Showing papers in "Journal of Neurosurgical Sciences in 2018"

Epidemiology of severe traumatic brain injury.

Abstract: About 5.48 million people are estimated to suffer from severe traumatic brain injury (TBI) each year (73 cases per 100,000 people). The WHO estimates that almost 90% of deaths due to injuries occur in low- and middle-income countries (LMICs), where the 85% of population live. Of these trauma-related deaths TBI is the main cause of one-third to one-half and represents the greatest cause of death and disability globally among all trauma-related injuries. The primary causes of TBI vary by age, socioeconomic factors, and geographic region, so any planned interventions must take in account this variability. The road traffic injuries (RTI) scenario is still strictly connected to the analysis of the global incidence of TBI, and to the reason why the LMICs experience nearly 3 times as many cases of TBI proportionally than high-income countries (HICs). The proportion of TBIs resulting from road traffic collisions was greatest in Africa and Southeast Asia (both 56%) and lowest in North America (25%). In HICs, falls and RTIs were reported most frequently as cause of TBI, but the traumas attributable to RTIs dropped from 39% in 2003 to 24% in 2012, while those attributable to falls increased from 43% to 54% respectively, with an increase TBI in the elderly (>65 years) due to falls. Differently from HICs, the population with the peak of TBI incidence is younger in LMICs, with an age between 28.8 and 33.1, as extensively reported. The burden of disease is significant; between 1,730,000 and 1,965,000 lives could be saved if global trauma care were improved in LMICs. Clinical practice recommendation should be developed and created in environments where the severe TBI mainly occurs. The applicability of high-income-country clinical research standards in LMICs is an important topic for future international research.

Natural history of brain arteriovenous malformations: systematic review.

Abstract: INTRODUCTION The appropriate interpretation of natural history of brain arteriovenous malformations (bAVMs) and of factors that negatively affect the risk of future hemorrhage are important when recommending management pathways. With the present systematic review, we aim to provide an overview of the available evidence on natural history of brain arteriovenous malformations (bAVMs), focusing on hemorrhage rates and risk factors for future hemorrhage. EVIDENCE ACQUISITION We performed a systematic literature analysis using the Ovid Medline database, encompassing English language studies (published between 1980 and 2018) reporting the natural history of untreated bAVMs. Annual hemorrhage rates in both unruptured and previously ruptured bAVMs, as well as risk factors for future hemorrhage were extracted for analysis. EVIDENCE SYNTHESIS Eighteen studies with a total of 8418 bAVM-cases could be extracted from the literature. Seventeen studies reported annual hemorrhage rates and ten studies reported risk factors for future hemorrhage. The average annualized hemorrhage rate was 2.2% for unruptured bAVMs and 4.3%, for bAVMs that presented with hemorrhage. Prior hemorrhage and deep AVM location could be identified as most consistently reported risk factors for future hemorrhage. CONCLUSIONS Previously ruptured bAVMs have a higher annual hemorrhage rate than enraptured bAVMs. Deep bAVM location and prior hemorrhage may increase the risk for subsequent hemorrhage.

The utilization of fluorescein in brain tumor surgery: a systematic review.

Abstract: Introduction Sodium fluorescein (SF) is a green, water-soluble dye with the capacity to accumulate in cerebral areas as a result of damaged blood-brain barrier (BBB); this property allows SF to concentrate specifically at the tumor site of various types of brain neoplasms, making the tumor tissue more clearly visible. Evidence acquisition A literature search (1947-2018) was conducted with the keywords "fluorescein neurosurgery," "YELLOW neurosurgery," "fluorescein brain tumor," "YELLOW brain tumor." We included clinical studies, clinical trials, observational studies, only conducted on humans and concerning surgery; in addition, we have included 3 articles derived from the analysis of the references of other papers. Ultimately, 57 articles were included for further analysis. Evidence synthesis Fluorescein as a fluorescent tracer in neuro-oncology is gaining a wider acceptance in the neurosurgical literature: until February 1st, 2018, at least 1099 neuro-oncological patients have been operated through fluorescein-assistance, mostly only after 2012. The most important application remains the aim to improve tumor visualization and extent of resection for high-grade gliomas (HGG), but the nonspecific mechanism of action is the theoretical base for its use also for tumors different from HGG. Nevertheless, no homogenous protocol of fluorescein utilization in neurosurgical oncology can be found in literature. Conclusions Fluorescein-guided surgery is a safe and effective technique to improve visualization and resection of different CNS tumors and conditions, based on BBB alteration, with a growing evidence-based background.

Surgical management of traumatic brain injury.

Abstract: Traumatic brain injury (TBI) remains a leading cause of mortality and disability worldwide. Surgical intervention is one of the main pillars of TBI management. The mainstay of treatment for substantial intracranial hematomas is surgical evacuation. In addition, patients with TBI may have brain swelling and increased intracranial pressure. If the latter is refractory to medical management, surgical interventions can be helpful. In this review we seek to outline the major tenets of the surgical management of TBI.

A perspective on the use of an enhanced recovery program in open, non-instrumented day surgery for degenerative lumbar and cervical spinal conditions.

