Common Neurosurgical Procedure Research Articles

Reduced temporal muscle thickness predicts shorter survival in patients undergoing chronic subdural haematoma drainage.

Chronic subdural haematoma (CSDH) drainage is a common neurosurgical procedure. CSDHs cause excess mortality, which is exacerbated by frailty. Sarcopenia contributes to frailty - its key component, low muscle mass, can be assessed using cross-sectional imaging. We aimed to examine the prognostic role of temporal muscle thickness (TMT) measured from preoperative computed tomography head scans among patients undergoing surgical CSDH drainage. We retrospectively identified all patients who underwent CSDH drainage within 1year of February 2019. We measured their mean TMT from preoperative computed tomography scans, tested the reliability of these measurements, and evaluated their prognostic value for postoperative survival. One hundred and eighty-eight (122, 65% males) patients (median age 78years, IQR 70-85years) were included. Thirty-four (18%) patients died within 2years, and 51 (27%) died at a median follow-up of 39months (IQR 34-42months). Intra- and inter-observer reliability of TMT measurements was good-to-excellent (ICC 0.85-0.97, P<0.05). TMT decreased with age (Pearson's r=-0.38, P<0.001). Females had lower TMT than males (P<0.001). The optimal TMT cut-off values for predicting two-year survival were 4.475mm for males and 3.125mm for females. TMT below these cut-offs was associated with shorter survival in both univariate (HR 3.24, 95% CI 1.85-5.67) and multivariate (HR 1.86, 95% CI 1.02-3.36) analyses adjusted for age, ASA grade and bleed size. The effect of TMT on mortality was not mediated by age. In patients with CSDH, TMT measurements from preoperative imaging were reliable and contained prognostic information supplemental to previously known predictors of poor outcomes.

Effect of cranial entry site on the rate of proximal catheter misplacement in ventriculoperitoneal shunt insertion.

The insertion of a ventriculoperitoneal shunt (VPS) is a common neurosurgical procedure, but the optimal entry site of the ventricular catheter is still under debate. In this study, the authors compare the parietal (Keen's) and frontal (Kocher's) entry sites in terms of the rate of revision surgery due to ventricular catheter misplacement, VPS dysfunction, and VPS infection. The authors retrospectively analyzed the data on consecutive adults (age ≥ 18 years) who had undergone primary VPS insertion between 2010 and 2020 at two neurosurgical centers. One center regularly inserts the ventricular catheter frontally (frontal group); the other center, parietally (parietal group). The primary outcome of interest was the rate of ventricular catheter misplacement necessitating revision surgery. Secondary outcomes were functional outcome as measured by the modified Rankin Scale (mRS), rate of revision surgery for VPS dysfunction and infection, as well as early (≤ 30 days) and late (> 30 days) mortality rates. Propensity score matching was performed based on baseline variables, such as normal pressure hydrocephalus, postinfectious hydrocephalus, and idiopathic intracranial hypertension, which were identified as predictors of ventricular catheter misplacement using logistic regression analysis. Among 539 consecutive patients, 301 (55.8%) were in the frontal group and 238 (44.2%) in the parietal group. Postoperative rates of revision surgery due to misplacement were comparable in the two catheter entry site groups (frontal 14 [4.7%] vs parietal 11 [4.6%], p = 0.987). Rates of revision surgery for VPS dysfunction (14 [4.7%] vs 10 [4.2%], respectively, p = 0.802) and infection (22 [7.3%] vs 10 [4.2%], p = 0.13) exhibited no significant differences. Favorable functional outcomes (mRS score ≤ 2; 164 [76.3%] vs 174 [79.5%], respectively, p = 0.058) and early mortality rates (5 [1.7%] vs 6 [2.5%], p = 0.483) were similar between the groups. After propensity score matching, the primary and secondary outcome measures remained comparable between the groups. The entry site of the ventricular catheter in VPS surgery does not seem to affect proximal revision rates. Further, revision rates due to VPS dysfunction, VPS infection, and morbidity were comparable as well.

