Such As Subarachnoid Hemorrhage Research Articles

StrokeNet: An automated approach for segmentation and rupture risk prediction of intracranial aneurysm.

Intracranial Aneurysms (IA) present a complex challenge for neurosurgeons as the risks associated with surgical intervention, such as Subarachnoid Hemorrhage (SAH) mortality and morbidity, may outweigh the benefits of aneurysmal occlusion in some cases. Hence, there is a critical need for developing techniques that assist physicians in assessing the risk of aneurysm rupture to determine which aneurysms require treatment. However, a reliable IA rupture risk prediction technique is currently unavailable. To address this issue, this study proposes a novel approach for aneurysm segmentation and multidisciplinary rupture prediction using 2D Digital Subtraction Angiography (DSA) images. The proposed method involves training a fully connected convolutional neural network (CNN) to segment aneurysm regions in DSA images, followed by extracting and fusing different features using a multidisciplinary approach, including deep features, geometrical features, Fourier descriptor, and shear pressure on the aneurysm wall. The proposed method also adopts a fast correlation-based filter approach to drop highly correlated features from the set of fused features. Finally, the selected fused features are passed through a Decision Tree classifier to predict the rupture severity of the associated aneurysm into four classes: Mild, Moderate, Severe, and Critical. The proposed method is evaluated on a newly developed DSA image dataset and on public datasets to assess its generalizability. The system's performance is also evaluated on DSA images annotated by expert neurosurgeons for the rupture risk assessment of the segmented aneurysm. The proposed system outperforms existing state-of-the-art segmentation methods, achieving an 85 % accuracy against annotated DSA images for the risk assessment of aneurysmal rupture.

PP296 Patient Involvement In An Assessment Of The Management Of Sudden Onset Severe Headache Presenting To The Emergency Department

IntroductionSudden onset severe headache is usually caused by a primary headache disorder but may be secondary to a more serious problem, such as subarachnoid hemorrhage (SAH). Very few patients who present to hospital with headache have suffered a SAH, but early identification is important to improve patient outcomes. A systematic review was undertaken to assess the clinical effectiveness of different care pathways for the management of headache, suspicious for SAH, in the Emergency Department. Capturing the perspective of patients was an important part of the research.MethodsThe project team included a patient collaborator with experience of presenting to the Emergency Department with sudden onset severe headache. Three additional patients were recruited to our advisory group. The patient's perspective was collected at various points through the project including at team meetings, during protocol development and when interpreting the results of the systematic review and drawing conclusions.ResultsPatients were reassured by the very high diagnostic accuracy of computed tomography (CT) for detecting SAH. Patients and clinicians emphasized the importance of shared decision making about whether to undergo additional tests to rule out SAH, after a negative CT result. When lumbar puncture was necessary, patients expressed a preference to have it on an ambulatory basis; further research on the safety and acceptability of ambulatory lumbar puncture was recommended.ConclusionsPatient input at the protocol development stage helped researchers understand the patient experience and highlighted important outcomes for assessment. Patient involvement added context to the review findings and highlighted the preferences of patients regarding the management of headache.

PP297 Management Of Sudden Onset Severe Headache Presenting To The Emergency Department: A Systematic Review

IntroductionSudden onset severe headache is usually caused by a primary headache disorder but occasionally is secondary to a more serious problem, such as subarachnoid hemorrhage (SAH). Guidelines recommend non-contrast brain computed tomography (CT) followed by lumbar puncture (LP) to exclude SAH. However, guidelines pre-date the introduction of more sensitive modern CT scanners. A systematic review was undertaken to assess the clinical effectiveness of different care pathways for the management of headache in the Emergency Department.MethodsEighteen databases (including MEDLINE and Embase) were searched to February 2020. Studies were quality assessed using criteria relevant to the study design; most studies were assessed using the QUADAS-2 tool for diagnostic accuracy studies. Where sufficient information was reported, diagnostic accuracy data were extracted into 2 × 2 tables to calculate sensitivity, specificity, false-positive and false-negative rates. Where possible, hierarchical bivariate meta-analysis was used to synthesize results, otherwise studies were synthesized narratively.ResultsFifty-one studies were included in the review. Eight studies assessing the accuracy of the Ottawa SAH clinical decision rule were pooled; sensitivity was 99.5 percent, specificity was 23.7 percent. The high false positive rate suggests that 76.3 percent SAH-negative patients would undergo further investigation unnecessarily. Four studies assessing the accuracy of CT within six hours of headache onset were pooled; sensitivity was 98.7 percent, specificity was 100 percent. CT sensitivity beyond six hours was considerably lower (≤90%; 2 studies). Three studies assessing LP following negative CT were pooled; sensitivity was 100 percent, specificity was 95.2 percent. LP-related adverse events were reported in 5.3–9.5 percent of patients.ConclusionsThe evidence suggests that the Ottawa SAH Rule is not sufficiently accurate for ruling out SAH and does little to aid clinical decision making. Modern CT within six hours of headache onset (with images assessed by a neuroradiologist) is highly accurate, but sensitivity reduces considerably over time. The CT-LP pathway is highly sensitive for detecting SAH, although LP resulted in some false-positives and adverse events.

