Augmented reality–assisted microsurgical resection of brain arteriovenous malformations: illustrative case

Background: Arteriovenous malformations (AVMs) of the brain are vessel conglomerates of feeding arteries and draining veins that carry a risk of spontaneous and intraoperative rupture. Augmented reality (AR)-assisted neuronavigation permits continuous, real-time, updated visualization of navigation information through a heads-up display, thereby potentially improving the safety of surgical resection of AVMs. Observations: The authors report a case of a 37-year-old female presenting with a 2-year history of recurrent falls due to intermittent right-sided weakness and increasing clumsiness in the right upper extremity. Magnetic resonance imaging, magnetic resonance angiography, and cerebral angiography of the brain revealed a left parietal Spetzler-Martin grade III AVM. After endovascular embolization of the AVM, microsurgical resection using an AR-assisted neuronavigation system was performed. Postoperative angiography confirmed complete obliteration of arteriovenous shunting. The postsurgical course was unremarkable, and the patient remains in excellent health. Lessons: Our case describes the operative setup and intraoperative employment of AR-assisted neuronavigation for AVM resection. Application of this technology may improve workflow and enhance patient safety

Aspiration thrombectomy of M2 middle cerebral artery occlusion to treat acute ischemic stroke: A core lab–adjudicated subset analysis from the COMPLETE registry and literature review

Background Although the benefits of aspiration thrombectomy for treating acute ischemic stroke caused by proximal large vessel occlusion have been established, fewer data are available for evaluating aspiration thrombectomy of distal occlusion. The objective of this study was to evaluate, by means of prospectively collected data, the safety and efficacy of aspiration thrombectomy in patients with M2 middle cerebral artery (MCA) occlusion. Methods This study is a subset analysis of a global prospective multicenter observational registry that included patients who presented with either anterior or posterior large vessel occlusion and were eligible for mechanical thrombectomy using the Penumbra System including the Penumbra 3D Revascularization Device. For this analysis, all patients in the registry with M2 MCA occlusion were included. Results Of the 650 patients in the registry, 113 (17.4%) had M2 MCA occlusion. The rate of a modified treatment in cerebral infarction score of 2b to 3 after the procedure was 79.6% (90/113), the rate of a modified Rankin Scale score of 0–2 at 90 days was 72.5% (79/109), and the all-cause mortality rate at 90 days was 8.8% (10/113). Device-related serious adverse events occurred in one patient (0.9%) within 24 h and in two patients (1.8%) overall. Procedure-related serious adverse events occurred in four patients (3.5%) within 24 h and in six patients (5.3%) overall (nine events). Conclusion For appropriately selected patients, aspiration thrombectomy for acute ischemic stroke due to M2 MCA occlusion was safe and effective, with high rates of technical success and good functional outcome

Case Volume Justification of 3D-Navigated Spinal Procedures: A Cost-Benefit Analysis

Abstract 3D image-guidance platforms have transformed spinal surgery by enhancing visualization, increasing precision, and improving patient outcomes. However, with high procurement, operational, and maintenance costs relative to the standard of care, the benefits of acquiring these platforms must be thoroughly assessed. This study aims to develop a model that weighs the cost of a typical 3D navigation platform against its clinical benefits to determine the facility case volume required to justify its purchase. Using Medtronic’s StealthStation and O-Arm as a market example, we calculated the break-even case volume by dividing the cost of the platform by the difference in gross margins between 3D navigation and the standard of care. Total gross margins earned from first-time and revision surgeries were calculated based on each payer’s reimbursement rate and covered case volume, as well as each technology’s revision rate. Values reported in literature and by Centers for Medicare and Medicaid Services databases were plugged into the model to calculate variables. At a 0% reimbursement rate from private payers for revision surgeries, an annual case volume of 158 spinal surgeries would be required to justify the per-year 3D navigation cost; at 100% private payer reimbursement, 352 surgeries would be required. Given these volumes, 61% of all US inpatient facilities cannot justify 3D navigation at 0% reimbursement, and 86% cannot justify it at 100% reimbursement. Accordingly, greater pricing flexibility, such as per-procedure models, is required for 3D navigation systems to standardize clinical outcomes across medical centers

Survey of disease pressures in twenty-six niche herds in the midwestern United States

Objective: To provide diagnostic and veterinary support to niche producers in order to generate information on disease pressures in niche herds. Materials and methods: Twenty-six producers under contract with three niche-marketing companies were accepted into the program. A standardized diagnostic protocol, including serology and tissue diagnostics, was undertaken on suckling, nursery, finishing, and breeding animals. The diagnostic frequencies of diseases in niche-pork systems were compared to those in age-matched, diseased pigs submitted to the Iowa State University Veterinary Diagnostic Laboratory (ISU VDL) or in published reports. Results: Overall seroprevalence was lower (P P Mycoplasma hyopneumoniae and porcine circovirus type 2 were detected in a higher percentage of niche pigs with respiratory disease (P Lawsonia intracellularis enteritis (P Implications: Niche producers typically raise pigs in continuous-flow systems, without antibiotics, and in different environments than larger commercial swine operations. Results of this study indicate that these production changes can contribute to differences in the diagnostic frequency of several diseases and the ages at which diseases are clinically manifest in niche herds.This article is published as Yaeger, Michael J., Locke A. Karriker, Lori Layman, Patrick G. Halbur, Gary H. Huber, and Kurt Van Hulzen. "Survey of disease pressures in twenty-six niche herds in the midwestern United States." Journal of Swine Health and Production 17, no. 5 (2009): 256-263. Posted with permission.</p