Flexible low-profile external ventricular drain catheter for real-time brain monitoring

External ventricular drainage is one of the most common neurosurgical procedures in the world for acute hydrocephalus, which must be performed carefully by a neurosurgeon. Although various neuromonitoring external ventricular drain (EVD) catheters have been utilized, they still suffer from rigidity and bulkiness to mitigate post-EVD placement trauma. Here, we introduce a flexible and low-profile smart EVD catheter using a class of technologies with sensitive electrical materials, seamless integration, and flexible mechanics, which serves as a highly soft and minimally invasive device to monitor electrical brain signals. This device reliably captures biopotentials in real time while exhibiting remarkable flexibility and reliability. The seamless integration of its sensory system promises a minimally invasive EVD placement on brain tissue. This work validates the device's distinct characteristics and performances through in vitro experiments and computational analysis. Collectively, this device's exceptional patient- and user-friendly attributes highlight its potential as one of the most practical EVD catheters.

Ventricular Access Utilizing Cutaneous Reference Points: Statistical Analysis and Proposal of a New Ventricular Entry Point

Perform radiologic measurements and analysis of normal brain computed tomography (CT) scans; delineate a new ventricular entry point from cutaneous landmarks, highlighting the potential surgical implications of these findings. Six radiologic distances (AR; BR; AL; BL, C, and D) were measured in normal brain CT scans using Horos software. Statistical analysis of the measurements was performed with minitab18 software based on age, sex, and side. 132 brain CT scans were analyzed, yielding the following mean results: AR distance: 2.1cm; BR distance: 7cm; AL distance: 2.1cm; BL distance: 7.1cm; C distance: 12.4cm; D distance: 7cm; new ventricular entry point: 12.4cm posterior to the nasion, and 2.1cm lateral to the midline. The freehand technique for accessing the lateral ventricles is a common neurosurgical procedure but is often accompanied by complications. To address this, we suggest a novel entry point for ventricular access, determined by cutaneous reference points. This point is situated 12.4cm posterior to the nasion along the midline and 2.1cm lateral to the midline. Although our findings may play a role in presurgical planning for ventricular pathologies, future prospective studies are warranted.

114 Compliance with Federal Price Transparency Rules at US Hospitals With Neurosurgical Training Programs

INTRODUCTION: The Centers for Medicare &amp; Medicaid Services implemented federal requirements on January 1st, 2021 that require hospitals to provide a list of payer-negotiated prices in a machine-readable file. METHODS: We performed a cross-sectional analysis in March of 2023 of 116 US hospitals associated with a neurosurgical training program to assess compliance with the new federal requirements by searching “price transparency” or “standard charges” with associated hospital on the internet to download machine readable files. The payer-negotiated price for 11 common neurosurgical procedures based on CPT codes for 4 insurance companies were collected (Aetna,Anthem/BCBS,United,Medicare). Pricing using DRG codes were excluded given the range of neurosurgical procedures that are encompassed by a specific DRG code. RESULTS: 92/116 (79.3%) hospitals were compliant with the requirement for machine-readable file with payer-negotiated prices. 45/92 (48.9%) used DRG codes. For the common neurosurgical procedures, hospitals had negotiated price available for at least one insurance company with average private insurance cost and average Medicare costs as follows: ventriculoperitoneal shunt (21/92;$10,698;$1,919), lumbar laminectomy (20/92;$10,343;$4,460), lumbar microdiscectomy (31/92;$9,374;$5,026), anterior cervical discectomy and fusion (28/92;$11,544;$9,859), deep brain stimulator with microelectrode recording (15/92;$10,510;$3,616), craniotomy for tumor (14/92;$6,951;$2,361), stereotactic radiosurgery for brain (18/92;$22,409;$7,362) and spine (14/92;$14,242;$3,306), intrathecal pump placement (31/92;$7,139;$5,064), intracranial aneurysm endovascular treatment (14/92;$9,452;$3352), and diagnostic angiogram (46/92;$11,295;$5,867). CONCLUSIONS: While hospital compliance with federal requirement for machine readable files with payer-negotiated prices was high, availability of payer-negotiated prices for 4 major insurance types across 11 common neurosurgical procedures based on CPT code was sparce. Overall, meaningful conclusions on procedural related cost for elective procedures will be difficult for patients to make due to the unintelligible format of data and a lack of reporting of cost per CPT code in a comprehensive manner.

Opiate-reduction protocol for common outpatient spinal procedures: a long-term feasibility study and single-center experience.

