title: Spontaneous resolution of traumatic acute subdural haematomas: A systematic review.
abstract: BACKGROUND
  Traumatic subdural haematomas often require emergency surgical evacuation. Spontaneous resolution of traumatic acute subdural haematomas (TASDH) is under-reported. Two patients are described with spontaneous resolution of TASDH correlating with previous reports. A discussion is presented on the clinical, pathological and radiological features of TASDH.
  
  
  METHODS
  A review of the literature was performed using PubMed (Medline), Embase, and Cochrane Library for similar cases.
  
  
  RESULTS
  A total 21 articles were included, involving 27 cases well detailed of TASDH with spontaneous resolution or neurological and radiological improvement in less than 24 h.
  
  
  CONCLUSIONS
  There are two main mechanisms for the spontaneous resolution of acute subdural haematomas: dilution in subarachnoid space and redistribution of the haematoma in the subdural space. The primary radiological characteristic of these lesions is a hypodense rim on the outer surface of the clot. Spontaneous resolution of TASDH is unusual. Clinical and radiological surveillance is essential for appropriate management of these patients.
authors.affiliation: Botucatu Medical School; UNESP Univ Estadual Paulista; Department of Neurology, Psychology and Psychiatry, Botucatu, SP, Brazil. Electronic address: roberto_vital@hotmail.com.
authors.forename: Roberto Bezerra
authors.initials: RB
authors.lastname: Vital
authors.affiliation: Botucatu Medical School; UNESP Univ Estadual Paulista; Department of Neurology, Psychology and Psychiatry, Botucatu, SP, Brazil.
authors.forename: Pedro Tadao
authors.initials: PT
authors.lastname: Hamamoto Filho
authors.affiliation: Botucatu Medical School; UNESP Univ Estadual Paulista; Department of Neurology, Psychology and Psychiatry, Botucatu, SP, Brazil.
authors.forename: Victor Azevedo de
authors.initials: VA
authors.lastname: Oliveira
authors.affiliation: Botucatu Medical School; UNESP Univ Estadual Paulista; Department of Neurology, Psychology and Psychiatry, Botucatu, SP, Brazil.
authors.forename: Flávio Ramalho
authors.initials: FR
authors.lastname: Romero
authors.affiliation: Botucatu Medical School; UNESP Univ Estadual Paulista; Department of Neurology, Psychology and Psychiatry, Botucatu, SP, Brazil.
authors.forename: Marco Antônio
authors.initials: MA
authors.lastname: Zanini
mesh_terms: D000328:Adult; D001930:Brain Injuries / Q000150:complications; D005260:Female; D020199:Hematoma, Subdural, Acute / Q000175:diagnosis / Q000209:etiology; D006801:Humans; D012075:Remission, Spontaneous; D055815:Young Adult
keywords: Brain haemorrhage; Hematoma subdural; Hemorragia cerebral; Subdural haematoma; Traumatic brain injury; Traumatismo craneal