New research on light therapy shows promise for patients who have suffered repetitive head impacts and may have CTE based on their medical history
This blog post is a special in-depth report by Concussion Alliance contributor and intern Julian Szieff, and Concussion Alliance co-founder Malayka Gormally. We recommend reading our Light Therapy page for in-depth information.
Research on light therapy (photobiomodulation, PBM) by Margaret Naeser, PhD at the Boston VA Medical Center, and Boston University School of Medicine, Neurology, has expanded to encompass preliminary, but compelling research into the possible treatment of chronic traumatic encephalopathy, or CTE. According to the Mayo Clinic, CTE is “the term used to describe brain degeneration likely caused by repeated head traumas,” and there is currently no cure for it. A living person cannot be given a confirmed diagnosis of CTE, because CTE can only be diagnosed by studying sections of the brain during an autopsy.
In Dr. Naeser’s recent two case studies, the men had undergone years of repetitive head impacts as former professional football players and were exhibiting signs of progressive neurodegenerative disease.
At the International Brain Injury Association (IBIA) conference in Toronto (March 2019), Naeser presented two case studies which showed positive results from photobiomodulation treatments in two retired, professional football players who were diagnosed with cognitive decline and with symptoms of possible CTE. One of the two cases incorporated baseline and follow-up fMRI scans, in addition to numerous clinical tests. Naeser’s abstract of the case studies was published in the journal Brain Injury.
This research is the first study showing positive brain imaging changes on functional MRI scans after a series of photobiomodulation treatments in a retired, professional athlete.
The changes on fMRI scans occurred in tandem to changes in behavior, suggesting that the near-infrared were passing through scalp and bone, to reach the surface brain cortex. Thus, application of PBM to the scalp PBM may a possible treatment approach for CTE.
This video chronicles the remarkable recovery of BYU Hall of Famer Larry Carr from brain damage due to football through the use of red and near infrared light therapy. Credits: Dr. Larry Carr at Football and the Brain and Gabe Golden at Golden Film Productions.
How significant were the results of light therapy?
When Dr. Naeser tested the men at the entry to the study, both had significant levels of PTSD (emotional outbursts), depression, and cognitive decline. After the six weeks of in-clinic light therapy, the men had significantly reduced PTSD and depression, and both experienced dramatic cognitive, language, and memory improvement. These results were validated by clinical tests, and with fMRI scans for one of the men. This article includes some of Dr. Naeser’s slides of the results of the clinical tests and the fMRI scans.
Case study #1
For case study #1, Dr. Larry Carr, the positive changes slipped away two months after the end of the in-clinic light therapy. At that point, Dr. Carr purchased in-home light therapy devices, the Vielight Neuro Gamma and the Vielight 633 Red intranasal. Dr. Carr’s preferred schedule was M-W-F for the Vielight Neuro Gamma and six days a week for the Vielight 633 Red intranasal. More information about these devices is on our Light Therapy page. After three months of in-home light therapy, Dr. Carr regained his improvements. These improvements were verified by subsequent clinical tests and fMRI scans.
In a blog post, Dr. Carr reports that after three months of using the in-home Vielight treatment, he had no PTSD and no depression. He also had highly significant improvements in cognition, such as executive function. Laurie Carr writes in a blog post:
But somehow we found the VA, somehow we found a treatment that works, and it has made all the difference in the world to us…The person he became, paranoid, suspicious, anxious, agitated, and annoyed is gone. I have my husband back…suicidal thoughts no longer cloud his mind. He is the happy, calm, peaceful, logical man I married almost 47 years ago.
Case study #2
After the in-clinic light therapy, case study #2 also had dramatic improvements in all symptoms areas, including PTSD, depression, and cognition. These improvements were verified with clinical tests at one week and one month after the end of the treatments. Additionally, the study called for clinical tests at two months after the end of the in-clinic treatments.
Concerned about losing all of his improvements, case study #2 dropped out of the study after one month without light therapy. He purchased a Vielight Neuro Gamma and started doing in-home light therapy treatments. Dr. Naeser continues to hear that he is doing well, almost a year later.
In this interview with Vielight, Dr. Naeser discusses transcranial photobiomodulation (tPBM) as a possible treatment modality for traumatic brain injury (TBI) and in retired professional football players who may be developing chronic traumatic encephalopathy (CTE).
Theories on how light therapy works
Laboratory studies have found that light therapy (with red and near-infrared light (810nm) light) increases the ATP (or energy production) in hypoxic cells. Hypoxic cells are cells which lack oxygen due to injury or disease.
Studies with humans (in 2009, 2012, 2019 and 2019) have found that light therapy widens blood vessels (vasodilation), thus increasing blood flow, in limited, specific areas in the brain. This increased blood flow is related to an enzyme in the mitochondria (the cells “powerhouse”) getting rid of toxic nitric oxide due to increased vasodilation.
Connectivity between areas of the brain can become dysfunctional after a brain injury; a 2018 study found that light therapy improves brain connectivity and cognition. Proper functioning of the Default Mode Network (DMN) is related to cognition, including executive function; read about the DMN and light therapy article by Dr. Naeser in Vielight for more information.
