title: Volume and densities of chronic subdural haematoma obtained from CT imaging as predictors of postoperative recurrence: a prospective study of 107 operated patients.
abstract: BACKGROUND
  Chronic subdural haematoma (CSDH) is a common entity in neurosurgery with a considerable postoperative recurrence rate. Computerised tomography (CT) scanning remains the most important diagnostic test for this disorder. The aim of this study was to characterise the relationship between the recurrence of CSDH after treatment with burr-hole irrigation and closed-system drainage technique and CT scan features of these lesions to assess whether CT findings can be used to predict recurrence.
  
  
  METHODS
  We investigated preoperative and postoperative CT scan features and recurrence rate of 107 consecutive adult surgical cases of CSDH and assessed any relationship with univariate and multivariate regression analyses.
  
  
  RESULTS
  Seventeen patients (15.9 %) experienced recurrence of CSDH. The preoperative haematoma volume, the isodense, hyperdense, laminar and separated CT densities and the residual total haematoma cavity volume on the 1st postoperative day after removal of the drainage were identified as radiological predictors of recurrence. If the preoperative haematoma volume was under 115 ml and the residual total haematoma cavity volume postoperatively was under 80 ml, the probability of no recurrence was very high (94.4 % and 97.4 % respectively).
  
  
  CONCLUSIONS
  These findings from CT imaging may help to identify patients at risk for postoperative recurrence.
authors.affiliation: Department of Neurosurgery, Oslo University Hospital, Nydalen, Po. Box 4950, 0424, Oslo, Norway. mstanisi@ous-hf.no
authors.forename: Milo
authors.initials: M
authors.lastname: Stanišić
authors.forename: John
authors.initials: J
authors.lastname: Hald
authors.forename: Inge Andre
authors.initials: IA
authors.lastname: Rasmussen
authors.forename: Are Hugo
authors.initials: AH
authors.lastname: Pripp
authors.forename: Jugoslav
authors.initials: J
authors.lastname: Ivanović
authors.forename: Frode
authors.initials: F
authors.lastname: Kolstad
authors.forename: Jarle
authors.initials: J
authors.lastname: Sundseth
authors.forename: Mark
authors.initials: M
authors.lastname: Züchner
authors.forename: Karl-Fredrik
authors.initials: KF
authors.lastname: Lindegaard
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003399:Craniotomy; D004322:Drainage; D005260:Female; D020200:Hematoma, Subdural, Chronic / Q000175:diagnosis* / Q000209:etiology / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012008:Recurrence; D012044:Regression Analysis; D018570:Risk Assessment; D007507:Therapeutic Irrigation; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome