Adverse impact of smoking on the spine and spinal surgery.

BACKGROUND: Tobacco smokers and companies are well aware that smoking increases the risks for cancers, vascular morbidity, and early mortality. This is a review of the plethora of adverse effects chronic smoking has on spinal tissues and spinal surgery. METHODS: Medline (PubMed) and Google Scholar databases were searched for pertinent literature through keywords related to smoking, spondylosis, and spinal surgery. RESULTS: Smoking accelerates spondylosis by impairing spinal tissue vascular supply through atherosclerosis and thrombosis, while inducing local hypoxia, inflammation, proteolysis, and cell loss. It, thus, compromises disc, cartilage, synovium, bone, and blood vessels. It can lead to early surgery, delayed wound healing, increased surgical site infection, failed fusion, more re-operations, and chronic spinal pain. CONCLUSION: There is ample evidence to support surgeons' declining to operate on chronic smokers. The need for immediate and permanent smoking cessation and its potential benefits should be emphasized for the patient considering or who has undergone spinal surgery.

Aerospace Implications of Key Neurological Conditions.

INTRODUCTION: The neurological impact (or lack thereof) of certain medical histories and imaging findings is important to understand in the context of air and spaceflight. There are a number of neurological conditions that, if present in pilots and astronauts, carry variable (and sometimes adverse) functional implications for safety and overall mission success. In this systematic overview, the authors will refer to the relevant clinical and radiological features of brain tumors and vascular anomalies, cerebral edema and intracranial hypertension, concussion and the traumatic brain injury (TBI) spectrum, hematomas, cerebrospinal fluid circulation anomalies including hydrocephalus and sequestrations, spinal degenerative changes, and cerebral ischemia and demyelination. It is notable that these last two conditions have recently been reported to be a complication in some people with coronavirus disease 2019 (COVID-19). A paradigm for practical neurological workup of symptomatic pilots and astronauts will be discussed, as will the controversial notion of pre-emptive radiological screening (vs. not screening) in asymptomatic or clinically occult situations. The concepts of medical surveillance in the setting of known or diagnosed pathologies, and expert panel review and simulator and flight checks in complex neurological cases, are also elaborated on in this paper. We believe this overview will contribute toward the enhancement of a broad understanding of neurological conditions, their clinical workup, and their precautionary management in the setting of aviation and aerospace.Khurana VG, Jithoo R, Barnett M. Aerospace implications of key neurological conditions. Aerosp Med Hum Perform. 2021; 92(2):113119.

Intracranial neuroenteric cysts: a concise review including an illustrative patient.

Neuroenteric cysts (NC) are rare, benign lesions lined by mucin-secreting cuboidal or columnar epithelium of an intestinal or respiratory type. They are regarded as ectopic endodermal cysts, and tend to be found in the spine rather than an intracranial location. Advances in neuroimaging have led to an increased frequency of diagnosis of NC, especially as an incidental finding, although such cysts may be confused radiologically with other lesions such as epidermoid and arachnoid cysts. We undertook a PubMed search of the literature using the search terms "neuroenteric cyst" and its many pseudonyms, including "endodermal cyst", "enterogenous cyst", "neurenteric cyst", "epithelial cyst", "intestinome", "teratomatous cyst", "gastrocytoma", and also "enterogenic", "foregut", "respiratory", and "bronchogenic cyst". Only reports in English and those containing histopathologically-confirmed NC were considered for this review. In total, 140 patients with intracranial NC were found, including the patient reported in the present review. This review describes the classification, epidemiology, embryology, clinical presentation, radiology, histopathology, and surgical treatment of NC, and includes an illustrative patient.

An overview of concussion in sport.

Concussion is a sudden-onset, transient alteration of consciousness due to a combination of functional and structural brain disturbances following a physical impact transmitted to the brain. It is a common, although likely underreported, condition encountered in a wide range of sports. In the Australian Football League, concussion is estimated to occur at a rate of approximately seven injuries per team per season. While many instances of concussion are clinically mild, there is emerging evidence that a player's full recovery from a concussive injury may be more delayed and the sequelae of repeated concussions more severe than previously thought. In this light, a more conservative and rigorous approach to managing players with concussive injuries may be warranted, with the guiding principle being the player's immediate and long-term welfare. The current paper reviews the sports concussion literature. The definition, epidemiology, aetiology, pathophysiology, structural pathology, clinical features, assessment and investigation, treatment principles, and short-term and potential long-term complications of concussion are discussed. Special considerations in paediatric sports concussion, and the return-to-play implications of immediate, evolving and repetitive brain injury are also considered, as are the emerging concept and possible implications of subconcussive injury.

