: Enhancing Patient Selection Through a Prognostic Scoring System
Authors: Levy Adam , Merenzon Martin Andres , Bhatia Shovan , Costello Meredith , Di Long , Lu Victor M. , Morell Alexis Andres , Chand Daggubati Lekhaj , Shah Ashish H. , Komotar Ricardo Jorge , Ivan Michael E.
Published: March 2024

INTRODUCTION:

Neurosurgery, among other surgical fields, is in the midst of a shift in patient management with enhanced recovery and same day discharge protocols slowly becoming more popular and feasible. While such protocols reduce risk of nosocomial complications and improve patient satisfaction, appropriate patient selection remains an area of debate.

METHODS:

Three arms of analysis were carried out. First, clinical data of SDD patients was prospectively collected between August 2021 and August 2022. In parallel, a retrospective analysis of patients who qualified for SDD but were excluded at surgeon clinical discretion over the same period was performed. Third, a comparative analysis of the pilot and follow-up studies was done from which a clinical scoring system for patient selection was derived.

RESULTS:

Over the length of the study, 31 of 334 patients were selected for SDD while 59 qualified by previously defined criteria but were not selected at the surgeon’s discretion. There was no difference in outcomes between the two groups nor any post-operative complications among the SDD group within 30 days of surgery. Preoperative clinical characteristics found to be significantly different between the two cohorts (Left sided lesion, extra-axial pathology, prior treatment of brain tumor, and tumor volume < 11.75 cm3) were included in a predictive scoring system for successful SDD. The system was found to significantly predict high or low likelihood for successful SDD when tested on the mixedprospective cohort.

CONCLUSIONS:

This study provides a straightforward clinical scoring system for appropriate selection of candidates for SDD after craniotomy for brain tumor resection. The application of this clinical tool aims to aid clinicians in appropriate admission course selection and builds on the growing literature surrounding same-day and outpatient cranial neurosurgery.
338 Getting Ahead of the Disparities Curve: Increasing Capture Rate of Comorbidities Which Would Exacerbate Socioeconomic Disparities in a Value-Based System
Authors: Patel Pious D. , Khanna Omaditya , Salwi Sanjana , Metzinger Matthew , Rosenwasser Robert H.
Published: March 2024

INTRODUCTION:

Value-based systems will place financial risk on providers. If these payments are not adequately adjusted for comorbidity burden, systems will be disincentivized to treat marginalized socioeconomic groups who have disproportionately high comorbidity burden.

METHODS:

Comorbidity-focused note-writing templates were incorporated into the physicians’ workflow within Jefferson University Hospital’s Neurosurgery Department. A list of high-risk comorbidities was identified and incorporated into the top of each note. Emphasis was given to comorbidities which have high historical impact on mortality and which are commonly overlooked in the acute neurosurgical decisionmaking process (e.g. obesity). The selected comorbidities were populated into the top of every note which included treatment plans for each condition. The process measure included the percentage of notes in compliance with the template. The outcome measures were expected mortality (composite variable representing comorbidity burden) and the capture rate of major comorbidities within the coding process. Measures were compared between one full year pre and post-intervention. Coders were blinded to the presence of our intervention.

RESULTS:

There was 100% compliance after the second week post-intervention (as measured by full audit of all notes written). There was a 44% (3.4% to 4.9%) improvement in expected mortality for the department’s encounters. There was an increased capture rate for several major comorbidities which are disproportionately associated with marginalized socioeconomic groups. These included malnutrition (233% increase, from 3% to 10%), coagulopathies (71% increase from 7% to 12%), obesity (50% increase from 22% to 33%), congestive heart failure (43% increase from 7% to 10%), hypertension (31% increase from 13% to 17%), and deficiency anemias (31% increase from 16% to 21%).

CONCLUSIONS:

We present a low-cost framework to increase capture rate of high-risk comorbidities which traditionally contribute to socioeconomic disparities.
365 Outcomes of Circumferential Minimally-Invasive Technique Versus Open Technique in Adult Spinal Deformity Surgery Patients Over 80 Years of Age: A Propensity-Matched Analysis
Authors: Tretiakov Peter S. , Passias Peter G. , Uribe Juan S. , Alan Nima , Le Vivian , Dave Pooja , Mir Jamshaid M. , Lafage Renaud , Line Breton G. , Wang Michael Y. , Okonkwo David O. , Anand Neel , Fessler Richard G. , Fu Kai-Ming G. , Nunley Pierce D. , Park Paul , Turner Jay D. , Kanter Adam S. , Mundis Gregory M. , Chou Dean , Ames Christopher P. , Hart Robert A. , Smith Justin S. , Shaffrey Christopher I. , Schwab Frank , Bess Shay , Lafage Virginie , Eastlack Robert , Mummaneni Praveen V. , Burton Douglas C. , Das Ankita ,   International Spine Study Group
Published: March 2024

INTRODUCTION:

Circumferential minimally-invasive surgery (cMIS) techniques in ASD surgery may provide benefit in reducing physiologic burden, but the utility of such surgeries in patients greater than 80 years of age has not been assessed.

METHODS:

Operative ASD patients 18yrs with complete pre-(BL) and 2-year(2Y) data were assessed. Patients aged =80years were isolated and compared by surgical technique: Open vs cMIS. BL and peri/post-operative factors were assessed using ANOVA and Bonferroni-adjusted ANCOVA while controlling for BL CCI and posterior levels fused. Propensity score matching (PSM) was used to align cMIS vs Open groups by BL CCI, C7-S1 SVA, PI-LL, and C7PL.

