Chameleons, red herrings, and false localizing signs in neurocritical care.

False localizing signs (FLS) and other misleading neurological signs have long been an intractable aspect of neurocritical care. Because they suggest an incorrect location or etiology of the pathological lesion, they have often led to misdiagnosis and mismanagement of the patient. Here, we reviewed the existing literature to provide an updated, comprehensive descriptive review of these difficult to diagnose signs in neurocritical care. For each sign presented, we discuss the non-false localizing presentation of symptoms, the common FLS or misleading presentation, etiology/pathogenesis of the sign, and diagnosis, as well as any other clinically relevant considerations. Within cranial neuropathies, we cover cranial nerves III, IV, V, VI, VII, VIII, as well as multiple cranial nerve involvement of IX, X, and XII. FLS ophthalmologic symptoms indicate diagnostically challenging neurological deficits, and here we discuss downbeat nystagmus, ping-pong-gaze, one-and-a-half syndrome, and wall-eyed bilateral nuclear ophthalmoplegia (WEBINO). Cranial herniation syndromes are integral to any discussion of FLS and here we cover Kernohan's notch phenomenon, pseudo-Dandy Walker malformation, and uncal herniation. FLS in the spinal cord have also been relatively well documented, but in addition to compressive lesions, we also discuss newer findings in radiculopathy and disc herniation. Finally, pulmonary syndromes may sometimes be overlooked in discussions of neurological signs but are critically important to recognize and manage in neurocritical care, and here we discuss Cheyne-Stokes respiration, cluster breathing, central neurogenic hyperventilation, ataxic breathing, Ondine's curse, and hypercapnia. Though some of these signs may be rare, the framework for diagnosing and treating them must continue to evolve with our growing understanding of their etiology and varied presentations.

Effect of Helicopter Transportation of Acute Ischemic Stroke Patients on Mortality and Functional Outcomes: A Systematic Review and Meta-Analysis.

OBJECTIVE: The "time is brain" concept denotes the importance of the expedited transfer of patients to stroke care centers. Helicopter emergency medical services (HEMS) can reduce the time to definitive care, which could improve neurologic prognosis and reduce mortality. METHODS: Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement, a search for randomized controlled trials, nonrandomized controlled trials, and prospective and retrospective cohort studies was performed through specific databases from inception to February 2020. Helicopter, acute stroke, and their synonyms (according to Medical Subject Headings) were included in this search. The Newcastle-Ottawa Scale was used to assess the quality of the included studies, and the Egger test was used to assess for publication bias. RESULTS: A total of 8 studies matched the inclusion criteria and were included for meta-analysis. The overall number recruited for helicopter transportation was 1,372, and for emergency standard transportation, it was 8,587. The association among HEMS and mortality was not statistically significant (odds ratio [OR] = 0.7; 95% confidence interval [CI], 0.60-1.06; P = .12). There was a significant association between good outcomes and HEMS (OR = 2; 95% CI, 1.79-2.34; P ≤ .001), and the overall poor neurologic outcome was reduced (OR = 0.52; 95% CI, 0.46-0.60; P ≤ .001). CONCLUSION: A good neurologic outcome was higher with HEMS compared with emergency standard transportation. The mortality rate was less in the emergency standard transportation group after pooled analysis but was not significant; the reduction in a poor outcome was statistically significant.

Endovascular Thrombectomy for Treatment of Acute Ischemic Stroke During Pregnancy and the Early Postpartum Period.