Abstract: Background A means of significantly shortening patients' length of hospital stay, improving their outcome and thereby also reducing costs is to use an enhanced recovery program (ERP) which is increasingly being used in a number of surgical sub-specialties. This paper provides a perspective on its prospective use in a wide-ranging, unselected cohort of patients undergoing open spinal surgery for degenerative lumbar and cervical spinal conditions. Selected spinal cases undergoing day surgery have been increasingly reported. Methods A prospective, unselected, consecutive cohort of 246 cases, over an 18-month period, undergoing open, non-instrumented decompression spinal surgery and using ERP (and the concept of "bundles of care") was analyzed. Results Nine cases could not be included as they did not fully meet the entry criteria. No routine follow-up was arranged for the study group. The ages ranged widely, from 23-90 years (mean 57). In 187 the surgery for degenerative conditions was lumbar and in 50 cervical. The ASA (American Association of Anesthesiologists) ratings were 108=1; 107=2 and 22=3. Using the United Kingdom (UK) National Health Service (NHS) definitions of length of stay 225 (95%) could be finally classified as "ambulatory" and 12 (5%) were "short stay". A sub-cohort of 126 (53.2%) were "day cases". The follow-up was >1 year for all. There were no wound infections reported; 5 postdischarge cases (2.1%) needed to be seen in the Accident and Emergency (AE and there were 7 re-admissions (2.5%), between 4 and 30 days, and of these 6 required a further surgical procedure. There were no long-term instability complications reported in this cohort. Conclusions ERP can be used for spinal surgery. There were identifiable and correctable medical and social factors found on analysis which could significantly increase the "day cases" number to over 90%.

Contemporary endovascular techniques for the curative treatment of cerebral arteriovenous malformations and review of neurointerventional outcomes.

Abstract: Introduction Since the first landmark randomized trials on unruptured bAVMs were published, there has been emerging concerns about the role of endovascular therapy. For bAVMs considered inoperable, embolization remains an option worth considering, especially in young patients presenting with a rupture. We aimed to review the curative potential of contemporary stand-alone embolization techniques enabling high occlusion rates and their respective short and long term safety profile. Evidence acquisition We performed a PubMed search with the terms "curative embolization of brain arteriovenous malformations" and "endovascular cure of brain arteriovenous malformations" focusing on the last ten years (2008-2018) and compliant to the PRISMA reporting guidelines. We then screened the prospective and retrospective studies of pediatric or adult populations that contained patient demographics, ruptured or unruptured presentation, and bAVM grade according to the Spetzler-Martin (SM) classification, exclusive or stand-alone endovascular treatment without previous embolization, micro-, radio- or stereotactic surgery, number of sessions, type of access, technique(s) and embolic agents used, rate of angiographically confirmed complete occlusion at least 3 months after obliteration stratified by AVM grade or subtype, as well as neurological status and treatment-associated outcome based on the modified Rankin scale at admission, discharge and within 12 months following curative embolization, rated by an independent observer. Evidence synthesis Given the heterogeneity of the reported data, multiple confounding factors, overwhelming number of unpowered studies, lack of homogenous control groups and poor compliance to PRISMA reporting guidelines in most of the interventional literature, we were unable to obtain solid data and perform a statistical meta-analysis on the safety and effectiveness of curative embolization. Consequently, we decided to cover a selection of salient topics. Conclusions Stand-alone curative embolization, as well as exclusive microsurgery or radiosurgery each play complementary roles. Hemorrhagic, deep-seated lesions are an interesting subtype of surgically unfavorable bAVMs that may benefit from exclusive transvenous embolization, when carefully selected. Larger randomized trials and prospective registries are needed to establish the place of stand-alone or neoadjuvant endovascular treatment.

Pathophysiology of severe traumatic brain injury.

Abstract: Traumatic brain injury is a leading cause of morbidity and mortality globally, particularly among young people, with significant social and economic effects. The World Health Organization (WHO) estimates that more than five million people die each year from traumatic injuries worldwide. While public health initiatives such as seatbelts and airbags have had a major impact, it will be impossible to prevent traumatic brain injury.Therefore, it is important that we understand the pathophysiology of secondary brain injury to be able to effectively treat our patient and also to develop novel targets of future interventions. The mechanisms of secondary brain injury are complex involving alterations in cerebral perfusion, activation of inflammatory cytokines and excitotoxicity. While our understanding of these mechanisms has advanced greatly over the last decade, there is still much to learn and great uncertainty at the bedside. There has been some recent success with the discovery of some simple interventions that can reduce secondary brain injury and improve outcomes in patients after traumatic brain injury. In this review we summarize the current understanding of mechanisms and pathophysiology of primary and secondary brain injury, the goals for current treatment and potential targets for future therapy.

Epidemiology, molecular classification and WHO grading of ependymoma.

Abstract: Ependymoma can arise throughout all compartments of the central nervous system with prevalence for intracranial and spinal location in children and adults, respectively. The current histopathology based WHO grading system distinguishes grade I, II 'classic', and III 'anaplastic' ependymoma. However, analysis of multiple cohorts of intracranial ependymoma demonstrate a wide variance in the utility of the grade II versus grade III distinction as a prognostic marker that may additionally be confounded by the anatomic compartment. Recent (epi)genomic profiling efforts have identified molecularly distinct groups of ependymoma arising from all three anatomic compartments of the central nervous system that outperform the current histopathological classification regarding clinical associations. These advances have led to the cognition that molecular classification should be part of all future clinical trials in ependymoma patients. Clinical management of intracranial ependymomas (WHO Grade II/III) is challenging and molecular classification based risk stratification may help to intensify treatment and surveillance in high-risk patients but to de-escalate therapy in certain patient groups at low risk for recurrence. Finally, experience of neurosurgeons, and other disciplines, as well as intensified co-operation between all stakeholders involved hold promise to finally improve outcome of patients affected with ependymoma.

The limits of the endoscopic endonasal transclival approach for posterior fossa tumors.

Abstract: Endoscopic endonasal approaches (EEA) have gained popularity and acceptance in skull base surgery over the last two decades. So-called expanded EEA allow access in the sagittal plane from the frontal sinus to the odontoid process. The endoscopic endonasal transclival approach allows a unique trajectory into the midline clivus and skull base that is unachievable from traditional craniotomy approaches to lesions such as chondrosarcomas, chordomas, and posterior fossa meningiomas. In this review, we will assess the benefits and drawbacks to using an endoscopic endonasal approach versus transcranial approach to these challenging lesions, assess the anatomical limits of endoscopic endonasal transclival surgery, and discuss the published literature on the topic.

Minimally invasive tubular retractor-assisted biopsy and resection of subcortical intra-axial gliomas and other neoplasms.

Abstract: Background Deep-seated, subcortical tumors represent a surgical challenge. The traditional approach to these lesions involve large craniotomies, fixed retractor systems, and extensive white matter dissection, each with their own associated morbidity. We describe our experience with the use of tubular retractors for accessing these deep-seated lesions. Methods Fifty consecutive patients operated on for an intra-axial brain tumor (both biopsies and resection) from January 2016 to December 2017 by a single surgeon using tubular retractors with exoscopic visualization were prospectively identified and included in this consecutive case series. Results Thirty-five patients (70%) underwent surgical resection and 15 (30%) underwent excisional biopsy for tumors located a median (interquartile range [IQR]) distance of 5.4 (4.5-6.1) cm below the cortical surface within the thalamus and/or basal ganglia in 12 (24%), centrum semiovale in 17 (34%), cerebellar in 8 (16%), peri-Rolandic in 6 (12%), visual tracts in 5 (10%), and intraventricular in 2 (4%). The median IQR percent resection was 100 (95-100)% and all patients had diagnostic tissue. Pathology was high grade glioma in 30 (60%), metastatic in 14 (28%), and cavernoma in 2 (4%). The postoperative median IQR KPS was 80 (80-90), where 18 (36%) had improved, 29 (58%) stable, and 3 (6%) worsened KPS as compared to preoperatively. Conclusions The tubular retractor is a useful tool in the armamentarium of brain tumor surgery, and the exoscope provides an ergonomic means of visualizing the surgical field. It is meant to be used as a tool to access and resect deep-seated lesions while preserving and displacing superficial white matter tracts and cortical regions, provide a protected corridor to minimize inadvertent tissue injury during the resection, and circumferential tissue retraction to minimize risk of ischemia and damage to white matter tracts. As with any procedure, there is a learning curve with this surgical adjunct.

Monitoring the injured brain.

Abstract: Traumatic brain injury can be defined as the most complex disease in the most complex organ. When an acute brain injury occurs, several pathophysiological cascades are triggered, leading to further exacerbation of the primary damage. A number of events potentially occurring after TBI can compromise the availability or utilization of energy substrates in the brain, ultimately leading to brain energy crisis. The frequent occurrence of secondary insults in the acute phase after TBI, such as intracranial hypertension, hypotension, hypoxia, hypercapnia, hyperthermia, seizures, can then increase cerebral damage, and adversely affect outcome. Neuromonitoring techniques provide clinicians and researchers with a mean to detect and reverse those processes that lead to this energy crisis, especially ischemic processes, and have become a critical component of modern neurocritical care. Which is the best way to monitoring the brain after an acute injury has been a matter of debate for decades. This review will discuss how monitoring the injured brain can reduce secondary brain damage and ameliorate outcome after acute brain injury.

Association between carotid artery tortuosity and carotid dissection: a case-control study.