Shallow 3D CNN for Detecting Acute Brain Hemorrhage From Medical Imaging Sensors

Successive layers in convolutional neural networks (CNN) extract different features from input images. Applications of CNNs to detect abnormalities in the 2D images or 3D volumes of body organs have recently become popular. However, computer-aided detection of diseases using deep CNN is challenging due to the absence of a large set of training medical images/scans and the relatively small and hard to detect abnormalities. In this paper, we propose a method for normalizing 3D volumetric scans using the intensity profile of the training samples. This aids the CNN by creating a higher contrast around the abnormal region of interest in the scan. We use the CQ500 head CT dataset to demonstrate the validity of our method for detecting different acute brain hemorrhages such as subarachnoid hemorrhage (SAH), intraparenchymal hemorrhage (IPH), subdural hematoma (SDH), and intraventricular hemorrhage (IVH). We compare the proposed method with a baseline, two variants of the 3D VGGNet architectures, Resnet, and show that the proposed method achieves significant improvement in classification performance. For binary classification, we achieved the best F1 score of 0.96 (normal vs SAH), 0.93 (normal vs IPH), 0.98 (normal vs SDH), and 0.99 (normal vs IVH), and for four-class classification, we obtained an average F1 score of 0.77. Finally, we show a limitation of the proposed method while detecting varied abnormalities. The proposed method has applications for abnormality detection for different organs.

Racial and Ethnic Disparities in Mortality in US Veterans Following an Incident Subarachnoid Hemorrhage

Background Blacks and Hispanics have been shown to have higher stroke mortality than Whites. However, few studies have investigated health disparities in post-stroke mortality for specific stroke types, such as subarachnoid hemorrhage (SAH). We analyzed risk of mortality by race/ethnicity after incident SAH in a national sample of stroke patients from the Veteran's Health Administration (VHA). Methods We included 742 patients (98% male, mean age 63±13 years) with a first occurrence of an inpatient SAH in a VHA hospital between 2002-2007. SAH was determined by ICD-9 code 430. We categorized patients as non-Hispanic White, non-Hispanic Black, or Hispanic. Veterans with a prior definite stroke type (including TIA) were excluded. We constructed a piecewise multivariate survival model for post event all-cause mortality, separated according to 1 year post admission follow-up intervals. We then looked at 30-day mortality for vascular and stroke specific deaths. Results The proportion of White, Black, and Hispanic patients was 66%, 23%, and 11% respectively. Total mortality at 30 days, 90 days, 1 year, and end of follow up was 22%, 27%, 33% and 54% respectively. Compared to Whites, Hispanics had higher mortality in the first 30 days post stroke (HR=1.67 95% CI=1.08-2.30), while Blacks and Whites experienced similar mortality (HR=1.02 95% CI=0.68, 1.54). Both Blacks and Hispanics had worse vascular (Black vs White HR=1.59 95% CI=0.95-2.66; Hispanic vs White HR=2.04 95% CI=1.13-3.66) and stroke-specific (Black vs White HR=1.47 95% CI=0.81-2.67; Hispanic vs White HR=2.12 95% CI=1.16-4.22) mortality (“case-fatality”) than Whites in the first 30 days. Conclusion Survivorship following subarachnoid hemorrhage varies in Veterans according to race and ethnicity. Further research into the severity of the stroke as well as risk factor control before and after stroke could help to improve our understanding of these differences.

Obesity paradox in subarachnoid hemorrhage: a systematic review

As the number of obese people is globally increasing, reports about the putative protective effect of obesity in life-threatening diseases, such as subarachnoid hemorrhage (SAH), are gaining more interest. This theory—the obesity paradox—is challenging to study, and the impact of obesity has remained unclear in survival of several critical illnesses, including SAH. Thus, we performed a systematic review to clarify the relation of obesity and SAH mortality. Our study protocol included systematic literature search in PubMed, Scopus, and Cochrane library databases, whereas risk-of-bias estimation and quality of each selected study were evaluated by the Critical Appraisal Skills Program and Cochrane Collaboration guidelines. A directional power analysis was performed to estimate sufficient sample size for significant results. From 176 reviewed studies, six fulfilled our eligibility criteria for qualitative analysis. One study found paradoxical effect (odds ratio, OR = 0.83 (0.74–0.92)) between morbid obesity (body mass index (BMI) > 40) and in-hospital SAH mortality, and another study found the effect between continuously increasing BMI and both short-term (OR = 0.90 (0.82–0.99)) and long-term SAH mortalities (OR = 0.92 (0.85–0.98)). However, according to our quality assessment, methodological shortcomings expose all reviewed studies to a high-risk-of-bias. Even though two studies suggest that obesity may protect SAH patients from death in the acute phase, all reviewed studies suffered from methodological shortcomings that have been typical in the research field of obesity paradox. Therefore, no definite conclusions could be drawn.

Middle cerebral artery dissection causing subarachnoid hemorrhage and cerebral infarction: Trapping with high-flow bypass preserving the lenticulostriate artery

Background:Spontaneous intracranial arterial dissection (IAD) is an increasingly important cause of stroke, such as subarachnoid hemorrhage (SAH) and hemodynamic or thromboembolic cerebral ischemia. IAD usually occurs in the posterior circulation, and is relatively rare in the anterior circulation including the middle cerebral artery (MCA). Various surgical and endovascular methods to reduce blood flow in the dissected lesion have been proposed, but no optimum treatment has been established.Case Description:An 80-year-old woman with dissection in the M1 portion of the MCA manifesting as SAH presented with repeated hemorrhage and cerebral infarction in the area of the inferior trunk of the MCA. High-flow bypass to the MCA was performed and the dissecting lesion was trapped. Prevention of repeated hemorrhage was achieved, and blood flow was preserved to the lenticulostriate artery as well as the MCA area distal to the lesion.Conclusions:Treatment strategy for IAD of the MCA should be planned for each patient and condition, and surgery should be performed promptly to prevent critical rebleeding given the high recurrence rate. In addition, preventing re-rupture of the IAD, and preserving important perforators around the lesion and blood flow distal to the dissection should be targeted by the treatment strategy.

Regional cerebral blood flow and cellular environment in subarachnoid hemorrhage: A thermal doppler flowmetry and microdialysis study

BackgroundCerebral microdialysis enables assessment of regional metabolic physiology and provides biomarkers for clinical correlation in critical conditions, such as subarachnoid hemorrhage (SAH). The aim of our current study was to investigate the correlation between regional cerebral blood flow and microdialysis parameters (glucose, lactate, glycerol, pyruvate concentrations, and lactate/pyruvate metabolic ratio) in patients with SAH. Materials and methodsTwenty-one patients with SAH were enrolled in our retrospective study. Cerebral blood flow (CBF) based on thermal diffusion methodology, the thermal coefficient K, and microdialysis biochemical markers were recorded. The duration of the brain monitoring was 10 days. ResultsMicrodialysis glucose concentration was inversely related to the cerebral temperature and to the L/P ratio. Furthermore, it was positively correlated to all other microdialysis parameters but glycerol. The K coefficient was strongly and positively correlated with the temperature and marginally with the CBF. The L/P ratio was positively correlated with glycerol, while it was inversely correlated with the CBF. Patients who died had elevated L/P ratio and K coefficient compared to the survivors in our series. ConclusionsThermal conductivity coefficient may change over time as cerebral injury progresses and tissue properties alter. These alterations were found to be associated with the microdialysis metabolite concentrations and the CBF itself. The microdialysis biochemical indices of cell stress and death (glycerol, L/P ratio) were positively related to each other, while the measured L/P metabolic ratio was higher among patients who died.

Intracerebroventricular application of S100B selectively impairs pial arteriolar dilating function in rats

S100B is an astrocyte-derived protein that can act through the receptor for advanced glycation endproducts (RAGE) to mediate either “trophic” or “toxic” responses. Its levels increase in many neurological conditions with associated microvascular dysregulation, such as subarachnoid hemorrhage (SAH) and traumatic brain injury. The role of S100B in the pathogenesis of microvasculopathy has not been addressed. This study was designed to examine whether S100B alters pial arteriolar vasodilating function. Rats were randomized to receive (1) artificial cerebrospinal fluid (aCSF), (2) exogenous S100B, and (3) exogenous S100B+the decoy soluble RAGE (sRAGE). S100B was infused intracerebroventricularly (icv) using an osmotic pump and its levels in the CSF were adjusted to achieve a concentration similar to what we observed in SAH. After 48h of continuous icv infusion, a cranial window/intravital microscopy was applied to animals for evaluation of pial arteriolar dilating responses to sciatic nerve stimulation (SNS), hypercapnia, and topical suffusion of vasodilators including acetylcholine (ACh), s-nitroso-N-acetyl penicillamine (SNAP), or adenosine (ADO). Pial arteriolar dilating responses were calculated as the percentage change of arteriolar diameter in relation to baseline. The continuous S100B infusion for 48h was associated with reduced responses to the neuronal-dependent vasodilator SNS (p<0.05) and the endothelial-dependent vasodilator ACh (p<0.05), compared to controls. The inhibitory effects of S100B were prevented by sRAGE. On the other hand, S100B did not alter the responses elicited by vascular smooth muscle cell-dependent vasodilators, namely hypercapnia, SNAP, or ADO. These findings indicate that S100B regulates neuronal and endothelial dependent cerebral arteriolar dilation and suggest that this phenomenon is mediated through RAGE-associated pathways.