The opioid epidemic continues to be at the forefront of public health. As a response to this crisis, many statewide and national medical groups have sought to develop opioid-prescribing guidelines for both acute and chronic pain states. Given the lack of evidence in the neurosurgical landscape, the authors' institution implemented opioid-prescribing guidelines for common outpatient spinal procedures in 2017, subsequently demonstrating a significant reduction in the narcotics prescribed. However, the ability to maintain the results garnered from such guidelines long term has not been described. The objective of this study was to evaluate postoperative opioid utilization at a high-volume quaternary referral center 5 years after the initial implementation of an opioid-reduction protocol for common outpatient spinal procedures. From the electronic medical records, authors collected data on the number of tablets and total morphine equivalent dose (MED) prescribed, acute postoperative readmissions for pain concerns, refill requests, and conversion to long-term opiate use in the 5 years following implementation of an opioid-reduction protocol for common outpatient spinal procedures. These procedures, undertaken in opiate-naive patients, included 1- or 2-level anterior cervical discectomy and fusion, 1- or 2-level cervical disc replacement, and 1- or 2-level laminectomy, laminotomy, or foraminotomy (cervical or lumbar). The total quantity of narcotics was reduced by 37.0 tablets per patient after protocol implementation and over the 5-year period thereafter. Generally, patients were discharged with an average of 23.3 tablets, concurrent with the initial goal of 24 tablets, set forth in 2017. These results confirm an ongoing reduction in opiate quantities prescribed and overall morphine equivalent totals at the time of discharge over the course of 5 years after initial protocol implementation. A standardized discharge protocol for postoperative outpatient spinal procedures can lead to long-term reductions in opioid discharge quantity, without compromising patient safety or increasing the utilization of hospital resources through readmissions, refill requests, or clinic phone calls. This study provides an example of a feasible and effective discharge prescription regimen that may be generalizable to common outpatient neurosurgical procedures with long-term evidence that a small intervention can lead to ongoing reduced quantities of postoperative opioids at the time of discharge.

165 Can Artificial Intelligence Successfully Identify CPT Codes for Common Procedures in Neurosurgery?

INTRODUCTION: Coding for Neurosurgical procedures is a complex process that is dynamically changing year to year, through the introduction and removal of codes and modifiers every year. It is an increasing challenge for Neurosurgeons to keep up with the changes and implement them in their practice to ensure accurate coding and maximize billing. The AANS reports only 43% of Neurosurgeons are estimated to have certified professional coders. METHODS: ChatGPT was asked to provide CPT codes for common neurosurgical procedures of the brain and spine with a given indication for the procedure. The responses of ChatGPT were recorded and compared to the accurate CPT codes used for the procedure. The total amount of RVUs provided by Chat GPT CPT codes were compared to the actual amount of RVUs for the given procedure. RESULTS: ChatGPT was asked for four cranial and spinal procedures each. In terms of accuracy, three responses were completely inaccurate, four responses were partially correct, and one response was completely correct. From the total 8 cases, ChatGPT provided CPT codes accounting for 132.88 of 227.33 expected RVUs (58.5%). For spinal procedures ChatGPT provided 81.7 of 107.8 expected RVUs (75.8%). For cranial procedures ChatGPT provided 51.2 of 119.5 expected RVUs (42.8%). CONCLUSIONS: The ability of ChatGPT to successfully code for neurosurgical procedures appears to be limited at this time, but it is not without promise. The information to successfully code for billing for medical procedures is not readily available on the internet. Using limited information ChatGPT is still able to successfully identify codes being used for procedures. Teaching artificial intelligence to use CPT codes for billing could offer neurosurgeons increased efficiency and efficacy in their billing in the future.

879 Comparison of Perioperative and Long-Term Outcomes Following PEEK and Autologous Cranioplasty: A Single Institution Experience

INTRODUCTION: Cranioplasty is a common neurosurgical procedure to correct congenital or acquired skull defects. Three-dimensionally (3D) printed polyether-ether-ketone (PEEK) implants are a relatively novel option for cranioplasty that has gained popularity in recent years. However, there is ongoing debate with respect to this material’s efficacy and safety compared to autologous bone grafts. The purpose of this study was to offer our institution’s experience and add to the growing body of literature on the topic. METHODS: A single-institution retrospective analysis of patients undergoing cranioplasties between 2016 and 2021 was performed. Patients were divided into PEEK and autologous cranioplasty cohorts. Parameters of interest included patient demographics as well as perioperative (&lt;3 months postoperative) and long-term outcomes (&gt;3 months postoperative). A p-value &lt;0.05 was considered statistically significant. RESULTS: A total of 31 patients met inclusion criteria (PEEK: 15, Autologous: 16). Mean age of the entire cohort was 51.7 years (range 19-81 years). Baseline demographics using the modified frailty index (mFI) revealed greater rate of comorbidities in the autologous group (p = 0.073), which was accounted for in statistical analyses. Multiple logistic regression model revealed a significantly higher rate of surgical site infection during the immediate postoperative period in the autologous cohort (31.3% vs. 0%, p = 0.011). Otherwise, perioperative and long-term complication profiles were similar between groups. Additionally, a generalized linear model demonstrated that both cohorts had similar mean hospital length of stay (LoS) (autologous: 16.1 vs. PEEK: 10.7 days). CONCLUSIONS: PEEK cranioplasty implants may offer a more favorable perioperative complication profile with similar long-term complication rates and hospital LoS compared to autologous bone implants. Future studies are warranted to confirm our findings in larger series, and further examine the utility of PEEK in cranioplasty.

Through the Looking Glass: Comparing Resident and Attending Views on Competency and Autonomy

ObjectivesSurgical residencies act as an apprenticeship to train new surgeons, ideally with increasing trainee autonomy and competency. Objective methods of measuring these two qualities are needed. MethodsThe objective of this pilot study is to use the Surgical Autonomy Program (SAP) to compare resident and attending perception of competency, via Zones of Proximal Development (ZPDs), and autonomy, via TAGS (Teach, Advise, Guide, Solo) scale for a common pediatric neurosurgical procedure. The most common pediatric neurosurgical procedure, a ventriculoperitoneal shunt, was broken down into four ZPDs. After each procedure, the resident and the attending rated the competency of the resident by ZPD, and their autonomy using TAGS. These ratings were then compared to see if the attending and the resident agreed on their levels of competency and autonomy. ResultsThere were no significant difference in the rating of competency or autonomy between the residents and the attendings. Post graduate year (PGY) was significantly associated with differences in TAGS ratings with those having less experience showing a positive perception gap. Other covariates (age, gender) were not associated with differences in rating. The residents found that the ZPDs checklist was a useful tool for communicating with the attending and for getting appropriate autonomy in the OR. ConclusionsPediatric neurosurgical trainees and attendings had concordance on their perceptions of resident autonomy and competency, suggesting that this tool could be a useful way of objectively grading the progress of neurosurgical residents in surgery.

Titanium mesh cranioplasty for cosmetically disfiguring cranio-facial tumours in a resource limited setting

BackgroundThe aesthetic reconstruction of disfiguring cranio-facial defects after tumour excision can be quite challenging to the neurosurgeon with limited resources. The choice of cranioplasty implant, intraoperative technicalities and the patients’ postoperative appearance are critical considerations in management. There are a number of synthetic materials available for cranioplasty, however, the customised implants are not readily available in our practice setup. They are also mostly constructed and contoured after the bony defect has been created or require sophisticated software construction pre-operatively. MethodsEight patients with cranio-facial tumour pathologies who presented to our neurosurgical service, and had titanium mesh cranioplasty for the correction of cosmetically disfiguring cranio-facial tumours. ResultsThere were 6 females, and 2 male patients respectively, with an age range between 28 and 74years. The histological diagnoses were meningioma, frontal squamous cell carcinoma, fibrous dysplasia, frontal mucocoele, cemeto-ossifying fibroma, osteoma, and naso-ethmoidal squamous cell carcinoma. The patient with naso-ethmoidal squamous cell carcinoma had post-operative subgaleal empyema which was amenable to incision and drainage procedure. The patient with a frontal cemento-ossifyng fibroma had a transient immediate post-operative mechanical ptosis, which resolved completely in 3months. All of the total eight patients (100%) had satisfactory cosmetic outlook at a minimum follow up period of 1month post-operatively (Numeric Rating Scale of at least 7/10). One of the patients required a revision surgery on account of implant displacement. ConclusionCranioplasty is a common reconstructive neurosurgical procedure. It is important to the neurosurgeon for its neuro-protective function, and in the restoration of intra-cranial CSF dynamics. However, the cosmetic outlook appears to be more important to patients in the absence of pain and/or neurological deficits. Titanium mesh reconstruction is commonly used globally, and is becoming the preferred choice in low resource settings.

