William Hu

Serum Glucose Level and Diabetes Predict Tissue Plasminogen Activator–Related Intracerebral Hemorrhage in Acute Ischemic Stroke

BACKGROUND AND PURPOSE Five pretreatment variables (P<0.1 univariate analysis), including serum glucose (>300 mg/dL), predicted symptomatic intracerebral hemorrhage (ICH) in the National Institute of Neurological Disorders and Stroke rtPA trial. We retrospectively studied stroke patients treated <3 hours from onset with intravenous rtPA at 2 institutions to evaluate the role of these variables in predicting ICH. METHODS Baseline characteristics, including 5 prespecified variables (age, baseline glucose, smoking status, National Institutes of Health Stroke Scale [NIHSS] score, and CT changes [>33% middle cerebral artery territory hypodensity]), were reviewed in 138 consecutive patients. Variables were evaluated by logistic regression as predictors of all hemorrhage (including hemorrhagic transformation) and symptomatic hemorrhage on follow-up CT scan. Variables significant at P<0.25 level were included in a multivariate analysis. Diabetes was substituted for glucose in a repeat analysis. RESULTS Symptomatic hemorrhage rate was 9% (13 of 138). Any hemorrhage rate was 30% (42 of 138). Baseline serum glucose (5.5-mmol/L increments) was the only independent predictor of both symptomatic hemorrhage [OR, 2.26 (CI, 1.05 to 4.83), P=0.03] and all hemorrhage [OR, 2.26 (CI, 1.07 to 4.69), P=0.04]. Serum glucose >11.1 mmol/L was associated with a 25% symptomatic hemorrhage rate. Baseline NIHSS (5-point increments) was an independent predictor of all hemorrhage only [OR, 12.42 (CI, 1.64 to 94.3), P=0.01]. Univariate analysis demonstrated a trend for nonsmoking as a predictor of all hemorrhage [OR, 0.45 (CI, 0.19 to 1. 08), P=0.07]. Diabetes was also an independent predictor of ICH when substituted for glucose in repeat analysis. CONCLUSIONS Serum glucose and diabetes were predictors of ICH in rtPA-treated patients. This novel association requires confirmation in a larger cohort.

Intracranial thrombus extent predicts clinical outcome, final infarct size and hemorrhagic transformation in ischemic stroke: the clot burden score.

Background In ischemic stroke, functional outcomes vary depending on site of intracranial occlusion. We tested the prognostic value of a semiquantitative computed tomography angiography-based clot burden score. Methods Clot burden score allots major anterior circulation arteries 10 points for presence of contrast opacification on computed tomography angiography. Two points each are subtracted for thrombus preventing contrast opacification in the proximal M1, distal M1 or supraclinoid internal carotid artery and one point each for M2 branches, A1 and infraclinoid internal carotid artery. We retrospectively studied patients with disabling neurological deficits (National Institute of Health Stroke Scale score ≥ 5) and computed tomography angiography within 24-hours from symptom onset. We analyzed percentages independent functional outcome (modified Rankin Scale score ≤ 2), final infarct Alberta Stroke Program Early Computed Tomography Score and parenchymal hematoma rates across categorized clot burden score groups and performed multivariable analysis. Results We identified 263 patients (median age 73-years, National Institute of Health Stroke Scale score 10, onset-to-computed tomography angiography time 165 min). Clot burden score < 10 was associated with reduced odds of independent functional outcome (odds ratio 0.09 for clot burden score ≤5; odds ratio 0.22 for clot burden score 6–7; odds ratio 0.48 for clot burden score 8–9; all versus clot burden score 10; P <0.02 for all). Lower clot burden scores were associated with lower follow-up Alberta Stroke Program Early CT Scores (P <0.001) and higher parenchymal hematoma rates (P = 0.008). Inter-rater reliability for clot burden score was 0.87 (lower 95% confidence interval 0.71) and intra-rater reliability 0.96 (lower 95% confidence interval 0.92). Conclusion The quantification of intracranial thrombus extent with the clot burden score predicts functional outcome, final infarct size and parenchymal hematoma risk acutely. The score needs external validation and could be useful for patient stratification in stroke trials.

