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A New View of the Cardiovascular System in 3-D

By Sheril Kirschenbaum | October 30, 2015

The parrot had a terminal disease and was entered into the Grey Parrot Anatomy Project at the University of Utah. During this phase of the study, the vasculature was highlighted with BriteVu and revealed previously undescribed anatomic features such as the kinked jugular vein at the lower right of the picture. The kink represents vessel slack and allows the parrot to turn its head without risk of collapsing the large vein. The parrot was scanned at 100 µm. For more details on the anatomy study, click here.

Dr. Scott Echols is a board certified avian veterinary specialist who really loves birds. He thinks it's time we looked at them more closely—literally—and has developed an exciting new imaging technique to do so.

Echols invented a novel non-invasive imaging method to view blood vessels and capillaries with great detail using BriteVu—a high radiodensity contrasting agent containing barium, food grade ingredients and silica.

The discovery began as part of the Grey Parrot Anatomy Project when Echols was searching for a way to visualize an animal's entire cardiovascular system. His team tried myriad commercially available contrasting agents, as well as some homemade agents concocted by fellow researchers. But nothing worked particularly well.

The liver is a highly vascular organ as is seen once perfused with BriteVu. The liver was CT scanned at 70 µm. Studying the vasculature helps researchers understand normal and abnormal organ tissue growth.

Commercially available live animal agents (mostly iodine based) did not remain in the cardiovascular system long enough to create a bright signal on a CAT scan. Terminal agents, used for research purposes in a deceased animal, contained toxic ingredients, had short working times and would not evenly reach many vessels throughout the body. Some destroyed everything but the blood vessels limiting how much of the animal researchers could study. Ultimately, none could produce the kind of detailed image Echols wanted and all of them were expensive.

A pigeon was perfused with BriteVu in effort to study the vasculature of the wings and legs. Because the whole body was evaluated, the head vasculature was isolated showing incredible detail even to the tip of the beak. The pigeon was scanned at 100 µm.

Not discouraged, Echols started to mix his own cocktail in the kitchen. He wanted to create an agent that was easy to use, minimally toxic, inexpensive and able to move from large blood vessels into the capillaries throughout the body. The result was BriteVu.

Images created using BriteVu in rodents and birds were widely shared among researchers. Since its launch this spring, BriteVu has been used across the world in reptiles, birds, mammals and even human cadavers. There are even plans to use the agent in fish and amphibians.

After perfusing the entire mouse with BriteVu, the kidneys were removed and individually scanned at 35 µm. The adrenal glands (bottom and in between the larger kidneys) are visible adjacent to the renal blood vessels.

The images and data produced allow researchers to view the cardiovascular system in its undisturbed three-dimensional position in greater detail than ever before without altering surrounding tissues. Ultimately BriteVu has the potential to help advance:

Anatomy: Even today, our understanding of vascular anatomy has mostly been limited to gross dissection, photography, drawings, crude computer renderings and very localized (usually single organ) contrast perfusions (primarily on rodents). With BriteVu, researchers can look at the entire cardiovascular system without disrupting tissues. This allows scientists to see exactly how arteries and veins sit within the body in 3-D! The resulting knowledge can inform students in classrooms and physicians, like surgeons needing to know where vessels sit in order to avoid excessive bleeding during operations.

Embryology: BriteVu can be used to visualize the progressive development of blood vessels (angiogenesis). This helps researchers understand how animals develop and the visuals can also teach them more about gene expression.

Disease: Many diseases, such as cancer and infections, rely on a robust blood supply, or lack thereof, to develop. BriteVu can be used to define the relationship between diseases and their blood supply. This not only helps us understand the development of disease but also helps target new treatments.

Pharmaceuticals: Most pharmaceuticals require the drug be distributed through the cardiovascular system. By understanding the vascular supply in diseases, developmental disorders and basic anatomy, drugs can be better designed to reach specific targets.

I'm looking forward to learning—and viewing—more from Echols and BriteVu.

All images and video courtesy of Scott Echols and Scarlet Imaging, LLC

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