Abstract: Background Carotid artery dissections have long been associated with compromise of the structural integrity of the arterial wall from heritable connective-tissue disorders, hypertension, and trauma. However, an association between spontaneous internal carotid artery dissection and tortuous or redundant carotid anatomy has not been fully explored. Methods Patients with CTA confirmed spontaneous cervical internal carotid artery dissections were compared to a group of age and sex matched controls who also received CTA of the neck. Patients with trauma or aortic dissections were excluded. Five radiologists reviewed the CTA images to evaluate internal carotid artery tortuosity (reported as loops, kinks or coils), retrojugular and retropharyngeal courses of the internal carotid artery, presence of fibromuscular dysplasia and presence of atherosclerotic disease. Baseline data collected included demographic characteristics (sex, age, smoking history) and cardiovascular comorbidities. Results A total of 83 cervical internal carotid artery dissection and their age and sex matched controls were included in this study. 46% of patients were female in each group and mean age was 49.2±10.6 years. The presence of any carotid tortuosity was 53% (N.=44) and 34% (N.=28) in the per-patient analysis of dissection and control groups, respectively (P=0.02). Loops were reported in 22% (N.=18) of dissection patients and 8% (N.=7) of controls (P=0.03). Retrojugular course of the internal carotid artery were seen in 23% (N.=38) of dissection patients and 9% (N.=15) of controls (P=0.0009) in the per-vessel analysis. Conclusions Our study suggests that there is an association between the presence of tortuous carotid artery anatomy and spontaneous carotid artery dissection. This finding emphasizes the importance of the presence of tortuous arteries on CTA imaging to increase the index of suspicion for a potential dissection.

Utilization of intraoperative confocal laser endomicroscopy in brain tumor surgery.

Abstract: Precise identification of tumor margins is of the utmost importance in neuro-oncology. Confocal microscopy is capable of rapid imaging of fresh tissues at cellular resolution and has been miniaturized into handheld probe-based systems suitable for use in the operating room. We aimed to perform a literature review to provide an update on the current status of confocal laser endomicroscopy (CLE) technology for brain tumor surgery. Aside from benchtop confocal microscopes used in ex vivo fashion, there are four CLE systems that have been investigated for potential application in the workflow of brain tumor surgery. Preclinical studies on animal tumor models and clinical studies on human brain tumors have assessed in vivo and ex vivo imaging approaches, suggesting that confocal microscopy holds promise for rapid identification of the characteristic (diagnostic) histological features of tumor and normal brain tissues. However, there are few studies assessing diagnostic accuracy sufficient to provide a definitive determination of the clinical and economical value of CLE in brain tumor surgery. Intraoperative real-time, high-resolution tissue imaging has significant clinical potential in the field of neuro-oncology. CLE is an emerging imaging technology that shows promise for improving brain tumor surgery workflow in in vivo and ex vivo studies. Future clinical studies are necessary to demonstrate clinical and economic benefit of CLE.

Improvement in mood, oxidative stress, fatigue, and insomnia following supplementary management with Robuvit®.

Abstract: BACKGROUND Oxidative stress (OS) plays a substantial role in inflammatory and neurodegenerative diseases, causing cellular damage and mitochondrial dysfunction. OS also contributes to aging and severe neural disorders such as Alzheimer's and Parkinson's diseases. Previous registries have documented a reduction in OS levels with Robuvit® (Horphag Research, Ltd.), an extract from wood of the French oak (Quercus robur) that provides a decrease of OS as well as relief from chronic fatigue syndrome. The aim of the present registry was to investigate the influence of Robuvit® on a group of subjects presenting with mood disorders, oxidative stress, fatigue, and insomnia. METHODS Forty patients were recruited from a selection of patients with high OS levels as assessed with the d-ROMs test. Twenty-two subjects formed the control group following the standard management plan. The remaining 18 subjects formed the Robuvit® supplementation group. They received three capsules of Robuvit® 100 mg per day, for 8 weeks. RESULTS Tolerability to the supplementation with Robuvit® was overall good, and no safety concerns were raised. Mood tests showed a significant general improvement in 13 out of 16 items of the BMIS (P<0.05) in the active treatment group. Oxidative stress levels decreased significantly with Robuvit® supplementation after 4 and 8 weeks. Fatigue and insomnia score were also significantly better in supplemented subjects (P<0.05). No changes were observed in controls. CONCLUSIONS The observed decrease in OS levels in our patients is probably the result of the antioxidative activity of Robuvit®, and, more precisely, of its active metabolites, the urolithins and ellagic acid.

Septic complication following porous hydroxyapatite cranioplasty: prosthesis retention management.

Abstract: After failing of autologous cranioplasty or when the bone flap is unavailable, the alloplastic (heterologous) materials are the choice for cranial reconstruction. No agreement has been reported about the material with a significant lower risk of septic complications. This is due to extremely heterogeneous prognostic factors related not only to the material used but also to the surgical procedures and/or to the timing of the procedure. More attention should be focused on the material whose characteristic could enable a delay in bacterial colonization, where an antibiotic therapy could be effective, without need of prosthesis removal. Four cases of severe septic complication following cranioplasty with porous hydroxyapatite (HA) prosthesis are presented. Patients were conservatively treated, without heterologous bone flap removal. All of our patients presented reasons for delaying HA cranioplasty removal: patients #1, 3, and 4 had an associated shunted hydrocephalus and the need for not removing the prosthesis was related to the predictable recurrence of overshunting and/or sinking skin flap syndrome. In patient #4, the revision surgery would have also damaged the microvascular flap with latissimus dorsi muscle used by plastic surgeon for skin reconstruction. In patient #2, the patient refused revision surgery. In all cases, systemic and/or radiological signs of infection were observed. In patient #2 the infective process surrounded completely the HA prosthesis, while it was located in the epidural region in patients #1 and 4. In patient #3, a surgical curettage of the infected wound was performed over the HA prosthesis. Following prosthesis retention management with antibiotic therapy, all patients revealed systemic and/or radiological signs of sepsis resolution at follow-up. The possibility to avoid a prosthesis removal with effective antibiotic treatment is mainly due to the combination of three factors: targeted antibiotic therapy, good anatomical area revascularization (resulting of an "in situ" intake of antibiotics), and the biomimetism of HA prosthesis. Further investigations in a larger number of cases need to confirm these observations.