A multicenter study of primary brain tumor incidence in Australia (2000-2008).

There are conflicting reports from Europe and North America regarding trends in the incidence of primary brain tumor, whereas the incidence of primary brain tumors in Australia is currently unknown. We aimed to determine the incidence in Australia with age-, sex-, and benign-versus-malignant histology-specific analyses. A multicenter study was performed in the state of New South Wales (NSW) and the Australian Capital Territory (ACT), which has a combined population of >7 million with >97% rate of population retention for medical care. We retrospectively mined pathology databases servicing neurosurgical centers in NSW and ACT for histologically confirmed primary brain tumors diagnosed from January 2000 through December 2008. Data were weighted for patient outflow and data completeness. Incidence rates were age standardized and trends analyzed using joinpoint analysis. A weighted total of 7651 primary brain tumors were analyzed. The overall US-standardized incidence of primary brain tumors was 11.3 cases 100 000 person-years (±0.13; 95% confidence interval, 9.8-12.3) during the study period with no significant linear increase. A significant increase in primary malignant brain tumors from 2000 to 2008 was observed; this appears to be largely due to an increase in malignant tumor incidence in the ≥65-year age group. This collection represents the most contemporary data on primary brain tumor incidence in Australia. Whether the observed increase in malignant primary brain tumors, particularly in persons aged ≥65 years, is due to improved detection, diagnosis, and care delivery or a true change in incidence remains undetermined. We recommend a direct, uniform, and centralized approach to monitoring primary brain tumor incidence that can be independent of multiple interstate cancer registries.

The experience of patients undergoing awake craniotomy for intracranial masses: expectations, recall, satisfaction and functional outcome.

Introduction. Awake craniotomy is a well-established neurosurgical technique for lesions involving eloquent cortex, however, there is little information regarding patients' subjective experience with this type of surgery. Here we explore the expectations, recall, satisfaction and functional outcome of patients undergoing awake craniotomy. Methods. Three semi-structured interviews using closed- and open-ended questions were conducted with each of 26 consecutive patients (17 males, 9 females; aged 16-78 years) who underwent their first awake craniotomy between 2007 and 2009. Seven patients were interviewed retrospectively, 19 prospectively. Clinical data are included. Results. The following themes emerged from this study: (1) most patients demonstrated a good understanding of the rationale behind awake craniotomy; (2) patients felt the asleep-awake-asleep anaesthetic protocol used in this series was appropriate; (3) patients' confidence and preparedness for surgery was high, attributed to preparation by the surgical team. Seven of 26 (27%) patients had no recollection of being awake. Most patients had a positive anaesthetic and surgical experience, while a minority of patients reported experiencing more than slight pain (2/26; 8%) and discomfort (3/26; 12%), fear (4/26; 15%) or claustrophobia (1/26; 4%) intra-operatively. At follow-up (6 weeks post-operatively), most patients were functionally unimpaired; there was only one permanent neurological complication of surgery. We found that 24/26 (92%) patients were satisfied with their experience; one patient had no opinion and another one was unsatisfied. Five of 26 (19%) patients still reported more than slight discomfort, and 3/26 (12%) reported more than slight pain attributable to the surgery. A summary of the English peer-reviewed literature on the patient experience of awake craniotomy is also incorporated. Conclusions. This study confirms that awake craniotomy using the 'asleep-awake-asleep' anaesthetic protocol is a generally safe and well-tolerated procedure associated overall with satisfactory patients' experiences and neurological outcomes.

Increasing incidence of glioblastoma multiforme and meningioma, and decreasing incidence of Schwannoma (2000-2008): Findings of a multicenter Australian study.

