Intracranial Neurosurgery Research Articles

Vacuum Sealing Drainage against Surgical Site Infection after Intracranial Neurosurgery.

Background: Surgical site infections (SSIs) remain a conundrum for neurosurgeons. This study examines the efficacy and outcome of vacuum sealing drainage (VSD) in the treatment of pyogenic SSIs following intracranial neurosurgery. Methods: Twenty patients with SSIs, who received surgical intervention, were treated retrospectively with VSD during the past five years. Primary surgical procedure types, SSI types, VSD replacements, pathogenic germs, antibiotic therapy, and infection control were reviewed and discussed. Results: Of the 20 infections, 13 (65%) were extradural and 7 (35%) were extradural SSIs combined with intracranial infections (including 5 meningitis, 1 subdural abscess, and 1 brain abscess). All the patients consented to medical device implantation (including 5 titanium webs, 6 bone flap fixation devices, and 12 duraplasties), most of which were removed during debridement. The median duration from primary surgical procedure to an SSI diagnosis was 19 days (range: 7 to 365 d). All the patients also agreed to debridement and VSD treatment; VSD was replaced 0 to 5 times (median, one time) every 4 to 7 days and kept for 4 to 35 days (median, 14 d). Seven (35%) patients had defined bacterial infections, with Staphylococcus aureus being the dominant infection. The deployed standard VSD and antibiotic treatment ensured full recovery from SSIs, including from intracranial infections: 14 (70%) patients had recovered fully by follow-up, and no infection-associated death was registered; 6 (30%) patients died of severe primary affections. Conclusion: VSD-assisted therapy is safe and effective against SSIs after intracranial neurosurgery.

Incidence and Characteristics of Surgical Side Infections in Patients Undergoing Intracranial Neurosurgery for Vascular Pathologies

Incidence and Characteristics of Surgical Side Infections in Patients Undergoing Intracranial Neurosurgery for Vascular Pathologies

Alfred Washington Adson: Perspectives on Intracranial Neurosurgery and the Responsibilities of the Neurosurgeon.

In a period when the budding field of neurosurgery was believed to have little promise, Dr Alfred Washington Adson founded and led the first neurosurgical department at Mayo Clinic. He was not without reservations-surgical intervention for neurological conditions was rarely pursued because of poor outcomes and high complication rates, and Dr Adson acknowledged his early concerns about the future of neurosurgery in his memoirs. However, his education, mentorship, his training, and his first neurosurgical cases helped to shape the impact he ultimately had on the field and his legacy as a neurosurgeon. Dr Adson trained with several renowned Mayo general surgeons, notably his mentor Dr Emil Beckman, whose desire for operative precision shaped Dr Adson's drive to develop his own skills as a surgeon. Two years into his residency, he became the youngest staff surgeon and was tasked with managing the neurosurgical cases at Mayo. The five neurosurgical cases overseen by Dr Adson in the next year illuminated the opportunity for neurosurgery to drastically improve the lives of patients. Dr Adson, given the option of continuing as either a general surgeon or a neurosurgeon, ultimately chose to pursue neurosurgery. This article seeks to provide a historical perspective on the neurosurgeon Dr Alfred Washington Adson using primary and secondary accounts from the Mayo archives, highlighting his contributions to the early understanding of intracranial pathology and how his early experiences as a trainee developed into a personal passion for self-improvement, education, and advocacy for health care in America.

A Novel Portable, Mobile MRI: Comparison with an Established Low-Field Intraoperative MRI System.

