Posterior circulation ischemic stroke in Korean population

Posterior Circulation Ischemic Stroke Is Associated with More Severe Forward Head Posture in Patients with Cervicalgia

BACKGROUND

Chronic risk factors of posterior circulation ischemic strokes remain unknown. There is, however, evidence that anatomical variations within the vertebrobasilar system could potentially lead to the development of posterior circulation strokes. We investigated the association of forward head posturing (FHP), a chronic anatomical change seen in patients with cervicalgia, with posterior circulation strokes.

METHODS

In this case-control study, we identified adult patients diagnosed with cervicalgia and ischemic posterior circulation infarcts from 2007 to 2023. Cases were paired with controls with cervicalgia without posterior circulation stroke and matched for known risk factors. C0-C2 angle, C2-C7 angle, and sagittal vertical axis shift were measured as metrics for FHP severity on lateral cervical spine x-rays. Paired t tests were applied to compare stroke risk factors and FHP between groups.

RESULTS

Participants included 206 patients (103 cases and 103 controls) with a mean age of 64.4 years; 51.5% were female. There were no statistically significant differences between risk factors for stroke, including hypertension, hyperlipidemia, diabetes, smoking, hypercoagulable state, and atrial fibrillation. There were statistically significant differences in C0-C2 angle (30.7° vs. 23.2°, P = 0.002) and sagittal vertical axis shift (35.4 mm vs. 25.3 mm, P < 0.001).

CONCLUSIONS

This case-control matched-pair study found that in adults with cervicalgia, posterior circulation ischemic stroke was associated with more severe FHP as noted in C0-C2 angle and sagittal vertical axis shift measurements. Further, this association may be due to chronic changes in circulation flow dynamics within the vertebrobasilar system with the postural change.

Demographic Characteristics and Functional Outcome in Posterior Circulation Strokes

INTRODUCTION

The constantly increasing incidence of stroke in Saudi Arabia substantiates an urgent need to elucidate underlying risk factors and etiologies. In terms of improving outcomes, the predictors of functional outcomes need to be identified as well. As posterior circulation strokes (PCS) have not been studied in detail, the current study aimed to identify the risk factors, etiology, and predictors of outcome in PCS.

METHODS

This retrospective study included the data for 138 patients with PCS. Demographics, risk factors, clinical signs/symptoms, etiology, and outcome at discharge and 3-month follow-up were recorded. Factors associated with outcomes were identified, and the difference was ascertained using Chi-square, odds ratios, and 95% confidence intervals.

RESULTS

The mean participant age was 58 ± 14.8 years with 73% being males. The mean arrival time was 26.5 ± 31.6 h; with a mean National Institute of Health Stroke scale (NIHSS) score of 7.2 ± 5.6. Motor deficit and dysarthria were the most common presentations. Twenty percent of patients received intravenous recombinant tissue plasminogen activator, whereas endovascular thrombectomy was performed in 9 (6.5%). Follow-up outcome at 3 months was available in 113 (81.8%). Male sex, baseline modified Rankin scale of <2, low baseline NIHSS, and stable or improvement in baseline NIHSS during 24 h of admission were documented as predictors of a good outcome, whereas history of atrial fibrillation and prior stroke, high NIHSS at admission and worsening of symptoms during 24 h of admission, as well as bilateral body involvement were associated with poor outcome.

CONCLUSION

The functional outcomes and the predictors of functional outcomes did not differ from the previously published literature; however, significant differences were observed in the risk factors and etiological profile in our population. These differences are of potential interest to the researchers and clinicians, as they carry important therapeutic and prognostic implications and need to be verified through large prospective studies.

Clinical characteristics, Risk factors, and outcomes of Posterior circulation stroke: A retrospective study between younger and older adults in Saudi Arabia

INTRODUCTION

Posterior circulation stroke (PCS) may be less prevalent than its anterior counterpart but contributes to substantial morbidity and mortality. The aim was to characterize PCS's demographics, clinical presentation, management, and outcomes between younger and older adults in Saudi Arabia.

METHODS

This retrospective cohort study was conducted at two tertiary medical centers in Saudi Arabia between March 2016 and December 2020. All patients who presented with symptoms of posterior circulation stroke and had positive brain imaging were included.

RESULTS

The study involved 160 posterior circulation stroke patients, stratified into two age groups: 71 patients aged 18-59 years and 89 patients aged 60 years and above. The mean age of the entire cohort was 60.9 years, and 77 % were males. Hypertension was more prevalent in the older age group (88 % vs. 69 %, p=0.005), and smoking was significantly higher among younger patients (38 % vs. 15 %; p=0.0009). Only 22.4 % received thrombolysis and/or thrombectomy. Most strokes involved the posterior cerebral artery (45.6 %). Large artery atherosclerosis was the most common subtype. At discharge, younger patients had higher NIHSS compared to older patients.

CONCLUSION

Our investigation of 160 PCS patients in Saudi Arabia uncovers notable trends: a mere 22.4 % received thrombolysis and/or thrombectomy and a significant prevalence of posterior cerebral artery involvement due to large artery atherosclerosis. The study further reveals younger patients disproportionately had severe outcomes. Highlighting the need for improved stroke care and heightened awareness, this research contributes vital data to an underexplored domain, urging further study to optimize care and understand PCS dynamics in Saudi Arabia.

Incidence, clinical features, and outcomes of posterior circulation ischemic stroke: insights from a large multiethnic stroke database

Background

Posterior cerebral circulation ischemic stroke (PCS) comprises up to 25% of all strokes. It is characterized by variable presentation, leading to misdiagnosis and morbidity and mortality. We aim to describe PCS in large multiethnic cohorts.

