How does Cooling Tissue before laser impact penetration?
Do you ever wonder if your laser energy is getting deep enough into the tissue? Maybe you wish you could get better penetration into the tissue, or perhaps you just want to use less energy and still get maximum penetration. Today we’re talking about cooling tissue before lasering and how that affects the depth of penetration.
Common areas we want deep penetration include hip joints, the abdominal organs, the chest cavity to treat the heart or lungs, and dense connective tissue e.g. the calcaneal tendon.
So how can we get lasers to go deeper?
Watch the video below to learn about research that’s been done on cooling tissue before using different types of lasers.
*Please note that this video was created for veterinary professionals.
A 2017 study looked at how well lasers penetrated humans’ achilles tendons after 20 minutes of cryotherapy (ice). They compared how much energy passed through the tendons using an 810 nm 200 mW laser on continuous mode and a 904 nm 60 mW laser on superpulsed mode (superpulsed lasers produce high power impulses for brief durations that go deeper into tissue without creating heat).
There were differences in the original penetration as we well as penetration after the cryotherapy.
The 904 nm laser penetrated tissue better overall even though the average power was only 60 mW compared to the 810 nm that had 200 mW continuous power. Wavelengths play a big part of penetration and effect.
The 904 nm wavelength had an approximately 33% increase in penetration after icing compared to the 810 nm laser that had an approximately 25% increase in penetration after icing.
What’s causing the difference in penetration? It may be that since there is less blood in the tissue due to vasoconstriction and therefore less heme from the red blood cells, there is less absorption of the photons and so more penetration. It may also be that there is less tissue. In the study, they measured the width of the tendon, and the tendons were thinner after the cryotherapy. My guess is it is a combination of both and potentially other factors that we are not aware of at this time.
If you’re a member of our Optimum Laser Therapy Course, definitely check out Module 36: Pneumonia to learn about treating the lungs.