Automated ASPECTS Segmentation and Scoring Tool: a Method Tailored for a Colombian Telestroke Network.

To evaluate our two non-machine learning (non-ML)-based algorithmic approaches for detecting early ischemic infarcts on brain CT images of patients with acute ischemic stroke symptoms, tailored to our local population, to be incorporated in our telestroke software. One-hundred and thirteen acute stroke patients, excluding hemorrhagic, subacute, and chronic patients, with accessible brain CT images were divided into calibration and test sets. The gold standard was determined through consensus among three neuroradiologist. Four neuroradiologist independently reported Alberta Stroke Program Early CT Scores (ASPECTSs). ASPECTSs were also obtained using a commercial ML solution (CMLS), and our two methods, namely the Mean Hounsfield Unit (HU) relative difference (RELDIF) and the density distribution equivalence test (DDET), which used statistical analyze the of the HUs of each region and its contralateral side. Automated segmentation was perfect for cortical regions, while minimal adjustment was required for basal ganglia regions. For dichotomized-ASPECTSs (ASPECTS < 6) in the test set, the area under the receiver operating characteristic curve (AUC) was 0.85 for the DDET method, 0.84 for the RELDIF approach, 0.64 for the CMLS, and ranged from 0.71-0.89 for the neuroradiologist. The accuracy was 0.85 for the DDET method, 0.88 for the RELDIF approach, and was ranged from 0.83 - 0.96 for the neuroradiologist. Equivalence at a margin of 5% was documented among the DDET, RELDIF, and gold standard on mean ASPECTSs. Noninferiority tests of the AUC and accuracy of infarct detection revealed similarities between both DDET and RELDIF, and the CMLS, and with at least one neuroradiologist. The alignment of our methods with the evaluations of neuroradiologist and the CMLS indicates the potential of our methods to serve as supportive tools in clinical settings, facilitating prompt and accurate stroke diagnosis, especially in health care settings, such as Colombia, where neuroradiologist are limited.

A Chilean Experience of Telestroke in a COVID-19 Pandemic Year.

BACKGROUND AND PURPOSE: Telemedicine for stroke patients' care (telestroke [TS]) has grown notably in recent decades and may offer advantages during health crisis. Hospital admissions related to stroke have decreased globally during the COVID-19 pandemic, but scarce information is available regarding the effect of COVID-19 in TS. Using a population-based TS registry, we investigated the impact of the first year of the COVID-19 pandemic throughout our TS network in Santiago, Chile. METHODS: Stroke codes evaluated after the onset of COVID-19 restrictions in Chile (defined as March 15, 2020) were compared with those evaluated in 2019. We analyzed differences between number of stroke codes, thrombolysis rate, stroke severity, and time from the stroke onset to hospital admission. RESULTS: We observed that the number of stroke codes and the number of patients undergoing reperfusion therapy did not change significantly (p = 0.669 and 0.415, respectively). No differences were found with respect to the median time from the stroke onset to admission (p = 0.581) or in National Institutes of Health Stroke Scale (NIHSS) scores (p = 0.055). The decision-making-to-needle time was significantly shorter in the COVID-19 period (median 5 min [IQR 3-8], p < 0.016), but no significant changes were found at the other times. CONCLUSIONS: This study demonstrates the potential of adapting TS to extreme situations such as the COVID-19 pandemic, as well as the importance of establishing networks that facilitate patient access to quality treatments.

Reliability and accuracy of individual Alberta Stroke Program Early CT Score regions using a medical and a smartphone reading system in a telestroke network.

INTRODUCTION: The aim of this study was to assess individual regions of the Alberta Stroke Program Early CT Score in noncontrast head computed tomography interpretations using a smartphone in a telestroke network, by comparison to a medical monitor. METHODS: The review board of our institution approved this retrospective study. A factorial design with 188 patients, four radiologists and two reading systems was used. Accuracy and reliability were evaluated. RESULTS: Very good interobserver agreements were observed on the total Alberta Stroke Program Early CT Score for both the medical and smartphone reading systems, with intraclass correlation coefficients of 0.91 and 0.84 respectively. Interobserver agreements were moderate to very good for the medical reading system (all intraclass correlation coefficients >0.74), whereas they were fair to very good for the smartphone (intraclass correlation coefficients ranged from 0.31-0.81). All intraobserver agreements were good (intraclass correlation coefficient >0.64), except for internal capsule (0.48) and M2 (0.55) regions. The areas under the receiver-operating curve ranged from 0.69-0.89 for the medical system, while for the smartphone ranged from 0.44-0.86. No statistical differences were observed between medical and smartphone reading systems for each region (all p > 0.05). DISCUSSION: If radiologists are better trained in the evaluation of the lesions in the insula, the internal capsule and the M2 regions, the total and the dichotomised Alberta Stroke Program Early CT Score will be more precise. Hence, ruling out contraindications to thrombolysis administration will be improved, allowing assessment of head computed tomography in a telestroke network using a smartphone to be a common practice.

Comprehensive Telestroke Network to Optimize Health Care Delivery for Cerebrovascular Diseases: Algorithm Development.

BACKGROUND: Health care delivery for cerebrovascular diseases is a complex process, which may be improved using telestroke networks. OBJECTIVE: The purpose of this work was to establish and implement a protocol for the management of patients with acute stroke symptoms according to the available treatment alternatives at the initial point of care and the transfer possibilities. METHODS: The review board of our institutions approved this work. The protocol was based on the latest guidelines of the American Heart Association and American Stroke Association. Stroke care requires human and technological resources, which may differ according to the patient's point of entry into the health care system. Three health care settings were identified to define the appropriate protocols: primary health care setting, intermediate health care setting, and advanced health care setting. RESULTS: A user-friendly web-based telestroke solution was developed. The predictors, scales, and scores implemented in this system allowed the assessment of the vascular insult severity and neurological status of the patient. The total number of possible pathways implemented was as follows: 10 in the primary health care setting, 39 in the intermediate health care setting, and 1162 in the advanced health care setting. CONCLUSIONS: The developed comprehensive telestroke platform is the first stage in optimizing health care delivery for patients with stroke symptoms, regardless of the entry point into the emergency network, in both urban and rural regions. This system supports health care personnel by providing adequate inpatient stroke care and facilitating the prompt transfer of patients to a more appropriate health care setting if necessary, especially for patients with acute ischemic stroke within the therapeutic window who are candidates for reperfusion therapies, ultimately contributing to mitigating the mortality and morbidity associated with stroke.

Accuracy and Reliability of the Recommendation for IV Thrombolysis in Acute Ischemic Stroke Based on Interpretation of Head CT on a Smartphone or a Laptop.

OBJECTIVE. The objective of this study was to assess the accuracy and reliability of IV thrombolysis recommendations made after interpretation of head CT images of patients with symptoms of acute stroke displayed on smartphone or laptop reading systems compared with those made after interpretation of images displayed on a medical workstation monitor. MATERIALS AND METHODS. This retrospective study was institutional review board-approved, and the requirement for informed consent was waived. We used a factorial design including 2256 interpretations (188 patients, four neuroradiologists, and three reading systems). To evaluate the reliability, we calculated the intraobserver and interobserver agreements using the intraclass correlation coefficient (ICC) and the following interpretation variables: hemorrhagic lesions, intraaxial neoplasm, stroke dating (acute, subacute, and chronic), hyperdense arteries, and infarct size assessment. Accuracy equivalence tests were performed for the IV thrombolysis recommendation; for this variable, sensitivity, specificity, and ROC curves were evaluated. RESULTS. Good or very good interobserver and intraobserver agreements were obtained after interpretation of each variable. The IV thrombolysis recommendation showed very good interobserver agreements (ICC ≥ 0.85) and very good intraobserver agreements (ICC ≥ 0.81). For the IV thrombolysis recommendation, the AUC values (0.83-0.84) and sensitivities (0.94-0.95) were equivalent among all the reading systems at a 5% equivalent threshold. CONCLUSION. Our study found that mobile devices are reliable and accurate to help stroke teams to decide whether to administer IV thrombolysis in patients with acute stroke.

Evaluation of the Accuracy Equivalence of Head CT Interpretations in Acute Stroke Patients Using a Smartphone, a Laptop, or a Medical Workstation.

PURPOSE: To evaluate and compare the clinical performance of observers interpreting head CT images from patients with symptoms of acute stroke with a medical workstation or a smartphone or laptop reading system. MATERIALS AND METHODS: Our institutional review board approved this retrospective study and waived the requirement for informed consent. We employed a factorial design including 2,256 interpretations (188 patients × 4 neuroradiologists × 3 reading systems). Accuracy equivalence tests, at a threshold of 5% and 10%, were performed for the following variables: detection of imaging contraindications for intravenous recombinant tissue-type plasminogen activator administration (eg, hemorrhagic lesions), ischemic lesions, hyperdense arteries, and acute ischemic lesions. For each clinical variable, the sensitivity, specificity, and receiver operating characteristic (ROC) curves were evaluated. RESULTS: For each variable, the shapes of the ROC curves were very similar for all of the reading systems, indicating similar observer performance with different specificities and sensitivities. For all the clinical variables, the areas under the ROC curves were equivalent for all of the reading systems at a 10% threshold and were equivalent at a 5% threshold for hemorrhagic lesions, hyperdense middle cerebral artery, and acute ischemic lesion in the middle cerebral artery territory. There was no more than 30 seconds of difference between the reading time of the mobile devices compared with that for the medical workstation. CONCLUSION: The results of this pilot study showed equivalent diagnostic accuracy when using smartphone and laptops compared with medical monitors to interpret head CT images of patients with symptoms of acute stroke.

