bluuebunny/crossref_metadata_2025_split huggingface dataset:
344 Comparison of Magnetic Resonance Relaxometry and Apparent Diffusion Coefficient for Tissue Cell Density Quantification in Glioma Imaging: Exploratory Study via 11C-methionine PET and Validation via Stereotactic Tissue Sampling
Authors: Kinoshita Manabu , Uchikoshi Masato , Sakai Mio , Kanemura Yonehiro , Shimosegawa Eku , Nakatsuka Shin-ichi , Kishima Haruhiko , Nakanishi Katsuyuki 
Published: March 2022

INTRODUCTION:
Visualization of non-contrast-enhancing tumor lesions in glioma is one of the most crucial yet challenging issues for patients with this pathology.

METHODS:
Participants comprised of patients with low- or high-grade glioma. Correlation between T1-, T2-relaxation time, ADC, and 11C-methionine uptake as measured by positron emission tomography was investigated, followed by comparing T1-, T2-relaxation time, ADC with tumor cell density as measured by stereotactic image-guided tissue sampling. MR relaxometry was achieved by converting Magnetization Prepared Rapid Gradient Echo (MP2RAGE) images and multi-echo T2-weighted images via Bayesian inference modeling.

RESULTS:
T1-relaxation time >1850 ms but <3200 ms or T2-relaxation time >115 ms, but <225 ms under 3T were indicative of high 11C-methionine uptake. Stereotactic tissue sampling study confirmed that only the T1-relaxation time of 1850-3200 ms was significantly indicative of higher tumor cell density (p = 0.02). ADC was unable to show a significant correlation with 11C-methionine uptake or with tumor cell density. Synthetic tumor load images were successfully reconstructed using T1- and T2-relaxation mapping.

CONCLUSION:
T1-relaxation time correlated well with tumor cell density in glioma tissues, while neither T2-relaxation time nor ADC showed significant correlation. The ideal ranges for identifying high tumor load tissues was 1850-3200 ms for T1-relaxation time measured at 3 T.
345 Comparable Safety Profile Between Laser Interstitial Thermal Therapy (LITT) and Stereotactic Needle Biopsy in 30-Day and 90-Day Readmission: A National Readmissions Database Analysis
Authors: Alvi Mohammed A. , Do Truong , Howard Madeleine , Huling Jared , Palzer Elise , Chen Clark C. 
Published: March 2022

INTRODUCTION:
The procedural elements of Laser Interstitial Thermal Therapy (LITT, also known as stereotactic laser ablation (SLA)) and stereotactic needle biopsy are highly similar.

METHODS:
We queried the National Readmission Database (NRD, 2010-18) for patients who underwent elective LITT or biopsy using International Classification of Diseases 9th and 10th edition codes. Readmission was defined planned, related admissions following the index admission. Odds of 30- and 90-days readmission were calculated using multivariable logistic regression.

RESULTS:
305 LITT and 7,419 needle biopsy treated brain tumor were identified. The LITT treated patients were younger (p < 0.001), female (p=0.008), and insured privately (compared to Medicare or Medicaid, p < 0.001). In terms of cancer type, a greater proportion of LITT cohort were patients brain metastasis (relative to primary brain cancer, 38.7% vs 7.2%, p < 0.001). There was no difference in non-routine discharge (LITT: 73.8%, n = 225 discharged to home vs biopsy: 80 %, n = 5,392, p = 0.826) or in-hospital mortality (0.3%,n=1 vs 0.7%, n = 50, p = 0.715). The most common neurosurgical reasons for readmissions at 30-days included unplanned readmission for index diagnosis (LITT: 2%, n = 7 vs biopsy: 3.7%, n = 272), infection (0.6%, n = 2 vs 0.46%, n = 34), seizure (0.3%, n = 1 vs 0.74%, n = 54) and cerebrovascular complication (0.3%, n = 1 vs 1%, n = 55) . The most common reason for non-neurosurgical readmission at 30 days for biopsy treated patients was deep vein thrombosis (DVT) / pulmonary embolism (PE) (0.46%, n = 35) and for LITT treated patients was an electrolyte abnormality (0.6%, n = 2). In both univariate and multivariable analyses, the odds of 30- and 90-days overall readmission, as well as neurosurgical and non-neurosurgical readmission were comparable between LITT and biopsy.

CONCLUSION:
The NRD analysis of 30- and 90-day readmission suggest comparable safety profile between LITT and stereotactic needle biopsy as treatment for brain tumor patients.
357 Novel Osteoconductive, Bioresorbable Bone Adhesive Provides Superior Cranial Flap Fixation Strength and Reduced CSF Leak Potential in a Cadaver Model
Authors: Smith Timothy R. , Foley Kevin T. , Slotkin Jonathan , Woodard Eric J. , Lazor John B. , Boruah Sourabh , Cavaleri Christy , Brown Michael C. , McDonough Brittany , Van Citters Douglas W. ,   Brigham and Women's Hospital Study Group; Geisinger Medical Center Study Group; Semmes-Murphey Clinic Study Group
Published: March 2022

INTRODUCTION:
Plates and screws are the gold standard for cranial flap fixation. Unfortunately, hardware may be associated with loosening and migration. Osseous union of the fixated flap to the surrounding skull is typically incomplete. Furthermore, titanium plates and screws do not provide a watertight closure of the bone and cannot mitigate CSF leakage.

METHODS:
64 craniotomies were performed in 16 cadavers by a single neurosurgeon. Frontal, pterional, parietal, and parieto-occipito-temporal flaps were created in each skull. The 64 bone flaps were fixated by 16 different neurosurgeons (4 flaps/surgeon). Each flap was secured with standard cranial plates and screws, then biomechanically tested using either quasi-static compression (1mm/min) or staircase impact (up to 60J impact energy at increments of 6J) to analyze mechanical strength. Next, the plates and screws were removed and the same bone flap was secured by the same neurosurgeon using a novel bone adhesive, Tetranite®(TN). The TN-secured flaps were then biomechanically tested in similar fashion. A subset of the TN-fixated flaps was subjected to hydrostatic fluid pressure (up to 40mm Hg at steps of 5mm Hg) to determine resistance to simulated CSF leakage prior to mechanical testing.

RESULTS:
TN fixation was approximately 41 times stiffer and 48 times stronger than metal fixation under quasi-static loading (stiffness 4216±1544N/mm and peak force 5456±1920N for TN vs. 103 ±81N/mm and 113±89N for metal hardware: n=32). At an impact energy of 6J, cranial flaps fixated using metal hardware migrated to a peak deflection 13 times greater than TN-fixated specimens; the residual plastic deformation was 30 times greater (peak elastic deflection 2.94± 0.81mm and plastic deflection of 1.69±0.93mm for metal hardware vs. 0.24±0.07mm and 0.06±0.04mm for TN; n=31). Of 16 TN-fixated specimens tested hydrostatically, none leaked under pressures up to 35mmHg held for 5 secs, and only 2 specimens leaked at 40mmHg.

CONCLUSION:
TN was biomechanically superior to standard cranial hardware for flap fixation. Additionally, TN acted to prevent fluid leakage. TN holds promise for improving cranial bone flap fixation biomechanically, cosmetically, and hydrostatically.
443 Intrathecal Fentanyl With a Myofascial Plane Block in Open Lumbar Surgeries
Authors: Metcalf Tyler , Sielatycki John A. , Schatzman Nathan , Devin Clinton J. , Goldstein Jeffrey A. , Hodges Scott 
Published: March 2022

INTRODUCTION:
Acute postoperative pain control following lumbar surgery is imperative to minimizing long term narcotic use and associated adverse sequela. The utility and safety of intrathecal morphine for postoperative pain management in spine surgery has been investigated; however, to date, no studies have investigated the safety of intrathecal fentanyl with a myofascial plane block in lumbar procedures.

METHODS:
An intraoperative intrathecal injection of fentanyl and a myofascial plane block was administered in 40 patients undergoing open lumbar surgery. The procedure performed was an open decompression with lumbar total joint reconstruction at one to three lumbar levels. Postoperative complications including urinary retention, respiratory depression, and need for IV opioid use were recorded.

RESULTS:
Postoperatively, zero of the study patients required IV opioid medication for supplemental pain control. Thirty-six patients (85%) were discharged same-day or prior to 23 hours postoperatively. No intrathecal fentanyl-related perioperative complications were noted. Zero of the 40 listed patients experienced urinary retention or delayed respiratory depression. One patient (2%) experienced orthostatic hypotension postoperative day one, which resolved upon discontinuation of oral oxycodone.

