Many patients are curious about the value of integrated dosimetry controllers on home phototherapy devices and specifically wonder what exact benefits are provided for the extra cost. Integrated dosimetry controllers like the Daavlin Flex dosimetry controller measure the actual light output of the phototherapy device in real time, and adjust the treatment length to give exactly the programmed dose. Some benefits can include:
The easiest way to explain the advantage of integrated dosimetry is to show exactly what happens to the power output of a home phototherapy device as it warms up:
The above chart describes the actual measured output of a phototherapy unit in the beginning moments of a treatment. Although not shown, at five minutes, the output in this test case was 22 milliwatts. Therefore, we can see that for the first minute, the lamps emit approximately half of the eventual calibrated output and that the power of the lamps is changing rapidly.
In this example, an initial 15 second treatment using a timer only controller would deliver a dose of 60mJ. If the patient then treated another part of his or her body for 15 seconds, that part of the body would receive about 120mJ in a 15 second treatment.
Or in another way of looking at it, if the desired dose had been 120 milliJoules, then the patient was underdosed by half. With a dosimetry controller, exactly the desired treatment is always given. Even small changes in room temperature, along with other factors, can significantly change the operating characteristics of the lamps.
Everyone is aware of the perils of overdosing, but under-dosing can significantly compromise treatment results as well. When receiving repeated, small, ineffective doses of UV radiation, the skin’s natural defense is photoadaptation. Therefore, the patient will require more treatments to achieve the desired outcome and will require larger doses than optimally necessary to overcome the blocking effects of the increasingly adapted skin. Therefore, not only will lower than prescribed dosages be less effective, they unnecessarily increase the total lifetime dose of UV radiation a patient requires for desired results with a consequent risk of greater long term side effects.
Integrating dosimetry is an effective and time tested way to deliver the exact dosages that have proven to be effective in the therapy of disease. And, integrating dosimeters’ greater therapeutic efficiency conserves lamp life by eliminating the need for stabilizing warm up times and the prolonged therapy caused by under-dosing.