Background MRI (magnetic resonance imaging) using low-magnet field strength has unique advantages for intraoperative use. We compared a novel, compact, portable MR imaging system to an established intraoperative 0.15 T system to assess potential utility in intracranial neurosurgery. Methods Brain images were acquired with a 0.15 T intraoperative MRI (iMRI) system and a 0.064 T portable MR system. Five healthy volunteers were scanned. Individual sequences were rated on a 5-point (1 to 5) scale for six categories: contrast, resolution, coverage, noise, artifacts, and geometry. Results Overall, the 0.064 T images (M = 3.4, SD = 0.1) had statistically higher ratings than the 0.15 T images (M = 2.4, SD = 0.2) ( p < 0.01). All comparable sequences (T1, T2, T2 FLAIR and SSFP) were rated significantly higher on the 0.064 T and were rated 1.2 points (SD = 0.3) higher than 0.15 T scanner, with the T2 fluid-attenuated inversion recovery (FLAIR) sequences showing the largest increment on the 0.064 T with an average rating difference of 1.5 points (SD = 0.2). Scanning time for the 0.064 T system obtained images more quickly and encompassed a larger field of view than the 0.15 T system. Conclusions A novel, portable 0.064 T self-shielding MRI system under ideal conditions provided images of comparable quality or better and faster acquisition times than those provided by the already well-established 0.15 T iMR system. These results suggest that the 0.064 T MRI has the potential to be adapted for intraoperative use for intracranial neurosurgery.

Incidence, predictors, and impact of acute post-operative pain after cranial neurosurgery: A prospective cohort study.

Pain is common after craniotomy. Its incidence and predictors in developing nations are not adequately studied. We aimed to assess the incidence, predictors, and impact of acute post-operative pain after intracranial neurosurgeries. This prospective observational study was conducted in adult patients undergoing intracranial neurosurgeries. After patient consent, ethics committee approval, and study registration, we assessed the incidence of post-operative pain using numerical rating scale (NRS) score. Predictors and impact of pain on patient outcomes were also evaluated. A total of 497 patients were recruited during 10-month study period. Significant (4-10 NRS score) post-operative pain at any time-point during the first 3 days after intracranial neurosurgery was reported by 65.5% (307/469) of patients. Incidence of significant pain during the 1st post-operative h, on the 1st, 2nd, and 3rd post-operative days was 20% (78/391), 50% (209/418), 38% (152/401), and 24% (86/360), respectively. Higher pre-operative NRS score and pain during the 1st h post-operatively, predicted the occurrence of pain during the first 3 days after surgery, P = 0.003 and P < 0.001, respectively. Pain was significantly associated with poor sleep quality on the first 2 post-operative nights (P < 0.001). Patient satisfaction score was higher in patients with post-operative pain, P = 0.002. Every two in three patients undergoing elective intracranial neurosurgery report significant pain at some point during the first 3 postoperative days. Pre-operative pain and pain during 1st post-operative h predict the occurrence of significant post-operative pain.

Direct-cortical visual evoked potential monitoring during brain tumor resection

BackgroundVisual evoked potential (VEP) recording is traditionally regarded as an unreliable evoked potential monitoring technique, precluding widespread use in intracranial neurosurgery. However, VEPs can serve as a useful intraoperative adjunct for real-time detection of mechanical damage to optic apparatuses. The low obtainability and prognostic utility of VEPs are associated with transcranial recording, which typically provides non-focal information and poor signal-to-noise ratio. Direct cortical VEP (DC-VEP) recordings may offer a solution. MethodsWe evaluated the obtainability of DC-VEPs as well as their prognostic utility in predicting postoperative visual function deterioration in a series of brain tumor patients undergoing craniotomies for tumor resection. Patient records were retrospectively reviewed for all consecutive patients undergoing brain tumor resections with DC-VEP monitoring. Pre- and postoperative visual fields were characterized from patient charts and associated with the presence of intraoperative monitoring alerts to determine the sensitivity, specificity, and positive and negative predictive values (PPV, NPV) of DC-VEPs in detecting postoperative visual field deficits. ResultsTwenty-two patients (9 male, 13 female) were included, with a median age of 60 years. DC-VEPs were reliably detected in 19 of 23 included surgeries (82.6%). The reported sensitivity, specificity, PPV, and NPV in detecting postoperative visual field deficits was 60%, 92.9%, 75%, and 86.7%, respectively. There was a statistically significant association between monitoring alerts and the presence of visual field deterioration by Fischer’s exact test (p = 0.0374). ConclusionsDC-VEPs can be reliably obtained and are useful for detecting mechanical injury to optic areas and tracts during tumor resection.

Perioperative care practices and outcomes of intracranial neurosurgery: Experience at a dedicated neurosciences hospital in a developing country.

Understanding of perioperative care practices and early postoperative outcomes helps minimize potentially preventable perioperative complications while supporting systemic and neurological well-being. The objective of this prospective study was to evaluate the perioperative care practices and early postoperative outcomes of cranial neurosurgery at a high-volume tertiary care neurosciences hospital in India. We also aimed to see if the care elements differed depending on the surgical approach. We hypothesized that care elements and outcomes are likely to be different between major surgical approaches. This was a prospective observational study of consecutive adult neurosurgical patients who underwent elective surgeries for intracranial pathologies over a period of six months from October 2020 to March 2021 at a tertiary care neurosciences center in India. Perioperative data about intraoperative care elements and early postoperative outcomes till the third day after surgery were collected. Incidence of blood loss >1 L was significantly (P = 0.07) higher after infratentorial surgery (26%, N = 17). Incidence of intraoperative and postoperative desaturation was more after transnasal surgery (6%, N = 2, P = 0.002, and 9%, N = 3, P = 0.01, respectively). This study informs the early perioperative care practices of neurosurgical patients from a dedicated neurosciences hospital in a developing world. We observed that transnasal surgery was associated with more perioperative adverse events and slower convalescence compared to supra- and infratentorial surgeries despite being a considerably less invasive surgery.

Postoperative delirium after intracranial neurosurgery: A prospective cohort study from a developing nation.

Post-operative delirium (POD) is a major complication after anesthesia and surgery with an incidence varying from 5 to 50%. The incidence of POD after intracranial surgery is likely to be higher due to the pre-existing brain pathology and direct handling of the brain during neurosurgery. The primary objective of this study was to assess the incidence of POD after intracranial neurosurgery and our secondary objective was to identify the potential risk factors for its occurrence. This prospective observational study was conducted after the institutional ethics committee approval between october 2020 and march 2021. We included patients of either gender aged ≥ 18 years and undergoing elective intracranial neurosurgery. Exclusion criteria included patients aged below 18 years, undergoing emergency neurosurgery, patients with impaired consciousness and patients with psychiatric comorbidities or those taking psychotropic medications. We planned to exclude patients from analysis who were transferred to intensive care unit (ICU) or if they were not extubated after surgery. Our study outcome was development of POD as assessed by confusion assessment method (CAM). The overall incidence of POD during the three postoperative days was 19.2% (n=60/313). The incidence of POD on days 1, 2, and 3 were 19.2% (n=60/313), 17.2% (n=50/291), and 16.3% (n=39/239). Preoperative delirium and hyperactive Emergence Delirium were found to be the significant predictors of POD. Every one in five patients undergoing intracranial neurosurgery is vulnerable for the development of POD within first three days after surgery. The incidence of occurrence of POD is time-sensitive and is decremental.

Goal-Directed Fluid Therapy and major postoperative complications in elective craniotomy. A retrospective analysis of a before-after multicentric study

BackgroundGoal-Directed Fluid Therapy (GDFT) is recommended to decrease major postoperative complications. However, data are lacking in intra-cranial neurosurgery.MethodsWe evaluated the efficacy of a GDFT protocol in a before/after multi-centre study in patients undergoing elective intra-cranial surgery for brain tumour. Data were collected during 6 months in each period (before/after). GDFT was performed in high-risk patients: ASA score III/IV and/or preoperative Glasgow Coma Score (GCS) < 15 and/or history of brain tumour surgery and/or tumour greater size ≥ 35 mm and/or mid-line shift ≥ 3 mm and/or significant haemorrhagic risk. Major postoperative complication was a composite endpoint: re-intubation after surgery, a new onset of GCS < 15 after surgery, focal motor deficit, agitation, seizures, intra-cranial haemorrhage, stroke, intra-cranial hypertension, hospital-acquired related pneumonia, surgical site infection, cardiac arrythmia, invasive mechanical ventilation ≥ 48 h and in-hospital mortality.ResultsFrom July 2018 to January 2021, 344 patients were included in 3 centers: 171 in the before and 173 in the after (GDFT) period. Thirty-six (21.1%) patients displayed a major postoperative complication in the Before period, and 50 (28.9%) in the After period (p = 0.1). In the propensity score analysis, we matched 48 patients in each period: 9 (18.8%) patients in the After period and 14 (29.2%) patients in the Before period displayed a major perioperative complication (p = 0.2). Sixty-two (35.8%) patients received GDFT in the After period, with great heterogeneity among centers (p < 0.05).ConclusionsIn our before-after study, GDFT was not associated with a decrease in postoperative major complications in elective intra-cranial neurosurgery.