BACKGROUND: The incidence of primary brain tumors by subtype is currently unknown in Australia. We report an analysis of incidence by tumor subtype in a retrospective multicenter study in the state of New South Wales (NSW) and the Australian Capital Territory (ACT), with a combined population of >7 million with >97% retention rate for medical care. METHODS: Data from histologically confirmed primary brain tumors diagnosed from January 2000 through December 2008 were weighted for patient outflow and data completeness, and age standardized and analyzed using joinpoint analysis. RESULTS: A significant increasing incidence in glioblastoma multiforme (GBM) was observed in the study period (annual percentage change [APC], 2.5; 95% confidence interval [CI], 0.4-4.6, n = 2275), particularly after 2006. In GBM patients in the ≥65-year group, a significantly increasing incidence for men and women combined (APC, 3.0; 95% CI, 0.5-5.6) and men only (APC, 2.9; 95% CI, 0.1-5.8) was seen. Rising trends in incidence were also seen for meningioma in the total male population (APC, 5.3; 95% CI, 2.6-8.1, n = 515) and males aged 20-64 years (APC, 6.3; 95% CI, 3.8-8.8). Significantly decreasing incidence trends were observed for Schwannoma for the total study population (APC, -3.5; 95% CI, -7.2 to -0.2, n = 492), significant in women (APC, -5.3; 95% CI, -9.9 to -0.5) but not men. CONCLUSION: This collection is the most contemporary data on primary brain tumor incidence in Australia. Our registries may observe an increase in malignant tumors in the next few years that they are not detecting now due to late ascertainment. We recommend a direct, uniform, and centralized approach to monitoring primary brain tumor incidence by subtype, including the introduction of nonmalignant data collection.

Epidemiological evidence for a health risk from mobile phone base stations.

Human populations are increasingly exposed to microwave/radiofrequency (RF) emissions from wireless communication technology, including mobile phones and their base stations. By searching PubMed, we identified a total of 10 epidemiological studies that assessed for putative health effects of mobile phone base stations. Seven of these studies explored the association between base station proximity and neurobehavioral effects and three investigated cancer. We found that eight of the 10 studies reported increased prevalence of adverse neurobehavioral symptoms or cancer in populations living at distances < 500 meters from base stations. None of the studies reported exposure above accepted international guidelines, suggesting that current guidelines may be inadequate in protecting the health of human populations. We believe that comprehensive epidemiological studies of long-term mobile phone base station exposure are urgently required to more definitively understand its health impact.

Intuitiveness, quality and utility of intraoperative fluorescence videoangiography: Australian Neurosurgical Experience.

INTRODUCTION: The authors have undertaken a study of their intraoperative experience with indocyanine green fluorescence videoangiography (ICGFV). In particular, the intuitiveness, image quality and clinical utility of this technology have been assessed. METHODS: The records of forty-six consecutive craniotomies utilising ICGFV have been retrospectively reviewed: There were 27 aneurysms, 2 extracranial-intracranial (EC-IC) bypasses, 5 arteriovenous malformations (AVM), 1 dural arteriovenous fistula (DAVF), 3 cavernomas, 5 meningiomas, and 3 gliomas. ICGFV was used in 5 awake-craniotomy patients. ICGFV was performed using a Leica OH4 surgical microscope with integrated near-infrared camera and ICG-PULSION. RESULTS: All attempts of intraoperative ICGFV were intuitive. Image quality and resolution were excellent. Arterial and venous phases were comparable to digital subtraction angiography (DSA) but field of view was relatively limited. In 12 operations (26%) the surgeon was substantially benefited from ICGFV findings. In 22 operations (48%), ICGFV was useful but did not influence surgical management. ICGFV was of no benefit in 11 operations (24%) and was misleading in 1 (2%). In this series, ICGFV was of benefit to 1 of 11 (9%) patients with an intracranial neoplasm or cavernoma. CONCLUSIONS: ICGFV is safe, intuitive and provides neurosurgeons with high quality, valuable, real-time imaging of cerebrovascular anatomy. It can assist in intraoperative surgical management and/or stroke prevention particularly during aneurysm clipping, EC-IC bypass and AVM/DAVF surgery.

Cell phones and brain tumors: a review including the long-term epidemiologic data.

BACKGROUND: The debate regarding the health effects of low-intensity electromagnetic radiation from sources such as power lines, base stations, and cell phones has recently been reignited. In the present review, the authors attempt to address the following question: is there epidemiologic evidence for an association between long-term cell phone usage and the risk of developing a brain tumor? Included with this meta-analysis of the long-term epidemiologic data are a brief overview of cell phone technology and discussion of laboratory data, biological mechanisms, and brain tumor incidence. METHODS: In order to be included in the present meta-analysis, studies were required to have met all of the following criteria: (i) publication in a peer-reviewed journal; (ii) inclusion of participants using cell phones for > or = 10 years (ie, minimum 10-year "latency"); and (iii) incorporation of a "laterality" analysis of long-term users (ie, analysis of the side of the brain tumor relative to the side of the head preferred for cell phone usage). This is a meta-analysis incorporating all 11 long-term epidemiologic studies in this field. RESULTS: The results indicate that using a cell phone for > or = 10 years approximately doubles the risk of being diagnosed with a brain tumor on the same ("ipsilateral") side of the head as that preferred for cell phone use. The data achieve statistical significance for glioma and acoustic neuroma but not for meningioma. CONCLUSION: The authors conclude that there is adequate epidemiologic evidence to suggest a link between prolonged cell phone usage and the development of an ipsilateral brain tumor.

