Asymptomatic hemorrhage after thrombolysis may not be benign: prognosis by hemorrhage type in the Canadian alteplase for stroke effectiveness study registry.

Background And Purpose: There is ongoing controversy about the impact of hemorrhagic transformation after thrombolysis on long-term functional outcome. We sought to study the relation between the type of hemorrhagic transformation on CT scans and functional outcome.

Methods: Data were obtained from the Canadian Alteplase for Stroke Effectiveness Study.

How well does ASPECTS predict the outcome of acute stroke treated with IV tPA?

The authors measured the association of early ischemic change on CT scan, measured using the Alberta Stroke Programme Early CT score (ASPECTS), and functional outcome in 825 patients with anterior circulation stroke treated with IV thrombolysis within 3 hours of onset. ASPECTS predicted outcome in a graded fashion (linearly for ASPECTS 6 through 10; pattern ill-defined for ASPECTS 0 through 5) but discriminated individual outcomes weakly. Except perhaps when early ischemic change is extensive, clinicians should not estimate prognosis using ASPECTS alone.

Insular cortical ischaemia does not independently predict acute hypertension or hyperglycaemia within 3 h of onset.

Objectives: To test the hypothesis that insular cortical ischaemia is associated with acute hypertension and hyperglycaemia.

Methods: From the Canadian Activase for Stroke Effectiveness Study, which included only patients treated with thrombolysis hyperacutely (ie, within 3 h of onset of stroke), 966 patients were identified with ischaemia affecting (n = 685), or sparing (n = 281), the insular cortex. Demographic and clinical data, pretreatment indices of blood pressure, blood glucose, atrial fibrillation, and clinical imaging and outcome measures were compared between the two groups.

Imaging of the brain in acute ischaemic stroke: comparison of computed tomography and magnetic resonance diffusion-weighted imaging.

Background And Objectives: Controversy exists about the optimal imaging technique in acute stroke. It was hypothesised that CT is comparable with DWI, when both are read systematically using quantitative scoring.

Methods: Ischaemic stroke patients who had CT within six hours and DWI within seven hours of onset were included.

ASPECTS on CTA source images versus unenhanced CT: added value in predicting final infarct extent and clinical outcome.

Background And Purpose: The Alberta Stroke Program Early CT Score (ASPECTS) is a grading system to assess ischemic changes on CT in acute ischemic stroke. CT angiography-source images (CTA-SI) predict final infarct volume. We examined whether the final infarct ASPECTS and clinical outcome were more related to acute CTA-SI ASPECTS than to the acute noncontrast CT (NCCT) ASPECTS.

The probability of middle cerebral artery MRA flow signal abnormality with quantified CT ischaemic change: targets for future therapeutic studies.

Objectives: In this study we define the probability of vascular abnormality in the middle cerebral artery (MCA) territory according to the extent of ischaemic change seen using computed tomography (CT). We assessed the sensitivity and specificity of the hyperdense middle cerebral artery (HMCA) and the "dot" sign using magnetic resonance angiography (MRA).

Methods: Patients presenting with ischaemic stroke had a CT scan (<6 h) prior to MRI (<7 h).

Is intravenous recombinant tissue plasminogen activator (rt-PA) safe for use in patients over 80 years old with acute ischaemic stroke? - The Calgary experience.

Background: Acute ischaemic stroke is common in older people. There is one licensed acute treatment, intravenous recombinant tissue plasminogen activator, but little information is available on its safety in over 80 year olds.

Design: Review of prospectively collected data on 62 consecutive patients, aged 80 years and over, treated with recombinant tissue plasminogen activator in a tertiary centre.

Mild neurological symptoms despite middle cerebral artery occlusion.

Background And Purpose: Only a small percentage of stroke patients are treated with thrombolytic therapy. We sought to determine whether vessel occlusion in mild strokes represented a new target population for interventional therapy.

Methods: We imaged 106 acute stroke patients with MRI.

CT assessment of conjugate eye deviation in acute stroke.