Secondary headache in emergency.

Headache is one of the most common causes of access to Emergency Departments (ED). Primary headaches and headaches secondary to benign conditions (e.g headache attributed to acute sinusitis) represent the majority of cases, while secondary life-threatening headaches are less frequent. The primary objective in the ED setting is to decide whether the headache is primary or secondary and recognize serious life-threatening conditions presenting with headache and requiring prompt medical diagnosis and care, such as subarachnoid hemorrhage (SAH), intracerebral hemorrhage, cerebral venous sinus thrombosis (CVST), cervical artery dissection (CAD), brain tumors, pituitary apoplexy, spontaneous intracranial hypotension, or intracranial infections. Careful history taking and physical examination remain the most important part of the assessment of the headache patient[1]. A thorough history should investigate the onset of headache, quality, location and irradiation of pain, associated symptoms experienced before and during the headache, concomitant medical conditions, medication use, recent trauma or interventions. The examination should then target areas identified as abnormal during the headache history; funduscopy evaluation should be performed when symptoms may suggest an increased intracranial pressure; in addition, a complete neurological assessment including level of consciousness, cranial nerve testing, pupillary responses, motor strength and sensorial testing, and signs of meningeal irritation is essential[2]. Based on historical and physical findings “red flags” for secondary headache disorders are sudden onset, onset after 50 years of age, increased frequency, severity or significant change in the usual headache pattern, new onset with an underlying medical condition (such as cancer or immunodepression), concomitant signs of systemic illness (such as fever, neck stiffness, rash), focal neurologic signs or symptoms, papilledema, and head trauma[2]. In headache patients with one or more “red flags” a diagnostic workup is indicated including blood tests, neuroimaging studies, and cerebrospinal fluid (CSF) examinations, which are selected depending on the patient's history and findings. Blood testing and dosage of inflammation indexes (erythrocyte sedimentation rate, C-reactive protein) should be performed in all headache patients especially when an infective or inflammatory condition is suspected. In the ED, non-contrast computed tomography (CT) is the preferred imaging study and is used to rule out hemorrhage, while most patients should perform a magnetic resonance imaging (MRI) brain scan followed by CT/MRI angiography if brain vessel disease is suspected (such as, CAD, aneurysms, and CVST). Lumbar puncture with CSF analysis may help to diagnose SAH, infection, tumor and disorders related to CSF hypertension or hypotension[3, 4]. Treatment and prognosis depend on the etiology of the headache. Prompt recognition and early treatment of secondary headache are essential to avoid some preventable complications.

E-058 clinical features of aneurysmal subarachnoid hemorrhage associated with takotsubo cardiomyopathy

Introduction Takotsubo cardiomyopathy (TCM) is characterized by elevation of ST segment in the electrocardiogram and left ventricular apical ballooning in the left ventriculography. Emotional or physical stress such as subarachnoid hemorrhage (SAH) triggers takotsubo cadiomyopathy. Cardiac failure and pulmonary edema often increase in severity. The strict causes of this disease are unknown. We reviewed the clinical features and outcomes of our series of this disease. [Materials and Methods]Between January 2001 and December 2014, 15 patients with SAH associated with TCM were treated at our hospital. Patients were 2 males and 13 females, mean age were 63 years old. According to the WFNS scale, grade II in 2 patients, III in 1, IV in 1, V in 11. Five patients were associated with neurogenic lung edema. [Results]Coil embolization was performed for 6 patients and surgical neck clipping for 8 patients. Five of 6 patients achieved good recovery with endovascular treatment and 3 of 8 with surgical clipping. [Conclusion] Coil embolization is the less invasive treatment option for cerebral aneurysms with TCM, even if the patient were poor condition. Early diagnosis and intensive whole body control are very important. Disclosures N. Hirotsune: None. S. Nishino: None. T. Meguro: None. K. Muraoka: None. T. Tanabe: None. Y. Okuma: None. Y. Takahashi: None. Y. Tomita: None.

