Related Experiment Video
Updated: May 11, 2026
Transient Middle Cerebral Artery Occlusion Model of Stroke
Published on: August 11, 2023
Clot burden score on admission T2*-MRI predicts recanalization in acute stroke
Laurence Legrand1, Olivier Naggara, Guillaume Turc
1Department of Radiology, Centre Hospitalier Sainte-Anne, Université Paris Descartes Sorbonne Paris Cité, Centre de Psychiatrie et Neurosciences, INSERM S894, Paris, France.
Background And Purpose:
To propose a T2*-MR adaptation of the computed tomography angiography-clot burden score (CBS), and assess its value as predictor of 24-hour recanalization and clinical outcome in anterior circulation stroke treated by intravenous thrombolysis ≤4.5 hours from onset.
Methods:
Two independent observers retrospectively analyzed pretreatment T2* images for evaluation of clot burden, using a 10-point scale T2*-CBS. Three points are subtracted for susceptibility vessel sign in the supraclinoid internal carotid artery, 2 points each for susceptibility vessel sign in the proximal and distal part of middle cerebral artery, and 1 point each for susceptibility vessel sign in middle cerebral artery branches (with a maximum of 2 points) and for susceptibility vessel sign in anterior cerebral artery. Associations with 24-hour recanalization and favorable outcome (3-month modified Rankin Scale score, ≤2) were assessed in multivariate analyses.
Results:
We analyzed 184 consecutive patients (mean age, 67 years) with median (interquartile range) admission National Institutes of Health Stroke Scale score and onset-to-treatment time of 15 (9-19) and 151 (120-185) minutes, respectively. The intraclass correlation for T2*-CBS between observers was 0.97 (95% confidence interval, 0.97-0.98). In multivariate analyses, T2*-CBS >6 was significantly associated with 24-hour recanalization (adjusted odds ratio, 5.1 [1.9-13.5]; P=0.001) or with favorable outcome (adjusted odds ratio, 4.2 [1.7-10.8]; P=0.003).
Conclusions:
T2*-CBS, a new reproducible semiquantitative score adapted from the computed tomography angiography-CBS, is associated with 24-hour recanalization and 3-month outcome after intravenous thrombolysis. This score needs external validation and could be useful to identify poor responders to intravenous thrombolysis.
Insights
A new T2*-weighted MRI clot burden score (CBS) accurately predicts recanalization and outcomes in stroke patients receiving intravenous thrombolysis. This reproducible score helps identify patients unlikely to respond well to treatment.
Area of Science:
- Neurology
- Radiology
- Medical Imaging
Background:
- Acute ischemic stroke treatment relies on reperfusion therapies.
- Computed tomography angiography (CTA) clot burden score (CBS) aids in predicting treatment response.
- A non-contrast MRI adaptation is needed for broader clinical application.
Purpose of the Study:
- To adapt the CTA-CBS for T2*-weighted MRI (T2*-CBS).
- To evaluate T2*-CBS as a predictor of 24-hour recanalization and clinical outcome.
- To assess T2*-CBS in anterior circulation stroke patients treated with intravenous thrombolysis.
Main Methods:
- Retrospective analysis of pretreatment T2*-weighted MRI scans in 184 stroke patients.
- Application of a 10-point T2*-CBS based on susceptibility vessel sign presence and location.
- Multivariate analyses to assess associations between T2*-CBS and recanalization/outcome.
Main Results:
- High inter-observer reliability for T2*-CBS (ICC=0.97).
- A T2*-CBS >6 was significantly associated with 24-hour recanalization (aOR=5.1) and favorable 3-month outcome (aOR=4.2).
- Patients with T2*-CBS >6 showed improved outcomes after thrombolysis.
Conclusions:
- T2*-CBS is a reproducible MRI-based score predicting recanalization and outcome.
- This score can identify patients who may not benefit from intravenous thrombolysis.
- External validation is recommended for widespread clinical adoption.
