This is a review of an interesting study from 1997 (published in Stroke) that illustrates how vasospastic arteries in a rat subarachnoid hemorrhage model looks like under the scanning electron microscope.
The researchers injected hemolysate (lysed autologous blood) into the cisterna magna of male Sprague-Dawley rats. After ten minutes, a polymer resin casting medium was injected intravenously. Once the resin has casted, the tissue and bones were corroded using NaOH solution, until only the vascular cast remains. The casts were visualized under scanning electron microscope, and the following images were derived: