High-field MRI reveals previously undetectable injuries in developing brain

November 9, 2011
Highfield MRI

High-field MRI at 12 Tesla (12T) is markedly more sensitive in detecting early white-matter injury --- broad dark black area (arrow) --- than is lower field MRI at 3 Tesla (3T) (credit: OHSU)

Pediatric neuroscientists at Oregon Health & Science University Doernbecher Children’s Hospital are the first to use high magnetic field strength (12 Tesla), MRI to reveal tiny white matter injuries in the developing brain previously undetectable using standard (3T) MRI.

Early, accurate identification of these lesions in the preterm human infant could prevent delays in therapy and enable physicians to inform families sooner of the potential for complications, including inability to walk and intellectual challenges.

White-matter injury is the most common cause of chronic neurologic disability in children with cerebral palsy, explains principal investigator Stephen Back, M.D., Ph.D., but babies with cerebral palsy often have MRIs that miss injury, which creates significant challenges, including delayed treatment intervention and rehabilitation.

White matter injury occurs during brain development when nerve fibers are actively being wrapped in myelin, the insulation that allows nerve fibers to rapidly transmit signals in the brain. The cells required to make myelin can be easily destroyed when blood flow to the developing brain falls below normal or when maternal infection occurs during pregnancy. The loss of these cells disrupts brain maturation and results in failure to make the myelin required for normal brain function.

In this study, using high-field MRI (12-Tesla), Back and colleagues were able to identify tiny brain lesions in preterm fetal sheep with characteristics previously unseen and unreported using a standard 3-T MRI.

Future studies are needed to determine if lower field MRI scanners, that are used for patients, can be adapted to achieve greater sensitivity to detect early injury to the white matter of the premature human infant, the researchers said.

Ref.: Art Riddle, et al., Histopathological correlates of magnetic resonance imaging–defined chronic perinatal white matter injury, Annals of Neurology, 2011; [DOI: 10.1002/ana.22501]