RESULTS:

174 ASD patients were included (62.85 ± 13.93 years, 75.7% female), split evenly between cMIS and Open. 19.5% (n = 34) were octogenarians; 29.4% operated via cMIS vs 70.6% Open. At baseline, patients were comparable in gender, BMI, and history of spine surgery (all p > .05). At BL, frailty scores were comparable (both p > .05). Post-operatively, Open patients reported higher SRS-22 Appearance and Mental domain scores (both p < .005), and were more likely to reach MCID in both domains by 2Y (p = .025, .024, respectively). In terms of post-operative complications, cMIS patients were more likely to require reoperation for radiographic sagittal imbalance by 2Y when controlling for CCI and levels fused (20.0% vs 8.3%, p < .001). By 2Y, there were no recorded deaths in the cMIS nor Open octogenarians.

CONCLUSIONS:

Our comparison of octogenarian adult spinal deformity patients undergoing circumferential minimally-invasive versus open surgery demonstrates that while cMIS patients benefit from decreased blood loss, operative time, and SICU and hospital length of stay, both Open and cMIS patients benefit from similar improvement in patient-reported outcomes. Likewise, Open technique, though more invasive, may also reduce the risk for reoperation due to radiographic instability by 2Y post-operatively.
378 Meningiomas Causing Bony Hyperostosis Upregulate Cell Adhesion, Bone Mineralization, and Bone Development Gene Signatures
Authors: McDonald Malcolm F. , Khan Basit , English Collin , Chang Andrew , Harmanci Arif , Harmanci Akdes , Klisch Tiemo , Patel Akash J.
Published: March 2024

INTRODUCTION:

Meningiomas are the most common primary intracranial tumor. Some meningiomas cause hyperostosis of the adjacent bone, affecting surgical approach.

METHODS:

Two hundred twelve meningioma MRIs were reviewed by a neuroradiologist to classify location and hyperostosis or bone involvement. These tumors were bulk RNA sequenced and analyzed with gene sets enrichment analysis (GSEA), gene ontologies (GO), and differentially expressed genes (DEGs).

RESULTS:

Sixty-seven meningiomas had hyperostosis detected in imaging compared to 145 without it. Meningiomas with hyperostosis occurred most commonly in the sphenoid wing and lateral skull base and relatively less commonly in the clinoidal and clival region (p-val = 0.033, Fisher’s Exact). Looking at the distribution throughout MenG groups, a multi-omic classifier used to predict recurrence, meningiomas with hyperostosis occurred more frequently in the MenG A and MenG C groups compared to MenG B group (p-val = 0.0299, Fisher’s Exact). This may reflect previously described similarity in transcriptional signatures of group A and C. GO analysis revealed upregulation of skeletal system development, peptide breakdown, cell adhesion, and collagen biological processes in hyperostotic tumors (a.,p-val < 0.05), and downregulation of synaptic signaling and receptor activity (b.,p-val < 0.05). When analyzing only genes that were significantly upregulated (padj < 0.05), GOs related to skeletal system development, cellular movement, and hydrogen peroxide processing were upregulated. Alternatively, synaptic transport and negative regulation of peptide breakdown were downregulated. Specific upregulated genes include MEPE, a bone mineralization gene, and cell migration genes like NYAP2, TNS4, and GPM6A (Log2FC > 1, padj < 0.05).

CONCLUSIONS:

Meningiomas with hyperostosis occurred more frequently in the sphenoid wing and lateral skull base. MenG B tumors were least likely to cause hypoerostosis, Meningiomas causing hypoerostosis have unique transcriptional signatures related to bone involvement and cell motility, matching their invasive phenotype.
384 BOLD Asynchrony Reveals Tumor Burden in IDH-Wildtype Gliomas
Authors: Yoh Nina , Petridis Petros , Chokran Cole , Kotidis Corina , Bruce Jeffrey N. , Canoll Peter D. , Grinband Jack
Published: March 2024

INTRODUCTION:

IDH-wildtype gliomas are aggressive, highly invasive, and invariably fatal. Maximal safe resection of tumors is the primary goal in glioma surgery, as it has been associated with improved survival and better outcomes. However, there is no clinically accepted method for identifying the extent of tumor burden in these neoplasms. This uncertainty poses a challenge for clinicians who must balance tumor removal with the sparing of healthy brain.

METHODS:

Forty stereotactically-localized biopsies were obtained during open surgical resection from twenty treatment-naÏve patients with IDH-wildtype gliomas who received standard-of-care preoperative imaging as well as echo-planar resting-state BOLD fMRI. Signal intensity for BOLD asynchrony and standard-of-care imaging was compared to cell counts of total cellularity (H&E), tumor density (Sox2), cellular proliferation (Ki67), and neuronal density (NeuN), for each corresponding sample.

RESULTS:

BOLD asynchrony was directly related to tumor density as well as cellular proliferation and inversely related to neuronal density. Peritumoral regions that appeared normal on standard-of-care imaging but with elevated BOLD asynchrony showed elevated tumor burden on histology.

CONCLUSIONS:

BOLD asynchrony is a novel imaging technique that can elucidate tumor burden that is not observable on standard-of-care imaging. Including BOLD asynchrony in preoperative planning can provide more accurate margins for tumor resection, which may improve patient outcomes and overall survival.
405 The Impact of Cerebral Revascularization on Pial Collateral Flow in Patients With Moyamoya Disease Using Quantitative Magnetic Resonance Angiography
Authors: Santhumayor Brandon , White Timothy G. , Rivera Moses , Ryu Brendan Hanil , Golombeck David , Turpin Justin , Dehdashti Amir R. , Langer David J.
Published: March 2024

INTRODUCTION:

Moyamoya disease (MMD) is a chronic steno-occlusive disease primarily of the anterior circulation leading to significant pial collateralization. Changes in the distribution of intracranial blood flow after revascularization surgery are not well understood.

