Phototherapy, as it’s called, usually involves using a single wavelength of light that has been identified as having a particular property.
For example, blue light has been explored as a treatment for pain as it can stimulate the body’s production of nitric oxide, which widens blood vessels, increasing blood flow to the area, and this in turn is thought to increase the supply of pain-relieving molecules.
Ultraviolet light - the type of light that burns the skin and is also used in sunbeds - has been found in small and controlled amounts to have antimicrobial and anti-inflammatory properties, and has been tested as a way to treat skin conditions such as acne and eczema.
Now doctors at Salford Royal NHS Foundation Trust have combined three types of light - red, ultraviolet and infrared - to deliver a triple whammy to ulcers.
They have built a special lamp with 32 different bulbs, which emit infrared, red or ultraviolet light. Together they are thought to speed up healing through various mechanisms.
In a recent trial, doctors found the therapy was effective in treating ulcers on the tips of the fingers caused by systemic sclerosis, where the immune system mistakenly attacks connective tissue and causes ulcers and sores on extremities.
But NHS doctors say it could also be used for other ulcers, including diabetic foot ulcers, and bed sores, which affect more than a million patients a year. People with diabetes are at risk of ulcers or open wounds that don’t heal because of poor circulation.
Bed sores can affect anyone who remains in one position, such as those in hospital or who cannot move much because of illness, old age or frailty. The constant pressure of the sheets or mattress can cut off blood flow to an area of skin and tissue, and it starts to break down.
The new light therapy works in a number of ways. Ultraviolet light, which cannot be seen by the naked eye, is thought to kill the bacteria and reduce the inflammation that prevents proper healing.
Red light, which falls into the visible part of the light spectrum, is believed to boost blood circulation, increasing the supply of oxygen and nutrients needed for wound healing.
Infrared light, used in TV remote controls, is thought to increase blood flow and oxygen.