Effect of sevoflurane versus desflurane on blood glucose level in patients undergoing intracranial neurosurgery: A randomised controlled study.

Anaesthetic agents can affect the neuroendocrine response to surgical stress. Along with affecting other parameters, this can affect blood glucose levels. This study aimed to compare the effect of sevoflurane and desflurane on hourly intraoperative blood glucose levels in non-diabetic patients undergoing intracranial surgery. A total of 70 adults (18-65 years) of American Society of Anesthesiologists physical status I and II undergoing elective intracranial surgery for supratentorial and infratentorial lesions were enroled. Patients were randomised to receive either sevoflurane or desflurane as the maintenance anaesthetic agent. The blood glucose level was measured hourly after induction until the completion of surgery. Parametric tests, non-parametric tests, Friedman test, generalised estimating equations, Chi-square test, and Fisher's exact test were used to analyse the data. In the sevoflurane group, the mean (standard deviation) blood glucose (mg/dL) increased from 93.34 (9.33) at the baseline to a maximum of 102.00 (8.61) at the 9 hours timepoint. This change was statistically significant (P < 0.001). In the desflurane group, the mean blood sugar (mg/dL) increased from 89.34 (9.85) at the baseline to a maximum of 92.37 (9.92) at the 4 hours timepoint and then decreased to 88.50 (0.71) at 9 hours timepoint. Desflurane caused an initial rise followed by a decline, whereas a gradual increase in intraoperative blood glucose level was seen with sevoflurane use in non-diabetic adult patients undergoing elective neurosurgery. The intraoperative change in blood sugar was statistically significant but was within the normal clinical range.

The Scanning Fiber Endoscope: A Novel Surgical and High-Resolution Imaging Device for Intracranial Neurosurgery.

The scanning fiber endoscope (SFE) is a novel medical imaging device that has been used in various vascular beds as a form of angioscopy, as well as in tracts and duct systems for endoluminal imaging. Owing to its miniaturized form, high resolution, and flexibility, it has demonstrated success in imaging across a wide range of diagnostic applications. To demonstrate, by performing a third ventriculostomy and visualizing the cranial nerves and brainstem anatomy, that, without modification, the SFE can be used through a transcranial approach in a therapeutic intraventricular neurosurgical application. A 3.7 French SFE system was used without modification on a live porcine model to perform a third ventriculostomy and acquire high-resolution images of the animal's ventricular system, cranial nerves, and brainstem. A side-by-side comparison was made with one of the current standard-of-care rigid endoscopes as a context for size and image quality. High-resolution video-rate imaging was used to assist the successful, uncomplicated performance of a third ventriculostomy. High-resolution endoscopic images of the brainstem and cranial nerves were acquired. Although the SFE has been shown to be a superior device for imaging, here we demonstrate its first use as a potential therapeutic device in intracranial neurosurgery.

