bluuebunny/crossref_metadata_2025_split huggingface dataset:
170 Towards Global Availability of Patient-Specific Cranial Implants: Creation and Validation of CranialRebuild Freeware Application
Authors: Forbes Jonathan Andrew , Xu Alice , Alfawares Yara , Ghalsasi Omkar , Venugopal Vysakh , Aryal Manish , McConaha Matthew , Cheng Josh , Matur Abhijith V. , Yang George Liu , Ngwenya Laura Benjamin , Anand Sam 
Published: March 2023

INTRODUCTION:
Financial restrictions limit attainment of hermetically-precise, patient-specific cranial implants (PSCIs) after decompressive hemicraniectomy (DHC) in developing countries. Several authors have reported use of image-segmentation, modeling software, and 3D printers to develop low-cost alternatives for PSCIs. However, technical expertise and time requirements have prevented widespread utilization of this technique.

METHODS:
A freeware algorithm titled CranialRebuild was constructed with the following capabilities: after upload of DICOM files, the normal side is analyzed in reference to the side of DHC, a Boolean subtraction algorithm is used to obtain a virtual image of the desired implant, a two-piece virtual (.STL) model of a negative of the implant is then generated. Following construction, CranialRebuild was evaluated in four cadaveric specimens. In each specimen, a standard DHC was performed. Post-DHC CT imaging were used to obtain a virtual model of the negative of the implant, which was then printed using low-cost polylactic acid (PLA). Methylmethacrylate cement was used to generate a PSCI from the PLA mold. The PSCIs were re-implanted into cadaveric specimens. Pictures were obtained, and cosmesis was subjectively evaluated using a 5-point Likert scale.

RESULTS:
Two of the four heads received a grade of 4/5, indicating optimal cosmesis could be obtained following minimal post-processing modification. Two of the heads were graded as 3/5, indicating optimal cosmesis could be obtained following moderate post-processing modification.

CONCLUSIONS:
The CranialRebuild freeware algorithm can be used to create low-cost, hermetically-precise PSCIs at a fraction of the price of third-party vendors. This technology is expected to greatly improve accessibility of customized cranial implants worldwide.
173 The State of Neurosurgical Disparities Research: Past, Present, and Future
Authors: Pugazenthi Sangami , Barpujari Awinita , Rogers James Louis , Patel Saarang , Hardi Angela , Lee Hedwig , Strahle Jennifer 
Published: March 2023

INTRODUCTION:
Social determinants of health (SDH), which influence health care access, patient outcomes, and population-level burden of disease, contribute to health disparities experienced by marginalized patient populations.

METHODS:
Embase, Ovid-MEDLINE, Scopus, Web of Science, Cochrane Library, and ProQuest Dissertations databases were queried for original research on health disparities regarding access to, outcomes of, or postoperative-management following neurosurgical procedures in the U.S. with at least one neurosurgical-affiliated author.

RESULTS:
Of 642 studies screened, 109 were included. Eighty-eight articles met all inclusion criteria other than having a neurosurgical-affiliated author and were excluded. Six studies were published prior to 2010 and 56 in the past 5 years with 62% utilizing national databases, 28% institutional databases, and 11% employing local/state/regional databases. Disparities analyzed were racial/ethnic (79%), economic/socioeconomic (59%), gender (19%), and disabled populations (0.9%) with 43% analyzing multiple/intersecting disparities. Common outcome measures were postoperative outcomes (59%), access to neurosurgical procedures (48%), and post-operative management (9%). Neuro-oncology was the most prevalent subspecialty evaluated (28%) followed by spine (26%), then pediatrics (14%), functional (11%), vascular (12%), general (7%), and trauma (3%). Senior authors with neurosurgical affiliations accounted for 87% of papers, 99% of whom were academically affiliated, and were most located in the South (29%), followed by the Northeast (28%), West (27%), and Midwest (15%).

