Measuring CSF shunt flow with MRI using flow enhancement of signal intensity (FENSI).

PURPOSE: To develop and validate a noninvasive imaging technique for accurately assessing very slow CSF flow within shunt tubes in pediatric patients with hydrocephalus, aiming to identify obstructions that might impede CSF drainage. THEORY AND METHODS: A simulation of shunt flow enhancement of signal intensity (shunt-FENSI) signal is used to establish the relationship between signal change and flow rate. The quantification of flow enhancement of signal intensity data involves normalization, curve fitting, and calibration to match simulated data. Additionally, a phase sweep method is introduced to accommodate the impact of magnetic field inhomogeneity on the flow measurement. The method is tested in flow phantoms, healthy adults, intensive care unit patients with external ventricular drains (EVD), and shunt patients. EVDs enable shunt-flow measurements to be acquired with a ground truth measure of CSF drainage. RESULTS: The flow-rate-to-signal simulation establishes signal-flow relationships and takes into account the T1 of draining fluid. The phase sweep method accurately accounts for phase accumulation due to frequency offsets at the shunt. Results in phantom and healthy human participants reveal reliable quantification of flow rates using controlled flows and agreement with the flow simulation. EVD patients display reliable measures of flow rates. Shunt patient results demonstrate feasibility of the method and consistent flow rates for functional shunts. CONCLUSION: The results demonstrate the technique's applicability, accuracy, and potential for diagnosing and noninvasively monitoring hydrocephalus. Limitations of the current approach include a high sensitivity to motion and strict requirement of imaging slice prescription.

Thoracolumbar Interfascial Plane (TLIP) block verses other paraspinal fascial plane blocks and local infiltration for enhanced pain control after spine surgery: a systematic review.

Spinal surgeries are accompanied by excessive pain due to extensive dissection and muscle retraction during the procedure. Thoracolumbar interfascial plane (TLIP) blocks for spinal surgeries are a recent addition to regional anesthesia to improve postoperative pain management. When performing a classical TLIP (cTLIP) block, anesthetics are injected between the muscle (m.) multifidus and m. longissimus. During a modified TLIP (mTLIP) block, anesthetics are injected between the m. longissimus and m. iliocostalis instead. Our systematic review provides a comprehensive evaluation of the effectiveness of TLIP blocks in improving postoperative outcomes in spinal surgery through an analysis of randomized controlled trials (RCTs).We conducted a systematic review based on the PRISMA guidelines using PubMed and Scopus databases. Inclusion criteria required studies to be RCTs in English that used TLIP blocks during spinal surgery and report both outcome measures. Outcome data includes postoperative opioid consumption and pain.A total of 17 RCTs were included. The use of a TLIP block significantly decreases postoperative opioid use and pain compared to using general anesthesia (GA) plus 0.9% saline with no increase in complications. There were mixed outcomes when compared against wound infiltration with local anesthesia. When compared with erector spinae plane blocks (ESPB), TLIP blocks often decreased analgesic use, however, this did not always translate to decreased pain. The cTLIP and mTLP block methods had comparable postoperative outcomes but the mTLIP block had a significantly higher percentage of one-time block success.The accumulation of the current literature demonstrates that TLIP blocks are superior to non-block procedures in terms of analgesia requirements and reported pain throughout the hospitalization in patients who underwent spinal surgery. The various levels of success seen with wound infiltration and ESPB could be due to the nature of the different spinal procedures. For example, studies that saw superiority with TLIP blocks included fusion surgeries which is a more invasive procedure resulting in increased postoperative pain compared to discectomies.The results of our systematic review include moderate-quality evidence that show TLIP blocks provide effective pain control after spinal surgery. Although, the application of mTLIP blocks is more successful, more studies are needed to confirm that superiority of mTLIP over cTLIP blocks. Additionally, further high-quality research is needed to verify the potential benefit of TLIP blocks as a common practice for spinal surgeries.

SCAT5 baseline values, test-retest reliability, and reliable change metrics in high school athletes.

