title: Reduction of Midline Shift Following Decompressive Hemicraniectomy for Malignant Middle Cerebral Artery Infarction.
abstract: OBJECTIVE
  Hemicraniectomy is a decompressive surgery used to remove a large bone flap to allow edematous brain tissue to bulge extracranially. However, early indicators of the decompressive effects of hemicraniectomy are unclear. We investigated whether reduction of midline shift following hemicraniectomy is associated with improved consciousness and survival in patients with malignant middle cerebral artery infarctions.
  
  
  METHODS
  We studied 70 patients with malignant middle cerebral artery infarctions (MMI) who underwent hemicraniectomies. Midline shift was measured preoperatively and postoperatively using computed tomography (CT). Consciousness level was evaluated using the Glasgow Coma Scale on postoperative day 1. Patient survival was assessed six months after stroke onset.
  
  
  RESULTS
  The median time interval between preoperative and postoperative CT was 8.3 hours (interquartile range, 6.1-10.2 hours). Reduction in midline shift was associated with higher postoperative Glasgow Coma Scale scores (P<0.05). Forty-three patients (61.4%) were alive at six months after the stroke. Patients with reductions in midline shifts following hemicraniectomy were more likely to be alive at six months post-stroke than those without (P<0.001). Reduction of midline shift was associated with lower mortality at six months after stroke, after adjusting for age, sex, National Institutes of Health Stroke Scale score, and preoperative midline shift (adjusted hazard ratio, 0.71; 95% confidence interval, 0.62-0.81;P<0.001).
  
  
  CONCLUSIONS
  Reduction in midline shift following hemicraniectomy was associated with improved consciousness and six-month survival in patients with MMI. Hence, it may be an early indicator of effective decompression following hemicraniectomy.
authors.affiliation: Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Sang-Beom
authors.initials: SB
authors.lastname: Jeon
authors.affiliation: Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Sun U
authors.initials: SU
authors.lastname: Kwon
authors.affiliation: Department of Neurosurgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Jung Cheol
authors.initials: JC
authors.lastname: Park
authors.affiliation: Department of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Deok Hee
authors.initials: DH
authors.lastname: Lee
authors.affiliation: Division of Epidemiology and Biostatistics Clinical Research Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Sung-Cheol
authors.initials: SC
authors.lastname: Yun
authors.affiliation: Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Yeon-Jung
authors.initials: YJ
authors.lastname: Kim
authors.affiliation: Department of Neurosurgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Jae-Sung
authors.initials: JS
authors.lastname: Ahn
authors.affiliation: Department of Neurosurgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Byung-Duk
authors.initials: BD
authors.lastname: Kwun
authors.affiliation: Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Dong-Wha
authors.initials: DW
authors.lastname: Kang
authors.affiliation: Departments of Neurology and Neurosurgery, TheUniversity of Texas Medical School at Houston, Houston, Texas, USA.
authors.forename: H Alex
authors.initials: HA
authors.lastname: Choi
authors.affiliation: Departments of Neurology and Neurosurgery, TheUniversity of Texas Medical School at Houston, Houston, Texas, USA.
authors.forename: Kiwon
authors.initials: K
authors.lastname: Lee
authors.affiliation: Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Jong S
authors.initials: JS
authors.lastname: Kim
keywords: Decompressive craniectomy; Infarction; Middle cerebral artery; Mortality