, Volume 54, Issue 7, pp 663–672 | Cite as

The clot burden score, the Boston Acute Stroke Imaging Scale, the cerebral blood volume ASPECTS, and two novel imaging parameters in the prediction of clinical outcome of ischemic stroke patients receiving intravenous thrombolytic therapy

  • Niko SillanpaaEmail author
  • Jukka T. Saarinen
  • Harri Rusanen
  • Jari Hakomaki
  • Arto Lahteela
  • Heikki Numminen
  • Irina Elovaara
  • Prasun Dastidar
  • Seppo Soimakallio
Diagnostic Neuroradiology



Recently two classification methods based on the location and the extent of thrombosis detected with CT angiography have been introduced: the Boston Acute Stroke Imaging Scale (BASIS) and the clot burden score (CBS). We studied the performance of BASIS and CBS in predicting good clinical outcome (mRS ≤2 at 90 days) in an acute (<3 h) stroke cohort treated with intravenous thrombolytic therapy.


Eighty-three consecutive patients who underwent multimodal CT were analyzed. Binary logistic regression model was used to assess how BASIS, CBS, and cerebral blood volume (CBV) ASPECTS predict favorable clinical outcome. Diagnostic sensitivities and specificities were calculated and compared.


Patients with low CBS and CBV ASPECTS scores and major strokes according to BASIS had significantly higher admission NIHSS scores, larger perfusion defects, and more often poor clinical outcome. In logistic regression analysis, CBV ASPECTS, CBS and BASIS were significantly associated with the clinical outcome. The performance of BASIS improved when patients with thrombosis of the M2 segment of the middle cerebral artery were classified as having minor stroke (M1-BASIS). In the anterior circulation, the sum of CBS and CBV ASPECTS (CBSV) proved to be the most robust predictor of favorable outcome. CBV ASPECTS and CBS had high sensitivity but moderate to poor specificity while BASIS was only moderately sensitive and specific.


CBS, BASIS, and CBV ASPECTS are statistically robust and sensitive but unspecific predictors of good clinical outcome. Two new derived imaging parameters, CBSV and M1-BASIS, share these properties and may have increased prognostic value.


Boston Acute Stroke Imaging Scale Clot burden score Computed tomography perfusion Stroke ASPECTS 



Alberta Stroke Program Early CT Score


Area under the curve


Boston Acute Stroke Imaging Scale


Cerebral blood volume


C statistic


Clot burden score


Confidence interval


Computed tomography angiography


Computed tomography perfusion




Mean transit time


Middle cerebral artery


Noncontrast-enhanced computed tomography


National Institutes of Health Stroke Scale


Modified Rankin scale


Receiver operating characteristic


Recombinant tissue plasminogen activator



This work was supported by the Pirkanmaa Hospital District General Medical Research Fund.

Conflict of interest

We declare that we have no conflict of interest.


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Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  • Niko Sillanpaa
    • 1
    Email author
  • Jukka T. Saarinen
    • 2
  • Harri Rusanen
    • 3
  • Jari Hakomaki
    • 1
  • Arto Lahteela
    • 1
  • Heikki Numminen
    • 2
  • Irina Elovaara
    • 2
  • Prasun Dastidar
    • 1
  • Seppo Soimakallio
    • 1
  1. 1.Medical Imaging CenterTampere University HospitalTampereFinland
  2. 2.Department of NeurologyTampere University HospitalTampereFinland
  3. 3.Department of NeurologyOulu University HospitalOuluFinland

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