METHODS:

We conducted a retrospective chart review of 46 patients with unilateral MMD who underwent cerebral revascularization from 2011-2019. Patients who underwent pre- and post- QMRA NOVA were included in the study. Flow was measured at the M1 segment of the middle cerebral artery (MCA), P2 segment of the posterior cerebral artery (PCA), and A2 segment of the anterior cerebral artery (ACA). Pial collaterals were defined as the sum of (A2+P2) flow. Total hemispheric flow was calculated as (M1+PCA+A2) pre-operatively and (M1+PCA+A2+Bypass) post-operatively, with the incorporation of the bypass graft.

RESULTS:

A total of 46 patients with unilateral MMD underwent revascularization with pre and post QMRA. Total intracranial flow at baseline prior to revascularization was lower in the side of disease (214.9 ml/min vs. 269.1 ml/min). Total intracranial flow at baseline after revascularization remained lower on the ipsilateral side of disease with an increased flow in the contralateral healthy side (211.7 ml/min vs 286.1 ml/min). Pre-bypass there was a higher flow through pial collaterals on the ipsilateral diseased side (183 ml/min) than the contralateral healthy side (135 ml/min). Post-bypass this difference in pial flow between ipsilateral and contralateral sides decreased from 48 ml/min to 22 ml/min (p = 0.02). Collateral ratio decreased significantly (0.46 preoperatively vs. 0.18 postoperatively) (P < 0.01).

CONCLUSIONS:

The results of this study quantitatively confirm that direct cerebral revascularization decreases collateral stress in patients with moyamoya disease.
408 Nerve to Subclavius for Neurotization Procedures: An Anatomical Feasibility Study
Authors: Cardona Juan J. , McCarty Patrick John , Chaiyamoon Arada , Carrera Ana , Reina Francisco , Georgiev Georgi P. , Iwanaga Joe , Dumont Aaron S. , Tubbs R. Shane
Published: March 2024

INTRODUCTION:

Injuries to the inferior trunk (IT) of the brachial plexus and its components can be debilitating. As such injuries are prioritized by surgeons during repair, an additional nerve transfer is considered.

METHODS:

13 adult cadavers (26 sides) underwent dissection of the nerve to subclavius and proximal brachial plexus. Once the nerve was isolated from origin to termination, the C8 and T1 roots and IT were identified. The distal end of the nerve to subclavius was transected and swung to these roots and the IT. Once the nerves to subclavius were transposed and in a tension-free manner, the length of excess nerve following being brought to each of these nerves was measured.

RESULTS:

A nerve to subclavius originated from the superior trunk and traveled anterior to the middle and inferior trunks on all sides. The mean diameter of the nerve to subclavius was 0.8 mm and the mean length was 57 mm. After cutting the nerve to subclavius at its entrance into the subclavius muscle, the distal nerve could be transferred tension free to the IT of the brachial plexus and T1 ventral ramus on all sides. The distal nerve to subclavius reached the T1 ventral ramus with an average of 18 mm of additional length and to the C8 ventral ramus with an average of 19 mm. The nerve also could be transferred to the IT of the brachial plexus with an average of 20 mm of additional length. The nerve to subclavius was found to have approximately 3,000 axons.

CONCLUSIONS:

To our knowledge, use of the nerve to subclavius has previously not been used for nerve transfer procedures. Based on our cadaveric study, this often-overlooked nerve can be easily transposed to other regional nerves such as the IT of the brachial plexus.
441 Glasgow Coma Scale Motor Score Predicts Need for Tracheostomy After Decompressive Craniectomy for Traumatic Brain Injury
Authors: Guillotte Andrew , Fry Lane , Gattozzi Domenico A. , Shah Kushal
Published: March 2024

INTRODUCTION:

Traumatic brain injury (TBI) is a common problem worldwide. Severe TBI is sometimes treated with decompressive craniectomy. Many patients who survive require tracheostomy. The decision to proceed with tracheostomy and at what time is often ambiguous. Existing methods for predicting which patients with neurologic insult will require tracheostomy are aimed at stroke and spontaneous intracranial hemorrhage (ICH).

METHODS:

We performed a retrospective review of adult patients who underwent decompressive craniectomy for severe TBI at the University of Kansas Medical Center between 2007 and 2020.

RESULTS:

100% of patients who have GCS motor score of 4 or less on POD 5 required tracheostomy. 80% of patients with GCS motor score of 5 on POD 5 required tracheostomy. Setting the threshold at GCS motor score of 5 on POD 5 for recommending proceeding with tracheostomy results in 86.7% sensitivity, 91.7% specificity, and 90.5% PPV with area under the receiver operator curve of 0.9101.

CONCLUSIONS:

GCS motor score of 5 or less on POD 5 from decompressive craniectomy for TBI is predictive of need for tracheostomy.
447 Is Surgical Management of Brachial Plexus Schwannomas Safe and Effective: A Review of Clinical Experience
Authors: Al-Mistarehi Abdel-Hameed , Menta Arjun , Hersh Andrew , Ochuba Arinze , Blakeley Jaishri , MacLean Luke , Theodore Nicholas , Belzberg Allan J. , Lubelski Daniel
Published: March 2024

INTRODUCTION:

Tumors of the brachial plexus represent a challenge because of the plexus neuroanatomical complexity and the scarce literature on the management of such rare tumors. One of these tumors is schwannomas which arise from the nerve sheath.

METHODS:

The medical records of 213 patients diagnosed with schwannomas between July 2003 and February 2020 at Johns Hopkins Medical Institutes were reviewed. The patients who had surgery for brachial plexus schwannomas were identified. Their demographic characteristics, clinical presentations, and surgical outcomes were described.

