New and reproducible technique for experimentally induced middle cerebral artery stenosis

A reproducible technique has been developed to create reversible middle cerebral artery (MCA) stenosis in the cat. Under pentobarbital anesthesia, the right eye was enucleated, MCA dissected and a suture looped around the vessel. A short segment of thicker suture was set horizontally on the MCA. The looped suture was then tied and the segment suture removed, resulting in partial stenosis. The knot could be easily removed, restoring blood flow. Perfusion and diffusion-sensitive magnetic resonance (MR) images were obtained over the next 6 hours to document cerebral blood flow abnormalities and developing ischemic changes, respectively. Laser-Doppler was performed to further document reduced flow through the ipsilateral hemisphere following MCA stenosis. Histopathologic sections were assessed for ischemic damage. Our results show this to be a reliable model of MCA stenosis and reperfusion, which is suitable for the evaluation of acute cerebral perfusion abnormalities resulting from arterial stenosis.