OBJECTIVE: In the United States, more than 1 million sport-related concussions afflict children annually, with many cases undetected or unreported. The Sport Concussion Assessment Tool (SCAT) is widely used to detect concussions in high school, collegiate, and professional sports. The objective of this study was to establish baseline values for the SCAT version 5 (SCAT5) in high school athletes. METHODS: Baseline SCAT5 evaluations were conducted in students (ages 14-19 years) from 19 high schools in central Illinois who were participating in various school-sponsored sports. The SCAT5 evaluations were retrospectively extracted from the electronic medical record system for analysis. Statistical analyses included the Wilcoxon rank-sum test for continuous variables and the chi-square test for categorical variables, considering significance at p < 0.05. Test-retest reliability at < 6 months, 10-14 months, and 16-20 months was computed using intraclass correlation and Spearman's rho (ρ). Reliable change indices are provided using the Iverson formula. RESULTS: A total of 2833 unique athletes were included, and the average age was 15.5 ± 1.14 (SD) years. There were 721 female (25.5%) and 2112 male (74.5%) athletes. Students ≥ 15 years old had more prior concussions (p < 0.001), and male athletes were more frequently hospitalized for head injury (p = 0.013). Female athletes exhibited a significantly higher prevalence of mood disorders (14.7% vs 4.6%, p < 0.001), whereas attention-deficit/hyperactivity disorder was more common in male athletes (5.2% vs 13.2%, p < 0.001). Symptom number and severity were significantly greater in female athletes (3.17 ± 4.39 vs 2.08 ± 3.49, p < 0.001; 5.47 ± 9.21 vs 3.52 ± 7.26, p < 0.001, respectively), with mood-related symptoms representing the largest differences. Female athletes and students ≥ 15 years old performed better on most cognitive assessments. Female athletes and students < 15 years old performed better on the modified Balance Error Scoring System (p < 0.001). Test-retest reliability was poor to moderate for most assessment components. Reliable change index cutoff values differed slightly by sex, with female athletes often having a greater cutoff value. CONCLUSIONS: This study underscores the variability of SCAT5 baseline values influenced by age, sex, and medical history among adolescent athletes. It provides a robust dataset, delineating baseline values stratified by sex and age within this demographic. Additionally, the results provide enhanced guidance to clinicians for interpretation of change and reliability of baselines.

Neurosurgical Implant Safety in 7 T MRI: A Scoping Review.

The use of 7 Tesla (T) magnetic resonance imaging (MRI) is expanding across neurosurgical and neurologic specialties. However, few neurosurgical-related implants have been tested for safety at 7 T, limiting its use in patients with cranial fixation, shunt placements, and other implants. Implant safety can be determined via the American Society for Testing Materials International (ASTM) guidelines. To assess the current state of neurosurgical implant safety at 7 T, a systematic search was performed using PubMed, MEDLINE, Web of Knowledge, and citation matching. Studies written in English that included at least one neurosurgical implant and at least one safety outcome were included. Data were extracted for implant studied, implant composition, deflection angle, torque, temperature change, and ASTM guidelines followed. PRISMA reporting guidelines for scoping reviews were followed. Overall, 18 studies consisting of 45 unique implants were included. Implants included cranial fixation devices, aneurysm clips, spinal rods, pedicle screws, ventriculoperitoneal (VP) shunts, deep brain stimulation devices, and electroencephalogram (EEG) caps and electrodes. Cranial fixation devices, deep brain stimulation devices, spinal rods, and pedicle screws are likely 7 T MRI compatible based on outcomes reported. Aneurysm clips and EEG devices had variable safety outcomes. The VP shunts studied lost functionality after 7 T MRI exposure. We identified several implants that are likely compatible with 7 T MRI. Given the growth in 7 T imaging and expansion of the technology, neurosurgical implants should be constructed with the aforementioned considerations. Caution must be taken with all implants, especially aneurysm clips, programmable VP shunts, and EEG recording devices. It is also noteworthy that several implant testing reports did not report following ASTM standards. This scoping review seeks to concisely summarize all neurosurgical-related implants that have been tested for safety in 7 T MRI. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 2.

Efficacy of deep brain stimulation for the treatment of anorexia nervosa: a systematic review and network meta-analysis of patient-level data.

OBJECTIVE: Deep brain stimulation (DBS) has been approved as a therapy for movement disorders and obsessive-compulsive disorder. Recently, DBS has been studied in patients with anorexia nervosa (AN), which is a debilitating and life-threatening psychiatric disorder. Several stimulation locations have been tested without a clear indication of the best region. In this systematic review and network meta-analysis, the authors used patient-level data to identify stimulation targets with the greatest evidence for efficacy in increasing body mass index (BMI). METHODS: A systematic search was performed on or before August 4, 2022, using PubMed/MEDLINE, Ovid, and Scopus. Articles were included if patient-level data were presented, patients were diagnosed with AN and treated with DBS, and 6 months or more of postoperative follow-up data were reported. Quality and risk of bias were assessed with the NIH assessment tools. Patient data were collected and stratified by stimulation location. A network meta-analysis was performed. This review was written in accordance with PRISMA guidelines for systematic reviews. RESULTS: Eleven studies consisting of 36 patients were included. The mean age and BMI at the time of surgery were 38.07 (SD 11.64) years and 12.58 (SD 1.4) kg/m2, respectively. After 6 months of DBS, a significant difference in percentage change in BMI was found between the nucleus accumbens and subcallosal cingulate cortex (SCC) (SMD 0.78; 95% CI 0.10, 1.45) and between the SCC and ventral anterior limb of the internal capsule (SMD -1.51; 95% CI -2.39, -0.62). Similarly, at 9-12 months, a significant difference in percentage change in BMI was found between the SCC and ventral anterior limb of the internal capsule (SMD -1.18; 95% CI -2.21, -0.15). With hierarchical ranking, this study identified SCC as the most supported stimulation location for BMI change at 6 and 9-12 months (P-scores 0.9449 and 0.9771, respectively). CONCLUSIONS: Several DBS targets have been tested for AN, and this study identified the SCC as the most supported region for BMI change. However, further studies with blinded on/off periods are necessary to confirm this finding.

