Network Influence of the Cerebellum for Predicting DBS Response in Patients with Advanced Parkinson’s Disease

Introduction: Deep brain stimulation (DBS) is a treatment option for reducing motor symptoms in patients with Parkinson’s Disease (PD) when first-line medication becomes ineffective. Existing literature has hypothesized that the clinical outcome of DBS may depend on brain connectivity profiles of the stimulation site to distant brain regions. However, the potential of brain connectivity profiles to predict response to DBS in PD remains unclear. Objective: This study aimed to investigate how changes in structural and functional connectivity may relate to patient response to DBS, through the examination of brain network changes using graph theory. Methods: Ten patients with advanced PD were included in this study. Diffusion tensor imaging (DTI) and resting-state fMRI scans were acquired prior to DBS implantation. Pre-DBS and post-DBS UPDRS-III scores were obtained. Network analysis of the DTI and fMRI scans was performed using GRETNA to compute structural and functional graph theory metrics, respectively. Metrics were correlated with UPDRS-III improvement to identify significant correlations to UPDRS improvement due to DBS. Results: Combined structural and functional graph theory metrics highlighted 32 structures to be significantly correlated with UPDRS-III improvement. Mainly, connections to the cerebellum were found to be significantly correlated with UPDRS-III improvement across several metrics for both structural and functional connectivity. Discussion: This work combined DTI, fMRI, and graph theory analysis to evaluate improvement with DBS. Several imaging biomarkers were identified that are robust predictors for UPDRS-III improvement. This work warrants investigation into the compensatory effect of the cerebellum and other potential biomarkers for identifying DBS candidates

Characteristic Dynamic Functional Connectivity During Sevoflurane-Induced General Anesthesia

General anesthesia (GA) during surgery is commonly maintained by inhalational sevoflurane. Previous resting state functional MRI (rs-fMRI) studies have demonstrated suppressed functional connectivity (FC) of the entire brain networks, especially the default mode networks, transitioning from the awake to GA condition. However, accuracy and reliability were limited by previous administration methods (e.g. face mask) and short rs-fMRI scans. Therefore, in this study, a clinical scenario of epilepsy patients undergoing laser interstitial thermal therapy was leveraged to acquire 15 min of rs-fMRI while under general endotracheal anesthesia to maximize the accuracy of sevoflurane level. Nine recruited patients had fMRI acquired during awake and under GA, of which seven were included in both static and dynamic FC analyses. Group independent component analysis and a sliding-window method followed by k-means clustering were applied to identify four dynamic brain states, which characterized subtypes of FC patterns. Our results showed that a low-FC brain state was characteristic of the GA condition as a single featuring state during the entire rs-fMRI session; In contrast, the awake condition exhibited frequent fluctuations between three distinct brain states, one of which was a highly synchronized brain state not seen in GA. In conclusion, our study revealed remarkable dynamic connectivity changes from awake to GA condition and demonstrated the advantages of dynamic FC analysis for future studies in the assessments of the effects of GA on brain functional activities

How accurate is the neurosurgery literature? A review of references.

BACKGROUND: The reference list is an important part of academic manuscripts. The goal of this study is to evaluate the reference accuracy in the field of neurosurgery. METHODS: This study examines four major peer-reviewed neurosurgery journals, chosen based on their clinical impact factor: Neurosurgery, J Neurosurg, World Neurosurg, and Acta Neurochir. For each of the four journals, five articles from each of the journal\u27s 12 issues published in 2019 were randomly selected using an online generator. This resulted in a total of 240 articles, 60 from each journal. Additionally, from each article\u27s list of references, one reference was again randomly selected and checked for a citation or quotation error. The chi-square test was used to analyze the association between the occurrence of citation and quotation errors and the presence of hypothesized risk factors that could impact reference accuracy. RESULTS: 62.1% of articles had a minor citation error, 8.33% had a major citation error, 12.1% had a minor quotation error, and 5.8% of articles had a major quotation error. Overall, Acta Neurochir presented with the fewest quotation errors compared with the other journals evaluated. The only association between the frequency of errors and potential markers of reference mistakes was with the length of the bibliography. Surprisingly, this correlation indicated that the articles with longer reference lists had fewer citation errors (p \u3c 0.01). Statistical significance was found between the occurrence of citation errors and the journals of publication (p \u3c 0.01). CONCLUSIONS: In order to advance medical treatment and patient care in neurosurgery, detailed documentation and attention to detail are necessary. The results from this analysis illustrate that improved reference accuracy is required

