European Radiology

, Volume 26, Issue 7, pp 2215–2222 | Cite as

Thrombus length discrepancy on dual-phase CT can predict clinical outcome in acute ischemic stroke

  • Mina Park
  • Kyung-eun Kim
  • Na-Young ShinEmail author
  • Seung-Koo Lee
  • Soo Mee Lim
  • Dongbeom Song
  • Ji Hoe Heo
  • Jin Woo Kim
  • Se Won Oh



The thrombus length may be overestimated on early arterial computed tomography angiography (CTA) depending on the collateral status. We evaluated the value of a grading system based on the thrombus length discrepancy on dual-phase CT in outcome prediction.


Forty-eight acute ischemic stroke patients with M1 occlusion were included. Dual-phase CT protocol encompassed non-contrast enhanced CT, CTA with a bolus tracking technique, and delayed contrast enhanced CT (CECT) performed 40s after contrast injection. The thrombus length discrepancy between CTA and CECT was graded by using a three-point scale: G0 = no difference; G1 = no difference in thrombus length, but in attenuation distal to thrombus; G2 = difference in thrombus length. Univariate and multivariate analyses were performed to define independent predictors of poor clinical outcome at 3 months.


The thrombus discrepancy grade showed significant linear relationships with both the collateral status (P = 0.008) and the presence of antegrade flow on DSA (P = 0.010) with good interobserver agreement (κ = 0.868). In a multivariate model, the presence of thrombus length discrepancy (G2) was an independent predictor of poor clinical outcome [odds ratio = 11.474 (1.350–97.547); P =0.025].


The presence of thrombus length discrepancy on dual-phase CT may be a useful predictor of unfavourable clinical outcome in acute M1 occlusion patients.

Key points

Early arterial phase CTA may underestimate thrombus length.

Thrombus length discrepancy grade reflects collateral status or presence of antegrade flow.

Outcome prediction may be better with thrombus length grade than collateral score.


Brain Infarction Stroke Neuroimaging Tomography, X-Ray computed Middle cerebral artery 



Contrast enhanced CT


Non-contrast enhanced CT


Digital subtraction angiography


Trial of Org 10172 in Acute Stroke Treatment


Modified Rankin scale score


Alberta Stroke Program Early CT Score


Maximum intensity projection


Thrombolysis in cerebral infarction


National Institutes of Health stroke scale


Tissue plasminogen activator



The scientific guarantor of this publication is Seung-Koo Lee. The authors of this manuscript declare no relationships with any companies whose products or services may be related to the subject matter of the article. The authors state that this work has not received any funding. No complex statistical methods were necessary for this paper. Institutional review board approval was obtained. The institutional review board of Yonsei University Health System approved this study and granted a waiver of consent. Some study subjects (n = 34/48) have been previously reported in ‘Dual-phase CT collateral score: a predictor of clinical outcome in patients with acute ischemic stroke. PLoS One 9:e107379’. However, an additional 14 patients were included for this study and the primary aim of the two studies are different. Methodology: retrospective, diagnostic or prognostic study, performed at one institution.

Supplementary material

330_2015_4018_MOESM1_ESM.docx (17 kb)
ESM 1 (DOCX 17 kb)


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Copyright information

© European Society of Radiology 2015

Authors and Affiliations

  • Mina Park
    • 1
  • Kyung-eun Kim
    • 1
  • Na-Young Shin
    • 2
    Email author
  • Seung-Koo Lee
    • 1
  • Soo Mee Lim
    • 2
  • Dongbeom Song
    • 3
  • Ji Hoe Heo
    • 3
  • Jin Woo Kim
    • 4
  • Se Won Oh
    • 5
  1. 1.Department of RadiologyResearch Institute of Radiological Science, Yonsei University College of MedicineSeoulRepublic of Korea
  2. 2.Department of RadiologyEwha Womans University School of MedicineSeoulKorea
  3. 3.Department of NeurologyYonsei University College of MedicineSeoulKorea
  4. 4.Department of Radiology, Ilsan Paik HospitalInje University College of MedicineGyeonggi-DoKorea
  5. 5.Department of RadiologySoonchunhyang University Cheonan HospitalCheonanKorea

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