Endoscopic skull base surgery: evaluation of current clinical outcomes.

Abstract: Endoscopic skull base surgery is one of the most recent fields of neurosurgery. Successive innovations were developed throughout history so that the current concepts that rule this surgical field could be reached. The current paper presents the evolution of endoscopic surgery and its current results on the treatment of skull base tumor, based on a review of meta-analysis and clinical series. A PubMed search for articles published between January 1990 and January 2014 about "endoscopic skull base surgery", "endoscopic transsphenoidal approach", "endoscopic treatment of parasellar tumors" and "suprasellar lesions" was performed. According to the current data, endoscopic surgery seems to be superior to open and transsphenoidal microscopic removal of giant pituitary adenomas. Endoscopy is at least as successful as transsphenoidal microsurgery for the removal of pituitary adenomas and craniopharyngiomas. Transcranial open approaches, in the context of anterior midline skull base meningiomas, present higher rates of gross total resection, fewer complications and better clinical results than endoscopy approaches. The rate of postoperative CSF leakage has been significantly reduced with the introduction of new techniques such as the Hadad-Bassagasteguy flap but still represent one of the most important complications of this technique. Currently, selected tumors located at the anterior, middle and posterior fossa can be adequately assessed using the endoscope with low rates of postoperative CSF leaks. Endoscopic surgery has substantially evolved in the last decades through the collaboration of different teams around the world. The endoscope is now an essential tool in the neurosurgery armamentarium with great potential for new applications in the nearby future.

Limits of endoscopic endonasal transpterygoid approach to cavernous sinus and Meckel's cave.

Abstract: The endoscopic endonasal approach (EEA) to the ventral skull base has greatly increased in popularity over the last two decades. So-called expanded EEA have opened corridors to pathology off-midline, including lesions within the cavernous sinus and Meckel's cave. A standard EEA exposure into the sphenoid sinus allows visualization of the medial cavernous sinus; a transpterygoid approach allows for surgical manipulation of the lateral cavernous sinus and Meckel's cave contents. Pituitary adenomas, meningiomas, and schwannomas are the most common pathologies in this region. This approach to the "front door" of the cavernous sinus and Meckel's cave should be considered complementary to traditional craniotomy techniques as each have benefits and limitations. Herein we review the published literature regarding endoscopic endonasal transpterygoid surgery for pathology in the lateral cavernous sinus and Meckel's cave, and the anatomical and functional limitations of these approaches.

Technology-assisted rehabilitation interventions following pediatric brain injury.

Abstract: INTRODUCTION Following traumatic brain injury (TBI), children experience a variety of physical, motor, speech, and cognitive deficits that can have a long-term detrimental impact The emergence and popularity of new technologies has led to research into the development of various apps, gaming systems, websites, and robotics that might be applied to rehabilitation The objective of this narrative review was to describe the current literature regarding technologically-assisted interventions for the rehabilitation of motor, neurocognitive, behavioral, and family impairments following pediatric TBI EVIDENCE ACQUISITION We conducted a series of searches for peer-reviewed manuscripts published between 2000 and 2017 that included a technology-assisted component in the domains of motor, language/communication, cognition, behavior, social competence/functioning, family, and academic/school-based functioning EVIDENCE SYNTHESIS Findings suggested several benefits of utilizing technology in TBI rehabilitation including facilitating engagement/adherence, increasing access to therapies, and improving generalizability across settings There is fairly robust evidence regarding the efficacy of online family problem-solving therapy in improving behavior problems, executive functioning, and family functioning There was less compelling, but still promising, evidence regarding the efficacy other technology for motor deficits, apps for social skills, and computerized programs for cognitive skills Overall, many studies were limited in the rigor of their methodology due to small heterogeneous samples and lack of control groups CONCLUSIONS Technology-assisted interventions have the potential to enhance pediatric rehabilitation after TBI Future research is needed to further support their efficacy with larger controlled trials and to identify characteristics of children who are most likely to benefit

Endoscopic endonasal transpterygoid approach to petrous pathologies: technique, limitations and alternative approaches.

Abstract: The endoscopic endonasal transpterygoid approach is a versatile technique, providing direct access to the petrous apex through an anterior surgical corridor. In this review we detail the transpterygoid approach to the petrous apex and highlight its relative indications. Although this approach is a useful strategy for many lesions of the petrous apex, disease extension into lateral, superior, or posterior compartments may limit extent of resection afforded by an anterior approach alone. Based on these considerations, a disease compartment-specific strategy is discussed. The limitations of the transpterygoid approach and indications for lateral and postero-lateral approaches to petrous pathology are reviewed.

