Digital Preoperative Huddle Platform Use Leads to Decreased Surgical Cost.

BACKGROUND AND OBJECTIVES: Communication has a well-established effect on improving outcomes. The current study evaluated the effect of multidisciplinary preoperative team communication using a digital huddle software platform on operating room costs. METHODS: A digital huddle software platform was implemented in March 2022 for neurosurgical procedures performed at a single tertiary care center. Surgeons were encouraged, but not required, to participate. General linear models were used to test the association between participation and the difference in supply-related cost and case length, using intergroup comparison and historical controls. RESULTS: A total of 29626 cases (performed by 97 surgeons), conducted between March 2021 and June 2023, were included in our analysis. Cases from participating neurosurgeons (12 surgeons, 4064 cases) were compared with cases from nonparticipating neurosurgeons (6 surgeons, 2452 cases), non-neurosurgery cases carried out by the same operating room staff (20 orthopedic spine surgeons, 6073 cases), and non-neurosurgery cases performed in a different operating room unit (59 surgeons, 21 996 cases). In aggregate, operating room (OR) costs increased by 7.3% (95% CI: 0.9-14.1, P = .025) in the postintervention period. In the same period, participation in the digital huddle platform was associated with an OR utilization and supply-related cost decrease of 16.3% (95% CI: 8.3%-23.6%, P < .001). Among neurosurgeons specifically, participation was associated with a supply-related cost decrease of 17.5% (95% CI: 6.0%-27.5%, P = .0037). There was no change in case length (median case length 171 minutes, change: +2.7% increase, 95% CI:-2.2%-7.9%, P = .28). CONCLUSION: The implementation of a digital huddle software platform resulted in an OR utilization and supply cost decrease among participants during a period when the overall nonparticipating control cohort experienced an increase in cost.

Spinal Cord Stimulation: New Waveforms and Technology.

The efficacy of spinal cord stimulation for treating chronic pain has encouraged the development of a wide variety of different technologies for stimulation. In this review, the authors first discuss how parameters of stimulation determine the stimulation waveform. They then discuss new stimulation waveforms, including high frequency and burst stimulation, and the evidence supporting their use. Finally, the authors turn to emerging technologies and techniques including dorsal root ganglion stimulation, wireless stimulation, and closed-loop stimulation.

A broad and variable lumbosacral myotome map uncovered by foraminal nerve root stimulation.

OBJECTIVE: The human myotome is fundamental to the diagnosis and treatment of neurological disorders. However, this map was largely constructed decades ago, and its breadth, variability, and reliability remain poorly described, limiting its practical use. METHODS: The authors used a novel method to reconstruct the myotome map in patients (n = 42) undergoing placement of dorsal root ganglion electrodes for the treatment of chronic pain. They electrically stimulated nerve roots (n = 79) in the intervertebral foramina at T12-S1 and measured triggered electromyography responses. RESULTS: L4 and L5 stimulation resulted in quadriceps muscle (62% and 33% of stimulations, respectively) and tibialis anterior (TA) muscle (25% and 67%, respectively) activation, while S1 stimulation resulted in gastrocnemius muscle activation (46%). However, L5 and S1 both resulted in abductor hallucis (AH) muscle activation (17% and 31%), L5 stimulation resulted in gastrocnemius muscle stimulation (42%), and S1 stimulation in TA muscle activation (38%). The authors also mapped the breadth of the myotome in individual patients, finding coactivation of adductor and quadriceps, quadriceps and TA, and TA and gastrocnemius muscles under L3, L4, and both L5 and S1 stimulation, respectively. While the AH muscle was commonly activated by S1 stimulation, this rarely occurred together with TA or gastrocnemius muscle activation. Other less common coactivations were also observed throughout T12-S1 stimulation. CONCLUSIONS: The muscular innervation of the lumbosacral nerve roots varies significantly from the classic myotome map and between patients. Furthermore, in individual patients, each nerve root may innervate a broader range of muscles than is commonly assumed. This finding is important to prevent misdiagnosis of radicular pathologies.

Perioperative team communication through a mobile app for improving coordination and education in neurosurgery cases.

OBJECTIVE: Miscommunication and poor coordination among surgical teams are known causes of preventable medical harms and operating room inefficiencies and inhibit surgical training. Technology may help overcome these challenges. This study used the personal experience of one of the authors as a former Air Force F-15 pilot to design a combat aviation pre- and postoperative communication workflow in the neurosurgery department and tested its effect on safety, efficiency, and education. The authors hypothesized that the adoption of this workflow through a tailored technological platform will increase compliance and improve the chances of sustainability. METHODS: Data were prospectively collected from neurosurgery cases before (January-May 2020) and after (June-October 2020) implementation of this workflow. Briefing and debriefing were executed using a custom mobile platform and were defined as nonmandatory for all participants. All faculty and residents who operated at NYU Langone Medical Center (Tisch campus) during the intervention period were enrolled on the platform. Primary outcomes were morbidity and mortality per the department's criteria, and intraoperative last-minute requests as reported by operating room staff in a double-blinded fashion. Secondary outcomes were user responses on the subjective questionnaires. RESULTS: Data were collected from 637 and 893 cases during the preintervention and intervention periods, respectively. The average briefing rates for residents and surgeons were 71% and 81%, respectively, and the average debriefing rates for residents and surgeons were 67% and 88%. There was no significant difference in preoperative risk score between the preintervention and intervention patient populations (p = 0.24). The rate of intraoperative last-minute requests significantly decreased from 16.6% (35/211) to 10.5% (35/334, p = 0.048). There was no significant change in morbidity and mortality between the preintervention and intervention periods. On subjective questionnaires there was a statistically significant improvement in safety, efficiency, and educational aspects of the cases during the intervention period. CONCLUSIONS: Implementation of aviation-like structured team communication practices in the neurosurgery department through a technological platform improved education and communication between surgical teams and led to a reduction in last-minute surgical requests that could impact costs.

