G. Ntaios and V. Papavasileiou have contributed equally and are co-first authors.
Acute imaging does not improve ASTRAL score's accuracy despite having a prognostic value
Article first published online: 3 JUN 2014
© 2014 World Stroke Organization
International Journal of Stroke
Volume 9, Issue 7, pages 926–931, October 2014
How to Cite
Ntaios, G., Papavasileiou, V., Faouzi, M., Vanacker, P., Wintermark, M. and Michel, P. (2014), Acute imaging does not improve ASTRAL score's accuracy despite having a prognostic value. International Journal of Stroke, 9: 926–931. doi: 10.1111/ijs.12304
Funding: Dr P. Michel has received through his employer (CHUV) research grants from the Swiss National Science Foundation, the Swiss Heart Foundation, and Cardiomet-CHUV for analyses based on the ASTRAL registry. The other co-authors report no disclosure.
Authors' contributions: G. Ntaios: Study concept and design, analysis and interpretation, preparation of the manuscript, study supervision. V. Papavasileiou: Data acquisition, analysis and interpretation, critical revision of the manuscript for important intellectual content. M. Faouzi: Analysis and interpretation, critical revision of the manuscript for important intellectual content. P. Vanacker: Data acquisition, critical revision of the manuscript for important intellectual content. M. Wintermark: Study concept and design, critical revision of the manuscript for important intellectual content. P. Michel: Study concept and design, data acquisition, analysis and interpretation, critical revision of the manuscript for important intellectual content, study supervision.
- Issue published online: 18 SEP 2014
- Article first published online: 3 JUN 2014
- Manuscript Accepted: 29 APR 2014
- Manuscript Received: 30 JAN 2014
- Swiss National Science Foundation
- Swiss Heart Foundation
- Cardiomet-CHUV for analyses based on the ASTRAL registry
- ASTRAL score;
- CT angiography;
- functional outcome;
- multimodal imaging;
- perfusion CT
The ASTRAL score was recently shown to reliably predict three-month functional outcome in patients with acute ischemic stroke.
The study aims to investigate whether information from multimodal imaging increases ASTRAL score's accuracy.
All patients registered in the ASTRAL registry until March 2011 were included. In multivariate logistic-regression analyses, we added covariates derived from parenchymal, vascular, and perfusion imaging to the 6-parameter model of the ASTRAL score. If a specific imaging covariate remained an independent predictor of three-month modified Rankin score > 2, the area-under-the-curve (AUC) of this new model was calculated and compared with ASTRAL score's AUC. We also performed similar logistic regression analyses in arbitrarily chosen patient subgroups.
When added to the ASTRAL score, the following covariates on admission computed tomography/magnetic resonance imaging-based multimodal imaging were not significant predictors of outcome: any stroke-related acute lesion, any nonstroke-related lesions, chronic/subacute stroke, leukoaraiosis, significant arterial pathology in ischemic territory on computed tomography angiography/magnetic resonance angiography/Doppler, significant intracranial arterial pathology in ischemic territory, and focal hypoperfusion on perfusion-computed tomography. The Alberta Stroke Program Early CT score on plain imaging and any significant extracranial arterial pathology on computed tomography angiography/magnetic resonance angiography/Doppler were independent predictors of outcome (odds ratio: 0·93, 95% CI: 0·87–0·99 and odds ratio: 1·49, 95% CI: 1·08–2·05, respectively) but did not increase ASTRAL score's AUC (0·849 vs. 0·850, and 0·8563 vs. 0·8564, respectively). In exploratory analyses in subgroups of different prognosis, age or stroke severity, no covariate was found to increase ASTRAL score's AUC, either.
The addition of information derived from multimodal imaging does not increase ASTRAL score's accuracy to predict functional outcome despite having an independent prognostic value. More selected radiological parameters applied in specific subgroups of stroke patients may add prognostic value of multimodal imaging.