Compliance With Federal Price Transparency Rules and Cost Estimation at United States Hospitals With Neurosurgical Training Programs.

The Centers for Medicare & Medicaid Services implemented federal requirements on January 1, 2021, under the Public Health Service Act that require hospitals to provide a list of payer-negotiated prices or "standard charges" in a machine-readable file and in a patient-friendly online estimator for standard services. We sought to assess compliance by United States hospitals associated with neurosurgical training programs with these federal requirements for 11 common neurosurgical procedures. We performed a cross-sectional analysis in March 2023 of 116 United States hospitals associated with a neurosurgical training program to assess compliance with the new federal requirements to have a machine-readable, downloadable file with standard charges and a patient-friendly online estimator for two spinal procedures. A total of 110/114 (96.5%) hospitals were compliant with the requirement for a machine-readable file with payer-negotiated prices. A total of 47/110 hospitals (42.7%) were compliant with downloadable machine-readable files and reported at least one payer-negotiated price for 1 of the 11 common neurosurgical procedures. A total of 45/110 (40.9%) used bundled Diagnosis-Related Group codes, and 18/110 (16.4%) did not contain any price information for neurosurgical procedures. For neurosurgical procedures, the percent difference between the average negotiated private insurance and Medicare price per procedure ranged from 17.5% to 77.6%. Medicare and private insurance data for each procedure were available on average for 10.3 states (SD = 3.8) and 15.6 states (SD = 4.8), respectively. While hospital compliance with federal requirements for machine-readable files with payer-negotiated prices was high, availability of payer-negotiated prices for 4 major insurance types across 11 common neurosurgical procedures based on Current Procedural Terminology codes was sparce. Consequently, meaningful conclusions on procedure-related charges for elective procedures are difficult for patients to make because of the unintelligible format of data and a lack of reporting of charges per Current Procedural Terminology code in a comprehensive manner.

Association Between Race and Short-Term Outcomes Across 3988 Consecutive Single-Level Spinal Fusions

BACKGROUND AND OBJECTIVES: Race has implications for access to medical care. However, the impact of race, after access to care has been attained, remains poorly understood. The objective of this study was to isolate the relationship between race and short-term outcomes across patients undergoing a single, common neurosurgical procedure. METHODS: In this retrospective cohort study, 3988 consecutive patients undergoing single-level, posterior-only open lumbar fusion at a single, multihospital, academic medical center were enrolled over a 6-year period. Among them, 3406 patients self-identified as White, and 582 patients self-identified as Black. Outcome disparities between all White patients vs all Black patients were estimated using logistic regression. Subsequently, coarsened exact matching controlled for outcome-mitigating factors; White and Black patients were exact-matched 1:1 on key demographic and health characteristics (matched n = 1018). Primary outcomes included 30-day and 90-day hospital readmissions, emergency department (ED) visits, reoperations, mortality, discharge disposition, and intraoperative complication. RESULTS: Before matching, Black patients experienced increased rate of nonhome discharge, readmissions, ED visits, and reoperations (all P &lt; .001). After exact matching, Black patients were less likely to be discharged to home (odds ratio [OR] 2.68, P &lt; .001) and had higher risk of 30-day and 90-day readmissions (OR 2.24, P &lt; .001; OR 1.91, P &lt; .001; respectively) and ED visits (OR 1.79, P = .017; OR 2.09, P &lt; .001). Black patients did not experience greater risk of intraoperative complication (unintentional durotomy). CONCLUSION: Between otherwise homogenous spinal fusion cohorts, Black patients experienced unfavorable short-term outcomes. These disparities were not explained by differences in intraoperative complications. Further investigation must characterize and mitigate institutional and societal factors that contribute to outcome disparities.

Exploring complications following cranioplasty after decompressive hemicraniectomy: A retrospective bicenter assessment of autologous, PMMA and CAD implants

Cranioplasty (CP) after decompressive hemicraniectomy (DHC) is a common neurosurgical procedure with a high complication rate. The best material for the repair of large cranial defects is unclear. The aim of this study was to evaluate different implant materials regarding surgery related complications after CP. Type of materials include the autologous bone flap (ABF), polymethylmethacrylate (PMMA), calcium phosphate reinforced with titanium mesh (CaP-Ti), polyetheretherketone (PEEK) and hydroxyapatite (HA). A retrospective, descriptive, observational bicenter study was performed, medical data of all patients who underwent CP after DHC between January 1st, 2016 and December 31st, 2022 were analyzed. Follow-up was until December 31st, 2023. 139 consecutive patients with a median age of 54 years who received either PMMA (56/139; 40.3%), PEEK (35/139; 25.2%), CaP-Ti (21/139; 15.1%), ABF (25/139; 18.0%) or HA (2/139; 1.4%) cranial implant after DHC were included in the study. Median time from DHC to CP was 117 days and median follow-up period was 43 months. Surgical site infection was the most frequent surgery-related complication (13.7%; 19/139). PEEK implants were mostly affected (28.6%; 10/35), followed by ABF (20%; 5/25), CaP-Ti implants (9.5%; 2/21) and PMMA implants (1.7%, 1/56). Explantation was necessary for 9 PEEK implants (25.7%; 9/35), 6 ABFs (24.0%; 6/25), 3 CaP-Ti implants (14.3%; 3/21) and 4 PMMA implants (7.1%; 4/56). Besides infection, a postoperative hematoma was the most common cause. Median surgical time was 106 min, neither longer surgical time nor use of anticoagulation were significantly related to higher infection rates (p = 0.547; p = 0.152 respectively). Ventriculoperitoneal shunt implantation prior to CP was noted in 33.8% (47/139) and not significantly associated with surgical related complications. Perioperative lumbar drainage, due to bulging brain, inserted in 38 patients (27.3%; 38/139) before surgery was protective when it comes to explantation of the implant (p = 0.035). Based on our results, CP is still related to a relatively high number of infections and further complications. Implant material seems to have a high effect on postoperative infections, since surgical time, anticoagulation therapy and hydrocephalus did not show a statistically significant effect on postoperative complications in this study. PEEK implants and ABFs seem to possess higher risk of postoperative infection. More biocompatible implants such as CaP-Ti might be beneficial. Further, prospective studies are necessary to answer this question.

Can Publicly Available Artificial Intelligence Successfully Identify Current Procedural Terminology Codes for Common Procedures in Neurosurgery?

ObjectiveCoding for Neurosurgical procedures is a complex process that is dynamically changing year to year, through the annual introduction and removal of codes and modifiers. The authors hoped to elucidate if publicly available artificial intelligence (AI) could offer solutions for neurosurgeons in regards to coding. MethodsMultiple publicly available AI were asked to provide Current Procedural Terminology (CPT) codes and Revenue Value Units (RVU) values for common neurosurgical procedures of the brain and spine with a given indication for the procedure. The responses of platforms were recorded and compared to the currently valid CPT codes used for the procedure and the amount of RVUs that would be gained. ResultsSix platforms and Google were asked for the appropriate CPT codes for ten endovascular, spinal and cranial procedures each. The highest performing platforms were as follows: Perplexity.AI identified 70% of endovascular, BingAI identified 55% of spinal, and Chat GPT 4.0 with Bing identified 75% of cranial CPT codes. In regard to RVUs, the top performer gained 78% of endovascular, 42% of spinal, and 70% of cranial possible RVUs. In regard to accuracy, AI platforms on average outperformed Google (45% v. 25%, p=0.04236). ConclusionsThe ability of publicly available AIs to successfully code for neurosurgical procedures holds great promise in the future. Future development of AI should focus on improving accuracy in regard to CPT codes and provide supporting documentation for its decisions. Improvement on the existing capabilities of AI platforms can allow for increased operational efficiency and cost savings for practices.

IMAGINER: improving accuracy with a mixed reality navigation system during placement of external ventricular drains. A feasibility study.

