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Most patients with World Federation of Neurological Surgeons (WFNS) grade 5 subarachnoid hemorrhage (SAH) have poor outcomes. Accurate assessment of prognosis is important for treatment decisions and conversations with families regarding goals of care. Unjustified pessimism may lead to “self-fulfilling prophecy,” where withdrawal of life-sustaining measures (WLSM) is invariably followed by death.
We performed a cohort study involving consecutive patients with WFNS grade 5 SAH to identify variables with >= 90% and >= 95% positive predictive value (PPV) for poor outcome (1-year modified Rankin Score >= 4), as well as findings predictive of WLSM.
Of 140 patients, 38 (27%) had favorable outcomes. Predictors with >= 95% PPV for poor outcome included unconfounded 72-hour Glasgow Coma Scale motor score <= 4, absence of >= 1 pupillary light reflex (PLR) at 24 hours, and intraventricular hemorrhage (IVH) score of >= 20 (volume >= 54.6 ml). Intracerebral hemorrhage (ICH) volume >= 53 ml had PPV of 92%. Variables associated with WLSM decisions included a poor motor score (p < 0.0001) and radiographic evidence of infarction (p = 0.02).
We identified several early predictors with high PPV for poor outcome. Of these, lack of improvement in motor score during the initial 72 hours had the greatest potential for confounding from “self-fulfilling prophecy.” Absence of PLR at 24 hours, IVH score >= 20, and ICH volume >= 53 ml predicted poor outcome without a statistically significant effect on WLSM decisions. More research is needed to validate prognostic variables in grade 5 SAH, especially among patients who do not undergo WLSM.
Background: The proposed implementation of work hour restrictions has presented a significant challenge of maintaining the quality of resident education and ensuring adequate hands-on experience that is essential for novice surgeons. To maintain the level of resident surgical competency, revision of the apprentice model of surgical education to include supplementary educational methods, such as laboratory and virtual reality (VR) simulations, have become frequent topics of discussion. We aimed to better understand the role of supplementary educational methods in Canadian neurosurgery residency training. Methods: An online survey was sent to program directors of all 14 Canadian neurosurgical residency programs and active resident members of the Canadian Neurosurgical Society (N=85). We asked 16 questions focusing on topics of surgeon perception, current implementation and barriers to supplementary educational models. Results: Of the 99 surveys sent, 8 out of 14 (57%) program directors and 37 out of 85 (44%) residents completed the survey. Of the 14 neurosurgery residency programs across Canada, 7 reported utilizing laboratory-based teaching within their educational plan, while only 3 programs reported using VR simulation as a supplementary teaching method. The biggest barriers to implementing supplementary educational methods were resident availability, lack of resources, and cost. Conclusions: Work-hour restrictions threaten to compromise the traditional apprentice model of surgical training. The potential value of supplementary educational methods for surgical education is evident, as reported by both program directors and residents across Canada. However, availability and utilization of laboratory and VR simulations are limited by numerous factors such as time constrains and lack of resources.
Complex cerebral aneurysms may require indirect treatment with revascularization. This manuscript describes various surgical revascularization techniques together with clinical outcomes.
Thirty-two consecutive patients with complex cerebral aneurysm were managed from November 2005 to October 2008. Techniques used for revascularization were high-flow bypass, low-flow bypass, branch artery reimplantion, and primary reanastomosis. Physiologic and anatomic monitoring technologies, including electroencephalography, somatosensory evoked potential monitoring, microvascular doppler ultrasonography, and/or indocyanine green videoangiography were used intraoperatively to assess both brain physiology and vascular anatomy. Patient outcome was determined using the Glasgow Outcome Scale at discharge and at a mean of 12 months post operation (range 6-25 months).
Two cervical carotid aneurysms (6%) were resected followed by primary reanastomosis, 21 aneurysms (66%) were trapped following saphenous vein high-flow bypasses, five (16%) were clipped after superficial temporal or occipital artery low-flow bypasses, and four (12%) middle cerebral branch arteries were reimplanted. Of the 32 patients at discharge, 29 (91%) had a Glasgow Outcome Scale of four or five, two (6%) had severe disability, and one (3%) died.
Cerebral revascularization remains an effective and reliable procedure for treatment of complex cerebral aneurysms. Low morbidity and mortality rates reflect the maturity of patient selection and surgical technique in the management of these lesions.
The treatment of unruptured, intracranial aneurysms has been the topic of debate. Although recent studies have advocated surgical intervention for unruptured aneurysms, the risk of such treatment in comparison to outcome from ruptured aneurysms has not been established.
This retrospective study examines the outcome of 134 patients with 179 ruptured and unruptured intracranial, saccular aneurysms treated by a single surgeon.
