Selective occlusion of blood supply to the anterior perforated substance of the dog: a highly reproducible stroke model.

We created a highly reproducible stroke model in dogs by the selective occlusion of middle and anterior cerebral artery branches that penetrate the anterior perforated substance and supply much of the basal forebrain. We also analyzed the anatomic organization of the arterial supply to this region in this animal. Perforators came from anterior communicating artery branches similar to the recurrent artery of Heubner in humans and from the middle cerebral artery at several sites distal to the bifurcation of the internal carotid artery. Although some animals had a single source of the perforating arteries, most had two or more. In 50% of our specimens, the anterior communicating artery was the dominant source of arterial supply, in 21% the middle cerebral artery was dominant, and in 24% neither source dominated. Occlusion of all microscopically visible perforators to the anterior perforated substance reliably resulted in infarction of the internal capsule (100%), caudate nucleus (91%-100%), putamen or globus pallidus (82%-91%), and anterior commissure (73%). Structures involved less frequently in infarctions include the external capsule, claustrum, anterior commissure, and septal nuclei. We believe this anatomic information is useful for understanding why previous focal ischemia lesions in the distribution of the middle cerebral artery in the dog have been highly variable as well as for planning and interpreting future studies in this species. The proposed model of focal ischemia may be of use for the study of stroke.