Computed tomography (CT) plays a pivotal role in the diagnosis of acute stroke and in treatment decision making. CT perfusion imaging performed with intravenous iodinated contrast material allows calculation of the time to peak enhancement, mean transit time, and cerebral blood volume, important parameters for differentiating between an ischemic penumbra, which might benefit from intravascular therapy with thrombolytic agents, and infarcted tissue, which would not benefit from such therapy. Differentiation between the two entities is important because thrombolytic therapy is associated with an increased risk for intracranial hemorrhage. A finding of delay in peak enhancement or increased mean transit time in a region with normal or only slightly abnormal cerebral blood volume is suggestive of an ischemic penumbra; however, accurate interpretation of the CT perfusion parameters may be difficult in the presence of a cerebrovascular anatomic variant or physiologic condition that produces benign oligemia leading to a false appearance of penumbra. For this reason, CT perfusion parameters must be correlated with the clinical history and findings at unenhanced head CT, angiography or CT angiography, and diffusion-weighted magnetic resonance imaging. The authors identify five possible causes of false penumbras, each of which produces a different pattern at imaging: upstream flow restriction, evolution of ischemic change, vascular dysregulation, positioning of the patient's head at an angle during image acquisition, and variant anatomy in the circle of Willis. Familiarity with the imaging patterns and causes of false penumbras may increase the radiologist's confidence in diagnosis and help avoid costly errors in treatment.

This study examined the initial learning trajectories of 13 upper elementary teachers as they developed technological, pedagogical, and content knowledge (TPACK) while participating in a 7-month professional development program focused on integrating technology into their classroom practice. The program was collaborative and non-prescriptive: teachers worked on self-chosen summer projects with flexible support from a university-based partner. A descriptive multicase study design was employed to track teachers' learning progressions. Data included interviews, surveys, digital artifacts, and researchers' notes and memos. During the program, teachers developed varying degrees of TPACK. Analyses distilled six initial TPACK learning trajectories.

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AIM: The purpose of this study was to explore the perceived value of certification among those with a neuroscience or stroke nursing certification. METHODS: The Perceived Value of Certification Tool-12 (PVCT-12) consists of 12 value statements related to the benefits of certification, using a 4-point Likert scale ranging from strongly disagree to strongly agree. Descriptive statistics were used to determine the percentage of agreement among respondents with each of the PVCT-12 items. A generalized linear model approach was then used to estimate the associations between age, sex, race, experience, certification, highest degree earned, primary responsibility, and primary work setting with intrinsic and extrinsic values. An exploratory factor analysis was performed to identify factors on which related variables were found. RESULTS: The 632 certificants were predominantly female (90%) with a mean age of 54 years. Approximately 80% were White, followed by Asian (11%), Hispanic (4%), and Black (3%). Certification included certified neuroscience registered nurse (34%), stroke certified registered nurse (47%), or both (20%). Approximately 57% of the certificants work in critical care/medical-surgical units. Work setting included academic (46%) and community (42%). Responses indicated lower levels of agreement with the value statements regarding certification challenges, professional autonomy, being listened to, and monetary gain. Those in administration had statistically significant higher intrinsic and extrinsic value scores (P = .005) as compared with those in nonadministrative roles. There was no significant difference on perceived intrinsic or extrinsic values for those who work in an academic environment versus those who work in a community environment (P = .25). After factor analysis, the PVCT-12 was found to have 3 factors that accounted for 53.4% of the total variation in the data: recognition of specialization, personal achievement, and professional accomplishment. CONCLUSION: The PVCT-12 incorporated a Likert-type scale to provide levels of agreement for intrinsic and extrinsic values among stroke certified registered nurses and certified neuroscience registered nurses. To complement these findings, further research using open-ended questions is needed to improve our understanding of participant responses regarding complex values such as “autonomy” and the “extent of being listened to.”