BACKGROUND AND PURPOSE: Acute ischemic stroke (AIS) is a rare occurrence during pregnancy and the postpartum period. Existing literature evaluating endovascular mechanical thrombectomy (MT) for this patient population is limited. METHODS: The National Inpatient Sample was queried from 2012 to 2018 to identify and characterize pregnant and postpartum patients (up to 6 weeks following childbirth) with AIS treated with MT. Complications and outcomes were compared with nonpregnant female patients treated with MT and to other pregnant and postpartum patients managed medically. Complex samples regression models and propensity score matching were implemented to assess adjusted associations and to address confounding by indication, respectively. RESULTS: Among 4590 pregnant and postpartum patients with AIS, 180 (3.9%) were treated with MT, and rates of utilization increased following the MT clinical trial era (2015-2018; 1.9% versus 5.3%, P=0.011). Compared with nonpregnant patients with AIS treated with MT, they experienced lower rates of intracranial hemorrhage (11% versus 24%, P=0.069) and poor functional outcome (50% versus 72%, P=0.003) at discharge. Pregnant/postpartum status was independently associated with a lower likelihood of development of intracranial hemorrhage (adjusted odds ratio, 0.26 [95% CI, 0.09-0.70]; P=0.008) following multivariable analysis adjusting for age, illness severity, and stroke severity. Following propensity score matching, pregnant and postpartum patients treated with MT and those medically managed differed in frequency of venous thromboembolism (17% versus 0%, P=0.001) and complications related to pregnancy (44% versus 64%, P=0.034), but not in functional outcome at discharge or hospital length of stay. Pregnant and postpartum women treated with MT did not experience mortality or miscarriage during hospitalization. CONCLUSIONS: This large-scale analysis utilizing national claims data suggests that MT is a safe and efficacious therapy for AIS during pregnancy and the postpartum period. In the absence of prospective clinical trials, population-based cross-sectional analyses such as the present study provide valuable clinical insight.

Machine Learning and Artificial Intelligence in Neurocritical Care: a Specialty-Wide Disruptive Transformation or a Strategy for Success.

PURPOSE OF REVIEW: Neurocritical care combines the complexity of both medical and surgical disease states with the inherent limitations of assessing patients with neurologic injury. Artificial intelligence (AI) has garnered interest in the basic management of these complicated patients as data collection becomes increasingly automated. RECENT FINDINGS: In this opinion article, we highlight the potential AI has in aiding the clinician in several aspects of neurocritical care, particularly in monitoring and managing intracranial pressure, seizures, hemodynamics, and ventilation. The model-based method and data-driven method are currently the two major AI methods for analyzing critical care data. Both are able to analyze the vast quantities of patient data that are accumulated in the neurocritical care unit. AI has the potential to reduce healthcare costs, minimize delays in patient management, and reduce medical errors. However, these systems are an aid to, not a replacement for, the clinician's judgment.

Circulating mitochondrial DAMPs cause inflammatory responses to injury.

Injury causes a systemic inflammatory response syndrome (SIRS) that is clinically much like sepsis. Microbial pathogen-associated molecular patterns (PAMPs) activate innate immunocytes through pattern recognition receptors. Similarly, cellular injury can release endogenous 'damage'-associated molecular patterns (DAMPs) that activate innate immunity. Mitochondria are evolutionary endosymbionts that were derived from bacteria and so might bear bacterial molecular motifs. Here we show that injury releases mitochondrial DAMPs (MTDs) into the circulation with functionally important immune consequences. MTDs include formyl peptides and mitochondrial DNA. These activate human polymorphonuclear neutrophils (PMNs) through formyl peptide receptor-1 and Toll-like receptor (TLR) 9, respectively. MTDs promote PMN Ca(2+) flux and phosphorylation of mitogen-activated protein (MAP) kinases, thus leading to PMN migration and degranulation in vitro and in vivo. Circulating MTDs can elicit neutrophil-mediated organ injury. Cellular disruption by trauma releases mitochondrial DAMPs with evolutionarily conserved similarities to bacterial PAMPs into the circulation. These signal through innate immune pathways identical to those activated in sepsis to create a sepsis-like state. The release of such mitochondrial 'enemies within' by cellular injury is a key link between trauma, inflammation and SIRS.

Use of Tethers for Proximal Junctional Kyphosis Prophylaxis in Adult Spinal Deformity Surgery: A Review of Current Clinical Evidence.

BACKGROUND: Surgery for adult spinal deformity (ASD) often involves long-segment posterior instrumentation that introduces stress at the proximal junction that can result in proximal junctional kyphosis (PJK) or proximal junctional failure (PJF). Recently, the use of tethers at the proximal junction has been proposed as a means of buffering the transitional stresses and reducing the risk of PJK/PJF. Our objectives are to summarize the clinical literature on proximal junctional tethers for PJK/PJF prophylaxis. METHODS: Articles published between 1 January 2000 and 10 November 2022 were identified via a PubMed search using combinations of the search terms "spine surgery," "ASD," "complication," "surgery," "PJK," "PJF," "tether," "sublaminar band," and "prophylaxis." No restrictions were placed on the number of patients, surgical indications, or surgical procedures. Relevant articles were reviewed and summarized. RESULTS: Fifteen articles were identified, including 2 prospective cohorts (Level II), 10 retrospective cohorts (Level III), and 3 retrospective case series (Level IV). All studies were published between 2016 and 2022, and all focused on ASD patient populations. The mean age in each study ranged from 55 to 69 years, and most studies had a mean follow-up of at least 12 months (range, 5.5-45.4 months). Eleven studies used a polyethylene tether, 2 used soft sublaminar cables, and 2 used semitendinous allograft. The tether extended to the UIV+1 or UIV+2, passing either through or around the spinous processes, in 13 studies. In the remaining 2 studies, the tether was passed sublaminar at the UIV+1. Fourteen studies favored the use of tethers with regard to reduction of PJK/PJF rates, and one demonstrated similar rates of PJK between the tether and no-tether groups. CONCLUSIONS: PJK/PJF remain major challenges in ASD surgery. Most early studies suggest that the use of tethers for ligamentous augmentation may help to mitigate the development of PJK/PJF. However, the multifactorial etiology of PJK/PJF makes it unlikely that any single technique will solve this complex problem. Further study is needed to address not only the effectiveness of junctional tethers but also to clarify whether there are optimal tether configurations, tether materials, and tether tension. LEVEL EVIDENCE: 3.

Thecal sac ligation in the setting of thoracic spondyloptosis with complete cord transection.

Background: Traumatic spondyloptosis (TS) with complete spinal cord transection and unrepairable durotomy is particularly rare and can lead to a difficult-to-manage cerebrospinal fluid (CSF) leak. Methods: We performed a systematic review of the literature on TS and discuss the management strategies and outcomes of TS with cord transection and significant dural tear. We also report a novel case of a 26-year-old female who presented with thoracic TS with complete spinal cord transection and unrepairable durotomy with high-flow CSF leak. Results: Of 93 articles that resulted in the search query, 13 described cases of TS with complete cord transection. The approach to dural repair was only described in 8 (n = 20) of the 13 articles. The dura was not repaired in two (20%) of the cases. Ligation of the proximal end of the dural defect was done in 15 (75%) of the cases, all at the same institution. One (5%) case report describes ligation of the distal end; one (5%) case describes the repair of the dura with duraplasty; and another (5%) case describes repair using muscle graft to partially reconstruct the defect. Conclusion: Suture ligation of the thecal sac in the setting of traumatic complete spinal cord transection with significant dural disruption has been described in the international literature and is a safe and successful technique to prevent complications associated with persisting high-flow CSF leakage. To the best of our knowledge, this is the first report of thecal sac ligation of the proximal end of the defect from the United States.

Significant increase in mortality and risk of acute ischemic stroke in infective endocarditis patients with subarachnoid hemorrhage secondary to mycotic aneurysms.

Infective Endocarditis (IE) patients are known to have a variety of complications with one of the rarest, but serious being cerebral mycotic aneurysm, which can result in subarachnoid hemorrhage (SAH). Using the National In-Patient Sample database, we sought to determine the rate of acute ischemic stroke (AIS) and outcomes in IE- patients with and without SAH. In total, we identified 82,844 IE-patients from 2010 to 2016, of which 641 had a concurrent diagnosis of SAH. IE patients with SAH had a more complicated course, higher mortality rate (OR 4.65 CI 95% 3.9-5.5, P < 0.001), and worse outcomes. This patient population also had a significantly higher rate of AIS (OR 6.3 CI 95% 5.4-7.4, P < 0.001). Overall, 41.5% of IE-patients with SAH had AIS during their hospitalization as compared to 10.1% of IE only patients. IE-patients with SAH were more likely to undergo endovascular treatment (3.6%) with 0.8% of the IE patients with AIS undergoing mechanical thrombectomy. While IE-patients are at risk for various complications, our study suggests a significant increase in the mortality and risk of AIS in those with SAH.

