Visualization of injected embolic material (polyvinyl alcohol) in paraffin sections with Verhoeff-Van Gieson elastica stain.

Therapeutic embolization of blood vessels is widely used to treat vascular malformations and to preoperatively decrease the size of bulky tumors by creating iatrogenic infarction. Surgical pathologists are often called upon to identify the presence of embolized material in microscopic slides. Polyvinyl alcohol particles are often used as the material for embolization. On hematoxylin-eosin and other routine stains this substance is almost invisible. These particles stain black and can be sharply outlined by using the Verhoeff-Van Gieson stain.