title: Twist-Drill or Burr Hole Craniostomy for Draining Chronic Subdural Hematomas: How to Choose It for Chronic Subdural Hematoma Drainage.
abstract: OBJECTIVE
  Although twist-drill craniostomy (TDC) has a number of procedural advantages and an equivalent outcome compared to burr hole craniostomy (BHC) for the treatment of chronic subdural hematomas (CSDHs), the latter technique remains the preferred method. We analyzed symptomatic CSDHs in whom TDC at the pre-coronal suture entry point (PCSEP) was the primary method for hematoma drainage and BHC on the parietal was the secondary option.
  
  
  METHODS
  CSDHs in 86 consecutive patients were included. TDC at the PCSEP, which is 1 cm anterior to coronal suture at the level of the superior temporal line, was the primary operational technique when the hematoma thickness was suitable, and BHC was performed via the parietal when TDC was unreasonable or failed. The clinical feasibility and outcomes of these approaches were analyzed.
  
  
  RESULTS
  Of the 86 patients, 68 (79.1%) were treated by TDC, and 18 (20.9%) by BHC. All patients showed improvements in their symptoms after hematoma drainage. Neither morbidity nor mortality was associated with either technique, and there were no differences in drainage days between the groups. Ten patients had bilateral hematomas and were treated using TDC. Two patients were not sufficiently treated by TDC and, as a result, BHC was applied. Only six hematomas (7% of 86 hematomas) exhibited insufficient thickness on the computed tomography to perform TDC.
  
  
  CONCLUSIONS
  When the hematoma was thick enough, a majority of the CSDHs were drained using TDC at the PCSEP as the first procedure, which was especially useful for bilateral hematomas and in elderly patients.
authors.affiliation: Department of Neurosurgery, Soonchunhyang University Bucheon Hospital, Bucheon, Korea.
authors.forename: Seong-Jong
authors.initials: SJ
authors.lastname: Lee
authors.affiliation: Department of Neurosurgery, Soonchunhyang University Bucheon Hospital, Bucheon, Korea.
authors.forename: Sun-Chul
authors.initials: SC
authors.lastname: Hwang
authors.affiliation: Department of Neurosurgery, Soonchunhyang University Bucheon Hospital, Bucheon, Korea.
authors.forename: Soo Bin
authors.initials: SB
authors.lastname: Im
keywords: Burr hole craniostomy; Chronic subdural hematoma; Hematoma drainage; Twist-drill craniostomy