Background and Purpose-Quantification of early ischemic changes (EIC) may predict functional outcome in patients with basilar artery occlusion (BAO). We tested the validity of a novel CT score, the posterior circulation Acute Stroke Prognosis Early CT score (pc-ASPECTS). Methods-Pc-ASPECTS allots the posterior circulation 10 points. Two points each are subtracted for EIC in midbrain or pons and 1 point each for EIC in left or right thalamus, cerebellum or PCA-territory, respectively. We studied 2 different populations: (1) patients with suspected vertebrobasilar ischemia and (2) patients with BAO. We applied pc-ASPECTS to noncontrast CT (NCCT), CT angiography source images (CTASI), and follow-up image by 3-reader consensus. We calculated sensitivity for ischemic changes and analyzed the predictivity of pc-ASPECTS for independent (modified Rankin Scale [mRS] score Յ2) and favorable (mRS score Յ3) outcome. Results-Of 130 patients with suspected vertebrobasilar ischemia, 72% (94) had posterior circulation stroke, 8% (10) transient ischemic attack, and 20% (26)

Irradiation of mammalian cells can cause cell cycle perturbations and apoptotic cell death. We have investigated the modulation of these physiologic end points by growth factor stimulation: irradiation of a murine hematopoietic cell line in the presence of interlekin-3 (IL-3) induces G 1 arrest, and irradiation in the absence of IL-3 results in rapid apoptotic cell death. Both of these end points are dependent on p53. Transient removal of IL-3 at the time of irradiation results in decreased clonogenic survival of irradiated cells. The removal of IL-3 results in a failure of the irradiated cells to arrest at the G1 checkpoint, despite induction of p53 and p21 wAn/cxv~, and then the cells enter S-phase where they undergo apoptosis. There are no cytokine-related changes in Bcl-2, Bax, or Bcl-x protein levels that could account for the modulation of G~ arrest versus apoptosis by growth factors. In contrast, rapid p53-independent alterations of basal levels of gadd45 and p21 wAFl/clvl expression are linked to IL-3 withdrawal, suggesting a potential mechanism for this modulation. Constitutive activation of cytokine-like pathways with induced expression of v-Src or activated c-Raf inhibits the radiation-induced apoptosis and the alterations in p21 wAn/clvl and gadd45 expression. These observations suggest additional molecular mechanisms that can contribute to the development of radioresistance and resistance to apoptosis during tumorigenesis and provide an explanation for the observed lack of p53 mutations in some tumor types. In addition, these data suggest that oncogenic changes occurring during multistep tumorigenesis could be classified as those that either enhance or decrease apoptosis tendencies.

No abstract

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.

Background and Purpose-We investigated whether computed tomography (CT) perfusion-derived cerebral blood flow (CBF) and cerebral blood volume (CBV) could be used to differentiate between penumbra and infarcted gray matter in a limited, exploratory sample of acute stroke patients. Methods-Thirty patients underwent a noncontrast CT (NCCT), CT angiography (CTA), and CT perfusion (CTP) scan within 7 hours of stroke onset, NCCT and CTA at 24 hours, and NCCT at 5 to 7 days. Twenty-five patients met the criteria for inclusion and were subsequently divided into 2 groups: those with recanalization at 24 hours (nϭ16) and those without (nϭ9). Penumbra was operationally defined as tissue with an admission CBF Ͻ25 mL ⅐ 100 g Ϫ1 ⅐ min

