Citations

Background and Purpose— Emerging evidence demonstrating the high sensitivity of early brain computed tomography (CT) brings into question the necessity of always performing lumbar puncture after a negative CT in the diagnosis of spontaneous subarachnoid hemorrhage (SAH). Our objective was to determine the sensitivity of brain CT using modern scanners (16-slice technology or greater) when performed within 6 hours of headache onset to exclude SAH in neurologically intact patients. Methods— After conducting a comprehensive literature search using Ovid MEDLINE, Ovid EMBASE, Web of Science, and Scopus, we conducted a meta-analysis. We included original research studies of adults presenting with a history concerning for spontaneous SAH and who had noncontrast brain CT scan using a modern generation multidetector CT scanner within 6 hours of symptom onset. Our study adheres to the preferred reporting items for systematic reviews and meta-analyses (PRISMA). Results— A total of 882 titles were reviewed and 5 articles met inclusion criteria, including an estimated 8907 patients. Thirteen had a missed SAH (incidence 1.46 per 1000) on brain CTs within 6 hours. Overall sensitivity of the CT was 0.987 (95% confidence intervals, 0.971–0.994) and specificity was 0.999 (95% confidence intervals, 0.993–1.0). The pooled likelihood ratio of a negative CT was 0.010 (95% confidence intervals, 0.003–0.034). Conclusions— In patients presenting with thunderclap headache and normal neurological examination, normal brain CT within 6 hours of headache is extremely sensitive in ruling out aneurysmal SAH.

AbstractIntroductionThe objective of our study was to investigate cross‐sectional associations of atrial fibrillation with neuroimaging measures of cerebrovascular disease and Alzheimer's disease and their interactions with mild cognitive impairment (MCI).MethodsMagnetic resonance imaging scans of individuals from a population‐based study were analyzed for infarctions, total gray matter, and hippocampal and white matter hyperintensity volumes. A subsample underwent positron emission tomography imaging.ResultsAtrial fibrillation was associated with infarctions and lower total gray matter volume. Compared with subjects with no atrial fibrillation and no infarction, the odds ratio (95% confidence intervals) for MCI was 2.99 (1.57–5.70; P = .001) among participants with atrial fibrillation and infarction, 0.90 (0.45–1.80; P = .77) for atrial fibrillation and no infarction, and 1.50 (0.96–2.34; P = .08) for no atrial fibrillation and any infarction.DiscussionParticipants with both atrial fibrillation and infarction are more likely to have MCI than participants with either infarction or atrial fibrillation alone.

Objective In certain situations, severe forms of Guillain-Barré syndrome (GBS) show no response or continue to deteriorate after intravenous immunoglobulin (IVIg) infusion. It is unclear what the best treatment option would be in these circumstances.Method This is a case report on patients with severe axonal GBS in whom a second cycle of IVIg was used.Results Three patients on mechanical ventilation who presented axonal variants of GBS, with autonomic dysfunction, bulbar impairment and Erasmus score > 6, showed no improvement after IVIg infusion of 400 mg/kg/d for 5 days. After 6 weeks, we started a second cycle of IVIg using the same doses and regimen as in the previous one. On average, 5 days after the second infusion, all the patients were weaned off mechanical ventilation and showed resolution of their blood pressure and heart rate fluctuations.Conclusions A second cycle of IVIg may be an option for treating severe forms of GBS.

Background and purpose Many studies have suggested a relationship between the type of anesthesia provided during intra-arterial therapy for acute ischemic stroke and patient outcomes. Variability in blood pressure and hypotension have previously been identified as possible reasons for worse outcomes in acute stroke. Our aim was to investigate hemodynamic parameters and neurological outcomes of patients receiving either general anesthesia or conscious sedation for intra-arterial therapy of acute stroke. Methods We performed a retrospective review of patients undergoing intra-arterial therapy from December 2008 to March 2015. Demographic data, baseline National Institutes of Health Stroke Scale score, preoperative physiological variables, procedural details, systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), heart rate, and modified Rankin Scale scores were recorded. Results 99 patients were included in the study, with 38 receiving general anesthesia and 61 receiving conscious sedation. Patients who received general anesthesia had a lower maximum SBP (p=0.02), minimum SBP (p<0.0001), minimum DBP (p<0.0001), and minimum MAP (p<0.0001). On multivariate analysis, general anesthesia was associated with lower minimum SBP (p=0.04), DBP (p=0.02), and MAP (p=0.007). Conscious sedation was associated with more favorable neurological outcomes (p=0.02). Patients with favorable neurological outcomes had a lower maximum variability in SBP (p=0.01) and MAP (p=0.03), as well as a higher minimum DBP (p=0.03). Conclusions Patients with acute ischemic stroke undergoing intra-arterial therapy with general anesthesia had lower minimum SBP, DBP, and MAP, greater fluctuations in blood pressure, and less favorable outcomes. More studies are needed to examine the implications of variable and reduced blood pressures and neurological outcomes.

Carotid artery stenosis is a well-established risk factor of ischemic stroke, contributing to up to 10%-20% of strokes or transient ischemic attacks. Many clinical trials over the last 20 years have used measurements of carotid artery stenosis as a means to risk stratify patients. However, with improvements in vascular imaging techniques such as CT angiography and MR angiography, ultrasonography, and PET/CT, it is now possible to risk stratify patients, not just on the degree of carotid artery stenosis but also on how vulnerable the plaque is to rupture, resulting in ischemic stroke. These imaging techniques are ushering in an emerging paradigm shift that allows for risk stratifications based on the presence of imaging features such as intraplaque hemorrhage (IPH), plaque ulceration, plaque neovascularity, fibrous cap thickness, and presence of a lipid-rich necrotic core (LRNC). It is important for the neurosurgeon to be aware of these new imaging techniques that allow for improved patient risk stratification and outcomes. For example, a patient with a low-grade stenosis but an ulcerated plaque may benefit more from a revascularization procedure than a patient with a stable 70% asymptomatic stenosis with a thick fibrous cap. This review summarizes the current state-of-the-art advances in carotid plaque imaging. Currently, MRI is the gold standard in carotid plaque imaging, with its high resolution and high sensitivity for identifying IPH, ulceration, LRNC, and inflammation. However, MRI is limited due to time constraints. CT also allows for high-resolution imaging and can accurately detect ulceration and calcification, but cannot reliably differentiate LRNC from IPH. PET/CT is an effective technique to identify active inflammation within the plaque, but it does not allow for assessment of anatomy, ulceration, IPH, or LRNC. Ultrasonography, with the aid of contrast enhancement, is a cost-effective technique to assess plaque morphology and characteristics, but it is limited in sensitivity and specificity for detecting LRNC, plaque hemorrhage, and ulceration compared with MRI. Also summarized is how these advanced imaging techniques are being used in clinical practice to risk stratify patients with low- and high-grade carotid artery stenosis. For example, identification of IPH on MRI in patients with low-grade carotid artery stenosis is a risk factor for failure of medical therapy, and studies have shown that such patients may fair better with carotid endarterectomy (CEA). MR plaque imaging has also been found to be useful in identifying revascularization candidates who would be better candidates for CEA than carotid artery stenting (CAS), as high intraplaque signal on time of flight imaging is associated with vulnerable plaque and increased rates of adverse events in patients undergoing CAS but not CEA.