CONCLUSIONS:
The majority of studies used national databases, assessed racial/ethnic disparities, and focused on postoperative outcomes. Many articles did not have a neurosurgery-affiliated author and the subspecialties of pediatrics, functional, vascular, and trauma were relatively underrepresented. Future research regarding SDH for neurosurgical patients will be crucial to increase healthcare access, improve outcomes, and achieve equity for marginalized patient populations. Moreover, it will be crucial for neurosurgery-affiliated researchers to engage in SDH research to increase visibility and impact of this area in neurosurgery.
180 FDA Trial of Decompression and Dynamic Sagittal Tether for Degenerative Spondylolisthesis: 24-Months Clinical and Radiographic Follow-Up
Authors: Kim Kee Duk , Sasso FAANS; Rick , Hu Serena , Bae Hyun , Villavicencio Alan T. , Lavelle William F. , Yoon Tim , Sandhu Harvinder S. , Perez-Cruet Mick J. , Bains FAANS; Ravi , Kuo Calvin , Stauff Michael , Gum Jeffrey Lynn , Deutsch Harel , Mermer Matthew , Crandall Dennis Grant , Fischgrund Jeffrey S. , Sethi Khalid Ahmed , Ray Wilson Zachary , Davis Reginald J. , Yu Elizabeth , Wang Michael Y. , Berven Sigurd , Chapman Jens , Guyer Richard D. , Shimer Adam , White Andrew Patrick , Fielding Louis , Alamin Todd , Carragee Eugene , Welch William Charles 
Published: March 2023

INTRODUCTION:
Degenerative spondylolisthesis (DS) with lumbar spinal stenosis (LSS) is commonly treated with decompression and fusion. The LimiFlex Dynamic Sagittal Tether (DST) is an investigational stabilization device for patients with DS and LSS.

METHODS:
Patients with single-level Grade 1 DS with LSS were enrolled in FDA-IDE study (NCT03115983) comparing decompression with DST and decompression with TLIF. Clinical and radiographic outcomes were assessed at baseline through 24mo postop. All propensity score (PS) selected patients who had 24mo follow-up were included in this interim analysis.

RESULTS:
At 24 mo, 224 PS-selected patients (125DST/99TLIF) had clinical follow-up. Mean characteristics of DST/TLIF groups were: age 65.8/64.1 yrs; BMI 28.1/30.0; CCI 2.5/2.4; and 57.9%/70.1% female. Mean perioperative outcomes for DST/TLIF were: procedure time 112/187 min; EBL 52/240mL; LOS 0.6/2.9 d. Mean improvements at 24mo for the DST/TLIF groups were -58.0/-57.5 mm VAS-leg/hip, -48.3/-42.2 VAS-back and -40.0/-33.4 ODI with 91%/83% achieving 15pt ODI improvement. Within 24 months, 6.5% of DST and 7.6% of TLIF patients had additional surgery at the index or adjacent level. Radiographically, at 24mo, mean reductions for the DST/TLIF groups were -1.7°/-3.7° in flexion/extension ROM and -0.4 mm/-1.0 mm in dynamic translation. At baseline/24mo, the index segment accounted for 30%/27% of index+adjacent segments ROM in the DST group and 29%/12% in the TLIF group.

CONCLUSIONS:
These results suggest that decompression+DST stabilization for DS can achieve significant clinical improvement like fusion, without an increase in reoperations within 24 mo. Imaging demonstrated no increased instability in the DST group with maintained distribution of motion between the index+adjacent segments. Further follow-up should include PS-adjusted analysis of the study composite clinical success and longer follow-up to demonstrate clinical durability of this treatment.
186 A Multi-Center, Randomized, Placebo-Controlled, Double-Blinded Trial of Efficacy and Safety of Riluzole in Acute Spinal Cord Injury Study (RISCIS)
Authors: Fehlings Michael G. , Moghaddamjou Ali , Harrop James S. , Stanford Ralph , Ball Jonathan , Aarabi Bizhan , Freeman Brian , Guest James D. , Kurpad Shekar N. , Schuster James M. , Nassr Ahmad , Schmitt Karl M. , Wilson Jefferson R. , Brodke Darrel S. , Ahmad Faiz U. , Yee Albert , Ray Zack , Brooks Nathaniel P. , Wilson Jason , Kopjar Branko , Arnold Paul M. 
Published: March 2023

INTRODUCTION:
Riluzole, a sodium-glutamate antagonist which is FDA approved for ALS has shown promising pre-clinical results and is clinically safe in SCI patients.

METHODS:
The RISCIS trial is an international, multi-center, prospective, double-blinded, randomized, placebo-controlled Phase II/III trial. Patients with ASIA A-C, C4-C8 SCI and <12 hours from injury were randomized between Riluzole, at an oral dose of 100mg BID for the first 24 hours followed by 50mg BID for the following 13 days, and placebo control.

RESULTS:
Due to the impact of the global COVID-19 pandemic this trial was terminated prior to completion. 193 patients were randomized with a follow-up rate of 82.7% at 180-days. No statistical difference was noted in the demographics and baseline injury characteristics between the two groups. At 6 months there was a median gain in total motor scores (TOTM) of 30.0 in the Riluzole group compared to 20.0 for the Placebo group. The improved motor outcomes did not reach statistical significance. Given the decreased sample size, additional sensitivity analyses were conducted. In the ASIA-C population, Riluzole was a significant improver of total motor scores (coefficient estimate: 14.10, p = 0.020) and upper motor scores (CE: 7.68, p = 0.040) at 6 months. ASIA B patients had higher reported independence, as measured by the SCIM score (45.3 vs. 27.3; p = 0.071) and change in mental health scores as measured by the SF-36 mental health domain (2.01 vs. -11.58; p: 0.0205) at 180 days.

CONCLUSIONS:
Despite the premature termination of the RISCIS trial due to the COVID-19 pandemic, 193 subjects were recruited into this trial. Primary analysis showed a 10-motor point gain in riluzole-treated subjects which did not reach significance. However, on secondary analysis, incomplete cervical SCI subjects (AIS B and C) showed significant gains in functional recovery.
193 Expansile Duraplasty Improves Motor Outcomes After Acute Traumatic Spinal Cord Injury
Authors: Greil Madeline , Robinson Emily , Saigal Rajiv 
Published: March 2023

INTRODUCTION:
Traumatic spinal cord injury (SCI) can lead to debilitating motor weakness. Early surgical decompression and optimization of spinal cord perfusion have emerged as potential therapies to prevent secondary injury caused by edema, ischemia, and inflammation. Expansile duraplasty extends decompression to the intrathecal space to optimize spinal cord perfusion. There remains a paucity of data on whether this provides a clinical benefit.

METHODS:
We included patients who underwent decompression and stabilization surgery for traumatic SCI from February 2017 to June 2021 at our level 1 trauma center. In duraplasty patients, a 1.5cm x3.5cm acellular, expansile patch was sutured into the dura at the injury site. We collected demographics, injury type, surgery performed, and American Spinal Injury Association (ASIA) motor scores (range 0-100) pre-operatively and at the time of hospital and inpatient rehabilitation discharge.

RESULTS:
101 patients were included: 12 treated with expansile duraplasty and 89 without duraplasty. The mean pre-operative motor score was 48.7 ± 29.3 for all patients, 50.5 ± 19.7 for non-duraplasty and 35.7 ± 23.0 for expansile duraplasty (p = 0.06). At rehabilitation discharge, mean change in motor score from pre-operative exam was significantly higher in duraplasty patients (19.9 ± 11.0 for duraplasty vs. 10.9 ± 13.4 for non-duraplasty, p = 0.02). There were no wound complications in the duraplasty group.

CONCLUSIONS:
In this single-center, retrospective study, SCI patients undergoing expansile duraplasty had significantly greater improvement in ASIA motor scores at rehabilitation discharge compared to non-duraplasty controls. There was no increase in wound complications nor CNS infection. These data present an independent validation of preliminary data from international centers in favor of expansile duraplasty. Further prospective studies are warranted to assess whether this technique is efficacious in treating acute traumatic SCI.
194 Intraoperative Neurophysiology Clues to Predict Success from Selective Dorsal Rhizotomy for Spastic Diplegic and Hemiplegic Cerebral Palsy
Authors: Busse Shaye , Gegg Christopher 
Published: March 2023

INTRODUCTION:
Selective dorsal rhizotomy (SDR) involves differential lesioning of divided sensory rootlets at the L1-S1 spinal levels based on interpretations of intraoperative neurophysiologic recordings. It has been shown to improve spasticity related to Cerebral Palsy, but the relationship of specific intraoperative neurophysiology measurements with clinic findings and improvements from surgery has not been investigated.

METHODS:
We performed a retrospective chart review of 39 consecutive SDRs on pediatric patients with spastic diplegia and hemiplegia, recording preoperative and postoperative toeing, scissoring, crouching, ability to walk, intraoperative stimulation frequencies, the spread of activated muscles, and whether a rootlet was lesioned. Improvement in clinical findings was analyzed as the correlate of surgical success.

RESULTS:
There was greater improvement in walking ability with more rootlets having a contralateral spread (p = .009), when more of the lesioned rootlets had contralateral spread (p = .005), and when some rootlets with contralateral spread were spared (p = .001). Among patients with preoperative toeing, there was more muscle activation intraoperatively (p < .001), greater improvement in walking ability (p < .001), and greater improvement of toeing when a lower percentage of rootlets were lesioned intraoperatively (p = .033). Among patients with preoperative crouching, there was greater improvement in crouching with smaller differences in stimulation frequency threshold between the motor and sensory roots (p = .041) and when some rootlets with contralateral spread were spared (p = .028).