An institutional report of heparin induced thrombocytopenia type II in aneurysmal subarachnoid hemorrhage patients.

BACKGROUND: Heparin induced thrombocytopenia Type II (HIT-II) is a dangerous thromboembolic complication of heparin therapy. The current literature on incidence and outcomes of HIT-II in aneurysmal subarachnoid hemorrhage (aSAH) patients remains sparse. OBJECTIVE: We report our institution's incidence and outcomes of HIT-II in aSAH patients. METHODS: We performed a retrospective cohort study at an academic medical center between June 2014 and July 2018. All patients had aSAH confirmed by digital subtraction angiography. Diagnosis of HIT-II was determined by positive results on both heparin PF4-platelet antibody ELISA (anti-PF4) and serotonin release assay (SRA). RESULTS: 204 patients met inclusion criteria. Seven patients (7/204, 3.5%) underwent laboratory testing, three of whom met clinical criteria. HIT-II incidence was confirmed in two of these seven patients (2/204, 0.98%), who had high BMI and T4 scores. CONCLUSION: Our institution's report of HIT-II incidence in aSAH patients is lower than previously reported in this population and more closely parallels HIT-II incidence in the general and surgical ICU setting. Widely-accepted American College of Chest Physicians (ACCP) clinical diagnostic criteria in conjunction with anti-PF4 and SRA testing is the gold standard of clinical diagnosis of HIT-II in aSAH patients.

Significant Mortality Associated With COVID-19 and Comorbid Cerebrovascular Disease: A Quantitative Systematic Review.

We report the first quantitative systematic review of cerebrovascular disease in coronavirus disease 2019 (COVID-19) to provide occurrence rates and associated mortality. Through a comprehensive search of PubMed we identified 8 cohort studies, 5 case series, and 2 case reports of acute cerebrovascular disease in patients with confirmed COVID-19 diagnosis. Our first meta-analysis utilizing the identified publications focused on comorbid cerebrovascular disease in recovered and deceased patients with COVID-19. We performed 3 additional meta-analyses of proportions to produce point estimates of the mortality and incidence of acute cerebrovascular disease in COVID-19 patients. Patient's with COVID-19 who died were 12.6 times more likely to have a history of cerebrovascular disease. We estimated an occurrence rate of 2.6% (95% confidence interval, 1.2-5.4%) for acute cerebrovascular disease among consecutively admitted patients with COVID-19. While for those with severe COVID-19' we estimated an occurrence rate of 6.5% (95% confidence interval, 4.4-9.6%). Our analysis estimated a rate of 35.5% for in-hospital mortality among COVID-19 patients with concomitant acute cerebrovascular disease. This was consistent with a mortality rate of 34.0% which we obtained through an individual patient analysis of 47 patients derived from all available case reports and case series. COVID-19 patients with either acute or chronic cerebrovascular disease have a high mortality rate with higher occurrence of cerebrovascular disease in patients with severe COVID-19.

How Good Are Surgeons at Achieving Their Preoperative Goal Sagittal Alignment Following Adult Deformity Surgery?

STUDY DESIGN: Multicenter, prospective cohort. OBJECTIVES: Malalignment following adult spine deformity (ASD) surgery can impact outcomes and increase mechanical complications. We assess whether preoperative goals for sagittal alignment following ASD surgery are achieved. METHODS: ASD patients were prospectively enrolled based on 3 criteria: deformity severity (PI-LL ≥25°, TPA ≥30°, SVA ≥15 cm, TCobb≥70° or TLCobb≥50°), procedure complexity (≥12 levels fused, 3-CO or ACR) and/or age (>65 and ≥7 levels fused). The surgeon documented sagittal alignment goals prior to surgery. Goals were compared with achieved alignment on first follow-up standing radiographs. RESULTS: The 266 enrolled patients had a mean age of 61.0 years (SD = 14.6) and 68% were women. Mean instrumented levels was 13.6 (SD = 3.8), and 23.2% had a 3-CO. Mean (SD) offsets (achieved-goal) were: SVA = -8.5 mm (45.6 mm), PI-LL = -4.6° (14.6°), TK = 7.2° (14.7°), reflecting tendencies to undercorrect SVA and PI-LL and increase TK. Goals were achieved for SVA, PI-LL, and TK in 74.4%, 71.4%, and 68.8% of patients, respectively, and was achieved for all 3 parameters in 37.2% of patients. Three factors were independently associated with achievement of all 3 alignment goals: use of PACs/equivalent for surgical planning (P < .001), lower baseline GCA (P = .009), and surgery not including a 3-CO (P = .037). CONCLUSIONS: Surgeons failed to achieve goal alignment of each sagittal parameter in ∼25-30% of ASD patients. Goal alignment for all 3 parameters was only achieved in 37.2% of patients. Those at greatest risk were patients with more severe deformity. Advancements are needed to enable more consistent translation of preoperative alignment goals to the operating room.

