Application Value of Intelligent Quick Magnetic Resonance in Accelerating Brain MR Scanning Speed and Improving Image Quality for Acute Ischemic Stroke.

Introduction: Alberta Stroke Program Early CT Score (ASPECTS) is a validated clinical tool to predict early ischemic changes in acute ischemic stroke (AIS). In addition to scoring of non-contrast brain CT images (CT), head CT angiogram source images (CTA) have also been demonstrated as useful for scoring. We hypothesized that CTA ASPECTS would show superior inter-rater reliability as compared to CT ASPECTS, and that both would perform better in the setting of the favorable target mismatch (TM) profile on CT perfusion imaging (CTP). Methods: We reviewed AIS patients from 2010-2014 with an acute M1 middle cerebral artery occlusion that underwent CT, CTA, and CTP imaging at hospital admission. CT and CTA were independently scored by two experienced physician raters using the standard ASPECTS methodology. Inter-rater agreement was calculated with a weighted kappa. The cohort was then further stratified into either favorable or non-favorable TM profiles using volumetric measurements from the Olea Sphere software and the DEFUSE-3 definition of TM. Results: We included 68 patients. The mean±SD age was 62±18 years. 60% were men. The mean NIH stroke scale was 14.5±7.9. The median (IQR) follow-up modified Rankin Scale (mRS) was 3 (1,6). 37 of 68 (54%) patients had the TM profile and were significantly more likely to have lower follow-up mRS scores (z=3.5, p<0.001). Inter-rater agreement of CTA ASPECTS (kappa=0.82) was superior to CT ASPECTS (kappa=0.76). Patients with the TM profile demonstrated more reliable agreement on both CTA and CT ASPECTS scoring systems (kappa=0.79, 0.78), compared to those without the TM profile (kappa=0.71, 0.75). Discussion: We found that inter-rater agreement was higher for CTA ASPECTS as compared to CT ASPECTS and that both performed better in patents with the TM profile. Clinically this is important because it reaffirms the utility of CTA ASPECTS in this population of patients in which high reliability is paramount, as ASPECTS is often used in medical decision making when determining eligibility for medical and/or endovascular thrombolytic therapies.

Introduction: We aimed to investigate the outcome of endovascular treatment (EVT) for acute ischemic stroke in patients with low Alberta Stroke Program Early CT Score (ASPECTS). Methods: This study reports on MR CLEAN Registry patients with available baseline ASPECTS (N=1423). ASPECTS was trichotomized in 0-4, 5, and 6-10 in order to create low ASPECTS groups of similar size. Primary outcome was modified Rankin Scale score (mRS) at 90 days. Secondary outcomes were symptomatic intracranial hemorrhage (sICH) and mortality. Benefit of reperfusion (defined as extended thrombolysis in cerebral infarction [eTICI] score 2B-3) was assessed by multivariable ordinal logistic regression analysis, including an interaction term of reperfusion and ASPECTS, and it was expressed as an adjusted common odds ratio (acOR). A comparison with the MR CLEAN trial control arm was made to assess benefit of EVT. Results: Higher trichotomized ASPECTS was associated with improved mRS (acOR 1.4, 95%CI 1.2-1.7). For ASPECTS 0-4 (n=93) successful reperfusion was not associated with improved mRS (acOR 1.4, 95%CI 0.6-2.9). ASPECTS 5 (n=63) and ASPECTS 6-10 subgroups (n=1267) however, did show significant benefit of reperfusion (acOR 3.9, 95%CI 1.3-11.8; acOR 2.7, 95%CI 2.2-3.3, respectively)(Fig1). Interaction between trichotomized ASPECTS and reperfusion was not significant ( p =0.13). Comparison with the MR CLEAN trial control group showed that trichotomized ASPECTS did not modify the effect of EVT ( p =0.14). Patients with lower trichotomized ASPECTS had a higher risk of mortality (aOR 0.9, 95%CI 0.9-1.0), but not of sICH (aOR 1.0, 95%CI 0.9-1.1). Conclusion: ASPECTS does not modify effect of reperfusion or EVT on functional outcome after acute ischemic stroke. Patients with ASPECTS 5 or higher seem to benefit from successful reperfusion.

Introduction: The Alberta Stroke Program Early CT Score (ASPECTS) is often used in considering whether patients are appropriate for thrombolysis and/or thrombectomy after acute ischemic stroke (AIS). We hypothesized that while clinical guidelines recommend ASPECTS evaluations in AIS, ASPECTS use is low in practice. We also explored differences in ASPECTS use between high and low volume comprehensive stroke centers (CSC). Methods: We surveyed United States CSC from 2021-2022 regarding ASPECTS utilization in evaluating eligibility for thrombolysis and/or thrombectomy in patients with suspected or confirmed large vessel occlusion. We asked whether ASPECTS was routinely used, if it was the preferred primary modality for final decision making, and whether an ASPECTS < 6 excluded a patient from thrombectomy consideration. Survey responses were divided between large (Annual volumes of ischemic strokes >600) and small CSC ( < 600). Chi square analysis was performed on this data. Results: Thirty-nine CSC completed the survey. Of these, 21 were large CSC and 18 were small CSC. Of all CSC, 31% did not use ASPECTS at all. Seventy-four percent preferred automated mismatch software over ASPECTS as the primary modality in final decision making. Thirty six percent of CSC noted that an ASPECTS < 6 would exclude a patient from consideration for thrombectomy. There was no relationship between CSC size and ASPECTS use [X 2 (1, N = 39) = 0.71, p < .05]. There was also no relationship between CSC size and whether ASPECTS was the preferred primary final decision making modality [X 2 (1, N = 39) = 0.23, p < .05]. Additionally, there was no relationship between CSC size and whether ASPECTS < 6 excluded patients from thrombectomy consideration [X 2 (1, N = 39) = 0.73, p < .05]. Conclusion: In practice, the clinical utility of ASPECTS for AIS evaluation is low. Case volume experience also has no apparent impact on ASPECTS utilization. Our preliminary survey reveals low use of ASPECTS, and a preference for mismatch software in choosing AIS candidates for intervention. This discrepancy suggests significant differences between clinical guidelines and actual practice.

Stroke-associated pneumonia (SAP) is a serious complication in stroke patients, significantly increasing mortality. The Alberta Stroke Program Early CT Score (ASPECTS) is a recognized predictor of acute ischemic stroke outcomes. We aimed to investigate the performance of serial ASPECTS assessments (baseline ASPECTS, 24-h ASPECTS, and change in ASPECTS) for predicting SAP in patients with thrombolyzed acute anterior circulation ischemic stroke (AACIS). A retrospective observational cohort study of adult patients with thrombolyzed AACIS was conducted. Baseline and 24-h ASPECTS using non-contrast computed tomography (NCCT), complications of stroke, including SAP and swallowing dysfunction using the Modified Water Swallowing test, were collected. Baseline and 24-h ASPECTS were evaluated by a certified neurologist and neuroradiologist. The predictive performance was determined based on the receiver operating characteristic curve (ROC). Multivariable logistic regression analyses were employed to assess the impact of serial ASPECTS assessment on predicting SAP. Of the 345 patients with thrombolyzed AACIS in our study, 18.4% (64/345) experienced SAP. The patients' median age was 62 years [interquartile range (IQR): 52-73], with 53.4% being male. The median NIHSS score was 11 points (IQR: 8-17). The ROC analysis revealed areas under the curve for predicting SAP with baseline ASPECTS, 24-h ASPECTS, and change in ASPECTS were 0.75 (95% CI, 0.69-0.82), 0.84 (95% CI, 0.79-0.89), and 0.82 (95% CI, 0.76-0.87), respectively. Of the three measures, 24-h ASPECTS was a better predictor of SAP (odds ratio: 5.33, 95%CI: 2.08-13.67, p < 0.001) and had a higher sensitivity (0.84 [95%CI, 0.74-0.92]) and specificity (0.79 [95%CI, 0.74-0.84]) than both baseline ASPECTS and change in ASPECTS. 24-h NCCT-ASPECTS outperformed both baseline ASPECTS and change in ASPECTS for predicting SAP. Notably, 24-h ASPECTS, with a cut-off value of ≤6, exhibited good predictive performance and emerged as the better predictor for SAP.

Objective: The Alberta Stroke Program Early CT Score (ASPECTS) method has been widely used to assess non-contrast CT scans from acute ischemic stroke (AIS) patients. Although the ASPECTS is a simple and systematic approach, ASPECTS scoring accuracy and reliability is still a challenge to clinicians, especially with limited experience. The objective of this study is to develop an automated ASPECTS scoring method, which could provide objective assessment and decision-making support. Methods: We collected 160 AIS patient NCCT images with thickness of 5mm (&lt;8 hours from onset to scans) followed by DWI acquisition within 1 hour of NCCT. Expert ASPECTS readings on DWI with 20% thresholding (20% of a given ASPECTS region showed diffusion restriction to be scored as affected) were used as ground truth for evaluations. A NCCT template with ASPECTS regions manually contoured was non-linearly registered onto all NCCT images and ASPECTS regions were then automatically mapped onto subject NCCT images. Image features extracted from each ASPECTS region, such as regional intensity profile, neighbor context, and texture information, were used to train a random forest classifier to discriminate whether an ASPECTS region has ischemic changes. Leave-one-out validation was performed to evaluate the trained model against expert readings on DWI. Results: The proposed method generated an individual ASPECTS region level detection accuracy of 85.3% and only a 1-point discrepancy in total ASPECTS scores compared to expert reading on MRI. Bland-Altman plot of automated ASPECTS vs. expert MRI ASPECTS shows good agreement (Figure 1). The automated ASPECTS method has very high agreement (91.3%) and specificity (98.5%) when dichotomized (ASPECTS 0-4 vs. 5-10). Conclusions: The automated ASPECTS scoring approach is reliable and accurate and can potentially be used to make decisions in patients with acute ischemic stroke.

Background: ASPECTS was developed for the semi-quantitative assessment of early ischemic changes (EIC) on non-contrast computed tomography (NCCT) in acute ischemic stroke (AIS). Artificial intelligence (AI)-based automated tools for the ASPECT scoring system were developed to automate the diagnosis and improve the agreement with radiologists of AIS. The performance of the automated software compared to physicians should be tested before the software is further used in clinical practice as a tool for clinicians. Objective: To evaluate the agreement with radiologists of an AI-based automated post-processing software for detecting EIC and calculating ASPECTS on NCCT images in AIS patients using a radiologist's assessment as a reference. Materials and Methods: NCCT of AIS patients were retrospectively reviewed (Stroke Fast Track Service July 2022 - December 2023). The complete set of clinical data and imaging data from both baseline and follow-up were analyzed by a radiologist as a reference. Two additional observers provided individual ASPECTS from the baseline NCCT only (observer 1 was a radiologist who independently reviewed only the baseline NCCT with stroke window setting. Observer 2 was a radiologist on service which was from the pool of 20 radiologists onsite and online). Recon&amp;GO Inline ASPECTS software (Somaris X, VA40A, Siemens Healthineers AG, Erlangen, Germany) was applied. Both ASPECT score analysis and ASPECTS region analysis were evaluated. Positive percent agreement (PPA) and negative percent agreement (NPA) were calculated. Interobserver agreement was assessed using the Cohen's kappa coefficient and the intraclass correlation coefficient (ICC). Results: 111 patients with a mean age of 67.8 years (±11.9), 56 (50.5%) females, a mean National Institute of Health Stroke Scale (NIHSS) score of 14.2 (±8.8), and a mean time to baseline NCCT of 123.9 minutes (±58.7) were included. For dichotomized ASPECTS, the automated software showed lower PPA (14.6% vs. 27.1%) but higher NPA (100.0% vs. 93.7%) than observer 2. For the region-based analysis, both the automated software and observer 2 differed in terms of regional contribution. The automated software showed low PPA but rather high NPA with perfect (100%) NPA in lentiform nucleus and M2. The automated software showed higher agreement with the reference and two observers in deep/central regions than cortical regions. For total ASPECTS, the automated software showed a moderate agreement of total ASPECTS with the reference and observer 1 (ICC = 0.545 and 0.545). Observer 2 showed a poor agreement of total ASPECTS with the reference, observer 1, and the automated software (ICC = 0.349, 0.422, and 0.301, respectively). Conclusion: For total ASPECT score, the agreement of the tested AI software is lower compared to observer 1 obtained by a radiologist using the stroke window on NCCT, but better compared to a pool of radiologists on service with a time limit of 30 minutes to interpret the ASPECT score. When analyzing the ASPECTS regions, there are different advantages for the assessment of the deep regions and the cortical regions. The tested AI software shows higher agreement in deep/central regions than cortical regions. From the result, the tested AI software retains its potential for use in emergency situations, particularly for radiologists with limited experience and limited time to report.