Hyperperfusion Syndrome: Toward a Stricter Definition

OBJECTIVEHyperperfusion syndrome is a rare and potentially devastating complication of carotid endarterectomy or carotid artery angioplasty and stenting. With the advent of new imaging techniques, we reviewed our experience with this phenomenon. METHODSThis report is a retrospective review of 129 consecutive cases of carotid endarterectomy performed between June 1, 2000, and May 31, 2002, and 44 consecutive cases of carotid artery angioplasty and stenting performed between January 1, 1997, and May 31, 2002. We specifically searched for examples of patients who developed postprocedural nonthrombotic neurological deficits that typified the hyperperfusion syndrome. RESULTSSeven cases of hyperperfusion syndrome occurred, four after endarterectomy (3.1% of carotid endarterectomy cases) and three after stenting (6.8% of stenting cases). The cases of hyperperfusion were classified as presenting with 1) acute focal edema (two cases with stroke-like presentation, attributable to edema immediately after revascularization), 2) acute hemorrhage (two cases of intracerebral hemorrhage immediately after stenting and one case immediately after endarterectomy), or 3) delayed classic presentation (two cases with seizures, focal motor weakness, and/or late intracerebral hemorrhage at least 24 hours after endarterectomy). CONCLUSIONHyperperfusion syndrome may be more common and more variable in clinical presentation than previously appreciated.

Interobserver Variation of ASPECTS in Real Time

Background— The Alberta Stroke Program Early CT Score (ASPECTS) has been used to quantify early ischemic changes on computed tomography (CT) brain scans of acute stroke patients. We sought to assess the reliability of the score when performed in real time as compared with an expert rating performed at a later time point. Methods— Two hundred fourteen patients presenting with acute ischemic stroke or transient ischemic attack were prospectively recruited if they had a brain CT scan performed within 12 hours of symptom onset. Each scan was read for ASPECTS prospectively by the treating physician and later by 1 expert reader. A weighted kappa statistic was used to determine the interobserver agreement. Results— The median baseline National Institutes of Health Stroke Scale score was 5 (range: 0 to 32) and the median time to CT scan was 152 minutes (range: 22 to 769). The interobserver agreement between ASPECTS performed in real time and expert ASPECTS was substantial (κw=0.69). The mean difference between real-time ASPECTS and expert ASPECTS was 0 (SD: 1.1). Conclusions— ASPECTS is a reliable clinical scale for rating early ischemic changes on CT when performed in real time.

A pediatric case of reversible segmental cerebral vasoconstriction

BACKGROUND Reversible segmental cerebral vasoconstriction (RSCV) is a recognizable clinical and radiographic syndrome consisting of thunderclap headache with or without focal neurological symptoms combined with reversible segmental vasoconstriction of proximal cerebral blood vessels. METHODS We report a case of reversible segmental cerebral vasoconstriction in a child. RESULTS A healthy 13-year-old boy experienced the sudden onset of a severe, diffuse headache upon surfacing from a deep dive in a swimming pool. Severity was maximal at the onset and improved over several hours. The same headache recurred three times over the next four days and a low baseline headache persisted throughout. Vomiting occurred once and mild photo/osmophobia were reported but throbbing, aura, or autonomic symptoms were absent. Focal neurological signs or symptoms were absent and he denied previous history of headaches, medications, drugs, or trauma. Two normal CT scans were performed within hours of separate headaches. Cerebrospinal fluid study on day 5 was bloody with no xanthochromia. MRI/MRA/MRV of the brain and vasculitic work-up were normal. Cerebral angiography on day 6 demonstrated smooth narrowing of multiple proximal cerebral vessels including supraclinoid internal carotid artery (ICA), M1, and A1 on the right and M1 on the left. By ten days, the patients headaches had resolved and repeat angiography was normal. CONCLUSION RSCV should be considered in a child with thunderclap headache.