Neutrophil-Lymphocyte ratio is associated with poor clinical outcome after mechanical thrombectomy in stroke in patients with COVID-19.

BACKGROUND: The neutrophil-lymphocyte ratio (NLR) is emerging as an important biomarker of acute physiologic stress in a myriad of medical conditions, and is a confirmed poor prognostic indicator in COVID-19. OBJECTIVE: We sought to describe the role of NLR in predicting poor outcome in COVID-19 patients undergoing mechanical thrombectomy for acute ischemic stroke. METHODS: We analyzed NLR in COVID-19 patients with large vessel occlusion (LVO) strokes enrolled into an international 12-center retrospective study of laboratory-confirmed COVID-19, consecutively admitted between March 1, 2020 and May 1, 2020. Increased NLR was defined as ≥7.2. Logistic regression models were generated. RESULTS: Incidence of LVO stroke was 38/6698 (.57%). Mean age of patients was 62 years (range 27-87), and mortality rate was 30%. Age, sex, and ethnicity were not predictive of mortality. Elevated NLR and poor vessel recanalization (Thrombolysis in Cerebral Infarction (TICI) score of 1 or 2a) synergistically predicted poor outcome (likelihood ratio 11.65, p = .003). Patients with NLR > 7.2 were 6.8 times more likely to die (OR 6.8, CI95% 1.2-38.6, p = .03) and almost 8 times more likely to require prolonged invasive mechanical ventilation (OR 7.8, CI95% 1.2-52.4, p = .03). In a multivariate analysis, NLR > 7.2 predicted poor outcome even when controlling for the effect of low TICI score on poor outcome (NLR p = .043, TICI p = .070). CONCLUSIONS: We show elevated NLR in LVO patients with COVID-19 portends significantly worse outcomes and increased mortality regardless of recanalization status. Severe neuro-inflammatory stress response related to COVID-19 may negate the potential benefits of successful thrombectomy.

Resection of Thoracic Intramedullary Breast Metastasis Through the Dorsal Root Entry Zone: 2-Dimensional Operative Video.

Intramedullary spinal cord metastases (ISCMs) are rare, representing 8.5% of central nervous system metastases and 5% of intramedullary lesions.1 With the advent of immunotherapy leading to longer-term survival for cancer patients, intramedullary metastases are on the rise.2 A 43-year-old female presented with acute right leg weakness and sensory loss (Video 1). Magnetic resonance imaging revealed an avidly enhancing mass in the spinal cord at T6 with associated edema. Surgical resection was performed for tumor debulking to stabilize and ideally improve neurologic function, as well as for tissue acquisition for molecular profiling and targeted therapy. ISCMs are typically entered via midline myelotomy after a standard posterior exposure.3 However, on dural opening and visualization of the spinal cord, it was apparent that the tumor involved the right T6 nerve root. The decision was then made to enter the lesion via the T6 dorsal root entry zone (DREZ).4 Microsurgical resection of the tumor was performed with the aid of ultrasound and D-wave motor monitoring. Postoperative magnetic resonance imaging showed gross total resection and the patient was discharged to acute rehabilitation with increased right leg weakness and stable sensation. We demonstrate that for ISCM involving the exiting nerve root, DREZ myelotomy is a viable alternative to midline myelotomy. We strongly recommend use of D-wave monitoring in such cases as it clearly impacted our ability to maximize the resection. This is the first video where the DREZ approach is emphasized along with utilization of D-wave monitoring. The patient consented to the surgical procedure and the use of intraoperative video for education purposes.

