PITTSBURGH, June 18, 2013 – The distribution of white matter brain abnormalities in some patients after mild traumatic brain injury (mTBI) closely resembles that found in early Alzheimer’s, according to a new study published in this month’s Radiology by University of Pittsburgh School of Medicine investigators.
White matter in the brain is made up of long, finger-like fibers projecting from nerve cells and is covered by a whitish fatty material. While gray matter, the part of our brain without the fatty covering, holds our knowledge, white matter is what connects different regions of gray matter, allowing different parts of the brain to communicate with one another.
The study suggests that the initial traumatic event that causes mTBI, or concussion, acts as a trigger for a sequence of degenerative changes in the brain, which result in patient symptoms and are very similar to the degenerative changes seen in early Alzheimer’s. Saeed Fakhran, M.D., assistant professor of radiology at Pitt, and his research team wanted to see if there was a relationship between white matter injury patterns and severity of post-concussion symptoms in mTBI patients with normal findings on conventional magnetic resonance imaging (MRI) exams. The researchers studied data from imaging exams performed on 64 mTBI patients and 15 control patients utilizing an advanced MRI technique called diffusion tensor imaging (DTI), which identifies microscopic changes in the brain’s white matter.
“In the past, we believed that patients with mTBI have symptoms because of abnormalities secondary to the initial injury,” said Dr. Fakhran. “Our preliminary findings suggest that the initial event causing the concussion is like lighting a fuse, acting as a trigger for a sequence of degenerative changes resulting in patient symptoms that could potentially be prevented.”
According to Dr. Fakhran, sleep-wake disturbances (SWD) are among the most debilitating post-concussive symptoms, affecting patients’ quality of life and productivity and magnifying post-concussion memory and social dysfunction. Such disturbances are among the earliest symptoms in Alzheimer’s patients, and also are seen in many mTBI patients. In addition, many mTBI patients have difficulty filtering out white noise and concentrating on important sounds, making it difficult for them to understand the world around them. Hearing problems are an independent risk factor for developing Alzheimer’s disease, and the same type of problem in mTBI patients has predicted which patients with memory problems will eventually develop Alzheimer’s disease.
“For this study, we looked back, analyzing images of injuries. In further research, we hope to recruit patients immediately after their injury and watch brain changes as they occur over time. The first step in developing a treatment for any disease is understanding what causes it, and if we can prove a link, or even a common pathway, between mTBI and Alzheimer’s it could potentially lead to effective treatment strategies for both diseases,” said Dr. Fakhran.