Women on Hormone Therapy with Ischemic Stroke, Effects on Deficits and Recovery.

BACKGROUND: Hormone replacement therapy (HT) for post-menopausal women is associated with increased incidence of ischemic stroke risk. Effects of HT on stroke related deficits and functional outcomes in acute ischemic stroke (AIS) are uncertain. We retrospectively examined female consult data for HT use and National Institutes of Health Stroke Score (NIHSS) at baseline and recovery for 2015 and 2016 in a large stroke telemedicine program. HYPOTHESIS: The age of women who acknowledged HT use will negatively impact stroke severity and outcomes. METHODS: We analyzed consult data from two consecutive years for all women and included HT use, current age, and baseline and 24 h NIHSS's. We included all women consults regardless of IV Alteplase treatment. 24 h NIHSS and three month modified Rankin scale (mRS) were included from women given IV Alteplase. RESULTS: Strokes were identified in 523 women and 244 women received Alteplase therapy. Women without HT use numbered 459 and 64 women listed HT use. Mean NIHSS scores regardless of HT use significantly improved 24 h NIHSS vs. baseline NIHSS (p<0.0001). Baseline NIHSS scores were significantly improved in women on HT vs. non-HT users (p=0.01) in women age 50 to 79 years. Although mean NIHSS scores at 24h was not different from HT to no HT use (4.9 ± 1.6 vs. 7.8 ± 0.6, p=0.08) a trend was present for lower NIHSS scores for women 50-79 years. The mRS scores at three months indicated significant improvements among HT users vs. non-HT use (1.46 ± 0.4 vs. 2.51 ± 0.2, p=0.05). CONCLUSION: While cautions persist on the use, route and dosage of HT for risks of ischemic stroke, the HT moderation of AIS deficits and outcomes in women <80 years of age warrants further investigation.

Impact of simulation training on a telestroke network.

BACKGROUND: Stroke is a leading cause of morbidity and mortality in Brazil, where there are significant imbalances in access to specialized stroke care. Telemedicine networks allow patients to receive neurological evaluation and intravenous thrombolysis in underserved areas, where performance measures are challenging. AIMS: To describe the impact caused by adequate stroke care training, using realistic simulation, in a developing country telestroke network. METHODS: Retrospective observational study comparing the number of all stroke diagnoses, thrombolysis rate, door-to-needle time and symptomatic intracranial hemorrhage after intravenous thrombolysis, during one year providing just algorithms and orientation in stroke care to spoke facilities (phase 1), with the results achieved along one year after the beginning of ongoing live training sessions (phase 2). RESULTS: The mean number of patients diagnosed with stroke increased from 7.5 to 16.58 per month (P = 0.019) rising from 90 patients during phase 1 to 199 in phase 2. There was a reduction in the mean door-to-needle time from 137.1 to 95.5 min (-41.58; 95% CI -62.77 to -20.40). The thrombolysis and symptomatic intracranial hemorrhage rates had a non-significant decrease from 21.31% to 18.18% (OR 0.82; 95% CI 0.39 to 1.71) and 12.5% to 7.69% (OR 0.58; 95% CI 0.046 to 7.425), respectively. CONCLUSIONS: Realistic simulation stroke care training provided by stroke centers to spoke facilities seems to significantly reduce door-to-needle time and enhance adherence in a telestroke network.

Telestroke Imaging: A Review.

The use of telecommunications technology to provide the healthcare services, telemedicine, has been in use since the 1860s. The use of technology has ranged from providing medical care to far-off places during wartimes to monitoring physiological measurements of astronauts in space. Since the 1990s, reports have been published on diagnoses of neurological diseases with the use of video links. Studies confirm that the neurological examinations, including the National Institutes of Health Stroke Scale, performed during teleneurology are dependable. The transfer of stroke patients in rural hospitals to bigger medical centers delays treatment while there exists current and projected shortage of neurologists. Telestroke provides the solution. Patients suspected of acute stroke need a noncontrast computerized tomography (CT) scan for tissue plasminogen activator administration. Vascular imaging such as CT angiography, magnetic resonance angiography, and digital subtraction angiography can help show large-vessel occlusion or critical stenosis responsive to endovascular therapy. A standard protocol can be followed to decide a vascular modality of choice, considering advantages and disadvantages of each imaging modality. Telestroke solves the problems of distance and of shortage of neurologists. Neuroimaging plays a vital role in the delivery of telestroke, and the telestroke doctor should be comfortable with making a decision on selecting an appropriate vascular imaging modality.