title: One vs. Two Burr Hole Craniostomy in Surgical Treatment of Chronic Subdural Hematoma.
abstract: OBJECTIVE
  Chronic subdural hematoma (CSDH) is one of the most common types of traumatic intracranial hemorrhage, usually occurring in the older patients, with a good surgical prognosis. Burr hole craniostomy is the most frequently used neurosurgical treatment of CSDH. However, there have been only few studies to assess the role of the number of burr holes in respect to recurrence rates. The aim of this study is to compare the postoperative recurrence rates between one and two burr craniostomy with closed-system drainage for CSDH.
  
  
  METHODS
  From January 2002 to December 2006, 180 consecutive patients who were treated with burr hole craniostomy with closed-system drainage for the symptomatic CSDH were enrolled. Pre- and post-operative computed tomography (CT) scans and/or magnetic resonance imaging (MRI) were used for radiological evaluation. The number of burr hole was decided by neurosurgeon's preference and was usually made on the maximum width of hematoma. The patients were followed with clinical symptoms or signs and CT scans. All the drainage catheters were maintained below the head level and removed after CT scans showing satisfactory evacuation. All patients were followed-up for at least 1 month after discharge.
  
  
  RESULTS
  Out of 180 patients, 51 patients were treated with one burr hole, whereas 129 were treated with two burr holes. The overall postoperative recurrence rate was 5.6% (n = 10/180) in our study. One of 51 patients (2.0%) operated on with one burr hole recurred, whereas 9 of 129 patients (7.0%) evacuated by two burr holes recurred. Although the number of burr hole in this study is not statistically associated with postoperative recurrence rate (p > 0.05), CSDH treated with two burr holes showed somewhat higher recurrence rates.
  
  
  CONCLUSIONS
  In agreement with previous studies, burr hole craniostomy with closed drainage achieved a good surgical prognosis as a treatment of CSDH in this study. Results of our study indicate that burr hole craniostomy with one burr hole would be sufficient to evacuate CSDH with lower recurrence rate.
authors.affiliation: Department of Neurosurgery, Gachon University of Medicine and Science, Gil Medical Center, Incheon, Korea.
authors.forename: Hong-Joon
authors.initials: HJ
authors.lastname: Han
authors.forename: Cheol-Wan
authors.initials: CW
authors.lastname: Park
authors.forename: Eun-Young
authors.initials: EY
authors.lastname: Kim
authors.forename: Chan-Jong
authors.initials: CJ
authors.lastname: Yoo
authors.forename: Young-Bo
authors.initials: YB
authors.lastname: Kim
authors.forename: Woo-Kyung
authors.initials: WK
authors.lastname: Kim