The General optical Council (GOC), the UK regulators for optometrists and dispensing opticians, has decided to approve treatment of dry age-related macular degeneration (AMD) using photobiomodulation treatment.
This is a light delivery mechanism of a multi-wavelength source that targets sub cellular regions of a cell causing the cellular mitochondria to elicit more energy. Current nascent treatment modalities are being used in practice by Vikash Kumar Optometrist.
Macular degeneration is the leading cause of blindness in the over 65s, with dry AMD accounting for 90% of macular degeneration and wet accounting for 10%. Treatment with low level energy light is now indicated for the dry type of AMD, as well as ocular damage caused by oedema, inflammatory mediators, the wound healing response and drusen deposition. The results are very positive with patients reporting an improvement in visual acuity and contrast sensitivity. Presently, there are no other treatment modalities for dry AMD. This modality is CE marked and under rigorous testing in the USA.
How Does it Work?
The instrument uses LEDs to target individual subcellular units at wavelengths of 590nm, 660nm and 850 nm respectively. This is in the far red and near InfraRed NIR spectral range. The higher wavelengths, 660 and 850 nm target the photoacceptors in the cellular enzyme, cytochromo c oxidase (CCO) by promoting electron transfer and oxygen binding within the CCO. This results in increased cellular mitochondrial activity and metabolism and hence an increase in energy production and subsequent reduction in cellular inflammation and cell death. The 590 nm wavelength has 2 functions: a) it naturally inhibits the protein VEGF ( vascular endothelial growth factor) which would normally cause the proliferation of new blood vessels in wet AMD and promotes the production of nitric oxide which promotes oxygen and inhibits cell inflammation and death.
Mitochondrial Dysfunction and Oxidative Stress play a key role in Age-Related Macular Degeneration
As oxidative stress can cause mitochondrial dysfunction, targeted photobiomodulation therapy can result in increased metabolism and cell preservation. Retinal cells are one of the most energy dependent cells in the body.
How are Treatments Carried out?
For mild to moderate dry AMD, 9 treatments are carried out over a 3 week period per eye. Treatments last for 5 minutes.
It is estimated that 200 million people will be afflicted with AMD by 2021.. The dry type of the disease is characterised by drusen, a metabolite waste product that accumulates primarily in the macula. This causes “irreversible” sight loss. Prior to photobiomodulation, treatment involved the use of supplements and vitamins and lifestyle changes with arguable success. The earlier the AMD is diagnosed by an optometrist, the better the prognosis for treatment.
The LIGHTSITE I study is the first prospective, sham controlled, double-masked clinical study to evaluate the effectiveness of photobiomodulation (PBM) treatment in patients with dry age-related macular degeneration (AMD). The study included 46 eyes and subject participation lasted 12 months. Results from the LIGHTSITE I study showed clinical improvements in visual and anatomical outcome measures following multi-wavelength PBM. Improvements were observed in Best-Corrected Visual Acuity (BCVA) and Contrast Sensitivity (CS) in addition to improvements in pathological hallmarks such as Central Drusen Volume (CDV). These data provide a strong foundation for the utility of PBM therapy and demonstrate disease-modifying effects.
The PBM therapy (three treatments per week for three weeks) was most beneficial in dry AMD patients immediately following the completion of the treatment sessions highlighting a need for follow-up maintenance therapy. Retreatments at a six-month interval were performed to maintain clinical benefits.
No device-related adverse events were reported throughout the course of the study highlighting a favorable safety profile. The results demonstrate that the therapy is both a safe and effective treatment for early stage dry AMD patients.
To learn more, reach Vikash Kumar Optometrist