Cytological analysis of small branch-duct intraductal papillary mucinous neoplasms provides a more accurate risk assessment of malignancy than symptoms

The Sendai guidelines for management of patients with clinically suspected intraductal papillary mucinous neoplasms (IPMN) recommend resection of cysts > 30 mm, a dilated main pancreatic duct (MPD) > 6 mm, a mural nodule (MN), symptoms or positive cytology. Although sensitive, asymptomatic cysts, nonspecific symptoms, and a high threshold for positive cytology limit the specificity of the guidelines. We have assessed the value of cytology relative to symptom for predicting malignancy in IPMNs without high-risk imaging features

Mechanisms of Peer Review and their Potential Impact on Neurosurgeons: A Pilot Survey

INTRODUCTION: Physician peer review is a universal practice among United States hospitals. While there are many commonalities in peer review procedures, many of them established by law, there is also much institutional variation which should be well understood by practicing neurosurgeons. METHODS: We conducted a 13-question pilot survey of a sample of five hospital systems with whom members of the CSNS-Medicolegal committee are affiliated. Survey questions were constructed to qualitatively assess three features of Hospital Peer Review: (1) committee composition and process, (2) committee outcomes, and (3) legal protections and ramifications RESULTS: The most common paradigm for physician peer review committee (PPRC) was an interdisciplinary group with representatives from most major medical and surgical subspecialties. Referrals for peer review inquiry could be made by any hospital employee and were largely anonymous. Most institutions included a pre-committee screening process conducted by the PPRC leadership. The most common outcomes of an inquiry were resolution with no further action or ongoing focused professional practice evaluation (FFPE). Only in rare circumstances were hospital privileges reported to be revoked or terminated. Members of the PPRC were consistently protected from retaliatory litigation related to peer review participation. The majority of hospitals had a multi-layered decision process and availability of appeal to minimize the potential for punitive investigations. DISCUSSION: According to a recent study, only 62% of hospitals consider their peer review process to be highly or significantly standardized. This pilot survey provides commentary of potential areas of commonality and variation among hospital peer review practices

Clinical impact of intraoperative hyperlactatemia during craniotomy.

OBJECT:Patients often develop markedly elevated serum lactate levels during craniotomy although the reason for this is not entirely understood. Elevated lactate levels have been associated with poor outcomes in critically ill septic shock patients, as well as patients undergoing abdominal and cardiac surgeries. We investigated whether elevated lactate in craniotomy patients is associated with neurologic complications (new neurological deficits) as well as systemic complications. METHODS:We performed a cohort study of elective craniotomy patients. Demographic and intraoperative data were collected, as well as three timed intraoperative arterial lactate values. Additional lactate, creatinine and troponin values were collected immediately postoperatively as well as 12 and 24 hours postoperatively. Assessment for neurologic deficit was performed at 6 hours and 2 weeks postoperatively. Hospital length-of-stay and 30-day mortality were collected. RESULTS:Interim analysis of 81 patients showed that no patient had postoperative myocardial infarction, renal failure, or mortality within 30 days of surgery. There was no difference in the incidence of new neurologic deficit in patients with or without elevated lactate (10/26, 38.5% vs. 15/55 27.3%, p = 0.31). Median length of stay was significantly longer in patients with elevated lactate (6.5 vs. 3 days, p = 0.003). Study enrollment was terminated early due to futility (futility index 0.16). CONCLUSION:Elevated intraoperative serum lactate was not associated with new postoperative neurologic deficits, other end organ events, or 30 day mortality. Serum lactate was related to longer hospital stay

Wide-neck aneurysms: Systematic review of the neurosurgical literature with a focus on definition and clinical implications

OBJECTIVE Wide-necked aneurysms (WNAs) are a variably defined subset of cerebral aneurysms that require more advanced endovascular and microsurgical techniques than those required for narrow-necked aneurysms. The neurosurgical literature includes many definitions of WNAs, and a systematic review has not been performed to identify the most commonly used or optimal definition. The purpose of this systematic review was to highlight the most commonly used definition of WNAs. METHODS The authors searched PubMed for the years 1998.2017, using the terms gwide neck aneurysm h and gbroad neck aneurysm h to identify relevant articles. All results were screened for having a minimum of 30 patients and for clearly stating a definition of WNA. Reference lists for all articles meeting the inclusion criteria were also screened for eligibility. RESULTS The search of the neurosurgical literature identified 809 records, of which 686 were excluded (626 with \u3c 30 patients; 60 for lack of a WNA definition), leaving 123 articles for analysis. Twenty-seven unique definitions were identified and condensed into 14 definitions. The most common definition was neck size ≥ 4 mm or dome-to-neck ratio \u3c 2, which was used in 49 articles (39.8%). The second most commonly used definition was neck size ≥ 4 mm, which was used in 26 articles (21.1%). The rest of the definitions included similar parameters with variable thresholds. There was inconsistent reporting of the precise dome measurements used to determine the dome-to-neck ratio. Digital subtraction angiography was the only imaging modality used to study the aneurysm morphology in 87 of 122 articles (71.3%). CONCLUSIONS The literature has great variability regarding the definition of a WNA. The most prevalent definition is a neck diameter of . 4 mm or a dome-to-neck ratio of \u3c 2. Whether this is the most appropriate and clinically useful definition is an area for future study

Cytology adds value to imaging studies for risk assessment of malignancy in pancreatic mucinous cysts

Evaluate the value of cytology relative to imaging features in risk assessment for malignancy as defined in the Sendai Guidelines