Thrombus Length Evaluation on Multiphase CT Angiography in Acute Ischemic Stroke Patients


  • Sasitorn Petcharunpaisan -
  • Montira Chancharoenchai
  • Krittanon Lertutsahakul


acute ischemic stroke, MCA occlusion, thrombus length evaluation, multiphase CTA


Background: In acute ischemic stroke (AIS) patients with proximal middle cerebral artery (MCA) occlusion, estimation of the thrombus length can be helpful for pre-procedural planning of the endovascular thrombectomy.

Objectives: To evaluate the thrombus length measurement on multiphase computed tomography angiography (mCTA) compared to the reference standard cerebral digital subtraction angiography (DSA).

Methods: Forty-five AIS patients with acute occlusion of proximal MCA underwent both mCTA and DSA were retrospectively reviewed. Thrombus length was measured on the two imaging planes of mCTA, the coronal plane and the plane parallel to arterial course, and on the anteroposterior view of DSA. We evaluated overall agreement between the measurement on the mCTA and DSA, subgroup assessment according to different thrombus location and different thrombus length, and interobserver agreement.

Results: There was overall good agreement between the measurement on DSA and both planes of mCTA. There was substantial agreement for the different thrombus location (M1, M2 and M1-M2) between mCTA and DSA, except for moderate agreement of the M1-M2 thrombus on the mCTA coronal plane. There was fair agreement across three different thrombus length (<10 mm, 10–15 mm, and >15 mm) between mCTA and DSA, except for slight agreement for the 10–15 mm thrombus on the mCTA coronal plane. The inter-observer agreement was excellent. There was no significant association between the thrombus length and the successful recanalization.

Conclusion: Thrombus length measurement on mCTA is applicable and can be practically useful in the acute stroke imaging for patient selection to endovascular thrombectomy.


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How to Cite

Petcharunpaisan S, Chancharoenchai M, Lertutsahakul K. Thrombus Length Evaluation on Multiphase CT Angiography in Acute Ischemic Stroke Patients. J Thai Stroke Soc [Internet]. 2023 Apr. 12 [cited 2024 Jun. 14];22(1):21. Available from:



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