title: Late presentations of minor head injury.
abstract: OBJECTIVE
  To determine the frequency with which a CT head is performed in patients presenting more than 4 h after minor head injury and the clinical features that predict an abnormal scan.
  
  
  METHODS
  Observational cohort study.
  
  
  METHODS
  Emergency department (ED) of the Royal London Hospital, London, UK.
  
  
  METHODS
  500 patients presenting to the ED of the Royal London Hospital.
  
  
  METHODS
  Chart review of all patients with minor head injury presenting more than 4 h from insult to the ED between December 2007 and May 2009. Inclusion criteria were: age over 16 years, Glasgow coma scale (GCS) 14 or 15 on first assessment, over 4 h post-injury. Exclusion criteria were: age under 16 years, GCS 13 and less, injuries limited to the face with no risk of intracranial injury; presentation less than 4 h after injury.
  
  
  RESULTS
  497 patients were identified: 147 patients had CT head; 11 had intracranial injuries on CT. Loss of consciousness (p=0.0005), potential coagulopathy (p=0.0015), injuries above the clavicles (p=0.0150), open/depressed skull fracture (p=0.0221), alcohol/drug intoxication (p=0.0406) and focal neurology (p=0.0562) were predictors of positive CT scan. Five patients (1% of sample, 45% of patients with abnormal CT) required a neurosurgical procedure. Two (18.2%) self-discharged and four (36.4%) were followed up as outpatients. One patient (0.09%) died as a result of intracranial injury.
  
  
  CONCLUSIONS
  Patients with minor head injury who present over 4 h post-insult exhibit a similar risk of intracranial pathology to those presenting within 4 h. The risk factors previously identified to predict intracranial injury are similar in this study.
authors.affiliation: Emergency Department, The Royal London Hospital, London E1 1BB, UK. annarachelbarrow@hotmail.com
authors.forename: Anna
authors.initials: A
authors.lastname: Barrow
authors.forename: John
authors.initials: J
authors.lastname: Ndikum
authors.forename: Tim
authors.initials: T
authors.lastname: Harris
mesh_terms: D000328:Adult; D015331:Cohort Studies; D006259:Craniocerebral Trauma / Q000175:diagnosis / Q000000981:diagnostic imaging*; D057210:Delayed Diagnosis; D004636:Emergency Service, Hospital; D015600:Glasgow Coma Scale; D006801:Humans; D011237:Predictive Value of Tests; D012307:Risk Factors; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D006113:United Kingdom