Racial and gender disparities in traumatic brain injury clinical trial enrollment.

OBJECTIVE: Despite the increasing number of women and racial/ethnic minorities sustaining traumatic brain injuries (TBIs), they are underrepresented in TBI clinical trials. This study aimed to evaluate gender and racial diversity in enrolled cohorts of TBI clinical trials to identify trends and predictors of increased disparity over time. METHODS: The authors reviewed TBI clinical trials with reported results registered on the website ClinicalTrials.gov between 2008 and 2022. The studies were assessed for the proportion of women and racial/ethnic minorities enrolled as well as their reporting of race- and gender-specific characteristics such as gender ratio (GR) and Racial Diversity Index (RDI). Further study parameters, including year and duration, phase, trial design, type of funding, and trial completion, were also included. RESULTS: One hundred thirty-five clinical trials met inclusion criteria, of which 65 and 134 reported race and gender, respectively. Twenty-five trials were found to have existing racial disparity (RDI < 1). Comparatively, industry-funded trials had a 26% greater likelihood of racial disparities (p = 0.026), whereas federally funded trials were 30% less likely to demonstrate racial disparities (p = 0.031). Sixty-six trials had gender disparities (GR < 0.4) present, with federally funded trials showing 37.1% greater rates of gender disparity (p < 0.001, adjusted OR 5.47, 95% CI 2.26-14.25). The impact of funding source on race and gender remained significant despite adjusting for other covariates in the multivariate analyses. Racial disparity was negatively correlated with trial completion rate (p < 0.001). Disparities were not found to improve over the 14-year time span. CONCLUSIONS: Racial and gender disparities in TBI clinical trial enrollment persist, and the lack of diversity may lead to biased evidence-based medicine. Efforts should be made to increase the representation of women and racial/ethnic minorities in TBI clinical trials to ensure equitable access to effective treatments for all populations.

The neurosurgeon workforce: a geographical gender-focused analysis of the trends in representation of neurosurgeons and choices in training over 70 years.

OBJECTIVE: Neurosurgeons frequently move throughout their careers, with moves driven by personal and professional factors. In this study, the authors analyzed these migration trends through a dynamic migratory map and statistical review, with a particular focus on differences in education and practice patterns between male and female neurosurgeons. METHODS: A list containing all board-certified and -affiliated US neurosurgeons practicing in 2019 was obtained from the American Association of Neurological Surgeons. The list was augmented to include demographic and location information for medical school, residency, fellowship(s), and current practice for all neurosurgeons with publicly available data. Migration heatmaps were generated, and migration patterns over 10-year intervals were plotted. A web tool was additionally created to allow for dynamic visualization of this database. RESULTS: The database included 5307 neurosurgeons with a mean age of 57.2 ± 11.3 years. The female population made up 8.93% of all neurosurgeons, and were found to be more likely to complete fellowships than their male counterparts, at 54.2% and 39.1%, respectively (p < 0.0001). A total of 39.5% of all neurosurgeons completed at least one fellowship. A large proportion of currently practicing US neurosurgeons completed medical school internationally in the 1990s. Recently, there has been a trend in neurosurgeons choosing to practice in the South, emigrating from the Northeast and the Western US Census regions. By population, the Western US region trained the fewest neurosurgeons at 1 per 115,000 residents, and the Northeastern US region trained the most at 1 per 49,000. The web tool provides a simple interface to visualize the database on a world map. CONCLUSIONS: Diversity, equity, and inclusion in neurosurgery have been a strong point of discussion in recent literature, with neurosurgeons comprising one of the most gender-disparate workforces in the US medical system. This study provides additional metrics to assess these disparities to help motivate further action toward a larger, more diverse neurosurgical community.

Deep learning identifies brain structures that predict cognition and explain heterogeneity in cognitive aging.

