Faculty Bibliography

INTRODUCTION/BACKGROUND:Staphylococcus aureus (S aureus) is the foremost bacterial cause of surgical-site infection (SSI) and is a common source of neuromodulation SSI. Endogenous colonization is an independent risk factor for SSI; however, this risk has been shown to diminish with screening and decolonization. MATERIALS AND METHODS/METHODS:A systematic review was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines using the PubMed, Cochrane Library, and Embase data bases from inception to January 1, 2022, for the purposes of identifying all studies reporting on the use of S aureus swabbing and/or decolonization before neuromodulation procedures. A random-effects meta-analysis was performed using the metaphor package in R to calculate odds ratios (OR). RESULTS: = 0.00). CONCLUSIONS:Preoperative S aureus swabbing and decolonization resulted in significantly decreased odds of infection in neuromodulation procedures. This measure may represent a worthwhile tool to reduce neuromodulation SSI, warranting further investigation.

BACKGROUND:Staged surgery for skull base lesions has been utilized to facilitate maximal safe resection and optimize outcomes while minimizing morbidity and complications. Conversely, staged surgery for primary intraparenchymal neoplasms is less commonly performed and has not been reported as extensively within the literature. As such, we performed a systematic review to examine the unique surgical indications for staging, timing between stages, specific surgical approaches utilized, and postoperative complications of staged surgery for primary intra-axial neoplasms. METHODS:A literature search was conducted in August 2021 using PubMed, Web of Science, and Cochrane databases using the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) recommendations. Titles and abstracts were evaluated independently by 2 authors, after which articles were selected for final analysis based on application of strict inclusion criteria during full text screen. Each included article was then qualitatively assessed and relevant variables-including operative approaches, timing, and outcomes-were extracted for synthesis. RESULTS:Of 115 results, 7 articles were included for final analysis and consisted of 17 pediatric and 4 adult patients. Staged approaches were more commonly utilized in the pediatric patient population for resection of astrocytoma and glioma. Pediatric patients had a timing of surgeries ranging from 5-10 days between operations, compared with 18 days to 4 months in adult patients. Complications in pediatric patients were most commonly hemiparesis, hydrocephalus, cranial nerve VI and VII palsies, truncal ataxia, and cerebellar mutism, while complications in adult patients included language and abstract thinking deficits, respiratory failure, and motor weakness. CONCLUSIONS:This study reports the first comprehensive review of staged surgical procedures for primary, intra-axial cranial neoplasms. There exists a large degree of heterogeneity in complications resulting from staged surgeries for intra-axial neoplasms, which are similar to complications associated with single-stage surgery for intraparenchymal lesions as well as multi-stage surgeries for skull base lesions.

Background: Spinal cord stimulation (SCS) is a well-established, efficacious treatment option for patients suffering from complex regional pain syndrome (CRPS). Psychiatric comorbidities have been shown to be associated with worse SCS outcomes and thus appropriate screening questionnaires have been used to select candidates. This manuscript aims to examine the existing literature regarding the ability for psychiatric screening tools for SCS to adequately identify psychiatric contraindications to SCS and to propose an evidence-based treatment algorithm. Fifteen different psychological screening tools were identified that are used to assess SCS patients. Analysis of the literature revealed the following psychological factors predisposed patients to SCS failure: depression, anxiety, somatization, catastrophizing, poor coping mechanisms, dysfunctional interpersonal relationships, childhood trauma, and elevated pain perception. There was inconclusive evidence regarding the association between the scores from most psychological tests and the aforementioned predisposing factors or SCS outcomes. Conclusion: Based on the existing literature, our group recommends the Beck Depression Inventory (BDI)-II as the primary psychological screening tool for CRPS patients being considered for SCS. Patients with a BDI-II score > 28 should be counseled to undergo cognitive behavioral therapy (CBT) and seek psychiatric care prior to consideration for SCS.

OBJECTIVE/UNASSIGNED:Deep brain stimulation (DBS) allows for direct electrical stimulation of neural circuitry and recording of local field potentials (LFPs). A bibliometric analysis can be implemented to identify studies that have shaped a research field and influenced future study; however, no such analysis investigating the implementation of LFPs in DBS has been performed. The objective of the present study was to identify the most highly cited articles pertaining to DBS LFPs to identify and evaluate the research that has contributed the most to this growing field. METHODS/UNASSIGNED:The Science Citation Index of the Web of Science was implemented to identify the top 84 most cited articles pertaining to DBS LFPs. Information regarding the publication, including author information and study aims, was extracted. RESULTS/UNASSIGNED:The most highly cited articles had had a mean of 109 citations and had been published between 2002 and 2019, with a mode in 2016. The articles had predominantly investigated the subthalamic nucleus (68% of clinical studies) in humans (83.8% of clinical studies). The studies of humans had recruited a mean of 12.5 subjects. Most of the identified articles (56.0%) had reported class III clinical evidence. CONCLUSIONS/UNASSIGNED:The implementation of DBS LFPs is a novel field that is rapidly growing. However, a need exists for more studies with larger patient cohorts and more randomized controlled trials to further elucidate the benefits of this technology. These results will allow for the identification and recognition of the most influential studies pertaining to DBS LFPs, appreciation of the current and future research trends, and inform us regarding areas warranting further investigation.

