Yes it's called Minimal Erythemal Dose ( MED) when using a Wound Lamp for healing bed sores, decubitus ulcers, pressure sores.
Minimum Erythemal dose is the amount of ultraviolet light that will cause a barely perceptible redness of the skin within 24 hours of exposure. This amount of dosage was the amount of ultraviolet - c ( UVC) range energy necessary to
stimulate the body to accelerate wound repair or heal itself. UVC is almost never observed in nature because it is absorbed completely in the atmosphere, as are Far UV and Vacuum UV. The V-254 Wound Lamp is a germicidal lamp designed to emit UVC radiation because of its ability to kill bacteria and unlike UV A and B range waves which can cause cancer, UVC does not.
The method used by what were called "UVPTs" ( ultraviolet physical therapists ) was to take a piece of paper and cut three holes in it about the size of a nickel. The UVPT would then take another sheet of paper and cover up two of the three holes while placing the paper with the first hole exposed on the arm of the patient. The wound lamp would be held approximatel one inch away from the hole so the skin was exposed. After 30 seconds the UVPT would move the paper down and now expose the second hole to the lamp and expose that area for 30 seconds before moving down and exposing the final hole on the paper for 30 seconds exposure . When all was done the top skin area had total exposure time of 1.5 minutes ( 90 seconds ), 2nd had total exposure of 60 seconds and final only 30 seconds.
Often a pen would be used to label on the patient's skin the area exposed with "1,2,3" so the UVPT could come back the next day and observe which of the exposed areas now were red. The amount of UVR exposure required to cause perceptible reddening of the exposed skin of fair-skinned people was determined by the UVPT and was referred to as the "med dose" and duly recroded in the patient's chart. Now with darker skin patients it may take longer and rather than looking for redness, darkness was the coloration change expected.
After the MED dose was determined then the therapist knew the dosage from the wound lamp necessary to activate the patient's immune system to help the decubitus ulcer, bed sore, to heal. This exposure would aid the body's natural defense system and speed along the healing process. This was very common treatment post WWII during the time the first line of antibiotics were the sulfa drugs. Later as penicillin became available then the use of UVC was less common
until about 1963 when Medicare was introduced and the physical therapy profession did not have put into the reimbursement codes any fee for doing a UVC treatment. It was then the practice of using UVC for localized and systemic infections faded away. A MED dose was done on the patient only 1 or 2 times per week as most wounds would be healed within a couple of weeks.
Today with the advent of newer technology the actual treatment times are much quicker with the V-254 because the lamp uses mercury vapor technology, not hot and cold quartz.
Since then there has been a steady progression of what are called super germs, inclusive of MRSA and VRE strains, which are resistant to most antibacterial drugs. The progression of the ability of germs to mutate and become stronger now means it's time to use one proven method of bacteria eradication which allowed no new superbugs to come into existence and that is the return of the use of Ultraviolet c range ( 254 nanometer) into our health delivery system.
The leading advocates of wound healing today emphasize that if any single modality could be used in healing wounds they would make it the use of ultraviolet C, not only for killing bacteria, but more importantly for using it to activate our own immune system to do what it does best - heal itself.