CONCLUSIONS:
There is a correlation between preoperative clinical findings, intraoperative neurophysiology measurements, and postoperative clinical findings. These allow for the prediction of intraoperative recordings based on preoperative presentation. We have shown that success from SDR can be predicted using specific intraoperative measurements.
198 Endoscope-Assisted Suturectomy for Metopic Synostosis: 15-year Experience at Boston Children’s Hospital
Authors: Hori Yusuke , Albanese John , Staffa Steven , Piwowarczyk Paulina , Northam Weston , Proctor Mark R. 
Published: March 2023

INTRODUCTION:
Metopic synostosis is a subtype of craniosynostosis characterized by trigonocephaly. Endoscope-assisted suturectomy has shown its relevance as an alternative option with a lower rate of transfusion, short hospital length of stay (LOS) while maintaining comparable cosmetic outcome when compared with open repair. However, no previous reports have shown the long-term results of this procedure and factors associated with outcome.

METHODS:
133 pediatric patients with metopic synostosis treated with endoscope-assisted suturectomy between 2006 and 2021were retrospectively reviewed. Peri- and post-operative variables were extensively collected. LOS and the length of helmet therapy were defined as primary outcome. Logistic regression or median regression analysis was conducted for multivariable analysis to identify factors associated with longer LOS and length of helmet therapy. P<0.05 was defined as statistically significant.

RESULTS:
Median age was 93-days, median weight was 5.8 kg and median cranial index 0.82. Eighty-two percent of patients were male. Median surgical time was 48 minutes and estimated blood loss was 40 mL. 10 patients (7.5%) received intra- or post-op transfusion. Median pre-op Hb level was 10.1 g/dL with immediate postop level of 7.4 g/dL. Median hospital LOS was 1 day. The median length of helmet therapy was 6 months. Only one patient required minor correctional surgery for recurrence in long-term. In multivariable analysis, larger number of the pain medications administered within 24 hours after the operation (OR 1.79; P<0.001) and lower weight (OR 2.33 per kg lower; P=0.024) were significantly associated with longer LOS. Larger pre-op cranial index (OR 11.8; P=0.022) was significantly associated with longer length of helmet therapy.

CONCLUSIONS:
Our comprehensive study demonstrates that endoscope-assisted suturectomy is a safe and effective treatment for metopic synostosis and novel predictive factors associated with outcomes.
204 Radiation Exposure May Increase Risk of Malignant Peripheral Nerve Sheath Tumors in Neurofibromatosis: A Propensity-Matched Population-Level Analysis
Authors: Bhanja Debarati , Caldwell Catherine , Patel Neel T. , Sciscent Bao Y. , Freedman Zachary , Nwaneri Nkemjika , Rizk Elias Boulos 
Published: March 2023

INTRODUCTION:
Neurofibromatosis type 1 (NF1) is a hereditary condition characterized by growth of neurofibromas, which can transform into aggressive malignant peripheral nerve sheath tumors (MPNSTs). We hypothesize MPNST onset may be increasingly susceptible in the setting of prior radiation exposure in NF1 patients.

METHODS:
We performed a population-level retrospective cohort study using data collected from the TriNetX Research Network, a multi-institutional database comprising 92 healthcare organizations. Patients with NF1 were identified using ICD-10 codes. The presence or absence of radiation procedural codes prior to MPNST onset determined the radiation exposure status. NF1 patients, with and without prior radiation exposure, were propensity score matched on age, sex, and significant comorbidities. MPNST incidence and median overall survival (OS) at 1, 3, and 5 years were assessed. Kaplan Meier curves were evaluated with log-rank tests and Cox Proportional-Hazards models.

RESULTS:
A total of 35,378 NF1 patients, including 884 radiation-exposed and 34,494 radiation-naive were identified. The incidence of MPNST was 24.55% in the radiation-exposed cohort compared to 1.00% in the radiation-naive cohort. Significant risk of MPNST onset was demonstrated in the setting of prior radiation history (Risk ratio, 19.64 [95% CI 10.79-35.73], p < 0.0001). After matching, rates of OS at 5 years were 43.89% and 71.73% for NF1 patients with and without radiation, respectively. Cox proportional hazards ratios (HR, 1.57 [95% CI, 1.04-2.42]) and log-rank tests (p = 0.031) showed significant mortality in the radiation-exposed NF1-MPNST group.