BACKGROUND:Deep brain stimulation has become an established technology for the treatment of patients with a wide variety of conditions, including movement disorders, psychiatric disorders, epilepsy, and pain. Surgery for implantation of DBS devices has enhanced our understanding of human physiology, which in turn has led to advances in DBS technology. Our group has previously published on these advances, proposed future developments, and examined evolving indications for DBS. SUMMARY/CONCLUSIONS:The crucial roles of structural MR imaging pre-, intra-, and post-DBS procedure in target visualization and confirmation of targeting are described, with discussion of new MR sequences and higher field strength MRI enabling direct visualization of brain targets. The incorporation of functional and connectivity imaging in procedural workup and their contribution to anatomical modelling is reviewed. Various tools for targeting and implanting electrodes, including frame-based, frameless, and robot-assisted, are surveyed, and their pros and cons are described. Updates on brain atlases and various software used for planning target coordinates and trajectories are presented. The pros and cons of asleep versus awake surgery are discussed. The role and value of microelectrode recording and local field potentials are described, as well as the role of intraoperative stimulation. Technical aspects of novel electrode designs and implantable pulse generators are presented and compared.

Intrathecal pumps deliver analgesic medication directly into the central nervous system. In patients with chronic nonmalignant pain, intrathecal therapy using morphine or ziconotide has been shown to be an effective option when traditional noninvasive methods do not provide adequate relief. There has been increasing use of intrathecal drug administration in the management of patients with nonmalignant pain in recent years given the advances in technology and research on the topic. However, due to its invasive nature, intrathecal pumps remain the last option among patients with chronic pain.

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.

Non-specific lower back pain caused by degenerative lumbar disease, such as disc and facet joint degeneration or spondylolisthesis, significantly impairs quality of life of patients and is associated with higher pain scores and reduced function. Patients that fail to respond to conservative treatment may require surgical intervention, such as lumbar interbody fusion (LIF). Compared to other approaches, an anterior approach to lumbar interbody fusion (ALIF) has advantages regarding efficacy of fusion, visualization of relevant anatomy, and a larger allowable size of the interbody fusion device. An anterior approach's main biomechanical advantage includes the ability to restore sagittal alignment, achieve indirect decompression, and provide increased anterior column support. Complications of anterior interbody fusion are mostly approach related and include vascular injury or visceral injury. However, the anterior anatomy can make the placement of an interbody device challenging. In the case reported here, an ALIF procedure was complicated by immobile iliac vessels leaving a small window to place the interbody cage. Continuing with the anterior approach was opted, but with the oblique placement of a cage traditionally used in transforaminal lumbar interbody fusion (TLIF) procedures.

Dimitrios Zambakis was an acclaimed physician at his time, most recognized for his work on leprosy. He theorized that leprosy was a hereditary disease, receiving many awards for his work including the Cholera Medal of Honour (1854), Château-Villard Prize from the Faculty of Medicine in Paris (1898), The Montyon Prize, and the title of Pasha. However, his theory was routinely argued against and was later proven to be invalid. Leprosy is regarded as a contagious disease spread by contact and is not hereditary. The last name appears in research to be spelled in various ways (Zambakis, Zambaco). For the duration of this paper, "Dimitrios Zambakis" will be used.

OBJECTIVE:The aim was to examine research on the impact of spinal cord stimulation (SCS) on the reduction of preimplantation opioid dose and what preimplantation opioid dose is associated with a reduction or discontinuation of opioid use postimplantation. METHODS:Systematic review of literature from PubMed, Web of Science, and Ovid Medline search of "opioid" and "pain" and "spinal cord stimulator." Inclusion criteria included original research providing data on SCS preimplantation opioid dosing and 12 months postimplantation opioid dosing or that correlated specific preimplantation opioid dose or opioid dose cutoff with significantly increased likelihood of opioid use discontinuation at 12 months postimplantation. RESULTS:Systematic review of the literature yielded 17 studies providing data on pre-SCS and post-SCS implantation dose and 4 providing data on the preimplantation opioid dose that significantly increased likelihood of opioid use discontinuation at 12 months postimplantation. Data from included studies indicated that SCS is an effective tool in reducing opioid dose from preimplantation levels at 12 months postimplantation. Data preliminarily supports the assertion that initiation of SCS at a preimplantation opioid dose of ≤20 to ≤42.5 morphine milligram equivalents increases the likelihood of postimplantation elimination of opioid use. DISCUSSION/CONCLUSIONS:SCS is an effective treatment for many types of chronic pain and can reduce or eliminate chronic opioid use. Preimplantation opioid dose may impact discontinuation of opioid use postimplantation and the effectiveness of SCS in the relief of chronic pain. More research is needed to support and strengthen clinical recommendations for initiation of SCS use at lower daily opioid dose.