Emergence delirium after intracranial neurosurgery- a prospective cohort study

ObjectivesThe primary objective of this study was to estimate the incidence of emergence delirium (ED) including hypo- and hyperactive ED, after intracranial neurosurgery. Secondary objective was to identify perioperative risk factors of ED in these patients. MethodsThis prospective observational study was conducted at an academic neurosciences hospital. All consecutive adult patients (age ≥ 18 years) with a preoperative Glasgow Coma Scale score of 15 undergoing elective intracranial surgery under general anesthesia during the six-month period from October 2020 to March 2021 were included in this study. Perioperative patient data were collected till one hour after surgery. ED was defined as per Riker’s sedation agitation score (SAS) as hyperactive ED when SAS was >4 and hypo active ED when SAS was <4 on a 1 to 7 scale. ResultsData of 320 patients were analyzed in this study. The overall incidence of ED was 22 % (71/320), with incidence of hyperactive ED of 4.3 % (n = 14) and hypoactive ED of 18 % (n = 57). The risk factors for ED were preoperative delirium (odds ratio [OR], 95 % confidence interval [CI] and p value of 4.41, 1.3–15.19, and 0.002), education level (OR = 2.21, [0.98–4.94], p = 0.05), minimum alveolar concentration of inhalational anesthetic (OR = 1.47, [1.17–1.88], p = 0.002), postoperative nausea and vomiting (OR = 4.56, [2.04–10.32], p = 0.001), and body weight (OR = 1.69, [1.1–2.68], p = 0.02). Hyperactive ED was predicted by preoperative delirium (OR = 5.28, [1.12–21.21], p = 0.024) and low education level (OR = 4.35, [1.2–17.04], p = 0.027). ConclusionsAtleast one in five patients undergoing brain surgery under anesthesia develop ED. Addressing modifiable risk factors might reduce ED.

Emergence Delirium after Intracranial Neurosurgery- a Prospective Cohort Study

Emergence Delirium after Intracranial Neurosurgery- a Prospective Cohort Study

Deformable MR-CT image registration using an unsupervised, dual-channel network for neurosurgical guidance.

The accuracy of minimally invasive, intracranial neurosurgery can be challenged by deformation of brain tissue - e.g., up to 10mm due to egress of cerebrospinal fluid during neuroendoscopic approach. We report an unsupervised, deep learning-based registration framework to resolve such deformations between preoperative MR and intraoperative CT with fast runtime for neurosurgical guidance. The framework incorporates subnetworks for MR and CT image synthesis with a dual-channel registration subnetwork (with synthesis uncertainty providing spatially varying weights on the dual-channel loss) to estimate a diffeomorphic deformation field from both the MR and CT channels. An end-to-end training is proposed that jointly optimizes both the synthesis and registration subnetworks. The proposed framework was investigated using three datasets: (1) paired MR/CT with simulated deformations; (2) paired MR/CT with real deformations; and (3) a neurosurgery dataset with real deformation. Two state-of-the-art methods (Symmetric Normalization and VoxelMorph) were implemented as a basis of comparison, and variations in the proposed dual-channel network were investigated, including single-channel registration, fusion without uncertainty weighting, and conventional sequential training of the synthesis and registration subnetworks. The proposed method achieved: (1) Dice coefficient=0.82±0.07 and TRE=1.2±0.6mm on paired MR/CT with simulated deformations; (2) Dice coefficient=0.83±0.07 and TRE=1.4±0.7mm on paired MR/CT with real deformations; and (3) Dice=0.79±0.13 and TRE=1.6±1.0mm on the neurosurgery dataset with real deformations. The dual-channel registration with uncertainty weighting demonstrated superior performance (e.g., TRE=1.2±0.6mm) compared to single-channel registration (TRE=1.6±1.0mm, p<0.05 for CT channel and TRE=1.3±0.7mm for MR channel) and dual-channel registration without uncertainty weighting (TRE=1.4±0.8mm, p<0.05). End-to-end training of the synthesis and registration subnetworks also improved performance compared to the conventional sequential training strategy (TRE=1.3±0.6mm). Registration runtime with the proposed network was ∼3s. The deformable registration framework based on dual-channel MR/CT registration with spatially varying weights and end-to-end training achieved geometric accuracy and runtime that was superior to state-of-the-art baseline methods and various ablations of the proposed network. The accuracy and runtime of the method may be compatible with the requirements of high-precision neurosurgery.