RESULTS:

Of 29 patients with brachial plexus schwannoma, 26 had surgical resection and were included in this study [Mean ± SD age, 45.00 ± 16.87 (range, 18-77); Women, 16 (61.5%)]. The most common presenting symptoms were pain (19, 73.1%) and palpable mass (18, 69.2%). Sensory and motor deficits were reported in 19 (73.1%) and 11 (42.3%) patients, respectively. The mean ± SD duration of symptoms was 20.34 ± 21.04 months, and the tumor was discovered as an incidental finding in 7 (26.9%) patients. The gross total resection was achieved in 20 (76.9%) patients. During their hospitalization for a mean of 1.58 ± 1.14 (range, 1-6) days, one patient developed postoperative wound infection, with no recorded deaths. Postoperatively, the mean follow-up duration was 17.04 ± 23.78 months. After follow-up, 12 patients reported improvements in their preoperative pains, with a recovery rate of 63.2%. Among those with preoperative neurological deficits, complete recovery from sensory and motor deficits was documented in 10 (52.6%) and 8 (72.7%) patients, respectively. However, a total of 6 patients developed new sensory and/or motor deficits. Tumor recurrence was reported in two (6.9%) patients.

CONCLUSIONS:

Brachial plexus schwannomas are surgically curable lesions by gross total resection with favorable outcomes, acceptable risks, and low incidence of tumor recurrence.
452 Leg Flexion to Overcome Gaps for Direct Sciatic Nerve Repair: An Anatomic Study
Authors: Thum Jasmine A. , Luk Justin , Brown Justin M.
Published: March 2024

INTRODUCTION:

Direct nerve repairs fare better than grafted nerves, especially for large caliber nerves. Numerous surgical techniques are used to achieve tension-free end-to-end repairs for large gaps in the sciatic nerve (SN) and common peroneal nerve (CPN), including distal nerve mobilization, transposition, side-branch neurectomy, or even shortening of the femur with distraction osteogenesis. However, leg flexion with serial distraction is the simplest, least morbid, and most easily implemented technique.

METHODS:

Eight fresh cadavers with pelvis intact were dissected to determine the relationship between degrees of knee flexion (ranged from 0 to 90-degree flexion) and the gap length overcome with nerve excursion. Additional excursion from SN side-branch neurectomy was also assessed.

RESULTS:

We found an approximately linear relationship between knee flexion and nerve excursion. In the mid-thigh there was 7-9 mm of SN excursion per 10 degrees of flexion, and 10-11 mm of SN excursion per 10 degrees of flexion with neurectomy. There was 11-13 mm of CPN excursion per 10 degrees of flexion in the distal half of the thigh.

CONCLUSIONS:

Knee flexion can significantly augment the ability to achieve an end-to-end repair of the SN and CPN. Simplified, each 10 degrees of knee flexion provides about 1 cm of additional length for both nerves, which is essentially constant throughout the arc of flexion. Neurectomy allows approximately 1-2 cm in total additional length at full flexion in fresh cadavers. Approximately 10 cm total excursion can be gained at 90-degree knee flexion with side-branch neurectomies. We recommend 45-90 days of progressive extension to respect the safe regeneration timing of 1-2 mm/day from a repair performed with 90-degree knee flexion.
469 Recovery Rate of Motor Function During Rehabilitation After Traumatic Cervical Spinal Cord Injury Predicts Functional Status at Years 1 and 5 After Surgery: A Multicenter, Longitudinal Cohort Study
Authors: Abraham Benjamin , Naik Anant , Falavigna Asdrubal , Harrop James S. , Zuckerman Scott L. , Arnold Paul M.
Published: March 2024

INTRODUCTION:

Traumatic spinal cord injury (SCI) is a devastating condition. Early surgical decompression and rehabilitative efforts in cervical SCI patients has been shown to improve neurological outcomes.

METHODS:

A longitudinal, retrospective cohort study was conducted from the multicenter Spinal Cord Injury Model Systems (SCIMS) database on patients with motor Functional Independence Measure (FIM) scores at admission to and discharge from rehabilitation, year 1, and year 5. Patients who underwent surgical decompression with neurological levels of injury limited to the cervical region and those with American Spinal Injury Association (ASIA) Impairment Scale (AIS) grades of A and B were included. The FIM score was utilized to calculate changes in motor FIM scores over each respective time period. Multivariate logistical regression was performed to identify longitudinal predictors associated with functional independence.

RESULTS:

A total of 351 patients met the inclusion criteria. The change in motor FIM score during the inpatient rehab period was a significant predictor of achieving FI at 1 and 5 years (year 1: aOR = 15.6, 95% CI 3.94-77.6, p < 0.0001; year 5: aOR = 28.0, 95% CI 6.13-173.6, p < 0.0001). For patients not achieving FI at year 1, the change in motor FIM score during inpatient rehab was a greater predictor of FI at year 5 (aOR = 64.7, 95% CI 5.15-1717.3, p = 0.0004).

CONCLUSIONS:

Inpatient rehabilitation efforts may lead to greater long-term functional status and carry emphasized importance for patients who do not attain functional independence by year 1.
471 Using the QOD to Identify Minimum Clinically Important Differences for Patients With Cervical Spondylotic Myelopathy
Authors: Lakomkin Nikita , Michalopoulos Giorgos , Kai-Hong Chan Andrew , Potts Eric A. , Park Paul , Foley Kevin T. , Wang Michael Y. , Knightly John J. , Sherrod Brandon , Gottfried Oren N. , Shaffrey Christopher I. , Agarwal Nitin , Goldberg Jacob , Virk Michael S. , Hussain Ibrahim , Fu Kai-Ming G. , Glassman Steven D. , Tumialan Luis Manuel , Turner Jay D. , Meyer Scott A. , Lu Daniel C. , Upadhyaya Cheerag D. , Shaffrey Mark Edwin , Coric Domagoj , Slotkin Jonathan , Chou Dean , Haid Regis W. , Asher Anthony L. , Bisson Erica Fay , Mummaneni Praveen V. , Bydon Mohamad
Published: March 2024

INTRODUCTION:

Minimum clinically important differences (MCID) for quality-adjusted life years (QALYs) and arm pain patient-reported outcome metrics (PROMs) in cervical spondylotic myelopathy (CSM) have yet to be determined, while data for myelopathy severity, impairment, and neck pain remain limited by small series and low rates of follow-up.