Calcification and endothelialization of thrombi in acute stroke

We report chronic histopathological features in thrombi mechanically retrieved from five acute ischemic stroke patients with a median age of 68 years and a median pretreatment National Institutes of Health Stroke Scale score of 13. Early endothelialization occurred over and within the thrombus, and calcifications were seen, in addition to the usual acute laminar fibrin, intervening red blood cells, and neutrophils. The effectiveness of tissue plasminogen activator in clot dissolution might be affected by these features, if extensive. Thrombus composition could critically determine the success of chemical thrombolysis. Our results should stimulate the development of imaging modalities to determine thrombus composition. Ann Neurol 2008

Combined full‐dose IV and endovascular thrombolysis in acute ischaemic stroke

Background There is an increasing trend to treating proximal vessel occlusions with intravenous–inter-arterial (IV-IA) thrombolysis. The best dose of IV tissue plasminogen activator (tPA) remains undetermined. We compared the combination of full-dose IV recombinant tissue plasminogen activator (rtPA) and IA thrombolytic therapy to IA therapy. Methods Between 2002 and 2009, we reviewed our computed tomographic angiography database for patients who received full-dose intravenous rtPA and endovascular therapy or endovascular therapy alone for acute ischaemic stroke treatment. Details of demographics, risk factors, endovascular procedure, and symptomatic intracranial haemorrhage were noted. Modified Rankin Scale ≤2 at three-months was used as good outcome. Recanalization was defined as Thrombolysis in Myocardial Ischaemia 2–3 flow on angiography. Results Among 157 patients, 104 patients received IV-IA treatment and 53 patients underwent direct IA therapy. There was a higher recanalization rate with IV-IA therapy compared with IA alone (71% vs. 60%, P < 0·21) which was driven by early recanalization after IV rtPA. Mortality and independent outcome were comparable between the two groups. Symptomatic intracranial haemorrhage occurred in 8% of patients (12% in the IA group, 7% in the IV-IA group) but was more frequent as the intensity of intervention increased from device alone to thrombolytic drug alone to device plus thrombolytic drug(s). Recanalization was a strong predictor of reduced mortality risk ratio (RR) 0·48 confidence interval95 0·27–0·84) and favourable outcome (RR 2·14 confidence interval95 1·3–3·5). Conclusions Combined IV-IA therapy with full-dose intravenous rtPA was safe and results in good recanalization rates without excess symptomatic intracranial haemorrhage. Testing of full-dose IV tPA followed by endovascular treatment in the IMS3 trial is justified.

Tumor-to-tumor metastasis: esophageal carcinoma metastatic to an intracranial paraganglioma

Tumor-to-tumor metastasis (TTM) is a relatively rare but well-documented phenomenon. The authors report a unique case of esophageal carcinoma metastatic to an intracranial paraganglioma. A sellar and suprasellar tumor was found using MR imaging in an 81-year-old man who presented with a 3-week history of progressive headache and blurred vision. A subtotal excision of the tumor was achieved. Histopathological examination of the tumor disclosed a neoplasm with two distinct components: one showing the classic Zellballen pattern of a paraganglioma, the other exhibiting malignant features leading to the diagnosis of a poorly differentiated carcinoma metastatic to a sellar/suprasellar paraganglioma. The primary esophageal carcinoma was not uncovered until 2 months later, after the patient presented with upper gastrointestinal bleeding. The patient died 4 months after initial presentation. This case expands the spectrum of TTM, and emphasizes the importance of TTM in the practice of pathology.

MRI of ischemic stroke in canines: Applications for monitoring intraarterial thrombolysis

To describe a canine embolic stroke model that is appropriate for endovascular procedure evaluations and develop local cerebral blood flow (CBF) maps to monitor the progression of stroke and thrombolysis. In the future, MR may displace X‐ray imaging in some endovascular procedures, such as intraarterial (IA) thrombolysis for stroke therapy, due to increased monitoring capabilities. For MR to attain its full potential in endovascular therapy, the development of appropriate disease models and monitoring techniques is essential.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL).

Symptoms • Subcortical ischemic events (85% of affected individuals) o Transient ischemic attacks (TIAs) o Strokes • Cognitive defects/dementia (75% of affected individuals) • Migraines (35% of affected individuals) • Psychiatric disorders (33% of affected individuals) • Epilepsy (10% of affected individuals) Prognosis  CADASIL is a progressive disease with no known effective treatment  Disease progression is more rapid in males than females  Median age for loss of ambulation is 60 years  Median age of death is 68 years