Cerebral Arteriovenous Malformations Treated With Linear Accelerator Stereotactic Radiosurgery Guided by Magnetic Resonance Imaging and Panangiography: A Latin American Experience

Cerebral arteriovenous malformations (AVM) are vascular lesions that include aberrant communication between arterial and venous systems. Treatment for AVM is still under debate. Surgery, embolization, observation, and radiosurgery are options for patients. Most data for radiosurgery came from the Gammaknife series. However, low middle-income countries have financial constraints to establish dedicated intracranial neurosurgery machines. We aimed to determine AVM obliteration rate in patients treated with linear accelerator stereotactic radiosurgery (SRS) guided by magnetic resonance imaging and panangiography fusion with computed tomography simulation at a quaternary care institution in Latin America.We conducted an observational study with patients treated with SRS at our institution during 2011 and 2017. Exclusion criteria were age younger than 14 and a history of brain cancer. After IRB approval, data were collected retrospectively by reviewing medical records. Patients without available follow-up were contacted to gather missing information. Primary outcome was obliteration rate at 3 years, confirmed by diagnostic imaging (MRI or cerebral panangiography). Secondary outcomes were intracranial bleeding, headaches, epilepsy, and neurological deficits at clinical presentation and after SRS. Analysis included sociodemographic data, AVM characteristics (location and Spetzler-Martin grading), and treatment features. We used descriptive statistics, measures of central tendency and dispersion, and proportions.We included 85 patients. The mean age at treatment was 40.8 (14-73), 49.4% of patients were male, and 50.6% female. The most common location was the frontal lobe in 25.9% (n = 22) and the parietal lobe in 24.7% (n = 21). At diagnosis, 44% of patients had a history of intracranial hemorrhage. 49 patients had received previous embolization. The mean dose of radiosurgery was 19.3 Gy (14-25). The mean isodose was 95.25 (80-98). 35.3% of the patients had an AVM Spetzler-Martin grade 2, 40% grade 3, and 12.9% grade 4. We obtained long-term follow-up data for 42 patients, with a median follow-up of 1366 days. The overall obliteration rate was 60%, based primarily on panangiography (59.1%). Symptoms after SRS included headaches (n = 30) and seizures (n = 10). 2 patients presented intracranial bleeding. We contacted all missing patients, but no follow-up data was available for analysis. Most missing patients lived outside the city.Tri-modality image fusion SRS with linear accelerators for AVM could be a safe and accessible option in low-middle income countries. Health administrator issues, travel distances to access linear accelerators and multidisciplinary teams hinder timely follow-up and surveillance imaging. More prospective data are needed to define the role of SRS for AVMs.V. Rangel: None. J. Cure: None. M. Caicedo-Martinez: None. G. Borda: None. C. Lindado: None. E. Castro-Lombana: None. J. Puentes: None. O. Zorro: None. A. González-Motta: None.

Comparison of recovery profile between sevoflurane and isoflurane as volatile agents in neurosurgery in Indian population

Background: In most instances rapid emergence from general anesthesia after intracranial neurosurgery is desirable. The most compelling reason for this is the need for the patient to cooperate with a postoperative neurological examination intended to screen for such potential intracranial disaster as hematoma formation, herniation, and cerebrovascular accidents. Anesthetic techniques were adopted to achieve rapid emergence. In this respect, inhaled anesthetic agents have an important role in influencing the recovery time after anesthesia and surgery. The aim of this study is to compare isoflurane and sevoflurane as regard to speed of recovery from anesthesia and recovery of post-operative cognitive function in Indian populationMethods: The study was carried out as randomized control, blinded study of patients undergoing neurosurgery in tertiary care hospital. Sample sizes of 60 patients were studied. They were divided into two groups. Results: Sevoflurane shows faster emergence, extubation, motor control (in form of hand squeeze) and orientation time as compared to isoflurane. Though clinically the time difference for the various variables studied was 0.8 to 2.7 min only, statistically the results were significant and supported the basis for this difference as the difference in blood gas solubility coefficient between sevoflurane and isofluraneConclusions: Sevoflurane is recommended for use for faster extubation, emergence and post-operative neurological examination. The observation shows good brain relaxation with the use of both volatile anesthetic agents

