Complex Pathophysiology of Abusive Head Trauma with Poor Neurological Outcome in Infants

Abusive head trauma (AHT) in infants, especially acute subdural hematoma, has an extremely poor outcome. The most decisive and important finding is the appearance of a widespread low-density area on head computed tomography. This phenomenon was traditionally thought to be caused by cerebral ischemia. However, many other pathophysiological abnormalities have been found to be intricately involved. Recent studies have found that status epilepticus and hyperperfusion injures are the major causes. Another serious problem associated with AHT is cardiopulmonary arrest (CPA). Many infants are reported to visit to the hospital with CPA, and its pathophysiology has not been fully elucidated. This paper examines the background of these pathological conditions and associated factors and elucidate the pathophysiological mechanisms resulting in poor outcomes in AHT. In addition to the intensity of assault on the head, the peculiar pathophysiological characteristics in infants, as well as the social background specific to child abuse, are found to be associated with poor outcome.