OBJECT External ventricular drainage (EVD) after intraventricular hemorrhage (IVH) without symptomatic hydrocephalus is controversial. The object of this study was to examine indicators or the timeframe for hydrocephalus in patients not immediately treated with EVD after IVH. METHODS Records from 2007 to 2014 were searched for “intraventricular hemorrhage” or “IVH.” Inclusion criteria were IVH after intracerebral hemorrhage (ICH), trauma, tumor, or vascular anomalies. Exclusion criteria were IVH with more than minimal subarachnoid hemorrhage, catastrophic ICH, layering IVH only, or hydrocephalus treated immediately with EVD. IVH was measured with the modified Graeb Score (mGS). An mGS of 5 indicates a full ventricle with dilation. Statistics included chi-square, Student’s t-test, and Mann-Whitney tests; receiver operating characteristics; and uni- and multivariate logistic regression. RESULTS One hundred five patients met the criteria; of these, 30 (28.6%) required EVD. Panventricular IVH was the most common pattern (n = 49, 46.7%), with 25 of these patients (51%) requiring EVD. The median mGS was 18 ± 5.4 (range 12–29) and 9 ± 4.5 (range 2–21) in the EVD and No-EVD groups, respectively (p < 0.001). Factors associated with EVD were radiological hydrocephalus at presentation, midline shift > 5 mm, Glasgow Coma Scale (GCS) score < 8, mGS > 13, third ventricle mGS = 5, and fourth ventricle mGS = 5. On multivariate analysis, GCS score < 8 [4.02 (range 1.13–14.84), p = 0.032], mGS > 13 [3.83 (range 1.02–14.89), p = 0.046], and fourth ventricle mGS = 5 [5.01 (range 1.26–22.78), p = 0.022] remained significant. Most patients treated with EVD (n = 25, 83.3%) required it soon after presentation [6.4 ± 3.3 (range 1.5–14) hrs]. The remaining 5 patients (16.7%) had a delayed EVD requirement [70.7 ± 22.7 (range 50–104.5) hrs]. CONCLUSIONS In this study population, the risk for EVD was variable, but greater with mGS > 13, coma, and a dilated fourth ventricle. While the need for EVD occurs within the 1st day after IVH in most patients, a minority require EVD after 48 hours.

OBJECT This study was undertaken to analyze the predisposing factors, clinical presentation, therapeutic management, and clinical recovery in patients with pituitary apoplexy, with an emphasis on the long-term visual, endocrine, and functional outcomes. METHODS The authors performed a retrospective analysis of consecutive cases involving patients treated at Mayo Clinic between 1992 and 2013. Patients were included in the study only if they had 1) abrupt onset of severe headache or visual disturbance in the presence of a pituitary adenoma and 2) radiological or surgical confirmation of a pituitary mass. The primary endpoints of analysis were the visual (ocular motility, visual fields, and visual acuity), endocrine, and functional outcomes (using the modified Rankin Scale). RESULTS Eighty-seven patients were identified (57 males and 30 females, mean age 50.9 years, range 15–91 years). Twenty-two patients (25.3%) had a known pituitary adenoma. Hypertension was the most common associated factor (39%). Headache was the most frequent presenting symptom (89.7%), followed by visual abnormalities (47.1%). Cranial nerve palsies were present in 39% and visual field defects in 34.1%. MRI detected hemorrhage in 89% patients, as compared with 42% detected by CT scan. Sixty-one patients (70.1%) underwent surgery during acute hospitalization (median time from apoplexy 5 days, IQR 3–10 days), 8 (9.2%) had delayed surgery, and 18 (20.7%) were treated conservatively. Histopathological examination revealed adenoma with pure necrosis in 18 (30%), pure hemorrhage in 4 (6.7%), and both in 6 (10%) patients. Four patients died during hospitalization. The average duration of follow-up was 44.2 ± 43.8 months. All survivors were independent and had complete resolution or substantial improvement in eye movements and visual fields at the last follow-up. Many patients needed long-term hormonal replacement with levothyroxine (62.7%) and cortisol (60%). Daily desmopressin was needed in 23% of all surgical patients at 3 months (versus none of the medically treated) and this requirement decreased slightly over time. Regrowth of pituitary adenoma was seen in 7 patients (8.6%). There were no statistically significant differences in any of the outcome measures across the treatment groups. CONCLUSIONS The outcome of most patients with pituitary apoplexy is excellent. Selected patients can be managed conservatively, and patients with severe neuro-ophthalmological deficits treated with early surgery can achieve an excellent recovery.

Most of the contraindications to the administration of intravenous (IV) recombinant tissue plasminogen activator (rtPA) originated as exclusion criteria in major stroke trials. These were derived from expert consensus for the National Institute of Neurological Disorders and Stroke (NINDS) trial. Despite the fact that the safety and efficacy of IV rtPA has been repeatedly confirmed in large international observational studies over the past 20 years, most patients with acute ischemic stroke disappointingly still do not receive thrombolytic treatment. Some of the original exclusion criteria have proven to be unnecessarily restrictive in real-world clinical practice. It has been suggested that application of relaxed exclusion criteria might increase the IV thrombolysis rate up to 20% with comparable outcomes to thrombolysis with more conventional criteria. We review the absolute and relative contraindications to IV rtPA for acute ischemic stroke, discussing the underlying rationale and evidence supporting these exclusion criteria.