Of the 98 ruptured aneurysms where early surgical intervention was undertaken (less than 48 hours post hemorrhage), 70 had an excellent outcome, 13 were good, four were moderate, two poor and nine patients died postoperatively. Outcome assessment in these cases was correlated to preoperative neurological status. Patients who presented with unruptured aneurysms fell into two categories: symptomatic and asymptomatic. Seven incidental, asymptomatic aneurysms were clipped concurrently to the surgical isolation of the culprit lesion following subarachnoid hemorrhage without influencing outcome, whilst, for varying reasons, eight unruptured aneurysms were not operated upon. Of the remaining 66 surgically treated, unruptured aneurysms, 64 had an excellent postoperative result, one was good (persisting right incomplete third nerve palsy) and one was moderate (left hemiparesis). Thirteen of these aneurysms were symptomatic, whilst 21 were asymptomatic, multiple aneurysms requiring secondary elective repair and 32 were true incidental aneurysms.
Unruptured aneurysms less than 25 mm in size may be safely, surgically treated relative to the expected natural history and, certainly, with less risk than operative intervention upon ruptured cerebral aneurysms.
Background: Brain tumors comprise more than 20% of all childhood malignancies, and constitute the greatest number of solid pediatric cancers. Incidence rates reported have varied from 2.4 to 3.5/100, 000 children, reflecting the impact of modern imaging techniques, the application of diverse investigative methodologies, and the accessibility of the community to health care. Methods: Material from patients < 18 years of age was collated from the Manitoba Cancer Foundation Tumor Registry, the personal records of Winnipeg pediatric neurologists, and autopsy data. Patient data were also obtained from hospital charts and operating room log books. Histological sections were examined and classified according to the American Cancer Society by a single neuropathologist. The chi-square test was used for statistical evaluation. Results: During the seven-year study period, the diagnosis of brain tumor was made in 89 pediatric patients, of which 88 were diagnosed premortem. The overall average annual incidence rate for both sexes was 4.03/100, 000 child-years, higher than that previously reported. The male and female average annual incidence rates were 4.2 and 3.7/100, 000 child-years, respectively. Tumor type and location were relatively unremarkable, with an expected peak of medulloblastoma occurring in young males. The yearly incidence of tumor occurrence was fairly stable, and the geographic distribution of cases within Manitoba, homogeneous. Conclusion: The highest incidence rates of pediatric brain tumors have been recorded in countries possessing sophisticated universal health care systems, possibly reflecting their efficacy in disease surveillance.
The incidence of vestibular schwannoma (acoustic neuroma) in Manitoba, Canada was reviewed. From 1987 through 1991, 71 tumors were diagnosed in 69 patients. The overall annual incidence rate for both sexes was 1.27/100,000 with male and female annual incidences of 1.31/100,000 and 1.24/100,000 respectively. For males, there was an early peak in the age group 30 - 39 years (2.1/100,000). Following the fifth decade, the incidence for males plateaued (2.7 - 3.6/100,000). For females, the incidence increased with age up to age 60 - 69 years (4.1/100,000). This was followed by a progressive decline in the incidence. Although the incidence of vestibular schwannoma was relatively high, the clinical features were not unlike those previously reported in the literature.
The motivation of this study was to more precisely define the in vivo role of astrocytes in forebrain ischemia. Controversy exists in the literature as to whether they protect or injure neurons in this setting.
Astrocytes in the rat hippocampus were disabled with stereotactic administration of a gliotoxin, ethidium bromide, 3 days prior to induction of forebrain ischemia. The extent of neuronal injury in this group was compared to a control category receiving intrahippocampal saline only.
Saline-injected animals demonstrated decreased hippocampal CA1 sector injury, and increased gliosis on the side of the injection compared to the contralateral side (P < 0.01) or ethidium bromide-treated animals (P < 0.05).
The results suggest that activated astrocytes are protective to neurons subjected to an ischemic insult. This may result from their ability to elaborate neurotrophic factors, buffer potassium and metabolize a variety of neurotransmitters.
Transient forebrain ischemia was induced in rats whose brain temperature was 31, 33, 35, 38, or 40°C. The development of regional injury was followed using magnetic resonance (MR) imaging, with the ultimate extent of neuronal injury quantified histopathologically. Animals in the hypothermic groups showed minimal changes in MR images over 4 days; normothermic animals snowed intensity enhancement attributed to progressive edema developing in the striatum and, later, in the hippocampus. Ischemia at 40°C resulted in widespread edema formation by I day post-ischemia; animals in this group did not survive beyond 30 hours. Histopathological analysis at 4 days (1 day for the hyperthermic group) post-ischemia showed that neuronal damage in the normothermic group was confined to the hippocampus and striatum. Minimal damage was found in the hypothermic groups; damage in the hyperthermic group was severe throughout the forebrain. There were no differences in the pre-ischemia 31P MR spectra for the different groups. During ischemia, the increase in intensity of the Pi peak and the fall in tissue pH increased with temperature in the order hypothermic < normothermic < hyperthermic group of animals. Post-ischemia energy recovery was similar in all groups, while pH recovered more rapidly in hypothermic animals.
