title: Comparison of accidental and nonaccidental traumatic head injury in children on noncontrast computed tomography.
abstract: OBJECTIVE
  Mixed-density convexity subdural hematoma and interhemispheric subdural hematoma suggest nonaccidental head injury. The purpose of this retrospective observational study is to investigate subdural hematoma on noncontrast computed tomography in infants with nonaccidental head injury and to compare these findings in infants with accidental head trauma for whom the date of injury was known.
  
  
  METHODS
  Two blinded, independent observers retrospectively reviewed computed tomography scans with subdural hematoma performed on the day of presentation on 9 infant victims of nonaccidental head injury (mean age: 6.8 months; range: 1-25 months) and on 38 infants (mean age: 4.8 months; range: newborn to 34 months) with accidental head trauma (birth-related: 19; short fall: 17; motor vehicle accident: 2).
  
  
  RESULTS
  Homogeneous hyperdense subdural hematoma was significantly more common in children with accidental head trauma (28 of 38 [74%]; nonaccidental head trauma: 3 of 9 [33%]), whereas mixed-density subdural hematoma was significantly more common in cases of nonaccidental head injury (6 of 9 [67%]; accidental head trauma: 7 of 38 [18%]). Twenty-two (79%) subdural hematomas were homogeneously hyperdense on noncontrast computed tomography performed within two days of accidental head trauma, one (4%) was homogeneous and isodense compared to brain tissue, one (4%) was homogeneous and hypodense, and four (14%) were mixed-density. There was no statistically significant difference in the proportion of interhemispheric subdural hematoma, epidural hematoma, calvarial fracture, brain contusion, or subarachnoid hemorrhage.
  
  
  CONCLUSIONS
  Homogeneous hyperdense subdural hematoma is more frequent in cases of accidental head trauma; mixed-density subdural hematoma is more frequent in cases of nonaccidental head injury but may be observed within 48 hours of accidental head trauma. Interhemispheric subdural hematoma is not specific for inflicted head injury.
authors.affiliation: Department of Diagnostic Imaging, Rhode Island Hospital, Brown Medical School, 593 Eddy St, Providence, Rhode Island 02903, USA. gtung@lifespan.org
authors.forename: Glenn A
authors.initials: GA
authors.lastname: Tung
authors.forename: Monica
authors.initials: M
authors.lastname: Kumar
authors.forename: Randal C
authors.initials: RC
authors.lastname: Richardson
authors.forename: Carole
authors.initials: C
authors.lastname: Jenny
authors.forename: William D
authors.initials: WD
authors.lastname: Brown
mesh_terms: D000058:Accidental Falls; D000059:Accidents; D000063:Accidents, Traffic; D001720:Birth Injuries / Q000000981:diagnostic imaging; D001930:Brain Injuries / Q000000981:diagnostic imaging / Q000209:etiology; D002649:Child Abuse / Q000175:diagnosis*; D002675:Child, Preschool; D003287:Contrast Media; D006259:Craniocerebral Trauma / Q000150:complications / Q000000981:diagnostic imaging*; D003937:Diagnosis, Differential; D005260:Female; D006408:Hematoma, Subdural / Q000000981:diagnostic imaging / Q000209:etiology*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D012166:Retinal Hemorrhage / Q000209:etiology; D012189:Retrospective Studies; D038642:Shaken Baby Syndrome / Q000000981:diagnostic imaging; D016037:Single-Blind Method; D020204:Skull Fracture, Depressed / Q000000981:diagnostic imaging / Q000209:etiology; D014057:Tomography, X-Ray Computed; D014754:Violence
chemical_list: D003287:Contrast Media