Specific brain structures (gray matter regions and white matter tracts) play a dominant role in determining cognitive decline and explain the heterogeneity in cognitive aging. Identification of these structures is crucial for screening of older adults at risk of cognitive decline. Using deep learning models augmented with a model-interpretation technique on data from 1432 Mayo Clinic Study of Aging participants, we identified a subset of brain structures that were most predictive of individualized cognitive trajectories and indicative of cognitively resilient vs. vulnerable individuals. Specifically, these structures explained why some participants were resilient to the deleterious effects of elevated brain amyloid and poor vascular health. Of these, medial temporal lobe and fornix, reflective of age and pathology-related degeneration, and corpus callosum, reflective of inter-hemispheric disconnection, accounted for 60% of the heterogeneity explained by the most predictive structures. Our results are valuable for identifying cognitively vulnerable individuals and for developing interventions for cognitive decline.

Evaluating robotic pedicle screw placement against conventional modalities: a systematic review and network meta-analysis.

OBJECTIVE: Several approaches have been studied for internal fixation of the spine using pedicle screws (PSs), including CT navigation, 2D and 3D fluoroscopy, freehand, and robotic assistance. Robot-assisted PS placement has been controversial because training requirements, cost, and previously unclear benefits. This meta-analysis compares screw placement accuracy, operative time, intraoperative blood loss, and overall complications of PS insertion using traditional freehand, navigated, and robot-assisted methods. METHODS: A systematic review was performed of peer-reviewed articles indexed in several databases between January 2000 and August 2021 comparing ≥ 2 PS insertion methods with ≥ 10 screws per treatment arm. Data were extracted for patient outcomes, including PS placement, misplacement, and accuracy; operative time, overall complications, intraoperative blood loss, postoperative hospital length of stay, postoperative Oswestry Disability Index (ODI) score, and postoperative visual analog scale (VAS) score for back pain. Risk of bias was assessed using the Newcastle-Ottawa score and Cochrane tool. A network meta-analysis (NMA) was performed to estimate PS placement accuracy as the primary outcome. RESULTS: Overall, 78 studies consisting of 6262 patients and > 31,909 PSs were included. NMA results showed that robot-assisted and 3D-fluoroscopy PS insertion had the greatest accuracy compared with freehand (p < 0.01 and p < 0.001, respectively), CT navigation (p = 0.02 and p = 0.04, respectively), and 2D fluoroscopy (p < 0.01 and p < 0.01, respectively). The surface under the cumulative ranking (SUCRA) curve method further demonstrated that robot-assisted PS insertion accuracy was superior (S = 0.937). Optimal screw placement was greatest in robot-assisted (S = 0.995) placement, and misplacement was greatest with freehand (S = 0.069) approaches. Robot-assisted placement was favorable for minimizing complications (S = 0.876), while freehand placement had greater odds of complication than robot-assisted (OR 2.49, p < 0.01) and CT-navigation (OR 2.15, p = 0.03) placement. CONCLUSIONS: The results of this NMA suggest that robot-assisted PS insertion has advantages, including improved accuracy, optimal placement, and minimized surgical complications, compared with other PS insertion methods. Limitations included overgeneralization of categories and time-dependent effects.

Effect of Ventral vs Dorsal Spinal Surgery on Patient-Reported Physical Functioning in Patients With Cervical Spondylotic Myelopathy: A Randomized Clinical Trial.

Importance: Cervical spondylotic myelopathy is the most common cause of spinal cord dysfunction worldwide. It remains unknown whether a ventral or dorsal surgical approach provides the best results. Objective: To determine whether a ventral surgical approach compared with a dorsal surgical approach for treatment of cervical spondylotic myelopathy improves patient-reported physical functioning at 1 year. Design, Setting, and Participants: Randomized clinical trial of patients aged 45 to 80 years with multilevel cervical spondylotic myelopathy enrolled at 15 large North American hospitals from April 1, 2014, to March 30, 2018; final follow-up was April 15, 2020. Interventions: Patients were randomized to undergo ventral surgery (n = 63) or dorsal surgery (n = 100). Ventral surgery involved anterior cervical disk removal and instrumented fusion. Dorsal surgery involved laminectomy with instrumented fusion or open-door laminoplasty. Type of dorsal surgery (fusion or laminoplasty) was at surgeon's discretion. Main Outcomes and Measures: The primary outcome was 1-year change in the Short Form 36 physical component summary (SF-36 PCS) score (range, 0 [worst] to 100 [best]; minimum clinically important difference = 5). Secondary outcomes included 1-year change in modified Japanese Orthopaedic Association scale score, complications, work status, sagittal vertical axis, health resource utilization, and 1- and 2-year changes in the Neck Disability Index and the EuroQol 5 Dimensions score. Results: Among 163 patients who were randomized (mean age, 62 years; 80 [49%] women), 155 (95%) completed the trial at 1 year (80% at 2 years). All patients had surgery, but 5 patients did not receive their allocated surgery (ventral: n = 1; dorsal: n = 4). One-year SF-36 PCS mean improvement was not significantly different between ventral surgery (5.9 points) and dorsal surgery (6.2 points) (estimated mean difference, 0.3; 95% CI, -2.6 to 3.1; P = .86). Of 7 prespecified secondary outcomes, 6 showed no significant difference. Rates of complications in the ventral and dorsal surgery groups, respectively, were 48% vs 24% (difference, 24%; 95% CI, 8.7%-38.5%; P = .002) and included dysphagia (41% vs 0%), new neurological deficit (2% vs 9%), reoperations (6% vs 4%), and readmissions within 30 days (0% vs 7%). Conclusions and Relevance: Among patients with cervical spondylotic myelopathy undergoing cervical spinal surgery, a ventral surgical approach did not significantly improve patient-reported physical functioning at 1 year compared with outcomes after a dorsal surgical approach. Trial Registration: ClinicalTrials.gov Identifier: NCT02076113.

