title: Minimally invasive bedside craniotomy using a self-controlling pre-adjustable mechanical twist drill trephine.
abstract: BACKGROUND
  Craniotomy with a mechanical twist drill is a standard, minimally invasive procedure in neurosurgery, widely used for the drainage of chronic subdural hematomas and the placement of ventricular drains. Nevertheless, the use of a standard twist drill trephine bears the risk of causing cerebral lesions.
  
  
  METHODS
  A commercially available mechanical twist drill system has been modified by a special self-controlling drill and a pre-adjustable distance holder that limits intracerebral penetration. After initial cadaver testing, the modified trephine has been used for 65 trephinations in patients (37 chronic subdural hematomas, 21 external ventricular drains, 6 frontal hygromas, 1 tumor cyst).
  
  
  RESULTS
  There were no complications related to the modified trephine; cerebral lesions caused by drilling too deeply or by uncontrolled penetration were safely prevented. In our series no procedure related infections occurred, and the drilling time was reduced significantly.
  
  
  CONCLUSIONS
  The described modified mechanical twist drill enables fast, easy, and safe craniotomy without jeopardizing the advantages of a mechanical twist drill. Therefore, it can be recommended particularly for difficult emergency conditions.
authors.affiliation: Department of Neurosurgery, Technical University (RWTH) Aachen, Germany.
authors.forename: M H
authors.initials: MH
authors.lastname: Reinges
authors.forename: A
authors.initials: A
authors.lastname: Rübben
authors.forename: U
authors.initials: U
authors.lastname: Spetzger
authors.forename: H
authors.initials: H
authors.lastname: Bertalanffy
authors.forename: J M
authors.initials: JM
authors.lastname: Gilsbach
mesh_terms: D001930:Brain Injuries / Q000209:etiology / Q000517:prevention & control*; D003399:Craniotomy / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D006801:Humans; D019563:Mechanics; D019060:Minimally Invasive Surgical Procedures; D013525:Surgical Instruments; D016896:Treatment Outcome; D014207:Trephining / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods