title: Surgery for Acute Subdural Hematoma: Replace or Remove the Bone Flap?
abstract: OBJECTIVE
  In surgery for acute subdural hematoma (ASDH), the bone flap can be fixed onto the skull, left riding to provide partial skull decompression, or removed. This study assessed whether removing the bone flap improved outcome.
  
  
  METHODS
  We conducted an observational study on consecutive patients who were operated for ASDH in our hospital from July 2011 to June 2014. We retrospectively collected data on demographics, injury severity, and predicted and observed outcomes at 6 months. The cohort was divided into 2 groups based on whether the bone flap was replaced (fixed and riding flap craniotomy) or removed (decompressive craniectomy). The differences in functional status, postoperative control of intracranial hypertension, and number of cranial reoperations were analyzed. A subgroup analysis compared decompressive craniectomy with riding flap craniotomy alone.
  
  
  RESULTS
  Data were obtained for 99 patients; 69 had decompressive craniectomy, 17 had riding flap craniotomy, and 13 had fixed flap craniotomy. The decompressive craniectomy group had statistically worse injuries, more predicted poor outcomes (69% vs. 57%, P = 0.013), more observed poor outcomes (59% vs. 37%, P = 0.037), equivalent control of intracranial hypertension, and a similar number of reoperations compared with the craniotomy groups. Subgroup analysis between decompressive craniectomy and riding flap craniotomy showed no significant difference in baseline characteristics and outcomes.
  
  
  CONCLUSIONS
  Our study concluded that removing the bone flap after ASDH evacuation was not associated with a better outcome. We recommend replacing the bone flap if brain conditions allow. Further research is required to evaluate the role of skull decompression in surgery for ASDH.
authors.affiliation: Department of Neurosurgery, Queen Elizabeth Hospital, Birmingham, UK. Electronic address: georgios.tsermoulas@nhs.net.
authors.forename: Georgios
authors.initials: G
authors.lastname: Tsermoulas
authors.affiliation: Department of Neurosurgery, Queen Elizabeth Hospital, Birmingham, UK.
authors.forename: Omid
authors.initials: O
authors.lastname: Shah
authors.affiliation: Department of Neurosurgery, Queen Elizabeth Hospital, Birmingham, UK.
authors.forename: Haren Eranga
authors.initials: HE
authors.lastname: Wijesinghe
authors.affiliation: Department of Neurosurgery, Queen Elizabeth Hospital, Birmingham, UK.
authors.forename: Adikarige Haritha Dulanka
authors.initials: AHD
authors.lastname: Silva
authors.affiliation: Department of Neuroradiology, Queen Elizabeth Hospital, Birmingham, UK.
authors.forename: Satheesh K
authors.initials: SK
authors.lastname: Ramalingam
authors.affiliation: Department of Neurosurgery, Queen Elizabeth Hospital, Birmingham, UK.
authors.forename: Antonio
authors.initials: A
authors.lastname: Belli
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015984:Causality; D015897:Comorbidity; D003399:Craniotomy / Q000401:mortality* / Q000706:statistics & numerical data; D056424:Decompressive Craniectomy / Q000401:mortality* / Q000706:statistics & numerical data; D005260:Female; D020199:Hematoma, Subdural, Acute / Q000401:mortality* / Q000601:surgery*; D006801:Humans; D019586:Intracranial Hypertension / Q000401:mortality* / Q000601:surgery*; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012086:Reoperation; D012307:Risk Factors; D012886:Skull / Q000637:transplantation; D013524:Surgical Flaps / Q000637:transplantation; D015996:Survival Rate; D016896:Treatment Outcome; D006113:United Kingdom / Q000453:epidemiology; D055815:Young Adult
keywords: Acute subdural hematoma; Brain edema; Craniotomy; Decompressive craniectomy; Traumatic brain injury