Response

The Alberta Stroke Program Early CT Score (ASPECTS) scale was developed for monitoring early ischemic changes on CT, being associated with clinical outcomes. The ASPECTS can also associate with peripheral biomarkers that reflect the pathophysiological response of the brain to the ischemic stroke. To investigate the association between peripheral biomarkers with the Alberta Stroke Program Early CT Score (ASPECTS) in individuals after ischemic stroke. Patients over 18 years old with acute ischemic stroke were enrolled in this study. No patient was eligible for thrombolysis. The patients were submitted to non-contrast CT in the first 24 hours of admission, being the Alberta Stroke Program Early CT Score and clinical and molecular evaluations applied on the same day. The National Institutes of Health Stroke Scale (NIHSS), modified Rankin scale and the Mini-Mental State Examination for clinical evaluation were also applied to all subjects. Plasma levels of BDNF, VCAM-1, VEGF, IL-1β, sTNFRs and adiponectin were determined by ELISA. Worse neurological impairment (NIHSS), cognitive (MEEM) and functional (Rankin) performance was observed in the group with changes in the NCTT. Patients with NCTT changes also exhibited higher levels of IL-1β and adiponectin. In the linear multivariate regression, an adjusted R coefficient of 0.515 was found, indicating adiponectin and NIHSS as independent predictors of ASPECTS. Plasma levels of adiponectin are associated with the ASPECTS scores.

Alberta Stroke Program Early CT Score (ASPECTS) was devised as a systematic method to assess the extent of early ischemic change on noncontrast CT (NCCT) in patients with acute ischemic stroke (AIS). Our aim was to automate ASPECTS to objectively score NCCT of AIS patients. We collected NCCT images with a 5-mm thickness of 257 patients with acute ischemic stroke (<8 hours from onset to scans) followed by a diffusion-weighted imaging acquisition within 1 hour. Expert ASPECTS readings on DWI were used as ground truth. Texture features were extracted from each ASPECTS region of the 157 training patient images to train a random forest classifier. The unseen 100 testing patient images were used to evaluate the performance of the trained classifier. Statistical analyses on the total ASPECTS and region-level ASPECTS were conducted. For the total ASPECTS of the unseen 100 patients, the intraclass correlation coefficient between the automated ASPECTS method and DWI ASPECTS scores of expert readings was 0.76 (95% confidence interval, 0.67-0.83) and the mean ASPECTS difference in the Bland-Altman plot was 0.3 (limits of agreement, -3.3, 2.6). Individual ASPECTS region-level analysis showed that our method yielded κ = 0.60, sensitivity of 66.2%, specificity of 91.8%, and area under curve of 0.79 for 100 × 10 ASPECTS regions. Additionally, when ASPECTS was dichotomized (>4 and ≤4), κ = 0.78, sensitivity of 97.8%, specificity of 80%, and area under the curve of 0.89 were generated between the proposed method and expert readings on DWI. The proposed automated ASPECTS scoring approach shows reasonable ability to determine ASPECTS on NCCT images in patients presenting with acute ischemic stroke.

Background and purpose: The Alberta stroke program early computed tomography score (ASPECTS) on baseline imaging is known predictor of outcomes for acute ischemic stroke (AIS) patients. We looked at the change in ASPECTS at the baseline CT and 24hr CT in AIS patients treated with IV rTPA to determine if it can help predict 3 month functional outcomes. Methods: Consecutive AIS patients receiving IV-tPA within 4.5 hours of symptom-onset during 2010-2013 and underwent pre-treatment and day-2 CT were included ASPECTS at the baseline CT and 24hr CT were independently scored in all anterior circulation stroke patients who underwent IV rTPA within 4.5 hours of onset. ASPECTS at baseline, 24hrs and the serial change were analyzed. Results: 210 consecutive AIS patients were included. ROC curves for ASPECTS on the initial CT scan for MRS 0-1 was AUC 0.613, 95% CI 0.536-0.690, p=0.005, while ROC curves for ASPECTS on the 24hr CT scan for MRS0-1 was AUC 0.763 95% CI 0.699 - 0.828, p &lt;0.001. ASPECTS on the 24hr CT was statistically significantly better able to predict outcomes compared to the initial CT (z= -2.936, p = 0.001). 28 out of 210 patients had an increase in ASPECTS by &gt;3 with a 3-fold risk of worse outcomes (OR 3.572 95%CI 1.393- 9.156, p=0.08). Conclusion: ASPECT scores on 24hr CT have better prognostic ability compared to the baseline scan. Serial ASPECT scores are a viable surrogate predictor in AIS patients treated with IV rTPA.