Patient satisfaction with treatment outcomes after surgery and/or radiotherapy for spinal metastases.

BACKGROUND: Patient satisfaction is infrequently investigated despite its importance in assessing efficacy and patient comprehension. The purpose of this study was to investigate patient satisfaction with treatment outcomes after surgery and/or radiotherapy for spinal metastases and to evaluate how health-related quality of life (HRQOL) is related to patient satisfaction. METHODS: Patients with spinal metastases treated with surgery and/or radiotherapy were enrolled in a prospective, international, observational study. Demographic, histologic, treatment, and HRQOL data were collected. HRQOL was evaluated with the Numeric Rating Scale pain score, the 3-level version of the EuroQol 5-Dimension (EQ-5D-3L) instrument, and the Spine Oncology Study Group Outcomes Questionnaire (SOSGOQ2.0). Patient satisfaction was derived from the SOSGOQ2.0 at 6, 12, and 26 weeks after treatment. Patients were classified as satisfied, neutral, or dissatisfied. RESULTS: Twelve weeks after treatment, 183 of the surgically treated patients (84%) were satisfied, and only 11 (5%) were dissatisfied; in contrast, 101 of the patients treated with radiotherapy alone (77%) were satisfied, and only 7 (5%) were dissatisfied. Significant improvements in pain, physical function, mental health, social function, leg function, and EQ-5D were associated with satisfaction after surgery. Satisfaction after radiotherapy was associated with significant improvements in pain, mental health, and overall SOSGOQ2.0 scores. Dissatisfaction after treatment was associated with lower baseline values for leg strength and lower social functioning scores for surgically treated patients and with lower social functioning scores and being single for patients treated with radiotherapy. CONCLUSIONS: High levels of satisfaction with treatment outcomes are observed after surgery and/or radiotherapy for spinal metastases. Posttreatment satisfaction is associated with significant improvements in pain and different dimensions of HRQOL.

Association of neurologic deficits with surgical outcomes and health-related quality of life after treatment for metastatic epidural spinal cord compression.

BACKGROUND: A critical knowledge gap exists regarding the impact of neurologic deficits on surgical outcomes and health-related quality of life (HRQOL) for patients surgically treated for metastatic epidural spinal cord compression (MESCC). METHODS: This prospective, multicenter and international study analyzed the impact of the neurologic status on functional status, HRQOL, and postoperative survival. The collected data included the patient demographics, overall survival, American Spinal Injury Association (ASIA) impairment scale, Spinal Instability Neoplastic Score, treatment details and complications and HRQOL measures, including version 2 of the 36-Item Short Form Health Survey (SF-36v2) and version 2.0 of the Spine Oncology Study Group Outcomes Questionnaire (SOSGOQ2.0). RESULTS: A total of 239 patients surgically treated for spinal metastases were included. Six weeks after treatment, 99 of the 108 patients with a preoperative ASIA grade of E remained stable, 8 deteriorated to ASIA D, and 1 deteriorated to ASIA A. Of 55 patients with ASIA D, 27 improved to ASIA E, 27 remained stable and 1 deteriorated to ASIA C. Of 11 patients with ASIA A to C, 2 improved to ASIA E, 4 improved to ASIA D, and 5 remained stable. At the 6- and 12-week follow-up, better ASIA scores were associated with better scores on multiple SF-36v2 and SOSGOQ items. Postoperatively, patients with ASIA grades of A to D were more likely to have urinary tract infections and wound complications. Patients with a baseline ASIA grade of E or D survived significantly longer. CONCLUSIONS: Patients with neurologic deficits due to MESCC have worse HRQOL and decreased overall survival. Nevertheless, surgery can result in stabilization or improvement of neurologic function which may translate into better HRQOL. Postoperative care and follow-up are challenging for patients with neurologic deficits because they experience more complications.

Survival, local control, and health-related quality of life in patients with oligometastatic and polymetastatic spinal tumors: A multicenter, international study.