Limits of endoscopic endonasal surgery for III ventricle craniopharyngiomas.

Abstract: Craniopharyngiomas represent one of the most challenging brain tumors for the neurosurgeon. For most of the 20th century, these parasellar lesions have been approached via the classic open approaches of neurosurgery such as pterional, frontobasal, interhemispheric, and transpetrosal craniotomies. The endoscopic endonasal approach to these tumors, rather than craniotomy, has risen in popularity over the last two decades. Regardless of approach, a detailed knowledge of surgical anatomy and careful preoperative surgical planning are essential to achieve good clinical results; iatrogenic morbidity can potentially be severe due to hypothalamus, optic apparatus, and/or vascular injuries. Especially challenging, and highlighting the limitations of endoscopic endonasal surgery, are the tumors that arise primarily from within the third ventricle and do not expand the pituitary stalk and suprasellar region or tumors that have projected to areas far from the parasellar region as such as the sylvian and ambient cisterns. Herein we review the published literature regarding endoscopic endonasal surgery for craniopharyngioma, and the anatomical and functional limitations therein. The benefits and drawbacks of each surgical approach to this deep-seated area are discussed, and a strategy for surgical decision-making proposed.

The limits of transsellar/transtuberculum surgery for craniopharyngioma.

Abstract: The proximity of craniopharyngiomas to vital neurovascular structures and their high recurrence rates make them one of the most challenging brain tumors to treat. Although surgery remains the first line of therapy and offers the best chance of radical resection and oncological cure, the high recurrence tendency of craniopharyngiomas, even after apparent total removal, often makes adjuvant treatment essential. The endoscopic endonasal approach (EEA) has been recently introduced as a treatment option for both pediatric and adult craniopharyngiomas, rapidly gaining wide acceptance over the traditional transcranial approaches. Although the primary role of EEA over traditional transcranial approaches has been slowly accepted in the literature, little has been written about the limitations and potential contraindications of this approach in the treatment of craniopharyngiomas. This article presents the advantages and highlights the limitations of endoscopic transsellar/transtuberculum surgery for craniopharyngiomas. In every case, surgery should be tailored to individuals based on their age and comorbidities, presenting symptoms, tumor characteristics, prior treatment and treatment tolerance, as well as the surgeon's preference based on personal experience and comfort.

Elevated brain derived neurotrophic factor levels in plasma reflect in vivo functional viability of infused mesenchymal stem cells for stroke in rats.

Abstract: Background Intravenous infusion of mesenchymal stem cells (MSCs) derived from adult bone marrow elicits functional recovery in rat stroke models and clinical studies in patients are ongoing. Brain derived neurotrophic factor (BDNF) is a neurotrophic factor produced by MSCs and may contribute to their therapeutic efficacy. The purpose of the current study was to determine if BDNF is elevated in infarcted brain and in which compartment of blood (plasma or serum) after intravenous MSC infusion in a middle cerebral artery occlusion (MCAO) model in the rat. Methods In rats, a permanent middle cerebral artery occlusion (MCAO) was induced by intraluminal vascular occlusion with a microfilament and MSCs were intravenously administered 6 h after right MCAO induction. Enzyme-linked immunosorbent assay (ELISA) analysis of brain, serum and plasma BDNF were performed after the MSC infusion following the MCAO induction. Lesion volume was assessed using magnetic resonance imaging. Functional outcome was assessed using the Limb Placement Test. Results Infused MSCs reduced lesion volume and elicited functional improvement compared to the vehicle infused group. ELISA analysis of the MSC treated group revealed an increase BDNF levels in the infarcted hemisphere of the brain and plasma, but not in serum. The MSC group showed a greater increase in BDNF levels than sham control. In the MSC group, the expression of increased plasma BDNF levels correlated with increased brain BDNF levels. Conclusions These results support the hypothesis that BDNF levels in plasma, but not serum, may be more appropriate to detect circulating BDNF in vivo following MSC infusion in a cerebral infarction rat model of ischemic stroke. Further, plasma BDNF might reflect in vivo functional viability of infused MSCs after stroke.

Fractional anisotropy to quantify cervical spondylotic myelopathy severity.