The incidence and predictors of new brain metastases in patients with non-small cell lung cancer following discontinuation of systemic therapy.

OBJECTIVE: Patients with non-small cell lung cancer (NSCLC) metastatic to the brain are living longer. The risk of new brain metastases when these patients stop systemic therapy is unknown. The authors hypothesized that the risk of new brain metastases remains constant for as long as patients are off systemic therapy. METHODS: A prospectively collected registry of patients undergoing radiosurgery for brain metastases was analyzed. Of 606 patients with NSCLC, 63 met the inclusion criteria of discontinuing systemic therapy for at least 90 days and undergoing active surveillance. The risk factors for the development of new tumors were determined using Cox proportional hazards and recurrent events models. RESULTS: The median duration to new brain metastases off systemic therapy was 16.0 months. The probability of developing an additional new tumor at 6, 12, and 18 months was 26%, 40%, and 53%, respectively. There were no additional new tumors 22 months after stopping therapy. Patients who discontinued therapy due to intolerance or progression of the disease and those with mutations in RAS or receptor tyrosine kinase (RTK) pathways (e.g., KRAS, EGFR) were more likely to develop new tumors (hazard ratio [HR] 2.25, 95% confidence interval [CI] 1.33-3.81, p = 2.5 × 10-3; HR 2.51, 95% CI 1.45-4.34, p = 9.8 × 10-4, respectively). CONCLUSIONS: The rate of new brain metastases from NSCLC in patients off systemic therapy decreases over time and is uncommon 2 years after cessation of cancer therapy. Patients who stop therapy due to toxicity or who have RAS or RTK pathway mutations have a higher rate of new metastases and should be followed more closely.

Distinct population code for movement kinematics and changes of ongoing movements in human subthalamic nucleus.

The subthalamic nucleus (STN) is theorized to globally suppress movement through connections with downstream basal ganglia structures. Current theories are supported by increased STN activity when subjects withhold an uninitiated action plan, but a critical test of these theories requires studying STN responses when an ongoing action is replaced with an alternative. We perform this test in subjects with Parkinson's disease using an extended reaching task where the movement trajectory changes mid-action. We show that STN activity decreases during action switches, contrary to prevalent theories. Furthermore, beta oscillations in the STN local field potential, which are associated with movement inhibition, do not show increased power or spiking entrainment during switches. We report an inhomogeneous population neural code in STN, with one sub-population encoding movement kinematics and direction and another encoding unexpected action switches. We suggest an elaborate neural code in STN that contributes to planning actions and changing the plans.

Transclival Approach for Resection of a Pontine Cavernous Malformation: 2-Dimensional Operative Video.

Cerebral cavernous malformations are common vascular anomalies consisting of a cluster of capillaries without intervening brain tissue.1 A variety of approaches for resection have been undertaken,2 and a handful of case reports have described the endoscopic, endonasal, transclival approach.3 We present a case of a 51-yr-old woman with lupus and hepatitis B-associated cirrhosis who presented with diplopia, dysphagia, and ataxia. She had a left abducens nerve palsy and magnetic resonance imaging (MRI) showed a left pontine cavernous malformation. After a repeat hemorrhage, she consented to surgical resection. The lesion appeared to come to the medial pontine pial surface. Tractography indicated a rightward displacement of the left corticospinal tract. Therefore, an endoscopic, transnasal, transclival approach was chosen. A lumbar drain was placed preoperatively. The clivus and ventral petrous bone were drilled using the vidian canal to help identify the anterior genu of the petrous carotid artery. The clival dura was opened, revealing the abducens nerve exiting the ventral pons. The cavernoma was visible on the surface lateral to the nerve. It was removed using blunt dissection and the remaining cavity inspected. The skull base was reconstructed using an abdominal dermal-fat graft and Alloderm covered by a nasoseptal flap. Postoperatively she had transient swallowing difficulty. The lumbar drain was kept open for 5 d. Cerebrospinal fluid (CSF) leak was ruled out using an intrathecal fluorescein injection. She was discharged home, but presented 2 wk postoperatively with aseptic meningitis, which was treated supportively. Postoperative imaging did not show residual cavernoma.