CONCLUSION:
Intrathecal fentanyl and myofascial plane block may be a safe option for perioperative pain control and may reduce the need for supplemental intravenous opioids without increased risk of respiratory depression, urinary retention, or other sequelae. Further studies are necessary to compare the efficacy of intrathecal fentanyl to other analgesia techniques.
802 First United States Experience with Pipeline Flex with Shield Technology for Treatment of Intracranial Aneurysms
Authors: Monteiro Andre , Cappuzzo Justin Mark , Taylor Maritza Nicole , Waqas Muhammad , Baig Ammad , Davies Jason , Snyder Kenneth Vincent , Siddiqui Adnan Hussain , Levy Elad I. 
Published: March 2022

INTRODUCTION:
Pipeline Flex with Shield technology (PED-Shield) is a third generation flow-diverter. A surface modification of the mesh with phosphorylcholine covalently bound to the metal struts aims to reduce thrombogenicity. In this study, we report the first United-States series of patients treated with the PED-Shield.

METHODS:
Information for the first 10 patients with intracranial aneurysms treated with PED-Shield was retrospectively collected. Patients were started on dual antiplatelet therapy (DAPT; 325 mg of aspirin and 75 mg of clopidogrel or 180 mg of ticagrelor) 7-days prior to intervention. After procedure, all patients were discharged on DAPT and planned to switch to aspirin alone at 6 months.

RESULTS:
Ten patients with 11 intracranial wide-necked aneurysms underwent treatment with PED-Shield between June 2021 and July 2021. The mean age of patients was 64.7 (45 - 86), and nine were female. All aneurysms were unruptured and located in the anterior-circulation. Mean maximum aneurysm diameter was 4.86mm, mean neck width was 3.05mm. Regarding morphology, all aneurysms were saccular except for one, which was fusiform. In one case, the device demonstrated insufficient distal opening, which was repaired with balloon angioplasty. There were no other technical issues or intraoperative complications. We observed no endoleak after deployment of the devices. There were two complications in the post-operative period: one patient had a groin hematoma, which was attributed to failure of the closure device and successfully managed with no clinical repercussions; one patient experienced an asymptomatic distal small intraparenchymal hematoma and trace subarachnoid hemorrhage on post-procedure non-contrast CT, which remained stable over several days. None of the patients experienced transient ischemic attacks or strokes. All patients were discharged in stable condition and unchanged functional status.

CONCLUSIONS:
In our initial experience with PED-Shield for the treatment of intracranial aneurysms, the device demonstrated excellent performance and no major complications. Further studies are needed to evaluate long term follow-up and safety of different antiplatelet regimens.
804 Should the Direct Aspiration First Pass Technique be Advocated over the StentRetriever Technique for Acute Ischemic Stroke? A Meta-analysis of 7692 patients
Authors: Ghaith Hazem , Diaa Mohamed , Negida Ahmed , Kanmounye Ulrick Sidney , Elfil Mohamed 
Published: March 2022

INTRODUCTION:
The direct aspiration first pass technique (ADAPT) was developed to achieve better recanalization in acute ischemic stroke patients. However, data from the literature are controversial regarding the comparative outcomes of this technique compared to the conventional thrombectomy by stent retriever (SR).

METHODS:
We searched PubMed, Scopus, Web of Science, and Cochrane Central Register of Controlled Trials from inception to March 2021 for relevant clinical trials and observational studies. Eligible studies were identified, and all relevant outcomes were pooled in the meta-analysis random-effects model of DerSimonian-Liard.

RESULTS:
Thirty studies were included in the meta-analysis with a total of 7868 patients. Compared with the SR, the ADAPT provides slightly higher rates of successful recanalization (RR 1.06, 95% CI [1.02 to 1.10]) and complete recanalization (RR 1.20, 95% CI [1.01 to 1.43]) but with more need for rescue therapy (RR 1.81, 95% CI [1.29 to 2.54]). There were no significant differences between the two techniques in terms of mortality at discharge, mortality at 90 days, change in the National Institutes of Health Stroke Scale (NIHSS) score, the favorable outcome (modified Rankin scale (mRS) of 0-2), time to the groin puncture, or frequency of complications as intracerebral hemorrhage (ICH), symptomatic ICH (sICH), the occurrence of an embolus in a new territory, hemorrhagic infarction, parenchymal hematoma, subarachnoid hemorrhage (SAH), and procedural complications (all P>0.05).

CONCLUSIONS:
Current evidence supports the use of the ADAPT technique to achieve successful and complete recanalization while considering the higher need for rescue therapy in some patients. Owing to its lower cost than the standard SR technique, we advocate that the ADAPT should replace the SR as the first-line thrombectomy technique in routine practice.
813 Early Surgical Decompression on Neurological Recovery in Traumatic Cervical ASIA A Spinal Cord Injury Patients
Authors: Moghaddamjou Ali , Wilson Jefferson R. , Fehlings Michael G. 
Published: March 2022

INTRODUCTION:
While there is increasing evidence for the efficacy of early surgical decompression for traumatic cervical spinal cord injury (tSCI), the impact of early surgery on motor and sensory complete (ASIA A) patients is still the subject of debate. To date, there have been no studies focusing specifically on ASIA A cervical tSCI patients.

METHODS:
Patients with cervical ASIA A injury were identified from 4 prospective, multi-center datasets (NACTN, STASCIS, NASCIS 3, and SYGEN). Patients who had a GCS <15 at baseline or were younger than 18 or older than 80 were excluded. We tabulated the number of functional motor levels gained below the neurological level of injury. A functional motor level was defined as a myotome with at least grade 3 power on the MRC scale. We defined a gain of greater than 2 functional motor levels at 1 year as a significant improvement. A-priori we isolated age, mechanism of injury, and use of steroids for multivariate analysis. Logistic regression models were used to calculate the Odds Ratio for significant improvement.

RESULTS:
We identified 365 cervical ASIA A tSCI patients with an average age of 33yrs and an average time to surgery of 168 hrs. Of those patients who had early surgery, 39.40% had a significant improvement in functional motor levels vs. 28.80% of those who did not have early surgery (P = 0.049). In Multi-variate analyses, early surgery was the only significant covariate associate with a significant impact on functional recovery (Odds Ratio of 1.65 ; p= 0.048).

CONCLUSIONS:
For the first time, we have shown a clear therapeutic benefit of early surgical decompression within 24 hrs in ASIA A tCSCI patients. These data further support the principle of early surgical intervention for all types of SCI, even those with clinically complete lesions at baseline.
816 Traveling Waves Reveal a Dynamic Source of Human Focal Seizures and Interictal Spikes
Authors: Diamond Joshua M. , Diamond Benjamin , Chapeton Julio , Inati Sarah K. , Zaghloul Kareem A. 
Published: March 2022

INTRODUCTION:
Treatment of patients with drug resistant focal epilepsy relies upon accurate seizure localization. Ictal activity captured in intracranial EEG (iEEG) has traditionally been interpreted to suggest that the underlying cortex is actively seizing. On the other hand, an emerging hypothesis suggests that seizures may in fact emerge from focal regions, which emit discharges that travel over the surface of the cortex as traveling waves.

METHODS:
20 patients underwent placement of subdural electrodes for invasive monitoring at the National Instutes of Health, underwent surgical resection for epilepsy, and had at least 1 year of follow-up. Outcomes were measured by the Engel scale. In these patients, we measured the time delay in discharge receipt at adjacent electrodes to compute the location of the seizure source. This algorithm, known as multilateration, has been used for signal source localization with sparsely-spaced sensors for over a century in geophysics, radar, and acoustics, but has not been used in epilepsy until the present.

RESULTS:
In patients with good outcome, but not in patients with poor outcome, the seizure source tends to localize to the resection territory. The source is a focal, dynamic entity that moves and evolves over the time course of a seizure. Our approach also successfully localizes interictal spikes. We find that interictal spikes emerge from multiple distinct foci in each patient. Seizures either arise from or travel to interictal spike generators.

CONCLUSIONS:
The seizure source appears to be more focal than has traditionally been conceptualized. This focal source may be localized by measuring the time difference of discharge receipt in intracranial electrodes. Algorithmic source localization, as performed here, may guide pre-surgical planning for drug-resistant epilepsy and may improve outcomes.
826 Gender Equality in Neurosurgery and Strategic Goals Towards a More Balanced Workforce
Authors: Plonsker Jillian Hannah , Benzil Deborah L. , Air Ellen L. , Woodrow Sarah , Stippler Martina , Ben-Haim Sharona 
Published: March 2022

INTRODUCTION:
The Women in Neurosurgery (WINS) published a white paper in 2008 setting a goal for women to comprise 20% of neurosurgery residents by 2012 and 20% of practicing neurosurgeons by 2020. There has been notable progress toward these benchmarks, but we ultimately fell short of their achievement.

METHODS:
A literature review was performed PubMed, Google Scholar, and published data from Accreditation Council for Graduate Medical Education (ACGME) and other society websites. to perform a thorough progress assessment. The combined expertise and experience of the authors was used to create new specific recommendations.

