Prediction of thrombolytic efficacy in acute ischemic stroke using thin-section noncontrast CT

Conventional thrombolytic agents that degrade fibrin/fibrinogen, such as tissue plasminogen activator (tPA), are beneficial in acute stroke patients. However, thrombolysis fails in a significant portion of patients, and harmful hemorrhagic complications occasionally occur. Therefore, predicting which patients would likely fail fibrinolytic treatment may be helpful for choosing other recanalization strategies including new drugs targeted to other components of the thrombus and nonpharmacological treatment using mechanical devices. An animal study showed that erythrocyte-rich thrombi are more sensitive to lysis with tPA than are platelet-rich thrombi.(1) A study using polyethylene tubes as a model of intracranial arteries showed a lower Hounsfield Unit (HU) count in platelet-rich thrombi than in erythrocyte-rich thrombi.(2) Thin-section noncontrast CT (NCT) can detect thrombi in large arteries in acute ischemic stroke.(3) We hypothesized that a thrombus of lower HU count on thin-section NCT is more resistant to lysis than a thrombus with a higher HU count. In this study, we investigated whether the lysability of thrombi in acute ischemic stroke can be predicted by measuring HU count on thin-section NCT.