METHODS:

The CSM database of the QOD Study Group was utilized for this analysis. Patients were prospectively enrolled and followed for 24 months, with a follow-up rate of 85.2%. The MCIDs were computed for five standardized instruments: Neck Disability Index (NDI), five-dimension Euro-QoL (EQ-5D) in QALYs, neck and arm pain numeric rating scale (NRS), and modified Japanese Orthopedic Association score (mJOA) at both 3 and 24-month follow-up. Seven previously validated measures of MCID were compared using the area-under-the-curve (AUC). The North American Spine Society (NASS) satisfaction scale was the anchor, with scores of 1-2 meeting criteria for satisfaction.

RESULTS:

A total of 1,141 patients underwent surgery for CSM. Improvement of =30% from baseline was the optimal MCID across time points for NDI and neck/arm NRS. At 24 months, 30% improvement for these three instruments resulted in AUCs of 0.73, 0.71, and 0.67, respectively. Numeric cut-offs (0.065 at 3 months and 0.149 at 24 months) were the superior MCIDs for EQ-5D-derived QALYs. For mJOA, a severity-adjusted MCID outperformed the other methods, yielding an AUC of 0.67 at 24 months.

CONCLUSIONS:

We used the QOD dataset to define previously unknown MCIDs for several outcome measures. A =30% improvement from baseline was a consistent, high-performing MCID in NDI and arm/neck NRS. However, an absolute numeric cut-off (0.149) was the superior MCID for EQ-5D QALYs. mJOA exhibited the lowest predictive capacity for patient satisfaction.
478 Single-Neuron and Columnar Computations in the Human Prefrontal Cortex Underlying Transformations From Conscious Visual Perception to Speech Production
Authors: Munoz William , Williams Ziv
Published: March 2024

INTRODUCTION:

The basic functional unit of the mammalian neocortex is the cortical column. It consists of a vast diversity of circuit elements and interconnected layers supporting a range of computations for cognitive functions. While much progress has been made in our understanding of its functional architecture in animal models, its role in complex, uniquely human cognitive processes remain unknown.

METHODS:

We utilized a new columnar recording approach in humans participating of cognitive tasks, while undergoing awake neurosurgical procedures. The novelty of this approach hinged on utilizing state-of-the-art Neuropixels probes for our recordings, a silicon-based electrophysiology recording electrodes with high channel count and recording site density. This technology allows us to measure neural activity with single cell resolution throughout the neocortical column and its layers, and at a scale that is far beyond the capabilities of current clinically-approved devices. The participants performed a naturalistic visual priming-based sentence production task that provided them with pictorial representations of events that had to be articulated in specific form and order.

RESULTS:

We observed distinct spatiotemporal activity dynamics throughout the cortical column in the language-dominant prefrontal cortex that encoded a preparatory mode for speech generation, as well as visual perception and sentence construction processing stages during natural speech. Furthermore, we observed the emergence of this columnar activity pattern with optimal visual inspection of presented images (by high resolution eye and pupil tracking) and associated improved performance during the task.

CONCLUSIONS:

These results highlight a functional organization of the cortical column in the human prefrontal cortex subserving sensory-motor transformations for visual conscious perception and speech production, with profound implications for future brain machine interfaces that aim to restore complex human cogntive functions.
482 Identification of Candidate Neural Biomarkers of Obsessive-compulsive Symptom Intensity and Response to DBS
Authors: Provenza Nicole , Katlowitz Kalman , Rajesh Sameer Vikram , Diab Nabeel , Reyes Gabriel , Allam Anthony , Reddy Sandesh , Hinduja Saurabh , Avendano-Ortega Michelle , McKay Sarah , Giridharan Nisha , Banks Garrett P. , Shofty Ben , Storch Eric , Cohn Jeffrey , Goodman Wayne , Sheth Sameer A.
Published: March 2024

INTRODUCTION:

Despite the success of DBS for the treatment of refractory OCD, there are currently no robust neural signatures for obsessive-compulsive (OC) symptoms or initial mood and energy improvements associated with DBS. This gap may be due to limited opportunities available for conducting intracranial electrophysiological recordings during natural symptom fluctuations. Recently available DBS platforms offer a way over this hurdle, allowing for streaming of intracranial local field potentials (LFP) at home and in the clinic.

METHODS:

We conducted longitudinal intracranial recordings in 10 patients with refractory OCD implanted with recording-capable DBS devices targeted to ventral capsule/ventral striatum (VC/VS). Five of the 10 were additionally implanted with ECoG strip electrodes over the orbitofrontal cortex (OFC). We captured LFP at home during naturalistic exposures to OCD triggers and in the clinic during variations in stimulation amplitude.

RESULTS:

All 5 participants who have completed the study so far are clinical responders to DBS therapy. Using the intracranial data collected during OCD exposures, we identified low delta-band power as a candidate neural biomarker of OC symptom intensity during symptom provocations (left VC/VS: R = -0.59, p = 0.01; right VC/VS: R = -0.56, p = 0.04). Electrophysiological analysis of acute response to stimulation revealed a narrow band increase in 30 Hz power specific to lateral OFC that was associated with increased talkativeness and approach behaviors that are typical harbingers of clinical response

CONCLUSIONS:

These signals have potential utility for classification of symptom intensity and increased mood and energy to enable adaptive DBS systems for OCD. Our data suggest that the neural biomarkers of these two clinical features might be separable, thus possibly allowing for simultaneous optimization of both.
487 Cholinergic Blockade Alters Hippocampal-posterior Cingulate Cortex Synchrony During Episodic Memory Encoding
Authors: Schmitt Kelsey , Wang David , Lega Bradley Charles
Published: March 2024

INTRODUCTION:

The posterior cingulate cortex (PC) is an important region for episodic memory. Its synchrony with the hippocampus in the theta frequency, in particular, has been shown to underlie successful memory encoding. Cholinergic signaling is another important component of episodic memory, and manipulation of cholinergic signaling is often employed to better understand memory. However, the specific relationship between cholinergic signaling and hippocampal-PC synchrony has not been explored.

METHODS:

Eight patients with intracranial electrodes underwent two sessions of a free recall task, one in which they were given scopolamine and the other, saline. EEG recordings from these sessions during early and late encoding were then analyzed. The phases of high (5-9 Hz) and low (2-5 Hz) theta frequencies were calculated with hilbert transform, and synchrony was measured with phase-locking value (PLV), calculated for each electrode pair. Permutation tests were used to compare PLV between saline and scopolamine conditions for each electrode pair, producing a distribution of z-scores for each region-region connection. Electrodes were grouped into the regions anterior hippocampus (AH), posterior hippocampus(PH), and PC. The z-score distributions were compared against a distribution centered at zero with a t-test.

RESULTS:

The z-score distributions from permutation were significantly different from a null distribution for AH-PC connections in the left and right hemispheres during late encoding in high theta frequencies; AH-PH and PH-PC connections in the right hemisphere during early encoding in low theta frequencies; and PH-PC connections in the right hemisphere during late encoding in low theta frequencies.

CONCLUSIONS:

Changes in synchrony between PC, AH, and PH due to cholinergic blockade differ between low and high theta as well as early and late encoding.
488 National Trends in the Treatment of Refractory Epilepsy: A Nationwide Inpatient SampleBased Propensity Score Matching Analysis
Authors: Lee Seung J. , Ghaith Abdul Karim , El-Hajj; Marc Ghanem Victor Gabriel , Bydon Mohamad , Grewal Sanjeet Singh
Published: March 2024

INTRODUCTION:

Epilepsy is considered one of the most prevalent and severe chronic neurological disorders worldwide.

METHODS:

Using the NIS database from 2010-2020, patients with focal intractable epilepsy who underwent Laser Interstitial Thermal Therapy (LITT), open surgical resection, Vagal Nerve Stimulation (VNS), or Responsive Neuro-Stimulation (RNS) were identified. Outcomes such as discharge disposition, length of stay, complications, and mortality were analyzed. Propensity score matching was used to compare outcomes between pre-pandemic and pandemic (first peak of COVID-19) periods.

RESULTS:

A total of 33,969 focal intractable epilepsy cases were found with 3,343 patients receiving different treatment modalities including surgical resection (77.83%), VNS (8.21%), RNS (7.83%), and LITT (6.13%). Most of these patients (89.32%) were treated during the pre-COVID pandemic era (2010-2019), while a minority (10.67%) underwent treatment during the COVID pandemic (2020). Among all treated patients, 2.7% had postoperative neurologic complications and 0.3% died. After propensity-score matching, 658 patients (329 in each group) were included. During the pandemic period, 7% presented with preoperative paralysis/aphasia, and 0.6% had subarachnoid hemorrhages, which was significantly higher than the pre-pandemic rate (1.8%; p < 0.001). There were no statistical differences in neurologic complications, discharge disposition, or LOS between the pre-pandemic and pandemic periods. On the other hand, the mortality rate was slightly higher during the pandemic compared to the pre-pandemic period (N = 4; 1.2% vs. N = 1; 0.2%; p = 0.026).

CONCLUSIONS:

Our study shows an increase in the diagnosis of focal intractable epilepsy and a decrease in resections, while LITT and RNS usage is rising. Improving access to surgery and encouraging newer treatment modalities for DRE is crucial. Further research is needed to optimize patient outcomes and identify factors that influence treatment choices.
494 Evaluating ERK1 2 Phosphorylation as a Predictive Biomarker for Survival in Recurrent Glioblastoma Patients: A REMARK Criteria-guided Analysis of a Clinical Trial Cohort Treated With Intracerebral PD-1 and CTLA-4 Blockade
Authors: Arrieta Victor Andrés , Duerinck Johnny , Burdett Kirsten B. , Geens Wietse , Schwarze Julia K. , Gould Andrew , Habashy Karl , Chen Li , McCord Matthew , Horbinski Craig , Zhang Hui , Stupp Roger , Neyns Bart , Sonabend Adam M.
Published: March 2024

INTRODUCTION:

Glioblastoma patients exhibit variable clinical responses to anti-PD-1 immunotherapy. Our previous work identified ERK1/2 phosphorylation (p-ERK) in pre-treatment tumor samples as a predictive biomarker of overall survival in two independent cohorts of recurrent glioblastoma patients undergoing adjuvant anti-PD-1 therapy (Arrieta et al, Nat Cancer, 2021). This biomarker, however, has not yet been explored with alternative immune checkpoint blockade strategies nor assessed using REMARK criteria.