BACKGROUND: The treatment of oligometastatic (≤5 metastases) spinal disease has trended toward ablative therapies, yet to the authors' knowledge little is known regarding the prognosis of patients presenting with oligometastatic spinal disease and the value of this approach. The objective of the current study was to compare the survival and clinical outcomes of patients with cancer with oligometastatic spinal disease with those of patients with polymetastatic (>5 metastases) disease. METHODS: The current study was an international, multicenter, prospective study. Patients who were admitted to a participating spine center with a diagnosis of spinal metastases and who underwent surgical intervention and/or radiotherapy between August 2013 and May 2017 were included. Data collected included demographics, overall survival, local control, and treatment information including surgical, radiotherapy, and systemic therapy details. Health-related quality of life (HRQOL) measures included the EuroQOL 5 dimensions 3-level questionnaire (EQ-5D-3L), the 36-Item Short Form Health Survey (SF-36v2), and the Spine Oncology Study Group Outcomes Questionnaire (SOSGOQ). RESULTS: Of the 393 patients included in the current study, 215 presented with oligometastatic disease and 178 presented with polymetastatic disease. A significant survival advantage of 90.1% versus 77.3% at 3 months and 77.0% versus 65.1% at 6 months from the time of treatment was found for patients presenting with oligometastatic disease compared with those with polymetastatic disease. It is important to note that both groups experienced significant improvements in multiple HRQOL measures at 6 months after treatment, with no differences in these outcome measures noted between the 2 groups. CONCLUSIONS: The treatment of oligometastatic disease appears to offer a significant survival advantage compared with polymetastatic disease, regardless of treatment choice. HRQOL measures were found to improve in both groups, demonstrating a palliative benefit for all treated patients.

Predictive factors of survival in a surgical series of metastatic epidural spinal cord compression and complete external validation of 8 multivariate models of survival in a prospective North American multicenter study.

BACKGROUND: This study was designed to identify preoperative predictors of survival in surgically treated patients with metastatic epidural spinal cord compression (MESCC), to examine how these predictors are related to 8 prognostic models, and to perform the first full external validation of these models in accordance with the Transparent Reporting of a Multivariable Prediction Model for Individual Prognosis or Diagnosis (TRIPOD) statement. METHODS: One hundred forty-two surgically treated patients with MESCC were enrolled in a prospective, multicenter North American cohort study and were followed for 12 months or until death. Cox regression was used. Noncollinear predictors with < 10% missing data, with ≥ 10 events per stratum, and with P < .05 in a univariate analysis were tested through a backward stepwise selection. For the original and revised Tokuhashi prognostic scoring systems (PSSs), Tomita PSS, modified Bauer PSS, van der Linden PSS, Bartels model, Oswestry Spinal Risk Index, and Bollen PSS, this study examined calibration graphically, discrimination with Harrell c-statistics, and survival stratified by risk groups with the Kaplan-Meier method and log-rank test. RESULTS: The following were significant in the univariate analysis: type of primary tumor, sex, organ metastasis, body mass index, preoperative radiotherapy to MESCC, physical component (PC) of the 36-Item Short Form Health Survey, version 2 (SF-36v2), and EuroQol 5-Dimension (EQ-5D) Questionnaire. Breast, prostate and thyroid primary tumor (HR: 2.9; P =.0005), presence of organ metastasis (hazard ratio (HR): 2.0; P = .005) and SF-36v2 PC (HR: 0.95; P < .0001) were associated with survival in multivariable analysis. Predicted prognoses poorly matched observed values on calibration plots; Bartels model calibration slope was 0.45. Bollen PSS (0.61; 95% CI: 0.58-0.64) and Bartels model (0.68; 95% CI: 0.65-0.71) had the lowest and highest c-statistics, respectively. CONCLUSIONS: The primary tumor type (breast, prostate, or thyroid), an absence of organ metastasis, and a lower degree of physical disability are preoperative predictors of longer survival for surgical MESCC patients. These results are in keeping with current models. This full external validation of 8 prognostic PSSs or model of survival in surgical MESCC patients has revealed that calibration is poor, especially for long-term survivors, whereas discrimination is possibly helpful.

Psychometric evaluation and adaptation of the Spine Oncology Study Group Outcomes Questionnaire to evaluate health-related quality of life in patients with spinal metastases.