Axonal Pathology in Subarachnoid and Intracerebral Hemorrhage

Electrically active axons degenerate in the presence of nitric oxide (NO) in vitro. High CSF NO concentrations have been observed in patients with hemorrhagic brain injury such as subarachnoid hemorrhage (SAH) and intracerebral hemorrhage (ICH). This study investigated the evidence for axonal injury in SAH and ICH and related this to CSF NO levels. In this study, neurofilament phosphoforms (NfH(SMI34), NfH(SMI35), NfH(SMI38), NfH(SMI310)), surrogate markers for axonal injury, and NO metabolites (nitrate, nitrite = NOx) were measured by ELISA in cerebrospinal fluid (CSF) from patients with SAH and ICH and from a group of controls. Injury severity was classified using the Glasgow Coma Scale, and survival was used as the outcome measure. Compared to the control group, a higher proportion of patients with SAH and ICH had elevated NfH(SMI34) levels from day 0 to day 6 (p < 0.001), elevated NfH(SMI35) levels from day 1 to 6 (p < 0.001), and elevated NfH(SMI310) levels at day 0, 1, 4, and 6 (p < 0.001). The NOx levels were higher in the SAH and ICH patients than in the controls (p < 0.05) and distinguished the non-survivors from the survivors (p < 0.05). No direct correlation was found for NOx with any of the NfH phosphoforms. This study provides evidence for primary and secondary axonal injury in patients with SAH and ICH, with non-survivors also having higher NOx levels. CSF NfH phosphoforms might emerge as a putative surrogate marker for monitoring the development for secondary axonal degeneration in neurocritical care and guiding targeted neuroprotective strategies.

September 23 Highlights

Frese et al. analyzed the clinical features of this headache in 51 patients. They found a male preponderance. Most patients have an explosive pain at orgasm. Attacks were not related to any particular sexual habit. There was a high comorbidity with other primary headache disorders. see page 796 Commentary by David W. Dodick, MD Headache associated with sexual activity . . . gets your attention There are few headaches that grab the attention of patients and physicians more than those associated with sexual activity. Apart from their noteworthy and peculiar intrusiveness, these headaches are most often apoplectic in onset, occur at the moment of orgasm, and as such, closely resemble the thunderclap headache sometimes associated with potentially catastrophic intracranial diseases such as subarachnoid hemorrhage (SAH). The physician’s apprehension is justifiably heightened by several facts: sudden severe headache is the most common symptom of a SAH, the sole manifestation in about 12% of cases, and precedes a catastrophic rebleed in up to 50% of patients.1,2⇓ Moreover, subarachnoid hemorrhage occurs during sexual activity in up to 11% of cases. Headache associated with sexual activity (HSA) itself often occurs repeatedly and can be quite debilitating. Therefore, any attempt to elucidate the distinguishing clinical features and underlying mechanism of this disorder is welcome. The recently revised diagnostic criteria of the International Headache Society distinguish between two types of HSA: preorgasmic (previously known as HAS type I) and orgasmic headache (previously known as HAS type II). The main distinguishing feature is the presence or absence of a headache that gradually intensifies until orgasm in preorgasmic compared to the sudden onset of a headache simultaneous with orgasm in the latter. There was insufficient evidence to provide more explicit details regarding their duration, associated symptoms, and other clinical features that may prove useful to clinicians …

Paralytic Ileus Associated with Intracranial Diseases.

Paralytic ileus is one of the most important systemic complications associated with intracranial diseases such as subarachnoid hemorrhage (SAH), intracerebral hemorrhage (ICH), cerebral infarction (CI) and cerebral contusion (CC). A patient who suffers from intracranial diseases including cerebrovascular strokes has a tendedncy to be complicated by a paralytic ileus.21)22) In this paper, we present 15 cases with intracranial diseases who suffered from paralytic ileus. Indeed, various factors such as a previous history of an abdominal operation, sepsis, trauma, and drugs may contribute to the mechanism of this complication. On the other hand, nimodipine, a kind of calcium antagonist is an effective hypotensive agent without decreasing the cerebral blood flow. But an administration of this agent sometimes causes a paralytic ileus.1)2) Nimodipine were administered for all the patients of our 15 cases with hypertension. It was suggested that an administration of nimodipine was the most significant factor of the paralytic ileus of our patients. Three patients died of paralytic ileus despite the intensive conservative treatments described as below. So we must pay attention to this unexpected complication when we use this agent for those with intracranial diseases.