Neurology:  Post-Concussion Syndrome
                ------------------------------------

þ Never causes focal neurological deficit.

þ symptoms:
 - headache
 - memory loss
 - dizzyness/vertigo
 - diplopia (?)
 - blurred vision
 - emotional lability
 - sleep disturbances

þ usually a few weeks, but may last months or years.

 - after minor head injury, may have persistent problems (e.g., headache) for
   up to 3 months.  [Rimel et al. Neurosurgery 1981;9:271-228.]
 - 45% incidence in neurosurgery literature (but this is only on patients on
   whom neurosurgery was consulted, so doesn't represent the full ED population
   with head injury, where the incidence is much lower).  Cliff Callaway (Pitt
   EM Resident) is working on research to find the true incidence (1995).