Clinical Outcomes with and without Adherence to Evidence-Based Medicine Guidelines for Lumbar Degenerative Spondylolisthesis Fusion Patients

Introduction: Degenerative lumbar spondylolisthesis (DS) patients are treated with instrumented fusion, following EBM guidelines, and typically have excellent clinical outcomes. However, not all lumbar fusion procedures adhere to EBM guidelines, typically due to a lack of prospective data. Objective: This retrospective study compared outcomes of DS lumbar fusion patients treated according to EBM guidelines (EBM concordant) to lumbar fused patients with procedures that did not have clear EBM literature that supported this treatment, the goal being to examine the value of present EBM to guide clinical care. Methods: A total of 125 DS patients were considered EBM concordant, while 21 patients were EBM discordant. Pre- and postsurgical ODI scores were collected. Clinical outcomes were stratified into substantial clinical benefit (SCB ΔODI \u3e10 points), minimal clinical importance benefit (MCID ΔODI ≥ 5 points), no MCID (ΔODI \u3c 5 points), and a group that showed no change or worsening ODI. Fisher\u27s exact and χ2 tests for categorical variables, Student\u27s t-test for continuous variables, and descriptive statistics were used. Statistical tests were computed at the 95% level of confidence. Results: Analysis of 125 degenerative spondylolisthesis patients was performed comparing preoperative and postoperative (6 months) ODI scores. ODI improved by 8 points in the EBM concordant group vs. 2.1 points in the EBM discordant group (p = 0.002). Compliance with EBM guidelines was associated with an odds ratio (OR) of 2.93 for achieving MCID ([CI]: 1.12-7.58, p = 0.027). Conclusions: Patients whose lumbar fusions met EBM criteria had better self-reported outcomes at six months than those who did not meet the requirements. A greater knowledge set is needed to help further support EBM-guided patient care

The Impact of Intraoperative Image-Guidance Modalities and Neurophysiologic Monitoring in the Safety of Sacroiliac Fusions.

STUDY DESIGN: Retrospective observational cohort. OBJECTIVE: A review of efficiency and safety of fluoroscopy and stereotactic navigation system for minimally invasive (MIS) Sacroiliac (SI) fusion through a lateral technique. METHODS: Retrospective analysis of an observational cohort of 96 patients greater than 18 years old, that underwent MIS SI fusion guided by fluoroscopy or navigation between January 2013 and April 2020 with a minimum of 3 months follow-up. Intraoperative neuromonitoring (IONM) with a variable combination of electromyography (EMG), somatosensory evoked potentials (SSEPs) and motor evoked potentials (MEPs) was also utilized. RESULTS: The overall complication rate in the study was 9.4%, and there was no difference between the fluoroscopy (10.1%), and navigation groups (8%). Neurological complication rate was 2.1%, without a significant difference between both intraoperative guidance modality groups (p = 0.227). There was a significant difference between the modalities of IONM used and the occurrence of neurological injury (p = 0.01).The 2 patients who had a neurological complication postoperatively were monitored only with EMG and SSEP, but none of the patients (n = 76) in which MEPs were utilized had neurologic complication. The mean pain improvement 3 months after surgery was greater in the navigation group (2.44 ± 2.72), but was not statistically different than the improvement in the fluoroscopy group (1.90 ± 2.07) (p = 0.301). CONCLUSIONS: No difference in the safety of the procedure was found between the fluoroscopy and the stereotactic navigation techniques. The contribution of the IONM to the safety of SI fusions could not be determined, but the data indicates that MEPs provide the highest level of sensitivity

Are Guidelines Important? Results of a Prospective Quality Improvement Lumbar Fusion Project.

BACKGROUND: United States (U.S.) healthcare is a volume-based inefficient delivery system. Value requires the consideration of quality, which is lacking in most healthcare disciplines. OBJECTIVE: To assess whether patients who met specific evidence-based medicine (EBM)-based criteria preoperatively for lumbar fusion would achieve higher rates of achieving the minimal clinical important difference (MCID) than those who did not meet the EBM indications. METHODS: All elective lumbar fusion cases, March 2018 to August 2019, were prospectively evaluated and categorized based on EBM guidelines for surgical indications. The MCID was defined as a reduction of ≥5 points in Oswestry Disability Index (ODI). Multiple logistic regression identified multivariable-adjusted odds ratio of EBM concordance. RESULTS: A total of 325 lumbar fusion patients were entered with 6-mo follow-up data available for 309 patients (95%). The median preoperative ODI score was 24.4 with median 6-mo improvement of 7.0 points (P \u3c .0001). Based on ODI scores, 79.6% (246/309) improved, 3.8% (12/309) had no change, and 16% (51/309) worsened. A total of 191 patients had ODI improvement reaching the MCID. 93.2% (288/309) cases were EBM concordant, while 6.7% (21/309) were not.In multivariate analysis, EBM concordance (P = .0338), lower preoperative ODI (P \u3c .001), lower ASA (American Society of Anesthesiologists) (P = .0056), and primary surgeries (P = .0004) were significantly associated with improved functional outcome. EBM concordance conferred a 3.04 (95% CI 1.10-8.40) times greater odds of achieving MCID in ODI at 6 mo (P = .0322), adjusting for other factors. CONCLUSION: This analysis provides validation of EBM guideline criteria to establish optimal patient outcomes. The EBM concordant patients had a greater than 3 times improved outcome compared to those not meeting EBM fusion criteria