BACKGROUND: The Spine Oncology Study Group Outcomes Questionnaire (SOSGOQ) was developed as the first spine oncology-specific health-related quality of life (HRQOL) measure. This study evaluated the psychometric properties and clinical validity of the SOSGOQ in a diverse cohort of patients with spinal metastases. METHODS: An international, multicenter, prospective observational cohort study including patients with spinal metastases who underwent surgery and/or radiotherapy was conducted by the AOSpine Knowledge Forum Tumor. Demographic, tumor, and treatment data were collected. HRQOL was evaluated using the SOSGOQ and Medical Outcomes Study Questionnaire Short Form 36 Health Survey (SF-36) at baseline and fixed follow-up times. Construct validity was assessed using multitrait scaling analyses, confirmatory factor analyses, and correlation with the SF-36 and NRS pain score. Test-retest reliability was assessed in a subgroup of patients between 12 weeks after treatment and the retest 4 to 9 days later. RESULTS: A total of 238 patients were enrolled at 9 centers across North America; 153 of these patients had HRQOL data available at 12 weeks after treatment. Multitrait scaling analyses and confirmatory factor analyses resulted in a refined version of the SOSGOQ with 4 domains and 4 single items. The revised SOSGOQ (SOSGOQ2.0) demonstrated strong correlations with SF-36 and the ability to discriminate between clinically distinct patient groups. Reliability of the SOSGOQ2.0 was demonstrated to be good, with an intraclass correlation coefficient ranging from 0.58 to 0.92 for the different domains. CONCLUSIONS: The SOSGOQ2.0 is a reliable and valid measure with which to evaluate HRQOL in patients with spinal metastases. It is recommended to use the SOSGOQ2.0 together with a generic HRQOL outcome measure to comprehensively assess HRQOL and increase sensitivity and specificity. Cancer 2018;124:1828-38. © 2018 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

Introduction: the rise of the robots in spinal surgery.

In his 1920 science fiction play R.U.R., Czech writer Karel Capek introduced the word "robot" to the English language. The play tells the story of a factory that produces roboti, which are living creatures that resemble humans and have the capacity for individual thought. While at first the roboti seem content to work for their human masters, they later rebel, ultimately leading to the extinction of the human race. 1 This play and similar depictions of robots in literature and film are probably responsible for the slightly negative reputation of robots in general. Only recently has this perception changed, thanks to the advent of robots that can vacuum our houses and perform other mundane chores. Raymond Goertz, while working for the US Atomic Energy Commission, is credited with the development of the first robotic arm in 1951. 2 It was designed to handle hazardous radioactive material. Unimation Inc. developed the first industrial robot in 1961; that robot handled molten die-castings and removed the human element from these labor-intensive, often dangerous tasks. With the development of the Programmable Universal Manipulation Arm (PUMA) in 1978, the robot was sophisticated enough to be introduced to medicine. The first working definition of the word "robot" was published, fittingly, by the Robotics Institute of America in 1980: ". . . a reprogrammable, multifunctional manipulator designed to move materials, parts, tools, or specialized devices through various programmed motions for the performance of a variety of tasks." 6 In 1988, the six-degrees-of-freedom flexible arm PUMA 560 was used to guide a needle under CT guidance into the brain. 4 With the introduction of robotic arms came the ability to use them as surgical assistants. In 1998, Okada et al. described a voice-controlled robot used to hold a thoracoscope. 5 This type of robot was also used in thoracoscopic spinal surgery. The military, having a vested interest in telepresence surgery, helped fund the development of the da Vinci Surgical System that was approved for use by the FDA in 2000 and designed to facilitate complex, minimally invasive intracavitary surgeries. 7 In 2004, the FDA cleared the first commercially available positioning device for the placement of spinal instrumentation. At present, several systems are commercially available that utilize robotics for spinal operations. In a recent review, Joseph et al. evaluated the current landscape regarding safety, accuracy, and radiation exposure with the use of these technologies. These authors concluded that "… the placement of pedicle screws with robotics appears to be safe, and accuracy appears to be superior to freehand placement, although the data are not conclusive." 3 There seems to be a significant level of interest in this technology; however, only time will tell if it will become commonplace in our field. In this issue of Neurosurgical Focus, we visually explore the expanding role of robotics and image guidance in spinal surgery. New robots used for the first time and existing robots used for novel applications graphically demonstrate how our field is evolving. The days of fearing robots are behind us as members of our specialty begin to embrace the concept of automation. Thankfully, unlike Capek's rogue roboti, surgical robots rising up against us and causing world destruction is unlikely!

A case series of dural venous sinus stenting in idiopathic intracranial hypertension: association of outcomes with optical coherence tomography.

Purpose/Aim: Pseudotumor cerebri or idiopathic intracranial hypertension (IIH) is characterized by increased intracranial pressure of unknown etiology. A subset of patients has shown benefit from endovascular dural venous sinus stenting (DVSS). We sought to identify a population of IIH patients who underwent DVSS to assess outcomes. MATERIALS AND METHODS: A retrospective study was performed to identify IIH patients with dural sinus stenosis treated with DVSS. Outcome measures included dural sinus pressure gradients, peripapillary retinal nerve fiber layer (RNFL) thickness using optical coherence tomography and improvement in symptoms. RESULTS: Seventeen patients underwent DVSS. Average pre- and post-intervention pressure gradients were 23.06 and 1.18 mmHg, respectively (p < 0.0001). Sixteen (94%) noted improvement in headache, fourteen (82%) had visual improvement and all (100%) patients had improved main symptom. Of 11 patients with optical coherence tomography, 8 showed decreased RNFL thickness and 3 remained stable; furthermore, these 11 patients had improved vision with improved papilledema in 8, lack of pre-existing papilledema in 2 and stable, mild edema in 1 patient. CONCLUSIONS: Our series of patients with dural sinus stenosis demonstrated improvement in vision and reduction in RNFL thickness. DVSS appears to be a useful treatment for IIH patients with dural sinus stenosis.

