Condition Focus: Microcirculation — Immediate and Sustained Capillary Flow Enhancement

The question of whether PBM actually improves blood flow — not just in theory, but measurably and quickly — is directly answered by this randomised controlled trial from Gavish and colleagues, published in Lasers in Surgery and Medicine, one of the premier journals in the field.

Using real-time microcirculation monitoring, the researchers demonstrated that just 5 minutes of PBM at either 633 nm (red) or 830 nm (NIR) induced an immediate increase in capillary blood flow. The effect was not transient — it was sustained beyond the treatment period, indicating that PBM triggers a biological vasodilatory response rather than simply providing local heating.

The RCT design with sham controls confirms that the capillary flow increase is a genuine biological effect of photon absorption, not a placebo response or artifact of the measurement technique. The dual-wavelength finding (both 633 nm and 830 nm effective) supports the rationale for devices that combine red and NIR wavelengths.

For gout, microcirculatory improvement at the joint level has three direct benefits: delivering oxygen to hypoxic inflamed tissue (reducing the oxidative stress that drives NLRP3 activation), removing dissolved urate and inflammatory debris from the joint space, and supporting the metabolic needs of cells engaged in tissue repair. A treatment that achieves measurable perfusion improvement in 5 minutes addresses the immediacy that gout patients need during an acute flare.

G.O.A.T. for Gout Alignment:
The G.O.A.T.’s 660 nm + 850 nm wavelengths parallel the 633 nm + 830 nm tested here. The 5-minute onset of effect supports the G.O.A.T.’s ~13-minute session protocol — capillary flow improvement begins within the first few minutes and is sustained through and beyond the treatment session.

Link to original research here

Editor’s note: The NO-mediated mechanism underlying this capillary flow increase is detailed in Keszler et al 2023. The first human in vivo NO measurement confirming deep tissue effects at 850 nm is in Barolet et al 2024. The eNOS phosphorylation driving sustained vasodilation is mapped in Yokomizo et al 2022. For the lymphatic drainage that complements vascular perfusion for joint clearance, see Lymphedema Systematic Review 2022.

Related Articles

• PBM and Nitric Oxide Signaling – Keszler et al 2023
• In Vivo NO Release from Human Skin Post PBM – Barolet et al 2024
• NIR PBM Augments NO via eNOS Phosphorylation – Yokomizo et al 2022
• PBM for Lymphedema: Systematic Review of RCTs – 2022
• CCO as Nitrite Reductase: Novel PBM Function – Poyton & Ball 2011

Key Takeaways

• RCT with sham control: 5 minutes of PBM induces immediate, sustained capillary flow increase
• Both 633 nm and 830 nm effective — supports dual-wavelength device design
• Sustained beyond treatment — genuine biological vasodilatory response, not transient heating
• Published in Lasers in Surgery and Medicine — premier journal in the field

Study Overview

Full Citation

Gavish L, et al. (2020). Microcirculatory response to photobiomodulation — why some respond and others do not: a randomized controlled study. Lasers in Surgery and Medicine, 52(9), 863–872. View Publication