Bilateral Paramedian Thalamic Contrast Enhancement on CT after Intra-arterial Thrombolysis

A 58-year-old woman presented with an acute embolic occlusion of the distal basilar artery. She underwent angioplasty and intra-arterial thrombolysis. Angiography performed after recanalization revealed a single perforating thalamic artery. A nonenhanced CT scan carried out immediately after the procedure revealed hyperdense lesions in the bilateral paramedian portions of the thalami, which disappeared on the 24-hour follow-up CT scan. Three months later, the patient improved to functional independence, but had some memory dysfunction and vertical gaze palsy. This case suggests that contrast enhancement or extravasation can occur in the thalamus after intra-arterial thrombolysis performed to recanalize a basilar artery occlusion.