The effect of LED on blood microcirculation during chronic wound healing in diabetic and non-diabetic patients—a prospective, double-blind randomized study


Chronic wounds, especially in diabetic patients, represent a challenging health issue. Since standard treatment protocols often do not provide satisfactory results, additional treatment methods—like phototherapy using low-level light therapy—are being investigated. The aim of our study was to evaluate the effect of phototherapy with light-emitting diodes on chronic wound treatment in diabetic and non-diabetic patients. Since a sufficient blood supply is mandatory for wound healing, the evaluation of microcirculation in the healthy skin at a wound’s edge was the main outcome measure. Forty non-diabetic patients and 39 diabetics with lower limb chronic wounds who were referred to the University Medical Center Ljubljana between October 2012 and June 2014 were randomized to the treated and control groups. The treated group received phototherapy with LED 2.4 J/cm2 (wavelengths 625, 660, 850 nm) three times a week for 8 weeks, and the control group received phototherapy with broadband 580–900 nm and power density 0.72 J/cm2. Microcirculation was measured using laser Doppler. A significant increase in blood flow was noted in the treated group of diabetic and non-diabetic patients (p = 0.040 and p = 0.033), while there was no difference in the control groups. Additional Falanga wound bed score evaluation showed a significant improvement in both treated groups as compared to the control group. According to our results, phototherapy with LED was shown to be an effective additional treatment method for chronic wounds in diabetic and non-diabetic patients.

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The authors thank all patients for their participation, nurses of the Dept. for Surgical Infections for their additional work, and Votan for donating the LED for the purpose of this study.

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Correspondence to Igor Frangez.

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All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

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Informed consent was obtained from all individual participants included in the study.

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Frangez, I., Cankar, K., Ban Frangez, H. et al. The effect of LED on blood microcirculation during chronic wound healing in diabetic and non-diabetic patients—a prospective, double-blind randomized study. Lasers Med Sci 32, 887–894 (2017).

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  • Low-level light therapy
  • LED
  • Microcirculation
  • Chronic wound