Methods

A retrospective review of a large national stroke database from its inception on the 1st of January 2014 till 31 December 2020. Incidence per 100,000 adult population/year, demographics, clinical features, stroke location, and outcomes were retrieved. We divided the cohort into patients from MENA (Middle East and North Africa) and others.

Results

In total, 1,571 patients were identified. The incidence of PCS was observed to be rising and ranged from 6.3 to 13.2/100,000 adult population over the study period. Men were 82.4% of the total. The mean age was 54.9 ± 12.7 years (median 54 years, IQR 46, 63). MENA patients comprised 616 (39.2%) while others were 954 (60.7%); of these, the majority (80.5%) were from South Asia. Vascular risk factors were prevalent with 1,230 (78.3%) having hypertension, 970 (61.7%) with diabetes, and 872 (55.5%) having dyslipidemia. Weakness (944, 58.8%), dizziness (801, 50.5%), and slurred speech (584, 36.2%) were the most commonly presenting symptoms. The mean National Institute of Health Stroke Score (NIHSS) score was 3.8 ± 4.6 (median 3, IQR 1, 5). The overall most frequent stroke location was the distal location (568, 36.2%). The non-MENA cohort was younger, less vascularly burdened, and had more frequent proximal stroke location (p < 0.05). Dependency or death at discharge was seen in 39.5% and was associated with increasing age, and proximal and multilocation involvement; while at 90 days it was 27.4% and was associated with age, male sex, and having a MENA nationality (p < 0.05).

Conclusion

In a multiethnic cohort of posterior circulation stroke patients from the MENA region and South Asia, we noted a rising incidence over time, high prevalence of vascular risk factors, and poor outcomes in older men from the MENA region. We also uncovered considerable disparities between the MENA and non-MENA groups in stroke location and outcome. These disparities are crucial factors to consider when tailoring individualized patient care plans. Further research is needed to thoroughly investigate the underlying reasons for these variations.

Pearls for the Emergency Clinician: Posterior Circulation Stroke

BACKGROUND

Posterior circulation (PC) stroke in adults is a rare, frequently misdiagnosed, serious condition that carries a high rate of morbidity.

OBJECTIVE OF THE REVIEW

This review evaluates the presentation, diagnosis, and management of PC stroke in the emergency department (ED) based on current evidence.

DISCUSSION

PC stroke presents most commonly with dizziness or vertigo and must be distinguished from more benign diagnoses. Emergency clinicians should consider this condition in patients with dizziness, even in younger patients and those who do not have traditional stroke risk factors. Neurologic examination for focal neurologic deficit, dysmetria, dysarthria, ataxia, and truncal ataxia is essential, as is the differentiation of acute vestibular syndrome vs. spontaneous episodic vestibular syndrome vs. triggered episodic vestibular syndrome. The HINTS (head impulse, nystagmus, and test of skew) examination can be useful for identifying dizziness presentations concerning for stroke when performed by those with appropriate training. However, it should only be used in patients with continuous dizziness who have ongoing nystagmus. Contrast tomography (CT), CT angiography, and CT perfusion have limited sensitivity for identifying PC strokes, and although magnetic resonance imaging is the gold standard, it may miss some PC strokes early in their course. Thrombolysis is recommended in patients presenting within the appropriate time window for thrombolytic therapy, and although some data suggest endovascular therapy for basilar artery and posterior cerebral artery infarcts is beneficial, its applicability for all PC strokes remains to be determined.

CONCLUSIONS

An understanding of PC stroke can assist emergency clinicians in diagnosing and managing this disease.

Predictive value of serum initial brain natriuretic peptide and troponin on functional prognosis in noncardiogenic patients with anterior and posterior circulation cerebral infarction

BACKGROUND

Brain natriuretic peptide (BNP) and troponin have a close relationship with cardiogenic cerebral embolism (CCE), but their relationship with noncardiogenic patients with anterior circulation ischemia (ACI) and posterior circulation ischemia (PCI) is not clear.

OBJECTIVE

To explore the predictive value of serum initial BNP and troponin on the functional prognosis of patients with noncardiogenic ACI and PCI.

METHODS

Consecutive patients with first-episode cerebral infarction within 12 hours of symptom onset were enrolled in the present 1-year prospective cohort study. Serum levels of BNP and troponin were collected within 12 hours of onset. Infarction location was classified as ACI and PCI by magnetic resonance imaging (MRI). According to the modified Rankin Scale (mRS) score at 90 days after onset, ACI and PCI cases were respectively divided into a good prognosis group (mRS score between 0 and 2) and a poor prognosis group (mRS score between 3 and 6). The general state of health and results of laboratory examinations and other auxiliary examinations of all patients were recorded. Single-factor analysis and multivariate logistic regression analysis were used to assess the relationship between serum levels of BNP, troponin, and functional outcome.

RESULTS

The multivariate logistic regression found that higher levels of initial BNP (odds ratio [OR] = 1.024; 95% confidence interval [CI]: 1.006-1.041; p = 0.007) and C-reactive protein (CRP) (OR = 1.184; 95%CI: 1.024-1.369; p = 0.022) were independent predictors of poor functional prognosis of noncardiogenic PCI at 90 days after onset after adjusting for age, gender, ethnicity, history of hypertension and of diabetes.

CONCLUSIONS

The levels of initial BNP and CRP were related to poor functional outcomes in noncardiogenic PCI patients at 3 months, independent of troponin.

