Neuroradiology

, Volume 54, Issue 7, pp 663–672

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

Authors

    • Medical Imaging CenterTampere University Hospital
  • Jukka T. Saarinen
    • Department of NeurologyTampere University Hospital
  • Harri Rusanen
    • Department of NeurologyOulu University Hospital
  • Jari Hakomaki
    • Medical Imaging CenterTampere University Hospital
  • Arto Lahteela
    • Medical Imaging CenterTampere University Hospital
  • Heikki Numminen
    • Department of NeurologyTampere University Hospital
  • Irina Elovaara
    • Department of NeurologyTampere University Hospital
  • Prasun Dastidar
    • Medical Imaging CenterTampere University Hospital
  • Seppo Soimakallio
    • Medical Imaging CenterTampere University Hospital
Diagnostic Neuroradiology

DOI: 10.1007/s00234-011-0954-z

Cite this article as:
Sillanpaa, N., Saarinen, J.T., Rusanen, H. et al. Neuroradiology (2012) 54: 663. doi:10.1007/s00234-011-0954-z

Abstract

Introduction

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.

Methods

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.

Results

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.

Conclusion

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.

Keywords

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

Abbreviation

ASPECTS

Alberta Stroke Program Early CT Score

AUC

Area under the curve

BASIS

Boston Acute Stroke Imaging Scale

CBV

Cerebral blood volume

C

C statistic

CBS

Clot burden score

CI

Confidence interval

CTA

Computed tomography angiography

CTP

Computed tomography perfusion

H-L

Hosmer–Lemeshow

MTT

Mean transit time

MCA

Middle cerebral artery

NCCT

Noncontrast-enhanced computed tomography

NIHSS

National Institutes of Health Stroke Scale

mRS

Modified Rankin scale

ROC

Receiver operating characteristic

rtPA

Recombinant tissue plasminogen activator

Copyright information

© Springer-Verlag 2011