The time course for the development of subdural fluid collections after a single traumatic event in 55 head trauma patients younger than 3 years was determined by CT scan in a retrospective consecutive case series at Children’s Hospital of Wisconsin, Milwaukee. The date of injury could be determined for 55 (64%) of 86 patients with trauma-related subdural fluid collections. The mean age for the 55 patients (33 boys, 22 girls) was 8.4 +/- 13.1 months). The mechanism of injury was intentional trauma in 41 (75%), unintentional trauma in 10 (18%), and uncertain intent in 4 (7%). The initial visualization of subdural fluid in 267 CT examinations occurred during the first week after injury in 44 (80%) of 55 patients. In the remaining 11 patients, the time of origin of subdural fluid was less than 2 weeks for 4 and less than 3 weeks for 6. The location of the fluid was frontal in all but 1 patient (98%). The fluid collection was unilateral in 9 (16%) and bilateral in 46 (84%). Hemorrhage accompanying the subdural effusion was subdural in 48 (87%) patients, epidural in 3 (6%), and subarachnoid in 1 (2%). Eight (15%) patients died within 30 days of injury. Subdural fluid collections persisted for at least 1 month in 10 (18%), spontaneous resolution occurred in 14 (25%), and subdural shunts were placed in 8 (15%). Brain atrophy, with enlarged ventricles and sulci, developed in 16 (48%) of 33 patients followed with CT for at least 2 weeks after injury. [1]

COMMENT. Low attenuation subdural fluid on CT in infants with a history of head injury should raise the suspicion of child abuse. The appearance of subdural fluid most often occurs within a few days of the trauma.

Neuroimaging of intraparenchymal lesions predicted outcome in shaken baby syndrome in 23 children with nonaccidental head injury [2]. A low Glasgow Coma Scale score, retinal hemorrhages, skull fracture, cranial growth deceleration, and brain atrophy on MRI (15 days to 3 months after injury) were significantly associated with poor developmental outcome.

Abusive head injury as a cause of apparent life-threatening events (ALTE) in infancy was diagnosed in 6 (2.5%) of a consecutive series of 243 infants younger than 12 months admitted to Westchester Medical Center, New York Medical College, Valhalla [3]. ALTE is a sudden breathing abnormality, color change, or altered muscle tone or mental status, often requiring emergency resuscitation. Thirty-five different causes of ALTE were identified, and abusive head injury was responsible in 1 admission every 5 months. An ophthalmologic examination revealed retinal hemorrhages leading to a CT scan in 4 of the 6 diagnosed with abusive head injury and focal seizures developed in 1. ALTE is to be distinguished from sudden infant death syndrome.

A distinct cytokine profile identified in SIDS brain could cause disturbed homeostatic control of cardiorespiratory brainstem centers and arousal responses and might represent a common denominator in this multifactorial syndrome [4]. The authors detected high neuronal interleukin (IL)-l [beta] immunoreactivity in the arcuate and dorsal vagal nuclei of SIDS cases.