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Optimizing Photoneuromodulation Techniques to Evaluate the Role of Green Light-Emitting Diodes in Pain Management
Khaled A Ismail1, Victoria Curfman1, Joon Park1
1Department of Anesthesiology, College of Medicine, The University of Arizona, Tucson.
Abstract:
Despite extensive research and the identification of numerous analgesic targets, the range of pharmacological treatments available for pain remains limited. However, a potential paradigm shift could introduce a new wave of non-pharmacological pain treatments with remarkable safety, efficacy, and tolerability. One promising area of investigation is photoneuromodulation using green light-emitting diodes (GLED, 525 nm), which have shown potential in alleviating pain in both acute and chronic conditions, leading to numerous preclinical and clinical studies exploring the efficacy of this therapy. These research projects have demonstrated how exposure to GLED enhances the activity of the endogenous opioid system in the brain and spinal cord after M-cone activation in the retina. The findings suggest that GLED may alleviate pain by modulating the descending pain pathway. In light of the compelling effects of GLED, the proliferation of photoneuromodulation investigations underscores the importance of establishing consistency in well-defined and standardized exposure protocols for preclinical and clinical trials. In preclinical studies, beneficial effects have been observed following a minimum of 2 days of exposure, with protocols involving 8 h of light at 100 lux during the 12 h light phase. In clinical trials, exposure protocols are tailored to the specific pathology under investigation. Exposure for 15 min has proven favorable in the modulation of acute post-surgical pain. For modulation of chronic pain, patients are instructed to use GLED at home for 1 to 2 h a day over 10 weeks. This article details preclinical and clinical protocols to improve reproducibility and consistency in the different studies evaluating photoneuromodulation benefits. By establishing these standardized protocols, this work aims to advance the clinical translation of GLED phototherapy as a viable non-pharmacological treatment for pain.
Insights
Green light-emitting diodes (GLED) show promise for non-pharmacological pain relief by activating the brain's natural pain-killing system. Standardized GLED protocols are crucial for advancing this safe and effective therapy for acute and chronic pain.
Area of Science:
- Neurology
- Pain Management
- Photomedicine
Background:
- Limited pharmacological options for pain management necessitate novel therapeutic approaches.
- Photoneuromodulation presents a promising non-pharmacological strategy for pain relief.
- Green light-emitting diodes (GLED, 525 nm) are being investigated for their analgesic potential.
Purpose of the Study:
- To detail standardized preclinical and clinical protocols for GLED phototherapy.
- To enhance reproducibility and consistency in photoneuromodulation research.
- To advance the clinical translation of GLED as a non-pharmacological pain treatment.
Main Methods:
- Review and synthesis of existing preclinical and clinical GLED exposure protocols.
- Identification of effective GLED parameters for acute and chronic pain modulation.
- Proposal of standardized protocols for future research and clinical application.
Main Results:
- GLED exposure enhances endogenous opioid system activity via M-cone activation.
- GLED therapy modulates descending pain pathways, offering pain relief.
- Specific protocols identified: 8h/day for 2+ days (preclinical); 15 min (acute clinical); 1-2h/day for 10 weeks (chronic clinical).
Conclusions:
- Standardized GLED protocols are essential for consistent and reproducible photoneuromodulation research.
- GLED phototherapy offers a safe and effective non-pharmacological treatment for various pain conditions.
- Establishing clear protocols will accelerate the clinical adoption of GLED for pain management.
