Perfusion neuroimaging using SPECT can detect abnormalities in the brains of retired and current National Football League players, distinguishing them from healthy control subjects, according to results of a new study published online in the Journal of Alzheimer's Disease.
As more neurological research is conducted and more study results continue to be released, the evidence of long-term physical and cognitive effects of repeated head injuries associated with playing football continues to mount.
But exactly where and how these changes take place in the brain—and how to distinguish them—is still under investigation, said lead author Daniel G. Amen of Amen Clinics in Costa Mesa, Calif., and his colleagues.
“Increasing awareness of the adverse long-term effects of repetitive head trauma has raised substantial concern among players, medical professionals, and the general public,” they wrote. “Currently, there is a relative lack of data on what regions are neurophysiologically impaired in living NFL players compared to healthy controls; how well these brain abnormalities distinguish possible repetitive concussive and subconcussive pathology in NFL players from healthy individuals; and what specific brain areas are most predictive of such a classification.”
Amen and his team set out to evaluate the performance of SPECT low perfusion neuroimaging in specific brain regions to distinguish NFL players from normal control subjects. They recruited 161 retired and current NFL players as well as a healthy control group of 124 participants and assessed both groups with medical examinations, neuropsychological tests and SPECT perfusion neuroimaging.
Their results showed that NFL players exhibited lower cerebral perfusion in 36 brain regions on average, with SPECT neuroimaging successfully distinguishing players from the control group with 90 percent sensitivity, 86 percent specificity and 94 percent accuracy.
“Specific brain regions commonly damaged in traumatic brain injury show abnormally low perfusion on SPECT in professional NFL players. These same regions alone can distinguish this group from healthy subjects with high diagnostic accuracy,” the authors concluded. “It is becoming increasingly suggestive that playing football at the professional level is associated with brain abnormalities in players. Longitudinal studies are required at the pre-teen, high school, and college level to better characterize the time course of such alternations.”