Helium-neon laser irradiation stimulates migration and proliferation in melanocytes and induces repigmentation in segmental-type vitiligo.

What the authors concluded

The results of this in vitro study revealed a significant increase in basic fibroblast growth factor release from both keratinocytes and fibroblasts and a significant increase in nerve growth factor release from keratinocytes." "In our study group, 60% of patients (18 in 30) presented more than 50% repigmentation and three patients (10%) showed 100% recovery. For treatment control, 20 previously

Devices that emit this wavelength

Matched on wavelength within 15nm, since LED bins vary by roughly that much and a tighter match would be false precision. Where we have an irradiance figure, the session length is the time needed to reach this study's dose of 3 J/cm² at that intensity.

Matching a wavelength is not the same as reproducing a trial. Session times assume the device's published irradiance is accurate at the distance it was measured, which on brand-claim figures is often optimistic. Where a device publishes both a peak and an average we use the average, and where it publishes a falloff curve we use the lowest figure, so these times run long rather than short. Clinical protocols also control for spot size, contact and skin type in ways a home device cannot.