Molecular Stratification of Medulloblastoma: Clinical Outcomes and Therapeutic Interventions.

Medulloblastoma (MB) is the most common malignant pediatric posterior fossa tumor. Recent genetic, epigenetic, and transcriptomic analyses have classified MB into three subgroups, Wingless Type (WNT), Sonic Hedgehog (SHH), and non-WNT/non-SHH (originally termed Group 3 and Group 4), with discrete patient profiles and prognoses. WNT is the least common subgroup with the best prognosis, characterized by nuclear ß-catenin expression, mutations in Catenin beta-1 (CTNNB1), and chromosome 6 monosomy. SHH tumors contain mutations and alterations in GLI1, GLI2, SUFU, and PTCH1 genes, which constitutively activate the SHH pathway. Originally, the presence of TP53 gene alterations and/or MYC amplifications was considered the most reliable prognostic factor. However, recent molecular analyses have subdivided SHH MB into several subtypes with distinct characteristics such as age, TP53 mutation, MYC amplification, presence of metastases, TERT promoter alterations, PTEN loss, and other chromosomal alterations as well as SHH pathway-related gene mutations. The third non-WNT/non-SHH MB (Group3/4) subgroup is genetically highly heterogeneous and displays several molecular patterns, including MYC and OTX2 amplification, GFI1B activation, KBTBD4 mutation, GFI1 rearrangement, PRDM6 enhancer hijacking, KDM6A mutation, LCA histology, chromosome 10 loss, isochromosome 17q, SNCAIP duplication, and CDK6 amplification. However, based on molecular profiling and methylation patterns, additional non-WNT/non-SHH MB subtypes have been described. Recent WHO (2021) guidelines stratified MB into four molecular subgroups with four and eight further subgroups for SHH and non-WNT/non-SHH MB, respectively. In this review, we discuss advancements in genetics, epigenetics, and transcriptomics for better characterization, prognostication, and treatment of MB using precision medicine.

Low serum albumin as a risk factor for delayed cerebral ischemia following aneurysmal subarachnoid hemorrhage: eICU collaborative research database analysis.

BACKGROUND: Delayed cerebral ischemia (DCI) represents a devastating complication of aneurysmal subarachnoid hemorrhage (aSAH) and is a significant predictor of morbidity and mortality. Recent studies have implicated inflammatory processes in the pathogenesis of DCI. METHODS: aSAH patient data were retrospectively obtained from the eICU Collaborative Research Database (eICU CRD). Multivariable logistic regression models and receiver operating characteristic (ROC) curve analyses were employed to assess the association between low serum albumin (< 3.4 g/dL) and clinical endpoints: DCI and in-hospital mortality. RESULTS: Among 276 aSAH patients included in the analysis, 35.5% (n=98) presented with low serum albumin levels and demonstrated a higher incidence of DCI (18.4% vs. 8.4%, OR=2.45, 95% CI 1.17, 5.10; p=0.017) and in-hospital mortality (27.6% vs. 16.3%, OR=1.95, 95% CI 1.08, 3.54; p=0.027) compared to patients with normal admission albumin values. In a multivariable model controlling for age and World Federation of Neurosurgical Societies grade, low serum albumin remained significantly associated with DCI (OR=2.52, 95% CI 1.18, 5.36; p=0.017), but not with in-hospital mortality. A combined model for prediction of DCI, encompassing known risk factors in addition to low serum albumin, achieved an area under the curve of 0.65 (sensitivity=0.55, specificity=0.75). CONCLUSIONS: Serum albumin, a routine and inexpensive laboratory measurement, can may potentially aid in the identification of patients with aSAH at risk for the development of DCI.

Frailty is a risk factor for intracranial abscess and is associated with longer length of stay: a retrospective single institution case-control study.

