Bubbles in the blood may sound like a bad idea — but if they're small, they can actually prove useful instead of dangerous. This is image shows how they can be used to create images of our blood vessels with unprecedented detail.
Created by Kirsten Christensen-Jeffries from King's College London, this is an ultrasound image of the blood vessels in a mouse's ear. Usually so small that they're impossible to make out clearly without a microscope — a red blood cell only just fit through these vessels, which are just 10 microns in diameter — here they're plain as day. The colour in the image shows the flow in different vessels, and the brightness shows speed too. The research is published in IEEE Transactions on Medical Imaging.
How does it work? Well, those microbubbles are tiny pockets of gas, which provide a huge contrast in density to the material surrounding them, which is all more akin to water — tissue, blood and the like. When ultrasound hits the bubbles, the big difference in density provides a very clear echo that's sent back the ultrasound device and shows up brightly on the resulting images.
Its imaging techniques like this that allow scientists to understand how cancerous tumors first start to grow — and might some day give us a deeper understanding of how we can prevent them from developing at all. [IEEE Transactions on Medical Imaging via New Scientist]