CONCLUSIONS:
Patients with NF1 who had prior radiation exposure had a significantly higher incidence of MPNST, as well as lower overall survival when compared to radiation-naive NF1 patients. This suggests that radiation in NF1 patients may be cautioned, and providers may consider different treatment paradigms in their NF1 patients to limit radiation exposure.
216 Indications and Outcome of Endoscopic Transorbital Surgery for Trigeminal Schwannoma Based on the Classification: A multicenter Study With 50 cases (Korean Society of Endoscopic Neurosurgery - 009)
Authors: Kong Doo-Sik , Hong Chang-Ki , Kim Young-Hoon , Kim Yong-Hwy 
Published: March 2023

INTRODUCTION:
Trigeminal schwannoma is a rare central nervous system tumor and involves multi-compartmental skull base. Recently, endoscopic transorbital approach (ETOA) has been emerging technique as a minimally invasive surgery.

METHODS:
Between Sep. 2016 and Feb. 2022, we performed ETOA in 50 patients with trigeminal schwannoma at four tertiary hospitals. There were 15 men and 35 women with the mean age of 46.9 years. All tumors were classified type A (mainly involving the middle cranial fossa), type B (mainly posterior cranial fossa), type C (dumbbell-shaped tumor involving middle and posterior fossa), type D (Extracranial type). Type D tumors were also classified the ophthalmic division (D1), maxillary division (D2), mandibular division (D3).

RESULTS:
In this study, overall gross or near total resection was performed in 45 of 50 patients (90.0%). Median follow-up period was 21.9 months ranging from 1 to 61.7 months. There was no regrowing or recurrence during the follow-up period. Based on the classification, there were 17 tumors with type A, 1 type B, 19 type C and 13 type D. In particular, seven tumors were belong to D1, one D2, and five D3. For type A tumors, GTR/NTR was achieved with ETOA in 16 of 17 patients (94.1%). 18 of 20 patients with type C received GTR/NTR. For type D tumors, GTR was achieved in 5 of 7 patients who underwent ETOA.

CONCLUSIONS:
This study showed that trigeminal schwannomas can be effectively treated with a minimally invasive ETOA in all types of tumor except tumors mainly involving posterior fossa (type B). Especially, trigeminal schwannoma involving orbit (D1) or infratemporal fossa (D3) can be successfully removed with ETOA alone or combined ETOA with the endoscopic endonasal approach.
303 Frameless Angiography-Based Gamma Knife Stereotactic Radiosurgery for Cerebral Arteriovenous Malformations
Authors: Al Saiegh Fadi , Liu Haisong , El Naamani Kareem , Mouchtouris Nikolaos , Chen Ching-Jen , Khanna Omaditya , Abbas Rawad , Velagapudi Lohit , Schmidt Richard , Tjoumakaris Stavropoula I. , Gooch M. Reid , Rosenwasser Robert H. , Shi Wenyin , Jabbour Pascal 
Published: March 2023

INTRODUCTION:
Traditional GammaKnife radiosurgery (GKRS) of brain arteriovenous malformations (AVMs) using digital subtraction angiography requires head immobilization using a stereotactic frame.

METHODS:
This is a retrospective review of unruptured AVM patients who underwent frameless GKRS. Thin-cut magnetic resonance imaging and 3-dimensional DSA were obtained without a stereotactic frame for all patients. The imaging studies were merged for contouring of the AVM nidus. During GKRS treatment, patients were immobilized using an individually molded thermoplastic mask.

RESULTS:
Thirty-one patients were included in the analysis. The median age is 45.0 years (IQR 28.0-55.0). The median nidus size is 3.0 cm (IQR 2.0-3.4). One patient had a Spetzler-Martin grade I, 11 had a grade II, 11 had a grade III, 6 had a grade IV, and 2 had a grade IV AVM. Eleven patients underwent pre-radiosurgical embolization, two patients had previous microsurgical resection, and one patient had prior radiosurgery. The median administered dose was 20 Gy (IQR 18.0-21.0). Twenty-three patients were treated in a single fraction, 6 in 3 fractions, and two patients received 5 fractions. All patients completed their treatment with the planned radiation dose without complications.

CONCLUSIONS:
This is the first study that integrates digital subtraction angiography in the treatment planning of brain AVMs using GKRS without utilizing a stereotactic head frame. Frameless GKRS provides numerous advantages over frame-based techniques including improved patient experience, the capability of fractionation, thus, expanding the eligibility of more AVMs for radiosurgery, while maintaining high spatial resolution of the AVM using angiography data.