Update on evidence for a genetic predisposition to cerebral vasospasm.

Considerable evidence links cerebral vasospasm to the decreased bioavailability of endothelial nitric oxide synthase (eNOS) after aneurysmal subarachnoid hemorrhage (SAH). In recent studies from the cardiology literature, researchers have suggested that a genetic predisposition to coronary vasospasm might develop as the result of a T-786C single nucleotide polymorphism (SNP) in the eNOS gene. The authors of this study attempted to determine if there may be a similar genetic predisposition toward cerebral vasospasm. The authors prospectively identified 28 patients with Fisher Grade 3 SAH from a group of 51 consecutive patients with ruptured intracranial saccular aneurysms. Genomic DNA was isolated from a peripheral blood sample obtained with permission from each patient. Gene microarray technology was used to assay the samples for the presence and distribution of certain key eNOS gene polymorphisms. Clinical, radiological, and genomic data were analyzed. The finding of eNOS T-786C SNP could be used to significantly differentiate between the presence and severity of cerebral vasospasm (p = 0.04). The findings from this preliminary study support similar findings in the coronary vasospasm literature as well as the hypothesis that a predisposition toward cerebral vasospasm may be related partially to genetic factors, which needs to be confirmed in a larger study. Such gene-based information may be important in rapidly identifying patients at increased risk of vasospasm after SAH, independent of their Fisher grade. In this article, the authors review key studies in this area.

Intraoperative rupture of brainstem cavernous malformation. Case report.

Although cavernous malformations (CMs) are an important cause of intracranial hemorrhage, the natural history of these lesions is controversial. Both retrospective and prospective studies undertaken to define risk factors for hemorrhage from CMs have consistently identified the location of a lesion as a factor that has a significant impact on the rate of rupture, and brainstem CMs consistently have a higher rate of symptomatic hemorrhage than those at other locations. The mechanism underlying this disparity in rupture rates, however, remains obscure. Most authors attribute the difference, at least partially, to the sensitivity of the brainstem to hemorrhage. Regardless, the specific factors that cause a given CM to rupture are unknown. The authors report their first encounter with an intraoperative rupture of a CM in the brainstem. This case underscores the risks encountered during the surgical approach to brainstem CMs and may provide insight into the pathophysiological mechanisms underlying the rupture of these lesions.

The presence of tandem endothelial nitric oxide synthase gene polymorphisms identifying brain aneurysms more prone to rupture.

OBJECT: It is becoming apparent that the presence of certain genetic variations (polymorphisms) may increase the individual's susceptibility to cardiovascular diseases, even in the absence of a family history. We hypothesized that brain aneurysms more prone to rupture may be identified on the basis of an individual's genotype for endothelial nitric oxide synthase (eNOS), a critical vasomodulatory protein found to be increasingly relevant to the pathobiology of aneurysms. METHODS: Patients' clinical data were recorded prospectively. Genomic DNA was isolated from blood samples obtained from individuals presenting consecutively to the Mayo Clinic with ruptured (58 patients) or unruptured (49 patients) intracranial saccular aneurysms. Using polymerase chain reaction and gene microarray technology, the following eNOS genetic polymorphisms were studied: intron-4 27-base pair variable number of tandem repeats (27 VNTR); promoter single nucleotide polymorphism (T-786C SNP); and exon-7 SNP (G894T SNP). Both groups of patients had similar demographic and clinical characteristics. For all three polymorphisms, variant alleles (p < or = 0.003) and their corresponding genotypes (p < or = 0.006) were found two to four times more frequently in patients with ruptured aneurysms than in patients with unruptured aneurysms. Strikingly, the odds ratio for presenting with a ruptured brain aneurysm among individuals demonstrating the copresence of all three variant alleles was 11.4 (95% confidence interval 1.7-75.9, p = 0.004). CONCLUSIONS: The authors have uniquely identified a set of tandem eNOS gene variations whose presence can be used to identify patients with aneurysms likely to rupture. We believe that if this finding is reproducible in a large multicenter study, in addition to known anatomical factors a rapid and cost-effective screening tool will become available to clinicians as a genetic aid to predict the risks of rupture in patients presenting with unruptured intracranial aneurysms.