ABSTRACT
BACKGROUND: Limited research exists regarding the impact of neuroimaging on endovascular thrombectomy (EVT) decisions for late-window cases of large vessel occlusion (LVO) stroke. OBJECTIVE: T0 assess whether perfusion CT imaging: (1) alters the proportion of recommendations for EVT, and (2) enhances the reliability of EVT decision-making compared with non-contrast CT and CT angiography. METHODS: We conducted a survey using 30 patients drawn from an institutional database of 3144 acute stroke cases. These were presented to 29 Canadian physicians with and without perfusion imaging. We used non-overlapping 95% confidence intervals and difference in agreement classification as criteria to suggest a difference between the Gwet AC1 statistics (κG). RESULTS: The percentage of EVT recommendations differed by 1.1% with or without perfusion imaging. Individual decisions changed in 21.4% of cases (11.3% against EVT and 10.1% in favor). Inter-rater agreement (κG) among the 29 raters was similar between non-perfusion and perfusion CT neuroimaging (κG=0.487; 95% CI 0.327 to 0.647 and κG=0.552; 95% CI 0.430 to 0.675). The 95% CIs overlapped with moderate agreement in both. Intra-rater agreement exhibited overlapping 95% CIs for all 28 raters. κG was either substantial or excellent (0.81-1) for 71.4% (20/28) of raters in both groups. CONCLUSIONS: Despite the minimal difference in overall EVT recommendations with either neuroimaging protocol one in five decisions changed with perfusion imaging. Regarding agreement we found that the use of automated CT perfusion images does not significantly impact the reliability of EVT decisions for patients with late-window LVO.
ABSTRACT
BACKGROUND Focal seizure with impaired awareness, post-seizure Todd's phenomenon, and post-stroke recrudescence can all present with focal neurological deficits, mimicking stroke. As acute ischemic stroke mimics, they are distractors in the emergency setting where management is time-sensitive both for seizure and stroke. Nevertheless, a timely diagnosis can be made with exploration of the clinical features supported by investigation such as computerized tomographic perfusion. CASE REPORT Our patient was a 65-year-old woman who was known hypertensive, with type 2 diabetes mellitus, and previous intracerebral hemorrhage with minimal right-sided residual deficits, but still able to ambulate independently. She was brought to the Emergency Department because 1 hour prior to presentation, she had sudden worsening of weakness of the right limbs, aphasia, aggression, and confusion. An initial impression of repeat acute stroke, focal seizure with impaired awareness, Todd's phenomenon, and post-stroke recrudescence was considered. While CT angiography was suggestive of left middle cerebral artery occlusion, CT perfusion revealed extensive hypoperfusion patterns beyond the region of the occlusion, thus suggesting a different etiology from acute ischemic stroke. In view of her previous left hemispheric lesion coupled with the presentation, our working diagnosis was seizure with Todd's phenomenon, and she was started on an anti-epileptic drug. Her condition returned to baseline within 24 h of admission and was subsequently discharged. CONCLUSIONS Our case demonstrates that adequate elucidation of clinical features in conjunction with CT perfusion, as a dual-purpose tool, can aid the diagnosis of both stroke mimics and acute ischemic stroke in the Emergency Department where rapid treatment is essential.
