MRI Measurements Will Track Brain Development in Children in NIH-Sponsored Study at The Children's Hospital of Philadelphia

The study’s goal is to establish standard anatomical measurements of normal, developing brain structures, and to correlate those measures with the development of cognitive and behavioral skills. Scientists know about the normal development of motor skills, but need to know more about normal brain development. The brain changes quickly during the first five years of life, and the study will help establish a normal growth curve for the brain.

Children in two major age groups will be studied: infants and preschoolers (up to age four), and children and adolescents (ages five to 18). Children’s Hospital will study 50 to 60 children among the total of 500 for the entire multicenter project. In order to study changes over time, all but the oldest children will be followed over a five-year period.

"This study will produce a standardized sample for MRI and neuropsychology studies for decades to come," says physicist John C. Haselgrove, Ph.D., director of the Magnetic Resonance Research Facility at Children’s Hospital and principal investigator of the grant.

The children will be assessed with a battery of behavioral, language, motor skills and cognitive tests that will be correlated with the MRI findings. Having systematic data from normal, healthy children will provide a basis for comparison to children with developmental or neurologic problems. For example, doctors will be better able understand reading problems. If they can compare MRI scans from children with reading problems to scans from children who read normally, they might determine whether reading problems are associated with differences in brain structure. Similarly, they can study brain development in relation to memory skills. Memory has been studied more often in disease states than in normal, healthy subjects.

Studies of other disorders, such as autism or attention deficit-hyperactivity disorder, might also be advanced with the database.

MRI has been used clinically since late 1970s, but only in the past few years have medical institutions moved toward standardizing the equipment they use. MRI is safe and noninvasive; it requires placing a person in a strong magnetic field and measuring the response of nuclei inside the body’s molecules. Different tissues respond differently, and computer software processes the magnetic signals into sharp, three-dimensional images of internal structures.

A related technology, magnetic resonance spectroscopy (MRS), sorts out different metabolites – biological chemicals normally processed in the brain. "We already know that tumors or metabolic diseases show distinctive signatures detectable by MRS," says Dr. Haselgrove. Some of the children to be studied at Children’s Hospital will also be examined by MRS to provide normal data on brain metabolites.

Although the procedure is noninvasive, a person must lie motionless for eight to 10 minutes while the MRI machine scans the brain. For babies, the test will be performed as they sleep. Children up to age 7 who will be awake during the procedure will first be familiarized with the eq