RESULTS:
There was an exponential increase in the number of female neurosurgical trainees in the past several decades, the percentage of female neurosurgery residents increased from 12.7% to 19.3%and the percentage of ABNS certified female neurosurgeons increased from 5% to 12% between 2010 and 2020. The total female authorship in Neurosurgery and Journal of Neurosurgery increased from 12 to 16.5% between 2003 and 2018, however there was no increase in senior authorship. Women were more likely to be published as first author with a female senior author than with a male senior author (30.4% v 14.1%). Systemic barriers identified include wage inequity of 10-25%, rampant sexual harassment, and barriers regarding parental leave policies.

CONCLUSIONS:
We propose the following updated recommendations. Neurosurgical departments and societies should make targeted effort to retain women in academic neurosurgery in order to foster mentorship opportunities. There must be explicit policies regarding sexual harassment, compensation equity, and parental leave. Finally, we propose new benchmarks of women comprising 30% of residents by 2030, and 30% of practicing neurosurgeons by 2040.
832 MR-guided Focused Ultrasound Thalamotomy of the Central Lateral Nucleus for Neuropathic Pain: An Interim and Technical Analysis
Authors: Ahmed Abdul-Kareem , Guo Sijia , Melhem Elias , Gullapalli Rao , Eisenberg Howard , Gandhi Dheeraj 
Published: March 2022

INTRODUCTION:
Neuropathic pain (NP) results from injury to the pain neuromatrix and is associated with loss of quality of life, increased health costs, and pain medication use. Thalamotomy of the central lateral nucleus (CLT) of the thalamus has demonstrated benefit in these patients.

METHODS:
Patients with 6 months or greater of symptoms and failed intervention for NP related to phantom limb pain, spinal cord injury, and spine surgery, eligible for MRgFUS treatment, were enrolled and treated with bilateral CLT. Baseline, and 1, 3, and 12 month brief pain inventory (BPI) and pain disability index (PDI) scores were collected. Treatment, radiographic, and outcome data were analyzed with t-tests and linear regression models.

RESULTS:
Eight patients (6M:2F) have been enrolled and treated to date. There have been no serious adverse events, and several patients experienced stereotactic frame-related pain which resolved. Seven tolerated bilateral CLT, one unilateral, totaling 15 ablated nuclei. Mean age was 53.9 years. By 3 months, BPI decreased by 56.3% (n=7, p=.002), PDI decreased by 41.2% (n=7, p=.016). Energy to reach 50 Celsius correlated with skull density ratio (SDR) (R2=.54 p=.038). SDR did not correlate with BPI or PDI improvement. For 15 nuclei, mean lesion volume was 150.4 mm³. Total lesion volume in each patient did not correlate with BPI or PDI improvement.

CONCLUSIONS:
MRgFUS bilateral CLT is safe for chronic NP, and has efficacy in reducing symptoms as measured by validated pain scales. As with other MRgFUS ablative interventions, SDR correlates with acoustic transmission through the skull, and lesion volume does not affect clinical outcome.
839 Techniques for Management and Avoidance of Ventriculo Artrial Shunt Distal Catheter Complications
Authors: Zervos Thomas , Kutschman Kenneth , Mansour Tarek R. , Frisoli Tiberio , Air Ellen L. , Schwalb Jason M. 
Published: March 2022

INTRODUCTION:
Minimizing the risk of distal ventriculatrial (VA) shunt disconnection is particularly important due to the risk of catheter embolization. This rare event occurs in approximately 1.56% of implanted VA shunts. There are no clear treatment guidelines in the literature to help prevent and manage this complication. The use of a connector in the neck has been implicated in mechanical failures of ventriculoperitoneal (VP) shunts;2however, to the best of our knowledge, there was no literature describing disconnection and migration of distal VA shunt catheters due to use of a connector.

METHODS:
Clinical records for a single institution between 2010 and 2021 were reviewed for instances of distal catheter disconnection and migration.

RESULTS:
All three instances of distal disconnection were associated with use of a connector in the neck that resulted in fracture of the catheter due to repetitive sheering forces. In all three cases, the distal catheter was retrieved via an endovascular approach in conjunction with transesophageal echocardiography to assess for retrieval feasibility. An additional case is included where the distal catheter is abandoned due to adhesions and the patient was placed on anticoagulation.

CONCLUSIONS:
We recommend the avoidance of a straight connector when performing VA shunt placement. Catheter removal requires a multidisciplinary approach to best reduce risk of complications.