Perfusion- and diffusion-weighted MR imaging-guided therapy of vertebral artery dissection: intraarterial thrombolysis through an occipital vertebral anastomosis.

Management of arterial dissections can be particularly challenging. We report a case of vertebral artery dissection in which perfusion- and diffusion-weighted MR imaging findings suggested the presence of salvageable tissue, despite that the patient had symptoms for more than 40 hours. Direct access to the distal vascular territory was unattainable, and the presence of collateral circulation through an occipital vertebral anastomosis provided the only pathway to administer intraarterial thrombolysis. This case demonstrates that perfusion- and diffusion-weighted MR imaging can be instrumental in the selection of candidates for aggressive stroke therapy. Arterial anastomoses can provide alternate access to ischemic vascular beds and merit careful evaluation during intraarterial thrombolysis.