Serial MR, CT Neuroimaging Scanning Helps Identify Timing of Abusive Head Trauma in Infants

Researchers have classified the appearance and development of abnormalities on neuroimages that represent abusive head trauma (AHT) in infants. The researchers’ descriptions of these abnormalities are vital for narrowing down the time frame of AHT, which can aid police in identifying and excluding potential perpetrators.

Appearances of a host of abusive traumatic injuries on cranial computed tomography (CT) and magnetic resonance imaging (MRI) scans at different time points were reported online, ahead of print June 25, 2013, in the Journal of Neurosurgery: Pediatrics. The study conducted by researchers from Pennsylvania State College of Medicine (Penn State; Hershey, USA) and Penn State Milton S. Hershey Medical Center (Hershey, PA, USA) is the largest one on timing of AHT, and its findings validate and extend those of an earlier, smaller study conducted by the senior author, Dr. Mark S. Dias. The researchers hope that this article will serve as an important reference for professionals called upon to provide a time frame for abusive head injuries.

Dr. Bradford and colleagues examined the medical records and imaging studies of all infants (younger than 24 months of age) with abusive head trauma (AHT) who were admitted to Penn State Milton S. Hershey Medical Center between January 1997 and December 2007. The researchers identified 105 infants whose patient charts contained specific injury dates and for whom serial CT scans were available. These infants were chosen for the study population; they ranged in age from 0.3 to 23 months (mean age 5.3 months, median age 3.9 months). More precise timing of injury (time of day) was noted in the charts of 43 of these infants, and MRI scans were available in all children in this subgroup. Serial MRI scanning was not performed in any of these infants.

The researchers studied intracranial abnormalities on the infants’ CT and MRI scans that are signs of a variety of abusive head traumatic injuries. The characteristics of these neuroimaging abnormalities and the timing of their presentations postinjury were detailed and analyzed in the article. Abnormalities indicating epidural hematoma, acute subdural hematoma, subarachnoid hemorrhage, and brain hypodensity appear shortly after injury; abnormalities representative of brain softening and atrophy appear later. All injuries in the subgroup were subdural hematomas.

The most typical injury in the patient group was subdural hematoma (92% of cases). Other frequently found injuries included brain hypodensity (38%), edema (30%), and skull fracture (26%).

Dr. Bradford and colleagues believe that their findings can provide a framework on which physicians can make wide-ranging estimates of the timing of the AHT. They cautioned, however, that neuroimaging findings should not be used alone to make definitive statements about the timing of the original injury. They noted that the patient’s clinical history might suggest a more limited temporal window for the injury than the neuroimaging evidence. The researchers recommended that the neuroimaging findings should be used in combination with the patient’s clinical history to more precisely estimate the timing of injury.

Dr. Dias concluded, “This study will contribute to our understanding of how CT and MRI scans evolve over time following an abusive head injury in an infant and plays an important role in sorting out when abuse occurred. This study allows us to provide ranges within which injury may have occurred, although there are necessary limitations to such a study, and more studies are needed to help pinpoint the time of injury with even greater accuracy.”

Related Links:
Pennsylvania State College of Medicine
Penn State Milton S. Hershey Medical Center