Preoperative risk factors associated with new focal neurological deficit and other major adverse events in first-time intracranial meningioma neurosurgery

BackgroundNeurosurgical resection is the mainstay of meningioma treatment. Adverse event (AE) rates of meningioma resections are significant, but preoperative risk factors for major AEs in patients undergoing first-time meningioma surgery are largely unknown. The aim of this study was to explore major AEs and identify preoperative risk factors in patients undergoing first-time meningioma surgery.MethodsData on all meningioma resections performed at the University Hospital Zurich from 1 January 2013 to 31 December 2018 were collected in a prospective registry. All AEs that occurred within 3 months of surgery were documented in detail and classified as “minor” or “major.” Statistical analysis included initial individual bivariate analyses of all preoperative factors and the occurrence of major AEs. Statistically significant variables were then included in a logistic regression model to identify predictors.ResultsThree hundred forty-five patients were included in the study. Mean age was 58.1 years, and 77.1% of patients were female. The overall major AE rate was 20.6%; the most common of which was a new focal neurological deficit (12.8% of patients). Six preoperative factors showed a significant association with the occurrence of major AEs in bivariate analysis. All variables included in the logistic regression model showed increased odds of occurrence of major AE, but only tumor complexity as measured by the Milan Complexity Scale was a statistically significant predictor, with a score of 4 or more having twice the odds of major AEs (OR: 2.00, 95% CI: 1.15–3.48).ConclusionHigh tumor complexity is an independent predictor of the occurrence of major AEs following meningioma resection. Preoperative assessment of tumor complexity using the Milan Complexity Scale is warranted and can aid communication with patients about AE rates and surgical decision-making.

Status epilepticus after intracranial neurosurgery: incidence and risk stratification by perioperative clinical features.

Status epilepticus (SE) is associated with significant mortality, cost, and risk of future seizures. In one of the first studies of SE after neurosurgery, the authors assess the incidence, risk factors, and outcome of postneurosurgical SE (PNSE). Neurosurgical admissions from the MarketScan Claims and Encounters database (2007 through 2015) were assessed in a longitudinal cross-sectional sample of privately insured patients who underwent qualifying cranial procedures in the US and were older than 18 years of age. The incidence of early (in-hospital) and late (postdischarge readmission) SE and associated mortality was assessed. Procedural, pathological, demographic, and anatomical covariates parameterized multivariable logistic regression and Cox models. Multivariable logistic regression and Cox proportional hazards models were used to study the incidence of early and late PNSE. A risk-stratification simulation was performed, combining individual predictors into singular risk estimates. A total of 197,218 admissions (218,217 procedures) were identified. Early PNSE occurred during 637 (0.32%) of 197,218 admissions for cranial neurosurgical procedures. A total of 1045 (0.56%) cases of late PNSE were identified after 187,771 procedure admissions with nonhospice postdischarge follow-up. After correction for comorbidities, craniotomy for trauma, hematoma, or elevated intracranial pressure was associated with increased risk of early PNSE (adjusted OR [aOR] 1.538, 95% CI 1.183-1.999). Craniotomy for meningioma resection was associated with an increased risk of early PNSE compared with resection of metastases and parenchymal primary brain tumors (aOR 2.701, 95% CI 1.388-5.255). Craniotomies for infection or abscess (aHR 1.447, 95% CI 1.016-2.061) and CSF diversion (aHR 1.307, 95% CI 1.076-1.587) were associated with highest risk of late PNSE. Use of continuous electroencephalography in patients with early (p < 0.005) and late (p < 0.001) PNSE rose significantly over the study time period. The simulation regression model predicted that patients at high risk for early PNSE experienced a 1.10% event rate compared with those at low risk (0.07%). Similarly, patients predicted to be at highest risk for late PNSE were significantly more likely to eventually develop late PNSE than those at lowest risk (HR 54.16, 95% CI 24.99-104.80). Occurrence of early and late PNSE was associated with discrete neurosurgical pathologies and increased mortality. These data provide a framework for prospective validation of clinical and perioperative risk factors and indicate patients for heightened diagnostic suspicion of PNSE.

