1. laser therapy, low-level Treatment using irradiation with LASER light of low power intensity so that the effects are not due to heat, as in LASERTHERAPY. These non-thermal effects are thought to be mediated by a photochemical reaction that alters CELLMEMBRANE PERMEABILITY, leading to increased mRNA synthesis and CELL PROLIFERATION. Low-level laser therapy has been used for a wide variety of conditions, but most frequently for woundhealing and pain control.