The placement of a ventricular catheter, that is, an external ventricular drain (EVD), is a common and essential neurosurgical procedure. In addition, it is one of the first procedures performed by inexperienced neurosurgeons. With or without surgical experience, the placement of an EVD according to anatomical landmarks only can be difficult, with the potential risk for inaccurate catheter placement. Repeated corrections can lead to avoidable complications. The use of mixed reality could be a helpful guide and improve the accuracy of drain placement, especially in patients with acute pathology leading to the displacement of anatomical structures. Using a human cadaveric model in this feasibility study, the authors aimed to evaluate the accuracy of EVD placement by comparing two techniques: mixed reality and freehand placement. Twenty medical students performed the EVD placement procedure with a Cushing's ventricular cannula on the right and left sides of the ventricular system. The cannula was placed according to landmarks on one side and with the assistance of mixed reality (Microsoft HoloLens 2) on the other side. With mixed reality, a planned trajectory was displayed in the field of view that guides the placement of the cannula. Subsequently, the actual position of the cannula was assessed with the help of a CT scan with a 1-mm slice thickness. The bony structure as well as the left and right cannula positions were registered to the CT scan with the planned target point before the placement procedure. CloudCompare software was applied for registration and evaluation of accuracy. EVD placement using mixed reality was easily performed by all medical students. The predefined target point (inside the lateral ventricle) was reached with both techniques. However, the scattering radius of the target point reached through the use of mixed reality (12 mm) was reduced by more than 54% compared with the puncture without mixed reality (26 mm), which represents a doubling of the puncture accuracy. This feasibility study specifically showed that the integration and use of mixed reality helps to achieve more than double the accuracy in the placement of ventricular catheters. Because of the easy availability of these new tools and their intuitive handling, we see great potential for mixed reality to improve accuracy.

Complete Intraventricular Migration of Ventriculoperitoneal Shunt: Once in a Blue Moon Phenomenon of Shunt Surgery

AbstractShunt surgery is a very common neurosurgical procedure for hydrocephalus. It is associated with numerous complications, and intraventricular shunt migration is one of rarest. Various mechanisms have been described to explain this rare entity. Hereby we present an index case of this rare complication of shunt surgery in which patient presented with tuberculous meningitis with hydrocephalus having intraventricular shunt migration and will discuss possible mechanisms responsible for it. A 1-year old male infant, previously diagnosed case of tuberculous meningitis with hydrocephalus with right-sided ventriculoperitoneal shunt in situ, presented to the emergency department with bulging fontanelles secondary to shunt malfunction. Left-sided ventriculoperitoneal shunt was inserted. After few months, patient turned up again with left-sided shunt malfunction and right-sided intraventricular migrated shunt. Endoscopy-assisted removal of intraventricular migrated shunt and simultaneous third ventriculostomy was done. Patient improved in postoperative period. Being an extremely uncommon complication, intraventricular migration of shunt described as “once in a blue moon” phenomenon. It can be avoided by proper surgical technique with adequate-sized burr hole. Removal of shunt is preferred for prevention of infection.

Patient perception and satisfaction in awake burr hole trepanation under local anesthesia for evacuation of chronic subdural hematoma

Evacuation of chronic subdural hematoma (CSDH) will be one of the most common neurosurgical procedures in the future in the increasingly aging societies. Performing cranial surgery on awake patients may place a psychological burden on them. Aim of this study was to evaluate the psychological distress of patients during awake CSDH relief. Patients with awake evacuation of CSDH via burr hole trepanation were included in our monocentric prospective study. Patient perception and satisfaction were measured using standardized surveys 3–5 days and 6 months after surgery. Among other questionnaires, the Hospital Anxiety and Depression and the Impact of Event Scale, were used to quantify patients' stress. A total of 50 patients (mean age 72.9 years (range 51 – 92)) were included. During surgery, 28 patients reported pain (mean 4.1 (SD 3.3)). Postoperatively, 26 patients experienced pain (mean 2.7 (SD 2.6)). Patients’ satisfaction with intraoperative communication was reported with a mean of 8.3 (SD 2.1). There was a significant negative correlation between intraoperatively perceived pain and satisfaction with intraoperative communication (p = 0.023). Good intraoperative communication during evacuation of CSDH in awake patients is associated with positive patient perception and correlates with pain reduction.

The Neurosurgeon's Dilemma—Do Antiplatelet/Anticoagulant Medications Increase the Risk of Catheter-Associated Hemorrhage in External Ventricular Drain Placement?