Abstract: Background A number of clinical tools exist for measuring the severity of cervical spondylotic myelopathy (CSM). Several studies have recently described the use of non-invasive imaging biomarkers to assess severity of disease. These imaging markers may provide an additional tool to measure disease progression and represent a surrogate marker of response to therapy. Correlating these imaging biomarkers with clinical quantitative measures is critical for accurate therapeutic stratification and quantification of axonal injury. Methods Fourteen patients and seven healthy control subjects were enrolled. Patients were classified as mildly (7) or moderately (7) impaired based on Modified Japanese Orthopedic Association Scale. All patients underwent diffusion tensor imaging (DTI) and diffusion basis spectrum imaging (DBSI) analyses. In addition to standard neurological examination, all participants underwent 30-m Walking Test, 9-hole Peg Test (9HPT), grip strength, key pinch, and vibration sensation thresholds in the index finger and great toe. Differences in assessment scores between controls, mild and moderate CSM patients were correlated with DTI and DBSI derived fractional anisotropy (FA). Results Clinically, 30-meter walking times were significantly longer in the moderately impaired group than in the control group. Maximum 9HPT times were significantly longer in both the mildly and moderately impaired groups as compared to normal controls. Scores on great toe vibration sensation thresholds were lower in the mildly impaired and moderately impaired groups as compared to controls. We found no clear evidence for any differences in minimum grip strength, minimum key pinch, or index finger vibration sensation thresholds. There were moderately strong associations between DTI and DBSI FA values and 30-meter walking times and 9HPT. Conclusions The 30-m Walking Test and 9HPT were both moderately to strongly associated with DTI/DBSI FA values. FA may represent an additional measure to help differentiate and stratify patients with mild or moderate CSM.

Minimally invasive endoscopic-assisted approaches to the posterior fossa.

Abstract: Modern surgical approaches are becoming more minimalistic, associated with the term "minimally invasive." The endoscope provides a more panoramic anatomical view in addition to the ability to access narrow deep corners with decent illumination and clear visualization. Endoscopic assisted microsurgery through a tailored small craniotomy is the foundation of keyhole surgery. The endoscope can be advanced deeper into the field, thus enhancing an exposure and allowing bimanual dissection, ultimately providing smaller craniotomies and tailored key exposures. The term "minimally invasive" became associated with reduction of overall tissue injury, decreased potential complications, reduced recovery times/hospital stay, and overall reduced costs. This minimally invasive concept became successfully applicable to diverse pathologies in the three cranial fossae. The posterior fossa houses the most critical neurovascular structures of the brain in an intricate and complex anatomical organization. In this manuscript, we describe keyhole endoscopic-assisted approaches to different regions of the posterior fossa. Five corridors for these approaches are described: 1) midline supracerebellar-infratentorial to the pineal region; 2) upper cerebellopontine angle (CPA) to the trigeminal region; 3) middle cerebellopontine angle to the vestibulocochlear region and internal auditory meatus; 4) inferior cerebellopontine angle to the jugular foramen region and lower cranial nerves; and 5) midline infracerebellar to posterior foramen magnum and the craniocervical junction. We then present a general review of the published literature and case examples demonstrating the effectiveness of the endoscopic-assisted keyhole concept.

Intracranial stereotactic radiosurgery.

Abstract: Stereotactic radiosurgery (SRS) is the use of a single high dose of radiation, stereotactically directed to an intracranial region of interest, in order to create a lesion or obliterate a preexisting one. This technology has evolved over the years into the use of multiple radiation sources oriented at a variety of angles, thus permitting the creation of various treatment target shapes. This allows for non-open surgical treatment of intracranial pathologies, which significantly decreases the risk of morbidity. The destruction of pathological tissue following radiosurgery is a stepwise process that involves a number of different stages, beginning with the necrotic stage, followed by the resorption stage, and concluding with the glial scar formation stage. There are currently a number of different delivery methods of SRS, including linear accelerators, Gamma Knife units, and charged particle methods (Bragg-peak and plateau-beam). Various intracranial lesions exhibit different responses to radiosurgery; however, most lesions of appropriate size tend to respond favorably. Radiosurgery is used today in the treatment of brain metastases, meningiomas, vestibular schwannomas, sellar and suprasellar lesions, and arteriovenous malformations. SRS is widely used to treat functional conditions, such as trigeminal neuralgia and intractable tremor. The treatment of intracranial lesions with radiosurgery can result in undesirable effects on the adjacent normal brain, resulting in adverse radiation effects. The distinction between tumor progression and adverse radiation effects can be challenging but is aided by various imaging modalities. Treatment options for this condition include observation, corticosteroids, pentoxifylline and vitamin E, bevacizumab, laser-interstitial thermal therapy, and surgical resection.

Current and future uses of transcranial focused ultrasound in neurosurgery.

Abstract: Focused ultrasound (FUS) produces a region of high intensity at the focal zone of the beam but with minimal effects at adjacent areas, allowing the sonication of deep targets throughout the body. Despite early obstacles to transmitting ultrasound energy through the skull, recent advances in ultrasound technology, software, and real-time monitoring have resulted in a renewed interest in the clinical applications of transcranial FUS. Following extensive pre-clinical studies, ultrasound-induced thermal ablation has been approved by several countries for the treatment of essential tremor, Parkinson's disease, obsessive-compulsive disorder, depression, and neuropathic pain. Ongoing clinical trials involving patients with brain tumors, Alzheimer's disease, or epilepsy, and pre-clinical work involving stroke and hydrocephalus have the potential to significantly expand the possible indications for transcranial FUS in the future.

