Brought to you by the GOAT: Laurie Edge-Hughes, BScPT, MAnimSt, CAFCI, CCRT
This is a topic that I have discussed in the past, but a recent article brought it to my attention again. So, let’s talk about lasering the brain!
Why would you want to laser the brain?
Simply put, Laser (photobiomodulation – PBM) can stimulate healing. As such, there are pathologies in the brain that laser could potentially heal!
Canine cognitive dysfunction (i.e. Alzheimer’s), brain injuries, stroke, middle and inner ear infections, any issue impacting the brain stem (i.e. syringomyelia, GOLPP), or perhaps cerebellar hypoplasia could all benefit from laser therapy.
How might laser work to impact the brain?
• PBM can stimulate mitochondria in the brain to produce ATP and subsequently enhance energy for the brain. It has been shown that 660 and 810nm wavelengths are best at stimulating the mitochondria.
• Transcranial-PBM can reduce amyloid plaque build-up in the brain via modifying microglial activity, most likely via increased beta-amyloid plaque phagocytosis and improved blood supply (angiogenesis). It has been shown that 1070nm wavelength reduce amyloid plaque levels in mice, and 632.8nm also showed positive effects.
• Laser therapy has been shown to enhance Brain-Derived Neurotrophic Factor invitro, having a restorative effect on neurons of the hippocampus.
• Anti-inflammatory and antioxidant effects have been shown to play a factor. Brain blood flow is also enhances with PBM. An 808 nm wavelength was shown in a mouse model to increase cerebral blood flow by 30%.
There are no scientific papers that have studied laser therapy for canine cognition (or other pathologies). As such, we must look to rodent studies to extrapolate. An approximate dose for rodents of 10 J/ cm2 and a range of 25–60 J/cm2 for people have been approximated based on various studies.
I have found a suggestion to aim for 0.3 – 3.0J/cm2 at the target tissue. Hmmm. I have also seen that only 1 – 6% of the joules delivered at the surface will reach the target tissue when penetrating through layers of multiple tissue types. So it is likely safe to say that you would be unlikely to over-laser. However, as a starting point, one could try the doses listed above.
Clinically, I have lasered for syringomyelia and GOLPP, and for residual effects after resolution of a deep inner ear infection, however, I’ve not had the chance to use PBM for canine cognitive dementia. If you have, I’d LOVE to hear your thoughts!
Dewey CW, Brunke MW, Sakovitch K. Transcranial photobiomodulation (laser) therapy for cognitive impairment: A review of molecular mechanisms and potential application to canine cognitive dysfunction (CCD). Open Vet Journal, 2022, V12(2): 256 – 263.