LED Therapy for the Treatment of Concussive Brain Injury

Concussion, also known as mild traumatic brain injury (mTBI), results from a rotational acceleration of the brain. The biomechanical forces which cause concussion lead to the opening of ion channels within the neuronal cell membranes, allowing for a massive influx of sodium and efflux of potassium. This results in a spreading depression type of phenomenon, leading to the depolarization of neurons diffusely throughout the brain.19 In order to restore the homeostatic ion gradients across the membrane, the sodium-potassium pumps require increasing amounts of adenosine triphosphate (ATP). Thus, there is an increased need for ATP after concussion. ATP is supplied by the glycolysis of glucose from the blood stream. Both experimental models of concussion and human studies, however, show decreased cerebral blood flow after the initial response to injury. Thus, there is an increased demand for ATP after concussion; but a diminished supply of glucose to meet the demand. The absorption of light in the red/near infrared wavelength spectrum by cytochrome C oxidase increases ATP synthesis. Thus, by increasing ATP synthesis, red/near infrared LEDs can treat the underlying pathophysiological cause of concussion symptoms. If successful, this would be the first therapy to directly treat the underlying pathophysiology of concussion.