Conjugate eye deviation seen on clinical examination helps to localize pathology in acute ischemic stroke. Eye deviation can also be assessed on a CT head scan. The authors found that CT eye deviation reliably lateralizes to the ischemic hemisphere (positive predictive value 93%) without reference to clinical examination.

Use of the Alberta Stroke Program Early CT Score (ASPECTS) for assessing CT scans in patients with acute stroke.

Background And Purpose: Clinicians are insecure reading CT scans by using the one-third rule for acute middle cerebral artery stroke (1/3 MCA rule) before treating patients with recombinant tissue plasminogen activator. The 1/3 MCA rule is a poorly defined volumetric estimate of the size of cerebral infarction of the MCA. A 10-point quantitative topographic CT scan score, the Alberta Stroke Program Early CT Score (ASPECTS), is described and illustrated.

Hyperdense sylvian fissure MCA "dot" sign: A CT marker of acute ischemia.

Background And Purpose: The hyperdense appearance of the main middle cerebral artery (HMCA) is now a familiar early warning of large cerebral infarction, brain edema, and poor prognosis. This article describes the hyperdensity associated with embolic occlusion of branches of the middle cerebral artery in the sylvian fissure (MCA "dot" sign). We define it and determine its incidence, diagnostic value, and reliability.

Computed tomography evaluation of patients with chronic headache.

Objective: To determine whether the rate of detecting a tumour, arteriovenous malformation (AVM) or aneurysm with the use of enhanced or unenhanced computed tomography (CT) is significant in patients with chronic headache and to calculate the cost.

Design: Case series.

Setting: Chronic headache clinic at a tertiary care referral centre.

Cognitive functioning in long-term survivors of high-grade glioma.

In a pilot study, two groups of patients with malignant glioma underwent sequential neuropsychological evaluations after successful tumor treatment. Group 1 included nine patients treated from 1981 to 1985; all patients received irradiation and eight underwent chemotherapy. The baseline neuropsychological assessment was performed 1 to 63 months after tumor diagnosis, with follow-up evaluations at irregular intervals over the next 3 to 7 years.

Steroid-induced CT changes in patients with recurrent malignant glioma.

The magnitude and time course of steroid-induced CT changes were analyzed in 11 patients with recurrent malignant glioma. CTs were obtained before and at regular intervals after starting dexamethasone (16 mg/d). Midline shift, ventricular compression, edema, enhancement intensity, and the size of the enhancing mass often improved with steroid treatment.

The significance of internal carotid artery occlusion shown by i.v. digital subtraction angiography.

A retrospective review of 493 IV digital subtraction angiography examinations performed for cervicocerebral vascular disease revealed 27 apparent occlusions of the internal carotid artery. We identified 20 patients whose occlusions did not warrant further investigation. Fourteen occlusions were on the asymptomatic side, two were in patients who preferred medical treatment, two were in patients unsuitable for carotid endarterectomy, and two patients with bihemispheric transient ischemic attacks were treated for the contralateral carotid.

Postoperative contrast enhancement in patients with brain tumor.

Contrast enhancement resulting from surgical trauma may mimic residual enhancing tumor, thereby complicating the interpretation of postoperative computed tomographic scans. We assessed the natural history of postoperative enhancement in 10 patients with brain tumor. Contrast enhancement distinguishable from residual enhancing tumor appeared along the operative margin following tumor resections but not lobectomies.

Intracranial metrizamide mimicking white matter disease.

We report two patients in whom brain penetrance of grey matter by metrizamide, introduced for myelography thirty hours earlier, mimics the periventricular lucency of white matter disease on cranial computed tomography.

Doppler flow maps of the carotid artery compared with the findings on angiography.

One noninvasive method of evaluating the condition of the carotid arteries is by the Echoflow Doppler device, which produces colour-coded images of the flow pattern in the arteries. Normal velocities are represented in red, accelerated flow in yellow and turbulences in blue. The authors present the results of Echoflow studies in 317 patients who also underwent cerebral angiography.