The bulbocavernosus reflex (BCR) has no prognostic features during the acute evaluation of spinal cord injuries

The bulbocavernosus reflex (BCR) has been used during the initial evaluation of a spinal cord injury patient as a metric to determine prognosis and whether the patient is in "spinal shock". This reflex has been less utilized over the last decade and therefore, a review was performed to assess the value of BCR in patient prognosis. The North American Clinical Trials Network (NACTN) for Spinal Cord Injury is a consortium of tertiary medical centers that includes a prospective SCI registry. The NACTN registry data was analyzed to evaluate the prognostic implication of the BCR during the initial evaluation of a spinal cord injury patient. SCI patients were divided into those with an intact or absent BCR during their initial evaluation. Associations of participants' descriptors and neurological status on follow up were performed followed by associations with the presence of a BCR. 769 registry patients with recorded BCRs were included in the study. The median age was 49 years (32-61 years), majority were male (n=566, 77%), and white (n=519, 73%). Among included patients, high blood pressure was the most common comorbidity (n=230, 31%). Cervical spinal cord injury was the most common (n=470, 76%) with fall (n=320, 43%) being the most frequent mechanism of injury. BCR was present in 311 patients (40.4%), while 458 (59.6%) had a negative BCR within 7 days of injury or before surgery. At 6 months post-injury, 230 patients (29.9%) followed up, of which, 145 had a positive BCR while 85 had a negative BCR, respectively. The presence/absence of BCR was significantly different in patients with cervical (p=0.0015) or thoracic SCI (p=0.0089), or conus medullaris syndrome (p=0.0035), and in those who were AIS grade A (p=0.0313). No significant relationship was observed between BCR results and demographics, AIS grade conversion, motor score changes (p=0.1669), and changes in pin prick (p=0.3795) and light touch scores (p=0.8178). In addition, cohorts were not different in surgery decision (p=0.7762) and injury to surgery time (p=0.0681). In our review of the NACTN spinal cord registry, the BCR did not provide prognostic utility in the acute evaluation of spinal cord injury patients. Therefore, it should not be used as a reliable marker for predicting neurological outcomes post-injury

Does Pre-Operative Opiate Choice Increase Risk of Post-Operative Infection and Subsequent Surgery?

BACKGROUND: Opioids are commonly prescribed for chronic pain prior to spinal surgery and research has shown an increased rate of post-operative adverse events in these patients. OBJECTIVE: This study compared the incidence of two-year subsequent surgical procedures and post-operative adverse events in patients undergoing lumbar fusion with or without 90-day pre-operative opioid use. We hypothesized that patients using preoperative opioids to have a higher incidence of subsequent surgery and adverse outcomes. METHODS: A retrospective cohort study was performed using Optum Pan-Therapeutic Electronic Health Records database including adult patients who had their first lumbar fusion between 2015 and 2018. The daily average preoperative opioid dosage 90 days prior to fusion was determined as morphine equivalent dose (MED) and further categorized into high-dose (MED\u3e100mg/day) and low-dose (1-100mg/day). Clinical outcomes were compared after adjusting for confounders. RESULTS: A total of 23,275 patients were included, with 2,112 (10%) patients using opioids preoperatively. There was a significantly higher incidence of infection compared to non-users (12.3% versus 10.1%; P=0.01). There was no association between subsequent fusion surgery (7.9% versus 7.5%, P=0.52) and subsequent decompression surgery (4.1% versus 3.6%; P=0.3) between opioid users and non-users. Regarding post-operative infection risk, low-dose users showed significantly higher incidence (12.7% versus 10.1%; P CONCLUSION: Consistent with prior publications, opioid use was significantly associated with a higher incidence of two-year post-operative infection compared to non-use. Low-dose opioid users had higher post-operative infection rates than non-users