Validation of Serial Alberta Stroke Program Early CT Score as an Outcome Predictor in Thrombolyzed Stroke Patients

Post-stroke spasticity is common and an early predictor of the severity of spasticity can help track recovery trajectory helping to modify rehabilitation plans. We explored the utility of the Alberta Stroke Program Early CT Score (ASPECTS) to predict functional motor capacity in patients after acute ischemic stroke. One hundred and one patients (mean age of 58.6 ± 7.6 years; M:F = 72: 29) with the first documented acute ischemic stroke were followed up for three to twelve months after the stroke. Cerebral lesions within the territory of the middle cerebral artery were evaluated using the ASPECTS. Spasticity was assessed using the Modified Ashworth Score (MAS) and walking with Timed Up and Go test (TUG). The associations between severity of spasticity and size/extent of infarct as derived from ASPECTS and between spasticity and functional walking in post-stroke survivors were analyzed. Among the patients studied, 61.3% (n = 62) had infarct in the region of supply of the left middle cerebral artery (MCA) and 38.7% (n = 39) had infarct in the region supplied by the right MCA. Three percent (n = 3) had a low ASPECTS, 53.6% (n = 54) had an intermediate score and 44.4% (n = 44) had a high score. The majority of patients with no to mild spasticity had high ASPECTS. Worse spasticity was significantly associated with low ASPECTS (P = 0.001). High scores in Timed Up and Go test (TUG) were associated with low ASPECTS (P < 0.001). Patients with high ASPECTS had the propensity to have subcortical infarcts (P < 0.001) when compared to those with moderate ASPECTS, who had a mix of cortical and subcortical infarcts. ASPECTS at admission in patients with acute ischemic stroke is a good predictor of post-stroke spasticity and functional walking. Low ASPECTS is associated with higher spasticity and lower functional walking status on follow-up after stroke.

<h3>BACKGROUND AND PURPOSE:</h3> Alberta Stroke Program Early CT Score (ASPECTS) was devised as a systematic method to assess the extent of early ischemic change on noncontrast CT (NCCT) in patients...

Evaluation of combining Alberta Stroke Program Early CT Score (ASPECTS) with mean platelet volume, plateletcrit, and platelet count in predicting short- and long-term prognosis of patients with acute ischemic stroke

Objective: The Alberta Stroke Program Early CT Score (ASPECTS) is widely used to assess and diagnose acute ischemic stroke (AIS) patients. However, reliability of ASPECTS scoring is poor among physicians with limited expertise. We hypothesize that reliability for ASPECTS scoring can be improved by using algorithm enhanced gray-white matter (AEGWM) NCCT. Methods: Inter-rater reliability for ASPECTS scoring was assessed between plain and AEGWM NCCT by an expert and a novice reader. 50 AIS patient NCCT images were acquired acutely. NCCT images were then enhanced by skull stripping, image smoothing, histogram equalization, and JET color mapping. ASPECTS scoring was done on AEGWM color mapped NCCT and on standard 5mm NCCT images by a novice reader. ASPECTS scoring was done two days apart on standard NCCT first, followed by AEGWM NCCT. Expert (neuro-radiologist) scores on standard NCCT were then compared with scores from the novice reader on both regular and AEGWM NCCT. Results: Agreement between novice and expert for trichotomized ASPECTS (0-4, 5-7, 8-10) was best when the novice was reading ASPECTS on AEGWM NCCT (kappa=0.7093) vs. when novice read ASPECTS on standard NCCT (kappa=0.2409). Difference in scoring the full 10-point ASPECTS score was least when the novice read ASPECTS on AEGWM NCCT (mean ASPECTS difference between novice and expert for algorithm-enhanced NCCT 0.68 ± 1.1 vs. 1.48 ± 1.8 for standard NCCT). A Bland Altman plot comparing the difference is attached and the coefficient of variation was found to be 0.14 for AEGWM NCCT scoring. Conclusion: Algorithm Enhanced Gray-White Matter NCCT allows more accurate/ reliable ASPECTS scoring. Further evaluation on a larger dataset with readers with different levels of expertise is ongoing.