Vertebral Artery Stenoses Contribute to the Development of Diffuse Plaques in the Basilar Artery

Vertebral artery (VA) stenosis is relevant to a high early risk of recurrent stroke and basilar artery (BA) is the most common intracranial site of atherosclerotic lesions. It is important to show predictive risk factors for transient ischemic attack (TIA) or posterior infarctions. The aim of the study is to investigate morphometry and hemodynamics in intracranial vertebral and basilar arteries of health and diseased patients to enhance the risk assessment. Based on the geometrical model reconstructed from CTA images in 343 patients, a transient three-dimensional computational model was used to determine the hemodynamics. Patients were classified in symmetric, asymmetric, hypoplastic, and stenotic groups while patients in the stenotic group were divided into unilateral, bilateral, bifurcation, and tandem stenotic sub-groups. Patients in bilateral, bifurcation, and tandem stenotic sub-groups had significantly lower basilar artery diameters than other groups. Patients in the stenotic group had significantly higher surface area ratio (SAR) of high time-averaged wall shear stress gradient (TAWSSG) and higher incidence of TIAs or posterior infarctions than other groups while patients in the tandem stenotic sub-group had the highest values (SAR-TAWSSG of 57 ± 22% and TIAs or posterior infarction incidence of 54%). The high SAR-TAWSSG is predisposed to induce TIAs or posterior infarction.

Circle of Willis abnormalities and their clinical importance in ageing brains: A cadaveric anatomical and pathological study

The circle of Willis (CW) located at the base of the brain forms an important collateral network to maintain adequate cerebral perfusion, especially in clinical situations requiring compensatory changes in blood flow. Morphopathological changes in the CW may relate to the severity of the symptoms of certain neurodegenerative and cerebrovascular disorders. The purpose of this study was to investigate the CW abnormalities and their clinical importance in ageing brains. The CW was examined macroscopically in 73 formalin-fixed samples to determine the degree of stenosis of each CW component, atherosclerosis of the CW, hypoplasia (threshold diameter < 1 mm), anatomical variations and aneurysms. Age-related neurodegenerative and cerebrovascular pathologies were screened using immunohistopathological techniques on specific neuroanatomical regions based on standard guidelines. The majority of the elderly brains -93 % (68/73) presented at least a single hypoplastic CW component at death. Anatomical variations were mostly identified in communicating arteries, followed by proximal posterior and anterior cerebral arteries. Arterial bifurcations were found to be the predominant sites for cerebral aneurysms. More than 90 % of the elderly brains presented CW atherosclerosis at death. CW abnormalities did not show any strong associations with neurodegenerative pathologies except for an "at risk" significant association observed between Braak's neurofibrillary tangle (NFT) stages 1-VI and CW atherosclerosis grades ≥ mild (p = 0.05). However, a significant association was observed between microscopic infarcts in deep white matter and hypoplasia in communicating arteries with Fisher's exact test (p < 0.05). Overall, CW abnormalities were predominant in the ageing brains, however their relationships to the occurrence and severity of the symptoms of neurodegenerative pathologies were found to be low.

Posterior circulation ischaemic stroke-a review part I: anatomy, aetiology and clinical presentations

Posterior circulation ischaemia is a clinicopathological condition with complex symptomatology associated with an infarction within the vertebrobasilar arterial system. Posterior circulation strokes account for about 20-25% of all ischemic strokes and remain a significant cause of patient disability and mortality. Diagnosis can be challenging because presenting symptoms are often non-focal and because there is a substantial overlap in symptoms and signs of ischaemia in the anterior circulation. Despite better imaging techniques, diagnosis and treatment of life-threatening conditions, such as basilar artery occlusions, are often delayed. Therefore, early detection of symptoms and causes of posterior circulation ischaemia is essential for choosing the most appropriate therapy. In this review, we summarise the anatomy, aetiology, typical presentations and characteristic findings of common strokes resulting from disease in the vertebrobasilar arterial system.

Intravenous Thrombolysis in Posterior Circulation Stroke

Background: Intravenous thrombolysis (IVT) is a standard treatment for both anterior circulation ischemic stroke (ACIS) and posterior circulation ischemic stroke (PCIS). PCIS is a clinical syndrome associated with ischemia-related changes in the territory of the posterior circulation arteries. Embolism is the most common stroke mechanism in posterior circulation. PCIS represents 12–19% of all IVT-treated strokes.

Methods and Results: We searched the PubMed database for assessments of intracerebral hemorrhage (ICH) and clinical outcome in PCIS patients treated with IVT. ICH occurs in 0–6.9% of posterior ischemic stroke depending on the definition of symptomatic ICH, and any ICH in 17–23.4% of posterior ischemic stroke. For patients with PCIS, 38–49% have a favorable outcome (mRS 0–1) after IVT. Better clinical outcomes occur more often in patients with PCIS than in those with ACIS. The mortality rate among PCIS patients treated with IVT ranges from 9 to 19%; it does not differ significantly between PCIS and ACIS.

Conclusions: Up to date, no data about PCIS and IVT are available from RTCs. Based on limited results from retrospective clinical studies and case series, IVT is safer for use in PCIS than in ACIS. Patients with brainstem ischemia, vertebral artery occlusion, and absence of basilar or posterior cerebral artery occlusion could be considered for treatment with IVT even in borderline cases. Time to IVT in PCIS seems to be a less crucial factor than in ACIS. IVT for PCIS may be beneficial even after 4.5 h from symptom onset.

Distribution of perioperative stroke in cardiac surgery

Background and purpose

The recent literature suggests that a cardiac origin in ischaemic stroke is more frequent than previously assumed. However, it is not always clear which patients benefit from additional cardiac investigations if obvious cardiac pathology is absent.

Methods

A single‐center retrospective observational study was performed with 7454 consecutive patients admitted to the intensive care unit after cardiac surgery in the period 2006–2015 and who had postoperative brain imaging. Cerebral imaging was studied for the occurrence of stroke including subtype and involved vascular territory. It was assumed that all perioperative thromboembolic strokes are of cardiac origin. Data obtained from a hospital cohort of consecutive patients who received a diagnosis of ischaemic stroke were used for comparison.

Results

Thromboembolic stroke occurred in 135 cardiac surgery patients in 56 (41%) of whom the posterior cerebral circulation was involved. In the control group, 100 out of 503 strokes (20%) were located in the posterior cerebral circulation. The relative risk for a posterior location for stroke after cardiac surgery compared to patients with ischaemic stroke without prior cardiac surgery was 2.09; 95% confidence interval 1.60–2.72.

Conclusions

Thromboembolic stroke after cardiac surgery occurs twice as often in the posterior cerebral circulation compared to ischaemic strokes in the general population. If confirmed in general stroke cohorts, the consequence of this finding may be that in patients with an ischaemic stroke that involves the posterior cerebral circulation the chance of a cardiac origin is increased and therefore might trigger additional cardiac investigations such as long‐term heart rhythm monitoring or echocardiography.

Vascular Contributions in Alzheimer's Disease-Related Neuropathological Changes: First Autopsy Evidence from a South Asian Aging Population

BACKGROUND

Evidence from various consortia on vascular contributions has been inconsistent in determining the etiology of sporadic Alzheimer's disease (AD).

OBJECTIVE

To investigate vascular risk factors and cerebrovascular pathologies associated in manifestation of AD-related neuropathological changes of an elderly population.

METHODS

Postmortem brain samples from 76 elderly subjects (≥50 years) were used to study genetic polymorphisms, intracranial atherosclerosis of the circle of Willis (IASCW), and microscopic infarcts in deep white matters. From this cohort, 50 brains (≥60 years) were subjected to neuropathological diagnosis using immunohistopathological techniques.

RESULTS

Besides the association with age, the apolipoprotein E ɛ4 allele was significantly and strongly associated with Thal amyloid-β phases ≥1 [odds ratio (OR) = 6.76, 95% confidence interval (CI) 1.37-33.45] and inversely with Braak neurofibrillary tangle (NFT) stages ≥III (0.02, 0.0-0.47). Illiterates showed a significant positive association for Braak NFT stages ≥IV (14.62, 1.21-176.73) and a significant negative association for microscopic infarcts (0.15, 0.03-0.71) in deep white matters. With respect to cerebrovascular pathologies, cerebral small vessel lesions (white matter hyperintensities and cerebral amyloid angiopathy) showed a higher degree of associations among them and with AD-related neuropathological changes (p < 0.05) compared to large vessel pathology (IASCW), which showed a significant association only with Braak NFT stages ≥I (p = 0.050).

CONCLUSION

These findings suggest that besides age, education, and genetic factors, other vascular risk factors were not associated with AD-related neuropathological changes and urge prompt actions be taken against cerebral small vessel diseases since evidence for effective prevention is still lacking.

Predictors for Intracranial Hemorrhage Following Intravenous Thrombolysis in Posterior Circulation Stroke

Intravenous thrombolysis (IVT) is a standard treatment for anterior (ACS) and posterior circulation stroke (PCS). However, due to the low occurrence of PCS and of intracranial hemorrhage (ICH) in PCS, the knowledge about ICH predictors following IVT in PCS is sparse. Our aim was to identify predictors for ICH following IVT in PCS. The set consisted of 1281 consecutive ischemic stroke (IS) patients treated with IVT, out of which 158 (103 males; mean age 65.6 ± 12.3 years) had PCS. Collected data include baseline characteristics, common stroke risk factors, pre-medication, stroke severity, admission blood glucose level, blood pressure and treatment with intravenous antihypertensive therapy before and during IVT, occlusion of arteries, recanalization rate, time to treatment, and clinical outcome at day 90. Overall, 11 (7%) patients had ICH. Atrial fibrillation (p = 0.004), neurological deficit at time of treatment in the National Institutes of Health Stroke Scale (p = 0.016), decreased level of consciousness (p = 0.003), occlusion of basilar artery (p = 0.007), occlusion of PCA (p = 0.001), and additional endovascular therapy (p = 0.001) were identified by logistic regression analysis as significant predictors for ICH in PCS. Patients with ischemic lesion in the brainstem, occlusion of vertebral artery, or absence of basilar and posterior cerebral artery occlusion might be considered for treatment with IVT even in borderline cases. Those patients seem to have less frequently favorable outcomes without an increase in ICH rate. Time to IVT in PCS seems not to influence ICH risk or chances for favorable outcomes as significantly as it does in ACS.

[Cerebral infarctions in vertebrobasilar artery atherosclerosis]

AIM

to obtain more specific information on the morphology and pathogenesis of cerebral infarctions occurring in vertebrobasilar artery (VBA) atherosclerosis.

MATERIAL AND METHODS

Macro- and microscopic investigations of the brain, its arterial system, and heart were conducted in 69 autopsy cases with infarctions located in the vertebrobasilar system (VBS) in atherosclerosis.

RESULTS

69 cases were found to have 206 VBA infarctions of various extent and locations. The detected infarctions were single and multiple in 27 and 42 cases, respectively. The detected infarctions included extensive (n=7), large (n=9), medium (n=63), small deep (lacunar) (n=97), and small superficial (n=30). The brain stem showed lacunar infarctions most frequently (76% of the infarctions at this site). Medium and small infarctions were identified at the same frequency in the cerebral hemispheres and cerebellum. The occurrence of 94% of the extensive and large infarctions was ascertained to be pathogenetically associated with atherothrombotic occlusion of the intracranial arteries in the VBS. 76% of the small infarctions occurred through the mechanism of cerebral vascular insufficiency in tandem atherostenosis of VBAs in conjunction with an additional decrease in cerebral blood flow under the influence of an extracerebral factor (coronary heart disease). Medium infarctions were approximately equifrequently due to the two aforementioned causes and, in some cases, to cardiogenic thromboembolism of VBAs. Infarctions were multiple in most cases; while recent large atherothrombotic infarctions were frequently concurrent with small organized infarctions resulting from tandem atherostenosis of VBAs.

CONCLUSION

This investigation could establish the relationship between the site, extent, and pathogenetic factors of infarctions in the VBA bed in atherosclerosis, as well as the prognostic value of small infarctions as predictors for severe ischemic stroke.

Posterior versus Anterior Circulation Stroke in Young Adults: A Comparative Study of Stroke Aetiologies and Risk Factors in Stroke among Young Fabry Patients (sifap1)

BACKGROUND

Although 20-30% of all strokes occur in the posterior circulation, few studies have explored the characteristics of patients with strokes in the posterior compared to the anterior circulation so far. Especially data on young patients is missing.

METHODS

In this secondary analysis of data of the prospective multi-centre European sifap1 study that investigated stroke and transient ischemic attack (TIA) patients aged 18-55 years, we compared vascular risk factors, stroke aetiology, presence of white matter hyperintensities (WMH) and cerebral microbleeds (CMB) between patients with ischaemic posterior circulation stroke (PCS) and those having suffered from anterior circulation stroke (ACS) based on cerebral MRI.

RESULTS

We diagnosed PCS in 612 patients (29.1%, 407 men, 205 women) and ACS in 1,489 patients (70.9%). Their age (median 46 vs. 47 years, p = 0.205) and stroke severity (modified Rankin Scale: both 2, p = 0.375, Barthel Index 90 vs. 85, p = 0.412) were similar. PCS was found to be more frequent among the male gender (66.5 vs. 60.1% with ACS, p = 0.003). Vertebral artery (VA) dissection was more often the cause of PCS (16.8%) than was carotid artery dissection of ACS (7.9%, p < 0.001). Likewise, small vessel disease (Trial of Org 10172 in Acute Stroke Treatment [TOAST] = 3, PCS: 14.7%, ACS: 11.8%) and stroke of other determined aetiology (TOAST = 4, PCS: 24.5%, ACS: 16.0%) were more frequent in those with PCS. Furthermore, patent foramen ovale (PFO; PCS: 31.1%, ACS: 25.4%, p = 0.029) was more often detected in patients with PCS. In contrast, large-artery atherosclerosis (TOAST = 1, PCS: 15.4%, ACS: 22.2%) and cardio-embolic stroke (TOAST = 2, PCS: 15.6%, ACS: 18.0%) were less frequent in those with PCS (p < 0.001) as were preceding cerebrovascular events (10.1 vs. 14.1%, p = 0.014), TIA (4.8 vs. 7.7%, p = 0.016) and smoking (53.2 vs. 61.0%, p = 0.001). The presence, extent, and location of WMH and CMB did not differ between the 2 groups.

CONCLUSIONS

Our data suggested a different pattern of aetiology and risk factors in young patients with PCS compared to those with ACS. These findings especially call for a higher awareness of VA dissection and potentially for more weight of a PFO as a risk factor in young patients with PCS. Clinical trial registration-URL: http://www.clinicaltrials.gov; NCT00414583.

Relationship Between the Hypersensitive c-Reactive Protein (hs-CRP) Level and the Prognosis of Acute Brainstem Infarction

The objective of this study is to explore the relationship between the hypersensitive c-reactive protein (hs-CRP) level and the prognosis of acute brainstem infarction. Serum levels of hs-CRP were measured in 68 patients with acute brainstem infarction 72 h after disease onset. The hs-CRP levels in the U.S. National Institutes of Health Stroke Scale (NIHSS) score group and in the modified RANKIN scale (mRS) score group were compared. The independent risk factors of brainstem infarction were analyzed using Logistic binary regression. The hs-CRP level was significantly higher in the group with NIHSS >5 compared with the one with NIHSS ≤ 5 (P = 0.004). In the group with mRS > 2, the age, smoking history, and blood glucose level were significantly higher than those in the group with mRS ≤ 2 (P < 0.05), whereas the hs-CRP level was significantly higher (P = 0.001). Age and hs-CRP level were the independent prognostic factors of the brainstem infarction. The serum hs-CRP level is closely related with the severity and prognosis of brainstem infarction, and is an independent risk factor of acute brainstem infarction.

Infratentorial posterior circulation stroke in a Nigerian population: Clinical characteristics, risk factors, and predictors of outcome

Background:

Posterior circulation stroke (PCS), though less common, differs from stroke in anterior circulation in many aspects. Relatively, it portends a poorer prognosis. However, there is a paucity of data from African countries, in particular, where stroke is a menace.

Objective:

The study aimed to evaluate the etiology, clinical characteristics, outcome, and predictors of outcome in a cohort of patients with IPCS in Northwestern Nigeria.

