Cells breathe. They need oxygen, and they take it from the blood flowing through the tiniest vessels. If blood flow is weak or oxygen is scarce, cells start to suffocate. Doctors need to see this as early as possible. But how do you look inside living tissue without cutting it open?
The new device does it in two ways at once. The first way is like a flashlight that shines on the tissue and, based on the reflected light, determines how much oxygen is in the blood. The second is like high-speed camera footage, where the flickering of laser speckles reveals how fast the blood is moving. Both methods work with a single camera, alternating the light: first one, then the other.
The device was tested on a rat's spinal cord. First, the animal breathed normal air; then, oxygen was reduced. The device immediately noticed: blood flowed more slowly, and cells began to use oxygen differently. This means the device can monitor tissue health in real time, like taking a pulse, but deeper.
Such a device would be useful in hospitals. For example, during brain or heart surgery, a surgeon could see if tissues are suffocating. It could also be used to study how drugs that improve blood flow work. Cells breathe, and now we can see it.
The device uses two lasers: one white, like a rainbow, and one red, like a laser pointer. They alternate, and the camera captures both signals.