Why is the ocean blue? And what does that have to do with premature babies? The ocean is blue because water acts like a color filter, absorbing the red portion of the spectrum, and reflecting back shades of blue. The fact that different substances absorb different wavelengths of light may show the way to helping premature babies survive.

One of the many challenges facing premature babies is that their lungs often are not developed enough to allow the child to breath without assistance. Monitoring the size and status of the lungs is of primary importance, yet the standard practice at this point is to use X-ray imaging. This process poses additional hazards of its own. A doctoral candidate at Lund University in Sweden has written a thesis on a non-invasive approach using light. By shining light from a laser through the infant’s body, the absorption of different wavelengths can indicate both oxygenated blood and free oxygen molecules in the lungs. This means that it is possible to avoid the use of potentially harmful X-rays, and even provide continuous monitoring of the patient.

The researcher also describes ways that this technology can be applied to adult patients, especially victims of sever trauma. The light method can be used to detect oxygen levels and blood flow in limbs that can be deprived of blood if the body goes into shock. The ability to detect oxygen levels with a non-invasive process could help save lives.