Materials and Methods:

Out of 595 patients with stroke, we prospectively analyzed 57 patients with PCS in a Tertiary Care Center in Kano, Northwestern Nigeria. Patients were analyzed for demographic data, risk factors, clinical characteristics, stroke subtypes, mortality, and predictors of mortality.

Results:

Posterior circulation ischemic stroke accounted for 57 (9.6%) of 595 of all strokes seen in the study period. They comprised 44 males (mean age 47.8 ± 17.7) and 13 females (mean age 46.3 ± 13.7). Overall, their age ranged between 24 and 90 (mean age 47.4 ± 16.7). However, 52.7% of the patients were < 45 years of age. The most common site affected was the cerebellum seen in 33 (57.9%) patients. Hypertension was the most common risk factor (86%). Headache and vertigo were the most common features accounting for 83.6% and 86.3%, respectively. Thirty-eight (66.7%) patients had an ischemic stroke. Twenty-one (36.8%) of the patients died during the 1-month period of follow-up. Independent predictors of death in the study were hyperglycemia on admission and hemorrhagic stroke.

Conclusions:

IPCS occurred in a relatively younger age group. Headache and vertigo were the most common symptoms. The independent predictors of death in the study were hyperglycemia at presentation and hemorrhagic stroke.

Stroke etiology is associated with outcome in posterior circulation stroke

Objective

Stroke research and clinical trials have focused mainly on anterior circulation stroke (ACS). Since clinical characteristics, mechanisms, and outcomes of posterior circulation stroke (PCS) have been reported different from ACS, more PCS studies are required, particularly researching the etiologies, to help establish an optimal management strategy.

Methods

The present study analyzed patients of PCS who were consecutively admitted and registered in Taipei Veterans General Hospital Stroke Registry between 1 January 2012 to 28 February 2014. We demonstrated the distribution of etiologies, compared the clinical characteristics/outcomes among different etiology groups, and used univariate/multivariate analyses to identify the predictors for poor functional outcome (modified Rankin Scale ≥5) at discharge and 3 month.

Results

About 286 patients of PCS were included for analyses. Basilar artery atheromatous branch occlusive disease (BABO, 28.0%) and large artery dissection (25.9%) were the two most common etiologies, followed by large artery atherosclerotic stenosis/occlusion (LAA, 20.6%), cardioembolism (CE, 18.5%) and small vessel disease (7.0%). Age, vascular risk factors, infarct locations and patterns, and outcomes were different among these five etiology groups. Multivariate analyses showed that age >70 y/o (discharge/3 month, OR, 95% CI: 3.05, 1.23–7.56/8.39, 2.32–30.33), admission NIH Stroke Scale >9 (19.50, 8.69–43.75/13.45, 5.59–32.39), and etiology (LAA versus BABO: 5.00, 1.58–15.83/4.00, 1.19–13.4; CE versus BABO: 3.36, 1.02–11.09/4.66, 1.40–15.46) were independently associated with poor functional outcome.

Interpretation

The etiologies of PCS are heterogeneous and shown to be associated with functional outcomes. Our results have shed lights on future pathophysiological research and designs of clinical trials for PCS.

Ischemic posterior circulation stroke: a review of anatomy, clinical presentations, diagnosis, and current management

Posterior circulation strokes represent approximately 20% of all ischemic strokes (1, 2). In contrast to the anterior circulation, several differences in presenting symptoms, clinical evaluation, diagnostic testing, and management strategy exist presenting a challenge to the treating physician. This review will discuss the anatomical, etiological, and clinical classification of PC strokes, identify diagnostic pitfalls, and overview current therapeutic regimens.

Predicting symptomatic intracerebral hemorrhage after intravenous thrombolysis: stroke territory as a potential pitfall

BACKGROUND

Stroke vascular territories may influence response to thrombolysis, although supporting data are limited. The aim of the study was to test the hypothesis that the current available prediction scores might inaccurately estimate the risk of symptomatic intracerebral hemorrhage (SICH) after intravenous thrombolysis in patients with posterior circulation stroke.

METHODS

We applied the Safe Implementation of Thrombolysis in Stroke (SITS) SICH risk score to data from four hospital-based stroke registries. Patients were grouped according to anterior or posterior circulation stroke. The main outcome measure was SICH per various definitions. Performance of the risk score was assessed with the c statistic.

RESULTS

Data of 518 thrombolyzed patients (434 anterior, 84 posterior) were studied. The overall rate of SICH varied from 3.5% to 6.9% depending on the SICH definition. Patients with posterior circulation stroke were less likely to have post-thrombolysis SICH per NINDS (P=0.042), per ECASS II (P=0.013), or any ICH (P=0.001), and their rate of SICH was markedly lower than predicted (1.2% versus 7.1% by the NINDS definition; 0% versus 4.8%, ECASS II; 0% versus 1.6%, SITS-MOST). The SITS SICH risk score shows moderate model discrimination across the SICH definitions, with c statistic ranging from 0.64 to 0.70.

CONCLUSIONS

The risk of SICH after intravenous thrombolysis in patients with posterior circulation stroke was low enough to render the SITS SICH risk score or other similar prediction models unnecessary. Awareness of stroke territory might help clinicians judiciously use the risk assessment models.

Risk Factors and Stroke Mechanisms in Atherosclerotic Stroke

Background and Purpose—

The aim of this study was to investigate differences in risk factors and stroke mechanisms between intracranial atherosclerosis (ICAS) and extracranial atherosclerosis (ECAS) and between anterior and posterior circulation atherosclerosis.