Does age affect surgical outcomes in patients with degenerative cervical myelopathy? Results from the prospective multicenter AOSpine International study on 479 patients.

BACKGROUND: In general, older patients with degenerative cervical myelopathy (DCM) are felt to have lower recovery potential following surgery due to increased degenerative pathology, comorbidities, reduced physiological reserves and age-related changes to the spinal cord. This study aims to determine whether age truly is an independent predictor of surgical outcome and to provide evidence to guide practice and decision-making. METHODS: A total of 479 patients with DCM were prospectively enrolled in the CSM-International study at 16 centres. Our sample was divided into a younger group (<65 years) and an elderly (≥65 years) group. A mixed model analytic approach was used to evaluate differences in the modified Japanese Orthopaedic Association (mJOA), Nurick, Short Form-36 (SF-36) and Neck Disability Index (NDI) scores between groups. We first created an unadjusted model between age and surgical outcome and then developed two adjusted models that accounted for variations in (1) baseline characteristics and (2) both baseline and surgical factors. RESULTS: Of the 479 patients, 360 (75.16%) were <65 years and 119 (24.84%) were ≥65 years. Elderly patients had a worse preoperative health status (p<0.0001) and were functionally more severe (p<0.0001). The majority of younger patients (64.96%) underwent anterior surgery, whereas the preferred approach in the elderly group was posterior (58.62%, p<0.0001). Elderly patients had a greater number of decompressed levels than younger patients (p<0.0001). At 24 months after surgery, younger patients achieved a higher postoperative mJOA (p<0.0001) and a lower Nurick score (p<0.0001) than elderly patients. After adjustments for patient and surgical characteristics, these differences in postoperative outcome scores decreased but remained significant. CONCLUSIONS: Older age is an independent predictor of functional status in patients with DCM. However, patients over 65 with DCM still achieve functionally significant improvement after surgical decompression.

Predicting the minimum clinically important difference in patients undergoing surgery for the treatment of degenerative cervical myelopathy.

OBJECTIVE The minimum clinically important difference (MCID) is defined as the minimum change in a measurement that a patient would identify as beneficial. Before undergoing surgery, patients are likely to inquire about the ultimate goals of the operation and of their chances of experiencing meaningful improvements. The objective of this study was to define significant predictors of achieving an MCID on the modified Japanese Orthopaedic Association (mJOA) scale at 2 years following surgery for the treatment of degenerative cervical myelopathy (DCM). METHODS Seven hundred fifty-seven patients were prospectively enrolled in either the AOSpine North America or International study at 26 global sites. Fourteen patients had a perfect preoperative mJOA score of 18 and were excluded from this analysis (n = 743). Data were collected for each participating subject, including demographic information, symptomatology, medical history, causative pathology, and functional impairment. Univariate log-binominal regression analyses were conducted to evaluate the association between preoperative clinical factors and achieving an MCID on the mJOA scale. Modified Poisson regression using robust error variances was used to create the final multivariate model and compute the relative risk for each predictor. RESULTS The sample consisted of 463 men (62.31%) and 280 women (37.69%), with an average age of 56.48 ± 11.85 years. At 2 years following surgery, patients exhibited a mean change in functional status of 2.71 ± 2.89 points on the mJOA scale. Of the 687 patients with available follow-up data, 481 (70.01%) exhibited meaningful gains on the mJOA scale, whereas 206 (29.98%) failed to achieve an MCID. Based on univariate analysis, significant predictors of achieving the MCID on the mJOA scale were younger age; female sex; shorter duration of symptoms; nonsmoking status; a lower comorbidity score and absence of cardiovascular disease; and absence of upgoing plantar responses, lower-limb spasticity, and broad-based unstable gait. The final model included age (relative risk [RR] 0.924, p < 0.0001), smoking status (RR 0.837, p = 0.0043), broad-based unstable gait (RR 0.869, p = 0.0036), and duration of symptoms (RR 0.943, p = 0.0003). CONCLUSIONS In this large multinational prospective cohort, 70% of patients treated surgically for DCM exhibited a meaningful functional gain on the mJOA scale. The key predictors of achieving an MCID on the mJOA scale were younger age, shorter duration of symptoms, nonsmoking status, and lack of significant gait impairment.