MR imaging-based decision in thrombolytic therapy for stroke on awakening: report of 2 cases

Abstract

Patients with stroke on awakening are denied the potential benefit of thrombolysis on the grounds that the onset time is unknown. Relying on clinical and MR imaging to indicate the most appropriate treatment could be more rational. We report 2 cases of stroke with unknown onset time. In both cases, anamnesis and MR imaging indicated that we might still be within 6 hours from stroke onset, with salvageable tissue. Arterial recanalization was successfully performed in both cases.

Fig. 1.

Case 1. Before treatment, FLAIR was normal and DWI showed a mildly hyperintense left putamen. Perfusion abnormalities (CBF decrease) existed in the superficial MCA territory, which was normal on DWI (PWI-DWI mismatch). MRA showed a left proximal MCA occlusion. After IA thrombolysis, the flow was restored in the left MCA. A deep MCA infarct with petechiae and a small cortical infarct in the left inferior frontal gyrus (not illustrated) were seen on 24-hour DWI follow-up.

Fig. 2.

Case 2. Before treatment, FLAIR was normal while DWI showed punctuate hyperintensities in the superficial MCA territory (inset) and a left MCA occlusion. Perfusion abnormalities existed in the superficial MCA territory, consistent with a large PWI/DWI mismatch. 24-hour MR imaging follow-up showed an additional lesion in the left putamen and MCA recanalisation after IA thrombolysis.