Methods—

A multicenter, prospective, Web-based registry was performed on atherosclerotic strokes using diffusionweighted magnetic resonance imaging and magnetic resonance angiography. Stroke mechanisms were categorized as artery-to-artery embolism, in situ thrombo-occlusion, local branch occlusion, or hemodynamic impairment.

Results—

Onethousand patients were enrolled from 9 university hospitals. Age (odds ratio [OR], 1.033; 95% confidence interval [CI], 1.018–1.049), male gender (OR, 3.399; 95% CI, 2.335–4.949), and hyperlipidemia (OR, 1.502; 95% CI, 1.117–2.018) were factors favoring ECAS (vs ICAS), whereas hypertension (OR, 1.826; 95% CI, 1.274–2.618; P =0.001) and diabetes mellitus (OR, 1.490; 95% CI, 1.105–2.010; P =0.009) were related to posterior (vs anterior) circulation diseases. Metabolic syndrome was a factor related to ICAS (vs ECAS) only in posterior circulation strokes (OR, 2.433; 95% CI, 1.005–5.890; P =0.007). Stroke mechanisms included arterytoartery embolism (59.7%), local branch occlusion (14.9%), in situ thrombo-occlusion (13.7%), hemodynamic impairment (0.9%), and mixed (10.8%). Anterior ICAS was more often associated with artery-to-artery embolism (51.8% vs 34.0%) and less often associated with local branch occlusion (12.3% vs 40.4%) than posterior ICAS ( P <0.001).

Conclusions—

The prevalence of risk factors and stroke mechanisms differ between ICAS and ECAS, and between anterior and posterior circulation atherosclerosis. Posterior ICAS seems to be closely associated with metabolic derangement and local branch occlusion. Prevention and management strategies may have to consider these differences.

Ischemic stroke among the patients with end-stage renal disease who were undergoing maintenance dialysis

PURPOSE

In spite of higher incidence of stroke in end-stage renal disease (ESRD) patients compared to general population, the risk factor for stroke which is specific to ESRD is not fully understood. The ESRD patients who develop stroke may have certain additional risk factors compared to ESRD patients without stroke. We used registered data of Hallym Stroke Registry to elucidate the factors which affect development of ischemic stroke among the dialysis patients.

MATERIALS AND METHODS

We recruited patients with acute ischemic stroke in ESRD patients undergoing maintenance dialysis. Dialysis patients without stroke were selected as control group with age and gender matching. We compared the demographic features, stroke risk factors, and laboratory findings in ESRD patients with or without ischemic stroke.

RESULTS

The total of 25 patients with ESRD developed ischemic stroke. Fifty ESRD patients without stroke were chosen as the control group. The mean age of acute ischemic stroke patients was 59.80±9.94 and male gender was 48%. The most common ischemic stroke subtype was small vessel occlusion (n=12), followed by large artery atherosclerosis (n=7). The patients with stroke had more frequent history of hypertension and higher systolic/diastolic blood pressure at the time of admission than the ESRD patients without stroke. Total cholesterol and LDL-cholesterol levels were significantly lower in the stroke group. In multivariate analysis, LDL-cholesterol was found to be the only risk factor for ischemic stroke.

CONCLUSION

The results of our study reveal that LDL-cholesterol is associated with greater risk for ischemic stroke in the patients on dialysis.

Posterior circulation ischemic stroke-clinical characteristics, risk factors, and subtypes in a north Indian population: a prospective study

BACKGROUND AND PURPOSE

Posterior circulation stroke accounts for approximately 20% of all strokes with varied clinical presentation, which differ from strokes in anterior circulation, with reference to etiology, clinical features, and prognosis. Short penetrating and circumferential branches in the posterior circulation supply the brain stem, thalamus, cerebellum, occipital, and medial temporal lobes.

MATERIALS AND METHODS

We prospectively analyzed 80 participants of posterior circulation ischemic stroke from a registry of 944 participants attending a tertiary care referral university hospital. Patients were analyzed for demographics, stroke risk factors, clinical characteristics, neuroimaging, and stroke subtypes.

RESULTS

Posterior circulation ischemic stroke accounted for 80 (8.5%) of 944 of all strokes and 80 (10.45%) of 765 of ischemic stroke. Sixty-three were males with mean age 51.7 ± 14.4 years. Twenty-one participants were young (defined as age less than 45 years). Hypertension was found to be the most common risk factor (63.75%). Vertigo was the most common clinical symptom reported in 45 (56.25%) cases. Sixty-eight (85%) patients had large artery disease, 8 (10%) had documented cardioembolic source, 3 (3.75%) small artery disease, and 2 (2.5%) vasculitis. Posterior cerebral artery was most commonly involved. Topographically distal intracranial involvement was most frequent (66.25%) followed by proximal (30%) and middle intracranial territory (3.75%).

CONCLUSIONS

Our study demonatrated the occurrence of posterior circulation stroke in relatively younger age group compared to the Western world. We also found higher percentage of large artery disease, while cardioembolism as a less frequent cause of posterior circulation ischemic stroke in North Indian population. Distal territory involvement was most common in our study.

Prevalence of typical circle of Willis and the variation in the anterior communicating artery: A study of a Sri Lankan population

Objective:

To determine the extent of hypoplasia of the component vessels of the circle of Willis (CW) and the anatomical variations in the anterior communicating artery (AcomA) in the subjects who have died of causes unrelated to the brain and compare with previous autopsy studies.

