Intraoperative language mapping guided by real-time visualization of gamma band modulation electrocorticograms: Case report and proof of concept.

Background: Electrocorticography (ECoG) language mapping is often performed extraoperatively, frequently involves offline processing, and relationships with direct cortical stimulation (DCS) remain variable. We sought to determine the feasibility and preliminary utility of an intraoperative language mapping approach guided by real-time visualization of electrocorticograms. Methods: A patient with astrocytoma underwent awake craniotomy with intraoperative language mapping, utilizing a dual iPad stimulus presentation system coupled to a real-time neural signal processing platform capable of both ECoG recording and delivery of DCS. Gamma band modulations in response to 4 language tasks at each electrode were visualized in real-time. Next, DCS was conducted for each neighboring electrode pair during language tasks. Results: All language tasks resulted in strongest heat map activation at an electrode pair in the anterior to mid superior temporal gyrus. Consistent speech arrest during DCS was observed for Object and Action naming tasks at these same electrodes, indicating good correspondence with ECoG heat map recordings. This region corresponded well with posterior language representation via preoperative functional MRI. Conclusions: Intraoperative real-time visualization of language task-based ECoG gamma band modulation is feasible and may help identify targets for DCS. If validated, this may improve the efficiency and accuracy of intraoperative language mapping.

Implementation of an Enhanced Recovery After Spine Surgery program at a large cancer center: a preliminary analysis.

This study describes the implementation of a multimodal, multidisciplinary, evidence-based ERAS program in oncologic spine surgery, identifies and measures several relevant postoperative recovery outcomes, and demonstrates the feasibility and potential benefit of the program in improving analgesia and decreasing opioid consumption. The study underscores the importance of defining and capturing meaningful, patient-specific, and patient-reported outcomes, and constant evaluation and monitoring of a group's compliance with the program. The study represents the steppingstone for evaluation and improvement of a young ERAS program for spine surgery and serves as a roadmap for further initiatives and larger-scale studies.

Scalp blocks for brain tumor craniotomies: A retrospective survival analysis of a propensity match cohort of patients.

To test the association between the use of scalp blocks for malignant brain tumor craniotomy and survival. This is a retrospective study conducted in a tertiary academic center. Demographic, intraoperative and survival data from 808 adult patients with malignant brain tumors was included in the analysis. Patients were divided in those who received an Intraoperative use of scalp block or not. The progression free survival (PFS) and overall survival (OS) rates were compared in patients who had and had not scalp blocks. Kaplan-Meier method was used for time-to-event analysis including recurrence free survival and overall survival. Multivariate analyses before and after propensity score matching were conducted to test the association between different covariates including scalp blocks with PFS and OS. Five hundred and ninety (73%) of the patients had a scalp block. Before PSM, patients with a scalp block were more likely to have an ASA physical status of 3-4, recurrent tumors and receive adjuvant radiation. Patients with scalp block showed no significant reduction in intraoperative opioids. After adjusting for significant covariates, the administration of a scalp block was not associated with an increase in PFS (HR, 95%CI = 0.98, 0.8-1.2, p = 0.892) or OS (HR, 95%CI = 1.02, 0.82-1.26, p = 0.847) survival. This retrospective study suggests that the use of scalp blocks during brain tumor surgery is not associated with patients' longer survival.

Laser interstitial thermal therapy of the spine: technical aspects.

Spinal laser interstitial thermal therapy has been developed as a minimally invasive modality to treat epidural spinal tumors percutaneously. The safe and effective use of this technology requires meticulous preoperative trajectory planning and an intraoperative workflow incorporating navigation and MR thermography. Instrumented stabilization can be performed during the same operation if needed. Operative considerations and technical aspects are reviewed. The video can be found here: https://youtu.be/P--frsag6gU .

Association between intravenous acetaminophen and reduction in intraoperative opioid consumption during transsphenoidal surgery for pituitary tumors.

BACKGROUND AND AIMS: Pain during and after transsphenoidal surgeries originates from stimulation of branches of the trigeminal cranial nerve that supply the inner aspect of the nose cavity and dura mater. Thereby, patients undergoing transsphenoidal surgery may require moderate-to-large amounts of analgesics including opioids. Intravenous acetaminophen provides analgesia and reduces opioid consumption for a wide variety of surgeries. We hypothesized that the use of intravenous acetaminophen is associated with a reduction in intraoperative opioid consumption and provides significant analgesia during and after transsphenoidal surgery. MATERIAL AND METHODS: This retrospective study included 413 patients who underwent transsphenoidal surgery for pituitary adenomas. The primary outcome of this study was intraoperative opioid consumption. Secondary outcomes included pain intensity, Richmond Agitation Sedation Scale scores, and nausea and vomiting upon arrival to postoperative anesthesia care unit. Patients were divided into two groups based on the intraoperative acetaminophen use. A prospensity score matching analysis was used to balance for important variables between the two groups of treatment. Regression models were fitted after matching the covariates. A P < 0.05 was considered statistically significant. RESULTS: After matching, 126 patients were included in each group of treatment. Patients in the acetaminophen group required significantly less amount (a decrease by 14.9%) of opioids during surgery than those in the non-acetaminophen group. Postoperative pain, postoperative nausea and vomiting, and sedation scores were not significantly different between patients who received intravenous acetaminophen and those who did not. CONCLUSION: Intravenous acetaminophen is associated with a reduction in intraoperative opioids during transsphenoidal pituitary surgery.