From Naeser’s poster presentation at the March 2019 International Brain Injury Association (IBIA) conference in Toronto.
Background: Dr. Naeser’s earlier light therapy study for mTBI
In terms of the history of her research, Naeser’s first study in 2014 (Naeser, Zafonte et al., 2014, Journal of Neurotrauma) found that a series of photobiomodulation treatments resulted in improvements in cognition (executive function and verbal memory), sleep, and quality of life in eleven patients with chronic, closed-head mild traumatic brain injury (mTBI). There was also a reduction of PTSD symptoms in the four cases who had problems with emotional outbursts.
In the 2014 study and throughout her research, Naeser has employed a variety of light therapy equipment made by different companies; treatments are applied by using red/near-infrared LED devices on the head, and newer studies have added an LED device clipped into a nostril.
Case Study #1 - retired pro football player Dr. Larry Carr
Dr. Larry Carr’s website, Football and the Brain
Larry Carr and his wife
In 2017, Naeser was approached by Larry Carr, PhD, a former BYU football player known for his defensive tackling. Dr. Carr had been struggling for at least ten years with symptoms highly resembling CTE, including emotional outbursts, depression, poor cognition and memory, as well as poor sleep. Seeking help with his symptoms and contemplating suicide, he asked Naeser to include him in her research.
Carr became the first of Naeser’s two case studies with former professional football players who were possibly developing the progressive neurodegenerative disease, chronic traumatic encephalopathy (CTE). Dr. Carr is a Brigham Young Hall of Fame player; he holds his college record for most tackles (700+). He estimates that he has suffered over 3,000 hits to the head throughout his career, from Pop Warner football at age ten, to BYU, to one and a half years in the Canadian Football League.
After obtaining a PhD and enjoying a career as a professor, Dr. Carr suffered a 4-10 year history of cognitive decline, with deficits in memory and executive functioning diagnosed by a neuropsychologist. This cognitive decline forced him to end his career as a professor. In 2011 he was diagnosed with possible CTE. According to an article in Vielight, Dr. Carr “suffered daily from unstoppable spontaneous bouts of anger, anxiety, uncontrollable rage and stress that lasted for hours, sometimes, days. These waves were followed by feelings of shame and regret.”
At the Boston VA Medical Center, Naeser gave Carr a battery of baseline tests for depression, PTSD symptoms (emotional outbursts), sleep, memory, and other cognitive functions. Most importantly, Carr was given a functional MRI (fMRI) brain scan, which measures “functional connectivity” between specific areas of the brain cortex.
The results of these baseline tests reflected Carr’s self-reported symptoms. Carr was then given in-office photobiomodulation therapy using MedX Health devices. These are 2-inch diameter, LED cluster heads containing red and near-infrared diodes. He received in-office light therapy three times a week for six weeks; each session lasted 40 minutes.
Subsequently, follow-up test results for emotional outbursts (PTSD), depression, executive function, and verbal learning (including verbal memory) showed significant improvement. The fMRI brain scans showed increased connectivity between brain regions. Dr. Carr reported feeling that he felt like himself, for the first time in years.
Intriguingly, and in line with some previous photobiomodulation research with dementia and Alzheimer’s Disease, Dr. Carr regressed considerably when the study required him to take eight weeks off from photobiomodulation therapy. This regression appeared in his subjective reporting (more emotional outbursts and depressed mood), and in objective test scores for executive function and verbal memory, as well as in his brain fMRI scans, which showed reduced “functional connectivity.”
Noting his resurgent symptoms, Dr. Carr bought his own photobiomodulation devices from Vielight. He purchased the Vielight Neuro Gamma (near-infrared diodes pulsed at 40 Hz), and the Vielight 633 Red intranasal device. His schedule for the Neuro Gamma was M, W, F, with 48 hours between the treatments, and the 633 Red intranasal six days a week. After three months of using his in-home LED devices, he found his mood improving again.
Vielight Neuro Gamma — for more information about this device, see our page on light therapy.
Dr. Carr went back to Dr. Naeser, asking her to repeat the battery of tests, including the “functional connectivity” MRI brain scans. Naeser had not planned for an additional round of MRI brain scans and testing, but she acquired permission to do so.
Dr. Naeser found improvement in all the testing categories, including symptoms of PTSD, depression, executive function, and verbal memory, as well as sleep quality. There was also improvement in “functional connectivity” on the brain scans, especially in the left side of the brain (left hemisphere). Dr. Carr gives a detailed description of his light therapy treatment results in a blog post on his website. You can also read our blog post, an Interview about light therapy with Dr. Larry Carr.
Click on any of the slides below to enlarge.
For more information about selecting and using Vielight devices, see our Light Therapy page. The MedX device used for Dr. Carr’s In-office treatment must be purchased through a clinician; we have more information on this device on our Light Therapy page as well.
We recommend reading Larry Carr’s description of his experience, and his wife Laurie Carr’s viewpoint, at their website FootballandtheBrain.com.
