Thromboangiitis obliterans, or Buerger's disease, is a comparatively rare but extremely unsettling condition, associated with very high levels of pain, often with amputation or reamputation the only surgical recourse. Because of its propensity to be found in the younger patient, it is important that the most minimal surgery possible is indicated, owing to the possibility of the patient's being forced to lead a life of invalidism following the drastic surgery usually needed in this disease, The authors present three cases seen in their institute, all of which would probably have required amputation, or reamputation, Low reactive-level laser therapy (LLLT) was applied in an outpatient setting. using a 10 mW helium-neon continuous wave laser, at doses ranging from 0.18 and 2.7 J/cm². Two of the three patients were completely healed, with a one-year follow-up, and the third patient is still undergoing treatment, but with an excellent prognosis, All three patients reported a significant reduction of pain, and demonstrated fast and significant reduction in inflammation and oedema, accompanied by fast and clear demarcation of the necrotic area, and fast granulation of the ulcer's surface, The wounds healed with minimal scarring, Antibiotics had to be used additionally to the LLLT in two of the three reported cases, Infrared thermography was used to evaluate the effect of LLLT on the microvasculature in the affected area, showing on average a 0.9°C increase in temperature. With what is known about the mechanisms of LLLT on the microvasculature, in particular the improvement in blood flow rate, the authors suggest that LLLT provides a noninvasive therapeutic modality for Buerger’s disease, or any other condition related to microvascular impairment. Further studies on the photoautoimmune effects of LLLT are also needed, as there is a strong connection between autoimmunological processes and this condition.

View full abstract

Macrophages are a source of many important mediators of wound repair. Cells of an established macrophage-like cell line (U-937) were exposed in vitro to one of two light sources with different levels of polarization (95% and 14%), The irradiation times of 60 and 120 s were such that the energy densities to which the cells were exposed were 1.44 and 2,88 J/cm² for each of the light sources, Other groups of cells were sham-irradiated as controls, Twelve h after exposure the macrophage-conditioned medium was removed and placed on 3T3 fibroblast monolayers. Fibroblast proliferation was assessed over a four-day period, The proliferative response was greatest in the cultures exposed to supernatants from macrophages treated with the 95% polarized light source. A treatment time of 120 s was more effective than that of 60 s.

View full abstract

A general mechanism is proposed, capable of accounting for both the stimulating action of visible and infrared lasers on cell cultures, at low laser doses, and the damaging action at larger doses. Laser irradiation is assumed to intensify the formation of a trans-membrane electrochemical proton gradient in mitochondria, This enhances ATP production which activates the Ca²⁺ pumps. depleting the Ca²⁺ concentration in the cytoplasm and increasing the Ca²⁺ concentration gradient of the surrounding medium relative to the cytoplasm. This triggers enhanced Ca²⁺ influx into the cells via the Ca²⁺ ion channels of the cell membrane. In addition, with sufficient irradiation, the proton-motive force (pmf), due to the proton gradient, causes more Ca²⁺ to be released from the mitochondria by an ‘antiport ’ process. The additional calcium transported into the cytoplasm, together with other factors controlled by the pmf triggers mitosis and enhances cell proliferation. At higher laser doses, too much Ca²⁺ is released. This causes hyperactivity of Ca²⁺-ATPase and exhausts the ATP reserves of the cell. The nature of the photoacceptors and possible ways in which the visible and infrared laser energy is converted by the photoacceptors are discussed,

View full abstract