Association Between Perioperative Hyperglycemia and Survival in Patients With Glioblastoma.

BACKGROUND: Several studies have examined the association between hyperglycemia in the first 10 to 12 weeks following surgery and postoperative survival in glioblastoma multiforme (GBM) patients. We hypothesize that episodes of hyperglycemia before, during and/or following surgery for primary GBM are independent predictors of disease progression and mortality. MATERIALS AND METHODS: A total of 162 adult patients were included in the analysis. All patients received adjuvant temozolamide. The progression free survival (PFS) and overall survival (OS) rates at 1 and 5 years were analyzed using different glycemic cutoff values. Multivariate analyses were conducted to test the association between preoperative, intraoperative and postoperative hyperglycemia with PFS and OS. RESULTS: Kaplan-Meier curves revealed a trend toward increased PFS and OS with lower glucose concentrations with the exception of glucose concentrations >180 mg/dL in the intraoperative/postoperative day 0 time period. Univariate analysis of blood glucose levels did not demonstrate a statistically significant effect on PFS in any time period, however hyperglycemia was statistically significant for OS in the preoperative time period. Although, multivariate analysis showed no statistically significant association with hyperglycemia on PFS, a statistically significant decrease in OS was seen for plasma glucose concentrations >112 mg/dL (P=0.01) and >180 mg/dL (P=0.01) in the preoperative period. There was a decreasing effect on OS with blood glucose concentrations greater than the median in multiple time periods (P=0.02). CONCLUSIONS: Preoperative hyperglycemia is associated with poor OS after GBM surgery.

Revisiting anatomic landmarks: lateral popliteal approach for sciatic nerve block based on magnetic resonance imaging.

BACKGROUND AND OBJECTIVES: When the conventional lateral popliteal sciatic nerve (SN) block is performed, the needle angle required to localize and the level of the SN bifurcation are highly variable. The aim of our magnetic resonance imaging (MRI) study was to determine the most common range of needle-insertion angles and the relationship between skin-to-femur distance and angle. We also evaluated the variability of the SN bifurcation level and the relationship between patient height and nerve bifurcation level. METHODS: Using 289 thigh MRIs to simulate a lateral approach in the supine position, we measured and analyzed with simple linear regressions the level of SN bifurcation, the skin-to-femur and SN-to-femur distances, and the angle at which the needle must be directed posteriorly to intersect the SN at 9 cm proximal to the lateral joint line. RESULTS: The mean insertion angle was 30 (SD, 8) degrees. In 95% of cases, angles ranged from 15 to 45 degrees, and the larger the thigh, the smaller the angle. The SN divided at a mean distance of 7.5 (SD, 1.6) cm (range, 1.5-12.8 cm) proximal to the lateral joint line. In 93% of cases, the bifurcation level was 10 cm or less. CONCLUSIONS: Our simulated lateral popliteal SN block on MRIs shows a 15- to 45-degree range of needle-insertion angles. As the skin-to-femur distance was greater than 4.5 cm, the angles were progressively smaller than 30 degrees. Although this was an MRI study, it does provide some evidence that indicates the conventional clinically recommended 25- to 30-degree-angle ranges may need to be reevaluated. Needle insertion of 10 cm or greater proximal to the popliteal crease may increase the chance of placement at or proximal to the SN bifurcation.

pH Heterogeneity of human and rabbit atherosclerotic plaques; a new insight into detection of vulnerable plaque.

BACKGROUND: Atherosclerotic plaques are heterogeneous with respect to inflammation, calcification, vascularity, oxygen, and temperature. We hypothesized that they also vary in pH and measured pH in living human carotid endarterectomized atherosclerotic plaques (CEA), Watanabe heritable hyperlipidemic (WHHL) rabbit aortas and human umbilical arteries (HUA). METHODS AND RESULTS: We measured pH of CEA of 48 patients, nine WHHL rabbit aortas and 11 HUA specimens (as controls) using a glass type microelectrode mounted on a micromanipulator in a 37 degrees C incubator. We also used single emission and also dual emission fluorescence ratio imaging microscopy employing pH-sensitive probes to confirm pH heterogeneity. Mean pH measured at 415 points of CEA was 7.55+/-0.32; at 275 points of WHHL rabbit aortas it was 7.40+/-0.43; and in 233 points of HUA it was 7.24+/-0.1. In CEA, pH of yellow (lipid-rich) areas was significantly lower than pH in calcified areas (7.15+/-0.01 vs. 7.73+/-0.01, P<0.0001). The coefficients of variation (heterogeneity) of pH in CEA, WHHL rabbit aortas, and HUA were 0.038+/-0.010, 0.039+/-0.007, and 0.009+/-0.003, respectively (P=0.0001). Fluorescence microscopic imaging confirmed pH heterogeneity in both humans and rabbits but not in HUA. In a variance components analysis 82% of the heterogeneity was due to the within-plaque variation and 2% was attributable to between-plaque variation. CONCLUSIONS: Our findings support the hypothesis of pH heterogeneity in plaques, and suggest a possible role for detecting low pH in the detection of plaque vulnerability. The source of pH heterogeneity particularly acidic pH, its impact on the stability of plaques and its potential clinical utility in locating vulnerable plaques remain to be evaluated.