Case Study #2 - retired pro football player (NFL)
The second case study was of a man who had played football in high school, college, and was a cornerback in the NFL from 1983 to 1991. He had repetitive head injuries, with and estimated thousands of subconcussive hits. At age 57 and with a college degree, when he entered the case study, he tested two standard deviations below average on a neuropsychological test.
He was treated in Dr. Naeser’s office, with the Thor Helmet photobiomodulation device, which has red and near-infrared LED lights lining the inside of the helmet. He showed the same kind of positive benefits from photobiomodulation when tested at one week and one month after the final, 18th LED treatment. This individual chose not to have brain MRI scans due to chronic pain.
In addition to neurocognitive and emotional difficulties, this man had suffered through 15 surgeries related to football injuries. At the beginning of the case study, he had chronic shoulder pain and was on three pain medications, two of which were narcotics. After the in-office treatment series light therapy treatment, his pain was reduced, and he was able to discontinue the two narcotic pain medications. There was also a reduction in his tinnitus, from a level of moderate to only mild, after the in-office light therapy treatment series.
Dr. Naeser’s study called for a final series of testing at two months after the cessation of in-clinic light therapy. Concerned about losing his improved health, the man chose to drop out of the study rather than go for two months without light therapy. His comment at that time was, “I don’t want to go back to where I was before I came here. I need to have continued photobiomodulation treatments.”
He then purchased his own Vielight Neuro Gamma device, the same the first football player has for in-home light therapy treatments. His anecdotal reports to Dr. Naeser’s office are that he continues to do well with his at-home LED treatments, now ongoing for ten months.
How did the two case studies differ?
The case studies of the men took different trajectories. Both men improved dramatically with in-clinic light therapy. After the six weeks of in-clinic treatment, the study called for testing at one week, one month, and two months following the end of light therapy treatment.
For Dr. Carr (case study #1), he found that his symptoms had returned at full force after two months without light therapy treatment, and tests confirmed this. He then started using the Vielight Neuro Gamma at home, and after 12 weeks, his symptoms abated. Clinical tests and an fMRI scan confirmed the positive results from the in-home treatment.
In her scientific poster, Naeser discusses potential reasons why the first football player showed regression after discontinuing the photobiomodulation treatments for eight weeks after the final, 18th in-office treatment. This is a pattern also seen with dementia patients who have a progressive neurodegenerative disease, likely Alzheimer’s Disease (Saltmarche, Naeser et al., 2017, Photomedicine and Laser Surgery).
The man in case study #2 was unwilling to without light therapy treatment long enough to be tested at the 2-month point after in-clinic treatment. He feared that his symptoms would return and didn’t want to risk losing the gains that he had made. He dropped out of the study and purchased the Vielight Neuro Gamma device for in-home use. Dr. Naeser has heard that he continues to do in-home light therapy treatments and is doing well.
In different research studies, TBI cases (without repetitive head impacts) continue to maintain gains after completing photobiomodulation treatments (Naeser, Zafonte et al., 2014, Journal of Neurotrauma). They did not have an ongoing progressive neurodegenerative disease.
Current clinical trial recruiting study participants
Dr. Paula Martin, an associate of Dr. Naeser’s, is currently recruiting for a study of photobiomodulation for patients with mild to moderate traumatic closed-head, traumatic brain injury. For this remote study, the researchers are shipping the Vielight Neuro Alpha device (pulsed at 10 Hz) to be used as an at-home treatment. The study is controlled, meaning that all participants will receive the real treatment for several weeks, and a sham treatment for several weeks, without the researchers or participants knowing which treatment is real and which is sham.
For more information and to apply to be a study participant, read, Recruiting for clinical trials: light therapy for persistent concussion symptoms.
Conclusion
The results of these case studies are hopeful, keeping in mind the inherent limitations of case studies – i.e., small sample size, and no control for the placebo effect.
While researchers including Dr. Naeser are urging for further research, the potential for this new therapy is promising. Additional research is being considered for biological research into the mechanisms by which light induces these functional connectivity changes in the brain. Continuing research will also address which modalities of light therapy have the best therapeutic efficacy for acute (recent) and chronic (long-term) brain injury symptoms.
Acknowledgments and Disclaimer
We thank Margaret Naeser, PhD for assistance with editing parts of this article.
This article is for information purposes only. No medical claims are made. By providing the information contained herein, we are not diagnosing, treating, curing, mitigating, or preventing any disease or medical condition. Before beginning treatment regimen, it is advisable to the seek advice of a licensed healthcare professional.
The Vielight devices fit within the FDA category of “Low-Risk Devices, General Wellness;” and no medical claims are made in this category.
Conflict of Interest Disclosure: Vielight, Inc., Toronto, funds some of Professor Naeser's transcranial LED research with traumatic Brain Injury (TBI). The materials presented here do not represent the views of the Department of Veterans Affairs or Boston University School of Medicine. Professor Naeser has no personal, financial conflict of interest to declare.
Related info from our blog
In an interview, RJ discusses his potential CTE and his positive experience as a participant in a University of Utah photobiomodulation (light therapy) study. RJ played high school and college football, experiencing repetitive head impacts and multiple concussions.