Infrared, ultraviolet, and visible light are commonly used to visualize tissues in a variety of ways, but the light is typically not coherent, poorly focused, and not very bright. Researchers at the University of Michigan have been working on a way of getting blood to act like a laser, revealing medically relevant information from within the body. Recently presented at the Conference on Lasers and Electro-Optics in San Jose, California, the research involved using indocyanine green dye that cardiologists, ophthalmologists, and other doctors are well familiar with. The dye was mixed with blood, placed into a reflective chamber called an optofluidic ring-resonator, and illuminated with laser light. The result was that the indocyanine green dye absorbed and then emitted laser light.
It’s not yet clear what various imaging techniques will come of this and what clinical applications will benefit from it, but the researchers believe that in the future they’ll be able to make blood laser in vivo, and as an example maybe lead to tools that can spot high densities of blood vessels that are common within tumors. There’s a lot of work left to tune the technology to achieve that, but the current laboratory capabilities may already be used for some sort of blood analysis and cell imaging.