Electromagnetic Navigation Systems and Intraoperative Neuromonitoring: Reliability and Feasibility Study.

A recent influx of intraoperative technology is being used in neurosurgery, but few reports investigate the accuracy and safety of these technologies when used simultaneously. To assess the ability to use an electromagnetic navigation system alongside multimodal intraoperative neurophysiological monitoring (IONM). Single-institution prospective cohort study of patients requiring craniotomy for brain tumor resection operated using an electromagnetic navigation system (AxiEM, Medtronic®). motor evoked potentials, somatosensory evoked potentials (SSEPs), electroencephalography, and electromyography were recorded and analyzed with AxiEM on (with/without filters) and off. The neurological outcomes of the patients were recorded. A total of 15 patients were included (8 males/7 females, mean age 52.13 yr). Even though the raw acquisition is affected by the electromagnetic field (particularly SSEPs), no significant difference was detected in the morphology, amplitude, and latency of the different monitoring modalities (AxiEM off vs on) after the appropriate software filter application. Adjustments to the frequency of SSEP stimulation and number of averages, and reductions to the low-pass filters were applied. Notch filters were used appropriately and changes to the physical setup of the IONM and electromagnetic navigation system equipment reduced noise. Postoperatively, none of the patients developed new focal deficits; 7 patients showed improvement in their motor deficit (4 recovered fully). The information provided by the IONM in intracranial neurosurgery patients whilst also using electromagnetic navigation systems is reliable for monitoring, mapping, and detecting intraoperative complications, provided that the appropriate software filters and tools are applied.

Palonosetron versus ondansetron for prophylaxis of postoperative nausea and vomiting following craniotomy: A prospective randomized controlled trial

BackgroundPostoperative nausea and vomiting (PONV) is a common adverse event that may occur in as many as 80% of high-risk patients after general anesthesia. Intracranial neurosurgery, especially infratentorial type, is considered as an additional PONV risk factor. We performed our study to compare antiemetic efficacy of ondansetron versus palonosetron for prevention of PONV in patients undergoing elective neurosurgery for intracranial tumors remove. Methods80 patients 18 to 80 years of age with ASA physical status I or II underwent elective neurosurgery for intracranial tumor removal under general anesthesia were randomized into two groups in 1:1 ratio to receive ondansetron (8 mg) or palonosetron (0.075 mg). Each group included two equal subgroups based on the type of procedure: supratentorial and infratentorial. In both subgroups we provided IV anesthesia based on propofol. Both antiemetic drugs were given intravenously before closing the dura mater. In most patients dexamethasone 8 mg for PONV prevention was also used. Incidence of PONV in 48 hours period after surgery as primary outcome was evaluated. PONV scale was used for assessment at 30 min, 1, 2, 6, 12, 24, and 48 hours after extubation postoperatively. Patient-related risk factors for PONV, intervention characteristics, visual analog scale (VAS) pain scores at 30 min, 1, 2, 6, 12, 24, and 48 hours after extubation postoperatively, rate of rescue antiemetic drug use were also recorded. ResultsThe final analysis included 78 patients (38 in palonosetron group and 40 in ondansetron group). Palonosetron significantly decreased incidence of PONV in infratentorial subgroup of patients compared to ondansetron (70% vs. 28%, respectively; RR=0.40; 95% СI: 0.18-0.89). However, the difference was not statistically significant in the general cohort of study patients (26.3% vs. 45%, respectively; RR=0.58; 95% СI: 0.31-1.10). The administration of palonosetron was not associated with decreased use of rescue antiemetics in either the palonosetron or the ondansetron group (15.8% vs. 22.5%, respectively; p=0.57) nor in the infratentorial subgroup that received palonosetron compared to which received ondansetron (16.6% vs. 40%, respectively; p=0.159). ConclusionIntraoperative palonosetron was more effective than ondansetron for prevention of PONV in patients following infratentorial craniotomy. Risk reduction of PONV after craniotomy in general was insignificant.