BACKGROUND: Intracranial abscess (IA) causes significant morbidity and mortality. The impact of baseline frailty status on post-operative outcomes of IA patients remains largely unknown. The present study evaluated if frailty status can be used to prognosticate outcomes in IA patients. METHODS: We retrospectively reviewed all IA patients undergoing craniotomy at our institution from 2011 to 2018 (n =18). These IA patients were age and gender matched with patients undergoing craniotomy for intracranial tumor (IT), an internal control for comparison. Demographic and clinical data were collected to measure frailty, using the modified frailty index-11 (mFI-11), pre-operative American Society of Anesthesiologists Physical Status Classification System (ASA), and study their association with post-operative complications, as measured by the Clavien-Dindo Grade (CDG). RESULTS: No significant difference in mFI-11 or ASA score was observed between the IA and IT groups (p = 0.058 and p = 0.131, respectively). IA patients had significantly higher CDG as compared with the control IT patients (p < 0.001). There was a trend towards increasing LOS in the IA group as compared to the IT group (p = 0.053). Increasing mFI and ASA were significant predictors of LOS by multiple linear regression in the IA group (p = 0.006 and p = 0.001, respectively), but not in the control IT group. Neither mFI-11 nor ASA were found to be predictors for CDG in either group. Within this case-control group of patients, we found an increase for odds of having IA with increasing mFI (OR 1.838, CI 95% 1.016-3.362, p = 0.044). CONCLUSIONS: Frail IA patients tend to have more severe postoperative complications. The mFI-11 seems to predict increased resource utilization in the form of LOS. This study provides the initial retrospective data of another neurosurgical pathology where frailty leads to significantly worse outcomes. We also found that mFI may serve as a potential risk factor for severe disease.

Targeting the mTOR pathway using novel ATP­competitive inhibitors, Torin1, Torin2 and XL388, in the treatment of glioblastoma.

Mechanistic target of rapamycin (mTOR), which functions via two multiprotein complexes termed mTORC1 and mTORC2, is positioned in the canonical phosphoinositide 3­kinase­related kinase (PI3K)/AKT (PI3K/AKT) pathways. These complexes exert their actions by regulating other important kinases, such as 40S ribosomal S6 kinases (S6K), eukaryotic translation initiation factor 4E (elF4E)­binding protein 1 (4E­BP1) and AKT, to control cell growth, proliferation, migration and survival in response to nutrients and growth factors. Glioblastoma (GB) is a devastating form of brain cancer, where the mTOR pathway is deregulated due to frequent upregulation of the Receptor Tyrosine Kinase/PI3K pathways and loss of the tumor suppressor phosphatase and tensin homologue (PTEN). Rapamycin and its analogs were less successful in clinical trials for patients with GB due to their incomplete inhibition of mTORC1 and the activation of mitogenic pathways via negative feedback loops. Here, the effects of selective ATP­competitive dual inhibitors of mTORC1 and mTORC2, Torin1, Torin2 and XL388, are reported. Torin2 exhibited concentration­dependent pharmacodynamic effects on inhibition of phosphorylation of the mTORC1 substrates S6KSer235/236 and 4E­BP1Thr37/46 as well as the mTORC2 substrate AKTSer473 resulting in suppression of tumor cell migration, proliferation and S­phase entry. Torin1 demonstrated similar effects, but only at higher doses. XL388 suppressed cell proliferation at a higher dose, but failed to inhibit cell migration. Treatment with Torin1 suppressed phosphorylation of proline rich AKT substrate of 40 kDa (PRAS40) at Threonine 246 (PRAS40Thr246) whereas Torin2 completely abolished it. XL388 treatment suppressed the phosphorylation of PRAS40Thr246 only at higher doses. Drug resistance analysis revealed that treatment of GB cells with XL388 rendered partial drug resistance, which was also seen to a lesser extent with rapamycin and Torin1 treatments. However, treatment with Torin2 completely eradicated the tumor cell population. These results strongly suggest that Torin2, compared to Torin1 or XL388, is more effective in suppressing mTORC1 and mTORC2, and therefore in the inhibition of the GB cell proliferation, dissemination and in overcoming resistance to therapy. These findings underscore the significance of Torin2 in the treatment of GB.

Acute subdural hematomas secondary to aneurysmal subarachnoid hemorrhage confer poor prognosis: a national perspective.