Proton nuclear magnetic resonance (NMR) spectroscopy was used to examine cerebrospinal fluid (CSF) from patients (n = 30) with actively progressive multiple sclerosis (MS). Metabolite concentrations obtained from the spectra were compared to those determined from the spectra of CSF from control patients (n = 27) with benign spinal disorders. No significant difference was found between the 2 groups for most constituents, including lactate, glutamine, citrate, creatine and creatinine, and glucose. Acetate levels were significantly higher in MS patients, while formate levels were significantly lower, than the controls. There were no significant differences in metabolite concentrations in CSF from early and longstanding MS patients. A peak due to an unidentified compound was found at 2.82 ppm in the spectra of CSF from patients with actively progressive MS, but not in the spectra of CSF from the controls. The peak was not found in spectra of CSF from patients with AIDS dementia complex (n = 9) or Parkinson's disease (n = 5), but it did appear in spectra of CSF from 1 patient with Jakob-Creutzfeldt disease (out of 3 examined) and from 1 patient (out of 7) with Guillan-Barré disease. The unidentified compound is volatile and, from the chemical shift of the observed NMR peak, is probably an N-methyl compound. As such, it may be an intermediate in the cholino-glycine cycle, in which an abnormality has been proposed to exist in MS patients.
Hyperacute surgical evacuation of intracerebral hemorrhage is associated with a high rebleeding rate. The peri-operative administration of rFVIIa to patients with intracerebral hemorrhage may decrease the frequency of post-operative hemorrhage, and improve outcome.
Patients receiving recombinant activated factor VII (rFVIIA) therapy immediately prior to acute surgery were collected at two centres. The intracerebral hemorrhage (ICH) score and ICH Grading Scale were determined, as was long-term outcome using the modified Rankin Scale. Residual/ recurrent clot was evaluated by comparing pre-operative to post-operative CT scans.
Fifteen patients with intracerebral hemorrhage received 40-90 μg/kg of rFVIIa and underwent surgical hematoma evacuation at a median time of five hours following symptom onset. Median pre-operative clot volume was 60 ml, decreasing to 2 ml post-operatively. There were no thromboembolic adverse events. Thirteen patients survived, 11 (73%) were independent, and two (13%) had a moderate to severe disability. These outcomes were significantly better than expected based on the median ICH score (40% mortality) and based on median ICH Grading Scale (18% good outcome).
The pre or peri-operative administration of rFVIIa resulted in minimal residual or recurrent hematoma volume and may be an important adjunct to surgery in patients with intracerebral hemorrhage.
A meta-analysis of randomized controlled trials (RCTs) was conducted to update the available evidence on the safety and efficacy of carotid endarterectomy (CEA) versus carotid artery stenting (CAS) in the treatment of carotid artery stenosis.
A comprehensive search was performed of MEDLINE, EMBASE, CENTRAL, bibliographies of included articles and past systematic reviews, and abstract lists of recent scientific conferences. For each reported outcome, a Mantel-Haenszel random-effects model was used to calculate odds ratios (ORs) and 95% confidence intervals (CI). The I2 statistic was used as a measure of heterogeneity.
Twelve RCTs enrolling 6,973 patients were included in the meta-analysis. Carotid artery stenting was associated with a significantly greater odds of periprocedural stroke (OR 1.72, 95% CI 1.20 to 2.47) and a significantly lower odds of periprocedural myocardial infarction (OR 0.47, 95% CI 0.29 to 0.78) and cranial neuropathy (OR 0.08, 95% CI, 0.04 to 0.16). The odds of periprocedural death (OR 1.11, 95% CI 0.56 to 2.18), target vessel restenosis (OR 1.95, 95% CI 0.63 to 6.06), and access-related hematoma were similar following either intervention (OR 0.60, 95% CI 0.30 to 1.21).
In comparison with CEA, CAS is associated with a greater odds of stroke and a lower odds of myocardial infarction. While the results our meta-analysis support the continued use of CEA as the standard of care in the treatment of carotid artery stenosis, CAS is a viable alternative in patients at elevated risk of cardiac complications.
Severe traumatic brain injury (sTBI) is a relatively common problem with few therapies proven effective. Despite its use for over 50 years, therapeutic hypothermia has not gained widespread acceptance in the treatment of sTBI due to conflicting results from clinical trials. This review will summarize the current evidence from animal, mechanistic and clinical studies supporting the use of therapeutic hypothermia. In addition, issues of rewarming and optimal temperature will be discussed. Finally, the future of hypothermia in sTBI will be addressed.
This study demonstrates the utility of a newly-developed moveable 1.5 Tesla intraoperative MR imaging system using a case report of a multi-lobulated parafalx meningioma.
A 43-year-old female presented with progression of a multi-lobulated anterior parafalx meningioma several years following resection of a large left frontal convexity meningioma.
Intervention and Technique:
Surgical excision of the lesion was undertaken. Following apparent total resection, intraoperative MR imaging revealed two residual dumbell shaped lobules. Using these updated MR images, the tumour was readily identified and removed.
The moveable 1.5 Tesla intraoperative MR system used in the present case provides rapid, high resolution MR images during neurosurgical procedures. Moving the magnet out of the surgical field during surgery permits the use of all standard neurosurgical instruments. The ease of use and quality of images combined with minimal interference on well-established surgical techniques makes this system a valuable adjunct in the neurosurgical treatment of intracranial disease.
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