Deep Brain Stimulation of the Subthalamic Nucleus Induces Impulsive Responses to Bursts of Sensory Evidence.

Decisions are made through the integration of external and internal inputs until a threshold is reached, triggering a response. The subthalamic nucleus (STN) has been implicated in adjusting the decision bound to prevent impulsivity during difficult decisions. We combine model-based and model-free approaches to test the theory that the STN raises the decision bound, a process impaired by deep brain stimulation (DBS). Eight male and female human subjects receiving treatment for Parkinson's disease with bilateral DBS of the STN performed an auditory two-alternative forced choice task. By ending trials unpredictably, we collected reaction time (RT) trials in which subjects reached their decision bound and non-RT trials in which subjects were forced to make a decision with less evidence. A decreased decision bound would cause worse performance on RT trials, and we found this to be the case on left-sided RT trials. Drift diffusion modeling showed a negative drift rate. This implies that in the absence of new evidence, the amount of evidence accumulated tends to drift toward zero. If evidence is accumulated at a constant rate this results in the evidence accumulated reaching an asymptote, the distance of which from the bound was decreased by DBS (p = 0.0079, random shuffle test), preventing subjects from controlling impulsivity. Subjects were more impulsive to bursts of stimuli associated with conflict (p < 0.001, cluster mass test). In addition, DBS lowered the decision bound specifically after error trials, decreasing the probability of switching to a non-RT trial after an error compared to correct response (28% vs. 38%, p = 0.005, Fisher exact test). The STN appears to function in decision-making by modulating the decision bound and drift rate to allow the suppression of impulsive responses.

Betweenness centrality of intracranial electroencephalography networks and surgical epilepsy outcome.

OBJECTIVE: We sought to determine whether the presence or surgical removal of certain nodes in a connectivity network constructed from intracranial electroencephalography recordings determines postoperative seizure freedom in surgical epilepsy patients. METHODS: We analyzed connectivity networks constructed from peri-ictal intracranial electroencephalography of surgical epilepsy patients before a tailored resection. Thirty-six patients and 123 seizures were analyzed. Their Engel class postsurgical seizure outcome was determined at least one year after surgery. Betweenness centrality, a measure of a node's importance as a hub in the network, was used to compare nodes. RESULTS: The presence of larger quantities of high-betweenness nodes in interictal and postictal networks was associated with failure to achieve seizure freedom from the surgery (p < 0.001), as was resection of high-betweenness nodes in three successive frequency groups in mid-seizure networks (p < 0.001). CONCLUSIONS: Betweenness centrality is a biomarker for postsurgical seizure outcomes. The presence of high-betweenness nodes in interictal and postictal networks can predict patient outcome independent of resection. Additionally, since their resection is associated with worse seizure outcomes, the mid-seizure network high-betweenness centrality nodes may represent hubs in self-regulatory networks that inhibit or help terminate seizures. SIGNIFICANCE: This is the first study to identify network nodes that are possibly protective in epilepsy.

Epigallocatechin-3-gallate is a potent phytochemical inhibitor of intimal hyperplasia in the wire-injured carotid artery.

OBJECTIVE: Epigallocatechin-3-gallate (EGCG), a catechin gallate ester, is the major component of green tea and has been demonstrated to inhibit tumor growth as well as inhibit smooth muscle cell migration. We evaluated the effect of the phytochemicals resveratrol, allicin, sulforaphane (SFN), and EGCG on intimal hyperplasia in the carotid artery injury model. METHODS: Intimal hyperplasia was induced in carotid arteries of adult Sprague-Dawley rats with a wire injury. Experimental animals received intraperitoneal injections of one of the four phytochemicals daily beginning 1 day prior to surgery and continued for up to 4 weeks. Control animals were administered saline. Carotid specimens were harvested at 2 weeks and subjected to quantitative image analysis. In addition, EGCG specimens were analyzed for cell proliferation, immunohistochemistry, and Western blot analysis. RESULTS: Quantitative image analysis showed significant phytochemical suppression of intimal hyperplasia at 2 and 4 weeks postoperatively with EGCG (62% decrease in intimal area). Significant decreases were also noted at 2 weeks for SFN (56%) and resveratrol (44%), whereas the decrease with allicin (24%) was not significant. Quantification of intimal hyperplasia by intima:media ratio showed similar results. Cell proliferation assay of specimens demonstrated suppression by EGCG. Immunohistochemical staining of EGCG-treated specimens showed extracellular signal-regulated kinase (ERK) suppression but not of the c-jun N-terminal kinase or p38 pathways. Western blot analysis confirmed reduced ERK activation in arteries treated with EGCG. CONCLUSIONS: Intraperitoneal injection of the phytochemicals EGCG, SFN, resveratrol, and allicin have suppressive effects on the development of intimal hyperplasia in the carotid artery injury model, with maximal effect due to EGCG. The mechanism of EGCG action may be due to inhibition of ERK activation. EGCG may affect a common pathway underlying either neoplastic cellular growth or vascular smooth muscle cellular proliferation.