BACKGROUND: Aneurysmal ruptures typically cause subarachnoid bleeding with intraparenchymal and intraventricular extension. However, rare instances of acute aneurysmal ruptures present with concomitant, non-traumatic subdural hemorrhage (SDH). We explored the incidence and difference in outcomes of SDH with aneurysmal subarachnoid hemorrhage (aSAH) as compared with aSAH alone. METHODS: Retrospective cohort study from 2012 to 2015 from the National (Nationwide) Inpatient Sample (NIS) (20% stratified sample of all hospitals in the United States). NIS database (2012 to September 2015) queried to identify all patients presenting with aSAH. From this population, the patients with concomitant SDH were identified. RESULTS: A total of 10 075 patients with both cerebral aneurysms and aSAH were included. Of these, 335 cases of concomitant SDH and aSAH were identified. There was no significant change in the rate of SDH in aSAH over time. SDH with aSAH patients had a mortality of 24% compared with 12% (p=0.003) in the SAH only group, and only 16% were discharged home vs 37% (p=0.003) in the SAH group. CONCLUSIONS: There is a 3.5% incidence of acute SDH in patients presenting with non-traumatic aSAH. Patients with SDH and aSAH have nearly double the mortality, higher rate of discharge to nursing home and rehabilitation, and a significantly lower rate of discharge to home and return to routine functioning. This information is useful in counseling and prognostication of patients with concomitant SDH and aSAH.

Understanding the Biological Basis of Glioblastoma Patient-derived Spheroids.

BACKGROUND/AIM: Resistance to glioblastoma (GB) therapy is attributed to the presence of glioblastoma stem cells (GSC). Here, we defined the behavior of GSC as it pertains to proliferation, migration, and angiogenesis. MATERIALS AND METHODS: Human-derived GSC were isolated and cultured from GB patient tumors. Xenograft GSC were extracted from the xenograft tumors, and spheroids were created and compared with human GSC spheroids by flow cytometry, migration, proliferation, and angiogenesis assays. Oct3/4 and Sox2, GFAP, and Ku80 expression was assessed by immunoanalysis. RESULTS: The xenograft model showed the formation of two different tumors with distinct characteristics. Tumors formed at 2 weeks were less aggressive with well-defined margins, whereas tumors formed in 5 months were diffuse and aggressive. Expression of Oct3/4 and Sox2 was positive in both human and xenograft GSC. Positive Ku80 expression in xenograft GSC confirmed their human origin. Human and xenograft GSC migrated vigorously in collagen and Matrigel, respectively. Xenograft GSC displayed a higher rate of migration and invasion than human GSC. CONCLUSION: Human GSC were more aggressive in growth and proliferation than xenograft GSC, while xenograft GSC had increased invasion and migration compared to human GSC. A simple in vitro spheroid system for GSC provides a superior platform for the development of precision medicine in the treatment of GB.

Involvement of mTOR Pathways in Recovery from Spinal Cord Injury by Modulation of Autophagy and Immune Response.

Traumatic spinal cord injury (SCI) is untreatable and remains the leading cause of disability. Neuroprotection and recovery after SCI can be partially achieved by rapamycin (RAPA) treatment, an inhibitor of mTORC1, complex 1 of the mammalian target of rapamycin (mTOR) pathway. However, mechanisms regulated by the mTOR pathway are not only controlled by mTORC1, but also by a second mTOR complex (mTORC2). Second-generation inhibitor, pp242, inhibits both mTORC1 and mtORC2, which led us to explore its therapeutic potential after SCI and compare it to RAPA treatment. In a rat balloon-compression model of SCI, the effect of daily RAPA (5 mg/kg; IP) and pp242 (5 mg/kg; IP) treatment on inflammatory responses and autophagy was observed. We demonstrated inhibition of the mTOR pathway after SCI through analysis of p-S6, p-Akt, and p-4E-BP1 levels. Several proinflammatory cytokines were elevated in pp242-treated rats, while RAPA treatment led to a decrease in proinflammatory cytokines. Both RAPA and pp242 treatments caused an upregulation of LC3B and led to improved functional and structural recovery in acute SCI compared to the controls, however, a greater axonal sprouting was seen following RAPA treatment. These results suggest that dual mTOR inhibition by pp242 after SCI induces distinct mechanisms and leads to recovery somewhat inferior to that following RAPA treatment.