METHODS:

Adhering to REMARK criteria for biomarker validation, we investigated p-ERK as a predictor of survival in 24 evaluable recurrent glioblastoma patients from a clinical trial (NCT03233152; Duerinck J, et al, JITC, 2021). Patients underwent intracerebral administration of immune checkpoint inhibitors within a phase I clinical trial, receiving either ipilimumab (10 mg), or a combination of ipilimumab (5 mg) and nivolumab (10 mg), followed by postsurgical intravenous nivolumab (10 mg). We quantified p-ERK+ cell density in tumor regions and conducted a double-blinded statistical analysis of p-ERK’s association with survival outcomes, performed by an independent statistical team.

RESULTS:

Although analysis of the entire cohort revealed no statistically significant survival difference between patients with high and low p-ERK tumors (p = 0.29), a focused examination of wild-type IDH GBM patients demonstrated a significantly prolonged survival for those with high p-ERK tumors (median survival = 55.6 weeks, 95% CI 33.86-NA) compared to those with low p-ERK tumors (median OS of 30 weeks, 95% CI 16.14-NA; p = 0.036).

CONCLUSIONS:

Despite the limited sample size, this study highlights the promising predictive potential of p-ERK as a biomarker in a third independent prospective glioblastoma cohort treated with a novel immune checkpoint blockade administration approach, emphasizing the need for further investigation and validation in larger cohorts.
702 Multimodal CT Imaging of Ischemic Stroke Thrombi Identifies Scale-invariant Radiomic Features That Reflect Clot Biology
Authors: Santo Briana , Sarayi Seyyed , McCall Andrew , Monteiro Andre , Donnelly Brianna M , Baig Ammad , Siddiqui Adnan Hussain , Tutino Vincent
Published: March 2024

INTRODUCTION:

Biological interpretability of ischemic stroke clot imaging remains challenging. Paired CT/microCT imaging of ischemic stroke clots resected by thrombectomy has the potential to identify interpretable image features that are correlated among pre-treatment image modalities and post-treatment histopathology.

METHODS:

We performed multimodal CT-imaging and histology for 10 stroke clots retrieved by mechanical thrombectomy. Clots were manually segmented from co-registered, pre-treatment CTA and nCCT. For the same cases, resected clots were iodine-stained, and imaged with a ScanCo microCT-100 (4.9μm resolution). Afterwards, clots were subjected to histological processing (H&E staining) and whole slide scanned (40X). Clot radiomic features(RFs) (n = 93 per modality, 279 total) were extracted using PyRadiomics and histological composition was computed using Orbit Image Analysis. Correlation analysis was used to test associations between microCT and CTA (or nCCT) RFs as well as between RFs and histological composition. Statistical significance was considered at R = 0.65 and q < 0.05.

RESULTS:

From paired RF correlation analysis, we identified 23 scale-invariant RFs significantly correlated between microCT and CTA (18), and microCT and nCCT (5). Correlation of unpaired RFs identified 377 positively and 36 negatively correlated RFs between microCT and CTA, and 168 positively and 41 negatively correlated RFs between microCT and nCCT. Scale invariant RFs computed from CTA and nCCT demonstrated significant correlation with red blood cell and fibrin-platelet components, while microCT RFs were found to be correlated with WBC percent composition.

CONCLUSIONS:

This study is the first to complete a detailed statistical analysis of radiomic features across scale, and investigation of their relationship to histological composition. Our findings suggest that RFs from resected clot microCT can be used to identify strong and significant correlations between histology and pre-thrombectomy CT, with increased biological interpretability.
703 Identifying Unruptured Cavernous Internal Carotid Artery Aneurysms Growth and Rupture Over Time
Authors: Jha Rohan , Zhao Maryann , Ghannam Jack , Chalif Joshua , Altshuler Marcelle , Du Rose
Published: March 2024

INTRODUCTION:

Aneurysms in the Cavernous Segment of the Internal Carotid Artery (ICA) often present in an indolent fashion with limited morbidity. However, their growth progression and possible rupture over time remains poorly defined, thereby limiting optimization of serial follow-up.

METHODS:

We identified a retrospective cohort of 179 patients with cavernous ICA aneurysms. Patient demographic data, possible risk factors, presenting symptoms, radiographic features of aneurysms, size progression, rupture status, and concomitant non-cavernous aneurysm rupture data were manually extracted.

RESULTS:

179 patients (mean age at diagnosis 57.2 ± 15.9 years; 86.0% Female) had total 198 cavernous aneurysms. 44.4% of patients had no concomitant non-cavernous aneurysms, 41.9% had 1, and 13.6% had 2. No cavernous aneurysms ruptured during clinical follow-up. 17 non-cavernous concomitant aneurysm ruptured during follow up. 91.5% of cavernous aneurysms showed no change in size, 4.2% increased in size, and 4.2% were initially treated at time of diagnosis. Of the cavernous aneurysms that increased in size, there was a mean increase of 0.97 ± 0.4 mm and 1.1 mm ± 0.7 mm in long and short axis diameter across 5.2 ± 2.3 years. Weakness as a presenting symptom was the only predictor of cavernous aneurysm growth (p-value 0.022). Number of concomitant non-cavernous aneurysms (p-value 0.007) and sub-arachnoid hemorrhage (SAH) as a presenting symptom (p-value <0.0001) were associated with concomitant non-cavernous aneurysmal rupture.

CONCLUSIONS:

Cavernous ICA aneurysms demonstrate no rupture and limited growth over years of clinical follow-up. No patient radiographic or risk factor suggests increased risk of rupture or other symptomology, thus except for select individuals with concomitant non-cavernous aneurysms and SAH on presentation, there is likely limited clinical benefits in serially following these aneurysms over time.
759 Revisiting the ETV Success Score Using Machine Learning Can We Do Better?
Authors: Adil Syed M. , Seas Andreas , Sexton Daniel , Warman Pranav , Carter Lacey , Kolls Brad , Fuller Anthony , Lad Nandan P. , Dunn Timothy , Fuchs Herbert E. , Vestal Matthew , Grant Gerald
Published: March 2024

INTRODUCTION:

The endoscopic third ventriculostomy (ETV) success score (ETVSS) is a useful decision-making heuristic when considering the probability of surgical success, defined as no repeat CSF diversion surgery needed within six months. Nonetheless, the original dataset published in 2009 was relatively small (n = 618) and logistic regression (LR) model performance modest.