Materials and Methods:

The external diameter of all the arteries forming the CW in 225 normal Sri Lankan adult cadaver brains was measured using a calibrated grid to determine the occurrence of “typical” CWs, where all of the component vessels had a diameter of more than 1 mm. Variations in the AcomA were classified into 12 types based on Ozaki et al., 1977.

Results:

193 (86%) showed “hypoplasia”, of which 127 (56.4%) were with multiple anomalies. Posterior communicating artery (PcoA) was hypoplastic bilaterally in 93 (51%) and unilaterally in 49 (13%). Precommunicating segment of the posterior cerebral arteries (P1) was hypoplastic bilaterally in 3 (2%), unilaterally in 14 (4%), and AcomA was hypoplastic in 91 (25%). The precommunicating segment of the anterior cerebral arteries (A1) was hypoplastic unilaterally in 17 (5%). Types of variations in the AcomA were: single 145 (65%), fusion 52 (23%), double 22 (10%) [V shape, Y shape, H shape, N shape], triplication 1 (0.44%), presence of median anterior cerebral artery 5 (2%), and aneurysm 1 (0.44%).

Conclusion:

The occurrence of “typical” CW in autopsy brains was rare. Further studies would be necessary to determine if these anatomical variations could predispose to cerebral ischemia and premature stroke in the Sri Lankan population.

Childhood Posterior Circulation Arterial Ischemic Stroke

Background and Purpose— Limited data exist on childhood posterior circulation arterial ischemic stroke (PCAIS). We describe clinical and radiological features of childhood PCAIS to determine whether there are differences in infarct topography, vascular abnormalities, risk factors, and stroke subtypes when compared to adults.

Methods— Children with radiologically confirmed PCAIS were prospectively identified from August 2002 to February 2008. Infarcts were divided into proximal, middle, and distal posterior circulation segments utilizing an adult topographical classification system. Vascular abnormalities were described in terms of location, severity, and evolution over time. A pediatric modification of the TOAST classification system was used to define stroke subtypes.

Results— Twenty seven (37%) of 73 children recruited to our registry had 34 radiologically confirmed PCAIS events. Infarct location was distal (25), middle (2), proximal (1), and multiple segments (6). Fourteen events were associated with single infarcts and 20 were associated with multiple infarcts. Magnetic resonance angiography was abnormal in 16 of 25 children with PCAIS at presentation with stenosis (8) or occlusion (8). Vascular lesions progressed (5), transiently worsened before stabilizing (2), remained stable or improved (8), or normalized (1) over 12 months. Stroke subtypes included nonprogressive steno-occlusive cerebral arteriopathy (9), cardioembolic (4), dissection (3), Moyamoya syndrome (3), other determined (4), probable (1), and undetermined etiology (3). Fifty-two percent of children had recurrent posterior (6) or anterior (8) strokes.

Conclusions— Nonprogressive arteriopathies are the most common cause of childhood PCAIS, usually affecting distal segments. Atherosclerosis-related risk factors do not play an important role in stroke causation. PCAIS is frequently associated with recurrent events.

Seizures and epilepsy in patients with a posterior circulation infarct

Seizures occur mainly in patients with cortical infarcts in the anterior circulation. Those related to a posterior circulation infarct (POCI) are considered rare. This study investigated the characteristics of patients with seizures related to a POCI. A total of 180 consecutive patients admitted with a POCI had a 2- to 7-year follow-up; 24 of them (13.6%) developed seizures. Vascular risk factors, etiology and extension of the infarct, degree of neurologic impairment, and outcome were compared in the patients with and without seizures. Complex partial type seizure was the most common presentation. Stroke characteristics were largely the same in the patients with and without seizures. History of a previous stroke was noted in 62.5% of the seizure group and in 17.9% of the nonseizure group (P < .001). Clinical outcome was worse in the seizure group (P = .004). The relative incidence of seizures in patients with a POCI was not lower than that in the overall stroke population. The high incidence of recurrent stroke is the main risk factor for seizures in patients with a POCI. The seizures themselves are responsible for the increased dependence rate.

Ischaemic posterior circulation stroke in State of Qatar

BACKGROUND

Ischaemic stroke features may show regional differences. Posterior circulation stroke (PCS) is of special interest, as symptomatology, course and outcome are usually different and complex. No significant studies or registries have reported on the characteristics and outcomes of PCS in our region.

METHODS

We prospectively collected data of 116 patients with PCS admitted from 2005 through 2008 in the only stroke admitting hospital in Qatar. Demographics, risk factors, clinical signs/symptoms, pattern of presentation, aetiology, imaging features, complications and outcome at discharge and follow-up were recorded.

RESULTS

Mean age was 53 years with 25% aged < or = 45, 85% were males. Demographically 47% were Arabs and 51% of South-Asian origin. Mean duration from onset to presentation was 29 h. Major risk factors were obesity (66%) and hypertension (61%). Minimal or fluctuating symptoms were present in 64%, while 9% had maximal deficit at onset. Thirty nine per cent had lesions in proximal territory and 23% in multiple territories. Around 41% had no occlusion, 16% had vertebro-basilar, 16% vertebral, 8% basilar occlusion. Etiologically 53% patients had large artery disease, 16% small vessel disease, and 17% cardioembolism. Seventy per cent of patients were discharged home, while 10% expired. Modified Rankin score (mRS) at discharge was < or = 2 in 53% and > or = 4 in 13% patients. At 30-day follow-up, 68% had mRS of < or = 2. Ninety-day survival status showed 89% alive with mRS < or = 2 in 73%.

CONCLUSION

The aetiology and lesion topography of PCS in this heterogeneous population differs from the pattern observed in other populations.