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 angiographysource images (CTA- SI) predict final infarct v...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 angiographysource 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. Methods - ASPECTS was assigned by 2 raters on the acute NCCT, CTA- SI, and follow- up imaging. The mean baseline ASPECTS of acute NCCT and CTA- SI was compared with the follow- up ASPECTS. Rate ratios (RRs) were used to quantify the relationship between the dichotomized baseline ASPECTS (categorized as 0 to 7 versus 8 to 10) and favorable patient outcome. Results - Thirty- nine patients were recruited. Proximal occlusion (internal carotid artery or middle cerebral artery) was seen in 62% , M2 occlusion in 18% , and no occlusion was seen in 20% of patients. The median time between symptom onset and imaging was 1.9 (1.2 to 2.5) hours. There was a significantly larger difference of 1.4 between the mean baseline NCCT and CTA- SI ASPECTS in patients who had more ischemic changes (follow up ASPECTS=0 to 3) than a difference of 0.6 in patients who had near- to- normal CT scans (follow- up ASPECTS=8 to 10). The rate of favorable outcome for acute NCCT ASPECTS of 8 to 10 was 51.8% versus 25.0% for 0 to 7 (RR, 2.1, 95% Cl: 0.7 to 5.9, P=0.12). For acute CTA- SI ASPECTS of 8 to 10, the rate of favorable outcome was 58.8% versus 31.8% for 0 to 7 (RR. 1.8, 95% CI: 0.9 to 3.8, P=0.09). Conclusions - CTA- SI ASPECTS provides added information in the prediction of final infarct size.展开更多
Background: In a general population of patients with stroke, the rate of new MRI lesions at 1 week was much higher than expected. With patients with minor stroke and TIA having a higher risk of recurrent clinical even...Background: In a general population of patients with stroke, the rate of new MRI lesions at 1 week was much higher than expected. With patients with minor stroke and TIA having a higher risk of recurrent clinical events, the authors examined whether patients with minor stroke and TIA also had a high rate of asymptomatic lesions on repeat MRI scanning. Methods: Patients with minor stroke and TIA presenting within 12 hours of symptom onset with a NIH Stroke Scale score less than six, who had a baseline MRI and a 1-month follow-up, were enrolled in this study. The follow-up study was examined for new diffusion-weighted imaging lesions as compared to the baseline study. Clinical or MRI factors predicting recurrent lesions were examined. Results: A total of 143 patients were enrolled and 14 patients (9.8%; 95%CI 5.4, 15.9) had MR evidence of new lesions at 30 days. Six of these new lesions were clinically asymptomatic (42.9%; 95%CI 17.7, 71.1). A trend to increased likelihood of new lesions at 30 days was seen with progressing baseline scan lesion number (none [2.2%], solitary [12.9%], multiple [19.8%]: p = 0.046). Patients whose mechanism of stroke was large artery or cardioembolic were the most likely to have new lesions on follow-up MRI. Conclusion: Minor stroke and TIA are associated with a 10%risk of new lesions on MRI and half of these new lesions are asymptomatic. This risk is lower than seen in more severely affected patients with stroke. Patients with multiple lesions at baseline are at an increased risk for new ischemic lesions.展开更多
Background and Purpose -Transient ischemic attack (TIA) patients may deteriorate rapidly. MRI is being increasingly used to assess such patients. One possible mechanism of neurological worsening is the presence of per...Background and Purpose -Transient ischemic attack (TIA) patients may deteriorate rapidly. MRI is being increasingly used to assess such patients. One possible mechanism of neurological worsening is the presence of perfusion abnormalities. We sought to identify what proportion of TIA patients had evidence of perfusion abnormalities on MRI. Methods -TIA patients were prospectively enrolled and had a MRI completed as soon as possible. The images were assessed for the presence of perfusion abnormalities. Results -Sixty-nine TIA patients were enrolled, and 62 had perfusion imaging. In 56 patients (81%), the symptoms had resolved before imaging. In 21 patients (33.9%), there was evidence of a perfusion abnorm ality defined by relative mean transit time delay. In 12 patients (19.4%), the perfusion abnormality was present despite having complete resolution of neurological symptoms. We found no relationship between the presence of a perfusion abno rmality and the clinical outcome. Conclusions -A proportion of TIA patients have perfusion abnormalities evident on MRI.展开更多