METHODS:

We queried the MarketScan national database for the years 2005-2020 to identify patients <18 years of age who underwent a first-time ETV and subsequently had at least 6 months of continuous enrollment in the database. We collected data on predictors matching the original ETVSS—age, etiology of hydrocephalus, and history of any previous shunt placement. Next, we used six ML algorithms—LR, support vector classifier, random forest, k-nearest neighbors, XGBoost, and Naive Bayes—to develop predictive models. Finally, we used nested cross-validation to assess models’ comparative performances on unseen data.

RESULTS:

We identified 1698 patients that met inclusion criteria, and 1139 (67%) had successful ETVs. Performance of all models exceeded that of the original ETVSS, with the LR model still performing best with area under the receiver operating characteristic curve (AUROC) 0.90 (95% confidence interval, 0.86-0.94), sensitivity 0.79 (0.70-0.88), and specificity 0.91 (0.87-0.95) at Youden’s index. The random forest was the second-best ML algorithm following closely behind. This compares favorably to the original ETVSS with AUROC 0.80 (0.76-0.84, p < 0.01), sensitivity 0.65 (0.47-0.85, p < 0.01), and specificity 0.71 (0.65-0.75, p < 0.01).

CONCLUSIONS:

Our predictions for ETV success outperform the current gold standard. Logistic regression may still be the most interpretable and predictive algorithm; further work is underway to externally validate these models.
873 Code Brain Ultra-Early Clinical Pathway for Patient Identification and Management in Spontaneous Non-traumatic Intracranial Hemorrhage Single-Institution Study
Authors: Sivakumar Walavan , Guan Jian , Langevin Jean-Philippe , Martin Neil A. , Barkhoudarian Garni , Kelly Daniel F. , Berry John Franklin , Iyer Aditya K.
Published: March 2024

INTRODUCTION:

Spontaneous non-traumatic intracranial hemorrhage causes high morbidity and mortality. Clinical pathways for the management of acute ischemic stroke are well established but fall short in identifying intracranial hemorrhage, preventing early therapy.

METHODS:

Using Class 1 recommendations from the AHA/ASA Spontaneous Intracranial Hemorrhage Guidelines, our multi-disciplinary stroke team developed a hyper-acute clinical pathway. Once the hemorrhagic stroke patient was identified, protocolized measures were immediately initiated to lower systolic blood pressure to 140 mmHg, institute factor replacement therapies in coagulopathic patients and anti-platelet reversal when appropriate. Key performance indicators and quality metrics were established to compare post-intervention groups to the baseline cohort.

RESULTS:

Of 180 patients, 113 and 67 patients were treated pre- and post-protocol, respectively. From pre- to post-protocol, diagnosis of hemorrhagic stroke using the alert increased from 59% to 81%. Anti-hypertensive initiation within 60 minutes increased from 79.5% to 88.7%, with the average time from CT result decreasing from 32.7 to 21.7 minutes. Time to reversal agent decreased from 53 to 23 minutes for pro-coagulation agents and 106 to 55 minutes for DDAVP. Reversal agent initiation within 60 minutes of CT result increased from 66.6% to 100% for pro-coagulation agents and 28.5% to 84.6% for DDAVP.

CONCLUSIONS:

The initiation of this management protocol for hemorrhagic stroke resulted in a higher proportion of patients being rapidly identified and earlier initiation of anti-hypertensive and hemostatic therapies. These processes are the key to important interventions designed to reduce injury extension associated with intracranial hemorrhage, like “time to thrombolysis” measures for acute ischemic stroke.
Repeat Resection for Recurrent Glioblastoma in the WHO 2021 Era: A Prospective Matched Case-Control Study
Authors: Askun Melike Mut , Zengin Yagmur , Azizova Aynur , Karli-Oguz Kader , Saydam Okay , Strobel Thomas , Soylemezoglu Figen
Published: March 2024

INTRODUCTION:

The role of resection for recurrent glioblastoma remains unclear.

METHODS:

Patients who underwent repeat resection for recurrent IDH-wild-type glioblastoma were prospectively matched with 1:1 control cohort (n = 30:30). The two groups signed the consent and were matched for age, gender, comorbidities, eloquent vs. non-eloquent location, preoperative tumor volume and extent of resection in first surgery, neuropathological features as in WHO 2021 classification, time to progression, tumor volume at the time of recurrence, Park Score, ventricular wall involvement, use of steroids or multiple antiseizure medications and adjuvant therapy. Primary aim was to evaluate the overall survival in two cohorts. The secondary aim was to determine predictive factors for long term survival after repeat resection.

RESULTS:

After matching, patients had a long term follow up until death. Median overall survival times for patients who underwent repeat and one resection was 23.8 months vs 9.1 months, respectively (Log-Rank p < 0.001). Two predictive factors for long term survival after repeat resection were preoperative Karnofsky Performance Score >70 and Glasgow Coma Scale >13 (Fisher p = 0.07 and p < 0.001, respectively) while age, time to surgery, preoperative volume, extend of resection in repeat resection, location of tumor, its extension to ventricular wall, ependymal enhancement, comorbidities, tumor histological and molecular features did not correlate with postoperative survival.

CONCLUSIONS:

This is the first prospective matched case-control study revealing survival benefit of repeat resection for recurrent gliomas with long term follow up in a select group.