IntroductionExternal ventricular drain (EVD) placement is a common neurosurgical procedure that can be performed at bedside. A frequent complication following EVD placement is catheter-associated hemorrhage (CAH). The hemorrhage itself is rarely clinically significant but may be complicated in patients taking anticoagulant or antiplatelet (AC/AP) medications. MethodsA total of 757 patients were who underwent EVD placement at bedside were included as part of a retrospective study at a large academic medical center. Demographic factors, use of AC/AP therapies, and several other clinical variables were recorded and assessed in univariate and multivariate regression analysis for association with CAH and mortality. ResultsOne hundred (13.2%) patients experienced CAH within 24 hours of the procedure. After univariate analysis, in two tandem-run multivariate regression analyses after stepwise variable selection, use of two or more AC/AP agents (OR=2.362, p=0.020) and dual antiplatelet therapy with aspirin and clopidogrel (OR=3.72, p=0.009) were significantly associated with CAH. Use of non-coated catheters was a protective factor against CAH compared to use of antibiotic-coated catheters (OR=0.55, p=0.019). Multivariate analysis showed age, multi-agent therapy, and thrombocytopenia were significantly associated with increased mortality. ConclusionThere was increased risk of CAH after EVD placement in patients taking more than one AC/AP agent regardless of presenting pathology. In particular, use of aspirin and clopidogrel combined was associated with significantly higher odds of CAH, although it was not associated with higher mortality. In addition, there appears to be an association between use of antibiotic-coated catheters and CAH across univariate and multivariate analysis.

Iatrogenic Cerebrospinal Fluid Breast Augmentation: Rare Complication of Ventriculoperitoneal Shunts and Management Strategies

BackgroundVentriculoperitoneal shunt is one of the most common neurosurgical procedures in the treatment of hydrocephalus. There are reports of migration of the distal catheter to the breast pocket where cerebrospinal fluid then collects and can develop into a pseudocyst. There exist case reports in the literature of patients with prior breast augmentation who present with distal catheter migration from the peritoneal space into the breast tissue. We present a case series of three patients with pre-existing breast augmentation who returned with unilateral breast enlargement after ventriculoperitoneal shunt. In all three patients, the distal catheter migrated out of the peritoneal space and was found to be coiled around the breast prosthesis. Additionally, we offer recommendations for managing these complications and a review of the literature. MethodsWe performed a systematic review without meta-analysis of studies involving management of shunt migration in the setting of pre-existing breast implants. We present a case series of three patients who we treated with breast cerebrospinal pseudocyst after migration of the distal catheter into the breast tissue. ResultsA total of 17 studies, dating from 2002 to 2022, met our inclusion and exclusion criteria and were selected for full review. Catheter migration occurred between two weeks and 9 months of initial shunt placement. All patients presented with unilateral breast enlargement and CSF pseudocyst formation. All patients underwent revision shunt surgery. Surgical treatment strategies utilized included re-implantation of the distal catheter into the pleural space or ipsilateral or contralateral peritoneal space or complete removal of the entire shunt system. ConclusionsBreast-related VPS complications is a rare entity that is increasingly seen as more patients receive breast augmentation. Breast related shunt complications most commonly present with CSF pseudocyst formation in the breast. It is important for neurosurgeons to be aware of an underlying breast implant prior to placing a VPS. For patients who have migration of the distal catheter into the breast, a protocol for managing these situations should be followed to ensure no shunt infection and avoidance of future catheter migration complications with subsequent shunt revisions.

Development of a test setup for hydrodynamic characterization of hydrocephalus shunts

Abstract Implantation of a shunt system is the most common neurosurgical procedure for the treatment of hydrocephalus. Hydrodynamic parameters of hydrocephalus shunt systems are valuable variables to address patients' needs. In this report, we present a test setup to evaluate hydrodynamic parameters of hydrocephalus shunt systems. The test setup was validated using a stainless steel capillary and compared with the analytical solution according to Bernoulli's equation. It was demonstrated that the experimental setup is able to model the pressure in a physiologically relevant range. The measured and averaged flow resistance was 2.96 mmHg/(ml min-1). According to the analytical solution of Bernoulli's equation, the flow resistance is 2.86 mmHg/(ml min-1). Therefore, the measured flow resistance is 3.5% higher than the analytical solution. Moreover, the nonlinear characteristic of the pressure drop at the inlet and outlet of the capillary plays a minor role compared to the friction of the tube flow. As a result, the increase in flow rate with increasing pressure load can be well approximated by a linear function for the low flow rates measured here. The experimental setup presented will be used in the future to characterize commercially available shunt systems under various hydrodynamic conditions.