Low-level laser therapy (photobiomodulation) versus hyperbaric oxygen therapy on healing of chronic diabetic foot ulcers: a controlled randomized trial

Abstract

Background and purpose Diabetic foot ulcers (DFU) and concurrent infections are the most frequent complications in patients with diabetes mellitus. Both low-level laser therapy (LLLT), photobiomodulation (PBM), and hyperbaric oxygen therapy (HBOT) promote the healing of wounds. The purpose of this study was to compare the effectiveness of LLLT versus HBOT on the healing of chronic DFU. Patients and methods: Seventy-five patients with chronic diabetic ulcers aged ranging from 40–65 years were recruited and assigned randomly into three groups. HBOT group received 100% pure oxygen 2.5 ATA delivered for 60 min per session for 30 sessions (5 sessions per week for 6 successive weeks). LLLT group received GaAlAs diode laser producing a total power output of 1440 mW with following wavelengths: 5 × 850 nm (200 mW), 12 × 670 nm (10 mW),8 × 880 nm (25 mW), and 8 × 950 nm (15 mW); the energy density (fluency) was adjusted for 4 J/cm2 with a pulse frequency of 10 kHz. Each session lasted 8 min every two days. The control group received conventional wound care only (wound cleansing twice daily using saline or similar dressing). Both LLLT and HBOT groups received conventional wound care in addition to their program. Measurements for ulcer surface area (USA; transparency method) and ulcer volume (volumetric method) were performed before starting the study and in the second, fourth, and sixth-weeks post-treatment. Results: Within group comparisons demonstrated a statistically significant decrease in USA and ulcer volume in both HBOT and LLLT groups (p-value = 0.0001 in all measurements). The multiple comparisons between groups for USA, there was insignificant difference between HBOT and LLLT groups after 2-, 4-, and 6-weeks (p-value = 0.48, 0.813, and 0.629, respectively), while for ulcer volume, there was a statistically significant difference in favor of the LLLT group only after 2- and 4-weeks (p = 0.037 and 0.042, respectively) while an insignificant difference after 6-weeks (p-value = 0.911). Conclusion: Both LLLT and HBOT accelerate healing in chronic DFU, but the LLLT is more favorable in decreasing ulcer volume after during the first 4-weeks.