Readmission after spinal cord injury: analysis of an institutional cohort of 795 patients

Abstract: BACKGROUND Recent studies in other fields have suggested that healthcare on the weekend may have worse outcomes. In particular, patients with stroke and acute cardiovascular events have shown worse outcomes with weekend treatment. It is unclear whether this extends to patients with spinal cord injury. This study was designed to evaluate factors for readmission after index hospitalization for spinal cord injury. METHODS A total of 795 consecutive patients over an 11-year period were analyzed. After excluding patients with chronic spinal cord injury and surgical care at an outside hospital, 745 patients remained. The primary outcome measure evaluated was 30-day readmission. Secondary measures include perioperative complications, readmission rate when discharged on the weekend, and the effect of race and insurance status on readmission rate. Univariate and multivariate analysis were utilized to evaluate the covariates collected. The χ2 test, Fisher's exact test, and linear and logistic regression methods were utilized for statistical analysis. RESULTS A total of 745 patients were analyzed after exclusions. Payer status did not affect length of stay, ICU length of stay, or perioperative complications. Neither weekend admission nor weekend operation affected length of stay, ICU length of stay, or readmission by 30 days. Patients undergoing weekend surgical treatment had lower perioperative complication rates (2.2% vs. 6.5% on weekday, P<0.01). Discharge on the weekend was associated with a significantly lower rate of readmission by 30 days (OR=0.07, 95% CI: 0.009-0.525, P<0.005). Payer status was associated with 30-day readmission (P<0.005). Patients with Medicare (20.8%) and Medicaid (20.1%) showed higher rates of readmission than patients with other payers. 21.1% of African-American patients were readmitted, versus 10.2% of other patients (Odds ratio: 2.2, 95% confidence interval 1.36-3.27, P<0.001). Correcting for payer status lessened but did not eliminate the effect of race on readmission. CONCLUSIONS Weekend admission did not increase perioperative complications or hospital length of stay. After discharge, patients with Medicaid and Medicare show higher rates of 30-day readmission, as do African-American patients. The effect of race on readmission is multifactorial, and may partially explained by the increased rate of Medicaid coverage in African-Americans in our institutions catchment area.

Neuroprotection in traumatic brain injury.

Abstract: Traumatic brain injury (TBI) has a high incidence worldwide and is associated with significant morbidity and mortality. TBI has enduring implications in several domains and limits overall quality of life even in the survivors. Assessment of failures of different strategies attempted at improving outcomes in traumatic brain injury is required. Several neuroprotective strategies have been studied to limit the morbidity and mortality associated with TBI. Various approaches, both pharmacologic and surgical, have been tried. In this article, we will review the epidemiology of TBI, the impact of secondary brain injury on outcomes and different strategies in traumatic brain injury. Furthermore, discussion into failure of different strategies and necessary future approach will be discussed. TBI remains a challenging condition to intervene on due to its heterogeneity. Future work should incorporate a multi-disciplinary as well as multi-center approach to target specific subset of patient population.

Predicting outcomes after severe traumatic brain injury: science, humanity or both?

Abstract: Predicting long-term outcome after severe traumatic brain injury (TBI) is difficult, but accurate assessment is paramount for both families of the patients and medical decision-making, as well as quality assurance or research purposes. Many important prognostic factors for patients with severe TBI have been identified, but most - if not all - including the Glasgow Coma Score and magnetic resonance imaging are not accurate enough to be used alone to predict patient outcomes. Clinicians should also be wary about how their predictions and decision-making can be affected by heuristics and cognitive biases. Well-validated prognostic models, including the CRASH and IMPACT models, are easily available and, provided their limitations are appreciated, they offer an enormous potential to assist clinicians to objectively prognosticate the outcomes of patients with severe TBI by reducing the unduly influence of subconscious heuristics and cognitive biases. Finally, we also should not underestimate human being’s adaptability, including their ability to recalibrate what may be acceptable to them when life circumstances have changed. Predicting outcome and decision-making after severe TBI requires a deep understanding of both science and humanity - a task we should all take seriously.

Reanalyzing the "far medial" (transcondylar-transtubercular) approach based on three anatomical vectors: the ventral posterolateral corridor.

Abstract: Endoscopic endonasal access to the jugular foramen and occipital condyle - the transcondylar-transtubercular approach - is anatomically complex and requires detailed knowledge of the relative position of critical neurovascular structures, in order to avoid inadvertent injury and resultant complications. However, access to this region can be confusing as the orientation and relationships of osseous, vascular, and neural structures are very much different from traditional dorsal approaches. This review aims at providing an organizational construct for a more understandable framework in accessing the transcondylar-transtubercular window. The region can be conceptualized using a three-vector coordinate system: vector 1 represents a dorsal or ventral corridor, vector 2 represents the outer and inner circumferential anatomical limits; in an "onion-skin" fashion, key osseous, vascular, and neural landmarks are organized based on a 360-degree skull base model, and vector 3 represents the final core or target of the surgical corridor. The creation of an organized "global-positioning system" may better guide the surgeon in accessing the far-medial transcondylar-transtubercular region, and related pathologies, and help understand the surgical limits to the occipital condyle and jugular foramen - the ventral posterolateral corridor - via the endoscopic endonasal approach.