We examined whether the presence of diffusion-weighted imaging (DWI) lesions and vessel occlusion on acute brain magnetic resonance images of minor stroke and transient ischemic attack patients predicted the occurrence of subsequent stroke and functional outcome. 120 transient ischemic attack or minor stroke (National Institutes of Health Stroke Scale < or = 3) patients were prospectively enrolled. All were examined within 12 hours and had a magnetic resonance scan within 24 hours. Overall, the 90-day risk for recurrent stroke was 11.7%. Patients with a DWI lesion were at greater risk for having a subsequent stroke than patients without and risk was greatest in the presence of vessel occlusion and a DWI lesion. The 90-day risk rates, adjusted for baseline characteristics, were 4.3% (no DWI lesion), 10.8% (DWI lesion but no vessel occlusion), and 32.6% (DWI lesion and vessel occlusion) (p = 0.02). The percentages of patients who were functionally dependent at 90 days in the three groups were 1.9%, 6.2%, and 21.0%, respectively (p = 0.04). The presence of a DWI lesion and a vessel occlusion on a magnetic resonance image among patients presenting acutely with a transient ischemic attack or minor stroke is predictive of an increased risk for future stroke and functional dependence.

Risk of recurrent stroke and functional impairment after a TIA or minor stroke can be accurately predicted by a scoring system that utilizes both clinical and MRI information. The ABCD(2)+MRI score is simple and its components are commonly available during the time of admission.

Background and Purpose-The Penumbra Pivotal Stroke Trial reported a 25% good outcome (modified Rankin scale score Յ2) despite an 81% recanalization rate. We evaluated the association of a favorable initial noncontrast CT and a short time to recanalization in predicting good outcome. Methods-Data were from the Penumbra Pivotal Stroke Trial. Baseline scans were evaluated by 2 experienced readers blinded to outcomes using ASPECTS. ASPECTS scores were dichotomized into Ͼ7 and Յ7 for primary analysis. Data on degree of recanalization based on thrombolysis in myocardial infarction scores, stroke onset to recanalization, and CT to recanalization times were obtained. Primary outcome was modified Rankin scale score Յ2 at 3 months. Results-Median baseline NIHSS was 18 (range, 8 -34) and median baseline ASPECTS score was 6 (range, 0 -10); 81.2% achieved recanalization (thrombolysis in myocardial infarction, 2-3) and (27.7%) achieved good outcome. Good outcome was significantly higher in the ASPECTS score Ͼ7 group when compared to the ASPECTS score Յ7 group (50% vs 15%; RR, 3.3; 95% CI, 1. Pϭ0.0001). No patient with an ASPECTS score Յ4 (nϭ28) or without recanalization (nϭ16) had a good outcome. There was an interaction between baseline ASPECTS score (Ͼ7 and Յ7) and onset to recanalization time (Յ300 minutes and Ͼ300 minutes) in predicting good outcome (Pϭ0.06). Conclusion-Patients with baseline CT ASPECTS score Յ4 do not benefit from recanalization. Fast recanalization may benefit patients with evident damage on the CT scan (ASPECTS score Ͼ4). Overall, patients benefit the most with early recanalization and a favorable baseline CT scan (ASPECTS score Ͼ7). (Stroke. 2011;42:93-97.)Key Words: injections Ⅲ intra-arterial Ⅲ numerical data Ⅲ physiopathology Ⅲ statistics Ⅲ stroke Ⅲ treatment outcome T reatment of acute ischemic stroke is aimed at salvaging potentially viable ischemic brain by recanalizing the occluded artery and restoring anterograde perfusion. Final infarct size is reduced and functional outcomes are better if this is achieved rapidly. 1-5 Although intravenous (IV) tissue plasminogen activator has become the standard of care in acute ischemic stroke treatment up to 4.5 hours from stroke onset, 6 it is limited by low recanalization rates in proximal occlusions. 7,8 Endovascular techniques have shown high recanalization rates not seen with intravenous thrombolysis, but have shown relatively poor clinical outcomes. 9 -13 In the Multi MERCI trial, 11 an arterial recanalization rate of 69.5% but good clinical outcome of only 36% with a mortality of 34% was noted. The Penumbra Pivotal Stroke Trial 14 demonstrated an 81.6% recanalization rate with only 25% good clinical outcome. In these studies, patients with recanalization fared better than those who did not.We have shown previously that patients with favorable baseline CT scans, defined by an Alberta Stroke Program Early CT Scale 15 (ASPECTS) score Ͼ7, were 3-fold more likely to achieve independent functional outcome with endovascular treatment when compared to pl...