title: Accuracy of external ventricular drainage catheter placement.
abstract: BACKGROUND
  External ventricular drainage (EVD) is a freehand neurosurgical procedure performed routinely using the anatomical landmarks.
  
  
  OBJECTIVE
  The aim of this study was to determine the accuracy of EVD catheter freehand placement.
  
  
  METHODS
  Pre-operative and post-operative computed tomography scans for 66 consecutive EVDs performed in 56 adult patients (26 men, 30 women) in 2008 were retrospectively reviewed. Etiologies of acute hydrocephalus were subarachnoid or intraventricular haemorrhage (43 cases) or miscellaneous (13 cases). Pre-operative lateral ventricular volume, position of the burr hole, length of the catheter and its sagittal and coronal angular variations from a theoretical trajectory were measured.
  
  
  RESULTS
  The EVD was placed on the right (53 cases) or left (13 cases) side. The mean pre-operative lateral ventricular volume was 51 cc (10-118 cc). The average distance from the burr hole to the midline was 28 mm (10-49 mm) and to the supra-orbital ridge was 101 mm (75-125 mm). The mean intracranial catheter length was 60 mm (from 39-102 mm). Only 50% of the EVDs in the coronal plane and 40% in the sagittal plane were placed with an angular variation of ±5° to the target. The tip was placed outside of the ventricles in three cases; 13 catheters crossed the midline, and five intracranial minor haemorrhages were detected.
  
  
  CONCLUSIONS
  Freehand placement of EVDs does not have sufficient accuracy and may lead to drainage dysfunctions. This data suggests that a guidance system for EVD's would be required.
authors: Department of Neurosurgery, University Paris East, Medical School, Assitance Publique - Hôpitaux de Paris, Henri Mondor Hospital, Créteil, France.
authors: Mohammad Ghazi
authors: MG
authors: Abdoh
authors: Olivier
authors: O
authors: Bekaert
authors: Jérôme
authors: J
authors: Hodel
authors: Salia Mamadou
authors: SM
authors: Diarra
authors: Caroline
authors: C
authors: Le Guerinel
authors: Rémi
authors: R
authors: Nseir
authors: Sylvie
authors: S
authors: Bastuji-Garin
authors: Philippe
authors: P
authors: Decq
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002404:Catheterization / Q000009:adverse effects / Q000379:methods / Q000592:standards; D004322:Drainage / Q000009:adverse effects / Q000379:methods / Q000592:standards; D005260:Female; D006801:Humans; D006849:Hydrocephalus / Q000209:etiology / Q000503:physiopathology / Q000601:surgery*; D020547:Lateral Ventricles / Q000033:anatomy & histology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D019635:Neurosurgical Procedures / Q000009:adverse effects / Q000379:methods / Q000592:standards; D011183:Postoperative Complications / Q000209:etiology / Q000503:physiopathology* / Q000517:prevention & control; D012189:Retrospective Studies; D055815:Young Adult