文摘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 angiographysource 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. Methods - ASPECTS was assigned by 2 raters on the acute NCCT, CTA- SI, and follow- up imaging. The mean baseline ASPECTS of acute NCCT and CTA- SI was compared with the follow- up ASPECTS. Rate ratios (RRs) were used to quantify the relationship between the dichotomized baseline ASPECTS (categorized as 0 to 7 versus 8 to 10) and favorable patient outcome. Results - Thirty- nine patients were recruited. Proximal occlusion (internal carotid artery or middle cerebral artery) was seen in 62% , M2 occlusion in 18% , and no occlusion was seen in 20% of patients. The median time between symptom onset and imaging was 1.9 (1.2 to 2.5) hours. There was a significantly larger difference of 1.4 between the mean baseline NCCT and CTA- SI ASPECTS in patients who had more ischemic changes (follow up ASPECTS=0 to 3) than a difference of 0.6 in patients who had near- to- normal CT scans (follow- up ASPECTS=8 to 10). The rate of favorable outcome for acute NCCT ASPECTS of 8 to 10 was 51.8% versus 25.0% for 0 to 7 (RR, 2.1, 95% Cl: 0.7 to 5.9, P=0.12). For acute CTA- SI ASPECTS of 8 to 10, the rate of favorable outcome was 58.8% versus 31.8% for 0 to 7 (RR. 1.8, 95% CI: 0.9 to 3.8, P=0.09). Conclusions - CTA- SI ASPECTS provides added information in the prediction of final infarct size.
文摘Background: In a general population of patients with stroke, the rate of new MRI lesions at 1 week was much higher than expected. With patients with minor stroke and TIA having a higher risk of recurrent clinical events, the authors examined whether patients with minor stroke and TIA also had a high rate of asymptomatic lesions on repeat MRI scanning. Methods: Patients with minor stroke and TIA presenting within 12 hours of symptom onset with a NIH Stroke Scale score less than six, who had a baseline MRI and a 1-month follow-up, were enrolled in this study. The follow-up study was examined for new diffusion-weighted imaging lesions as compared to the baseline study. Clinical or MRI factors predicting recurrent lesions were examined. Results: A total of 143 patients were enrolled and 14 patients (9.8%; 95%CI 5.4, 15.9) had MR evidence of new lesions at 30 days. Six of these new lesions were clinically asymptomatic (42.9%; 95%CI 17.7, 71.1). A trend to increased likelihood of new lesions at 30 days was seen with progressing baseline scan lesion number (none [2.2%], solitary [12.9%], multiple [19.8%]: p = 0.046). Patients whose mechanism of stroke was large artery or cardioembolic were the most likely to have new lesions on follow-up MRI. Conclusion: Minor stroke and TIA are associated with a 10%risk of new lesions on MRI and half of these new lesions are asymptomatic. This risk is lower than seen in more severely affected patients with stroke. Patients with multiple lesions at baseline are at an increased risk for new ischemic lesions.
文摘Background and Purpose -Transient ischemic attack (TIA) patients may deteriorate rapidly. MRI is being increasingly used to assess such patients. One possible mechanism of neurological worsening is the presence of perfusion abnormalities. We sought to identify what proportion of TIA patients had evidence of perfusion abnormalities on MRI. Methods -TIA patients were prospectively enrolled and had a MRI completed as soon as possible. The images were assessed for the presence of perfusion abnormalities. Results -Sixty-nine TIA patients were enrolled, and 62 had perfusion imaging. In 56 patients (81%), the symptoms had resolved before imaging. In 21 patients (33.9%), there was evidence of a perfusion abnorm ality defined by relative mean transit time delay. In 12 patients (19.4%), the perfusion abnormality was present despite having complete resolution of neurological symptoms. We found no relationship between the presence of a perfusion abno rmality and the clinical outcome. Conclusions -A proportion of TIA patients have perfusion abnormalities evident on MRI.
