title: Quantitative computer tomography analysis of post-operative subdural fluid volume predicts recurrence of chronic subdural haematoma.
abstract: BACKGROUND
  Post-operative volume of subdural fluid is considered to correlate with recurrence in chronic subdural haematoma (CSDH). Information on the applications of computer-assisted volumetric analysis in patients with CSDHs is lacking.
  
  
  OBJECTIVE
  To investigate the relationship between haematoma recurrence and longitudinal changes in subdural fluid volume using CT volumetric analysis.
  
  
  METHODS
  Fifty-four patients harbouring 64 CSDHs were studied prospectively. The association between recurrence rate and CT findings were investigated.
  
  
  RESULTS
  Eleven patients (20.4%) experienced post-operative recurrence. Higher pre-operative (over 120 ml) and/or pre-discharge subdural fluid volumes (over 22 ml) were significantly associated with recurrence; the probability of non-recurrence for values below these thresholds were 92.7% and 95.2%, respectively. CSDHs with larger pre-operative (over 15.1 mm) and/or residual (over 11.7 mm) widths also had significantly increased recurrence rates. Bilateral CSDHs were not found to be more likely to recur in this series. On receiver-operating characteristic curve, the areas under curve for the magnitude of changes in subdural fluid volume were greater than a single time-point measure of either width or volume of the subdural fluid cavity.
  
  
  CONCLUSIONS
  Close imaging follow-up is important for CSDH patients for recurrence prediction. Using quantitative CT volumetric analysis, strong evidence was provided that changes in the residual fluid volume during the 'self-resolution' period can be used as significantly radiological predictors of recurrence.
authors.affiliation: Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University , Beijing , PR China .
authors.forename: Fei-Fan
authors.initials: FF
authors.lastname: Xu
authors.forename: Jin-Hong
authors.initials: JH
authors.lastname: Chen
authors.forename: Gilberto Ka Kit
authors.initials: GK
authors.lastname: Leung
authors.forename: Shu-Yu
authors.initials: SY
authors.lastname: Hao
authors.forename: Long
authors.initials: L
authors.lastname: Xu
authors.forename: Zong-Gang
authors.initials: ZG
authors.lastname: Hou
authors.forename: Xiang
authors.initials: X
authors.lastname: Mao
authors.forename: Guang-Zhi
authors.initials: GZ
authors.lastname: Shi
authors.forename: Jing-Sheng
authors.initials: JS
authors.lastname: Li
authors.forename: Bai-Yun
authors.initials: BY
authors.lastname: Liu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D056424:Decompressive Craniectomy; D005260:Female; D005500:Follow-Up Studies; D020200:Hematoma, Subdural, Chronic / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000517:prevention & control; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D011184:Postoperative Period; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012008:Recurrence; D018570:Risk Assessment; D013355:Subdural Space / Q000000981:diagnostic imaging / Q000473:pathology; D014057:Tomography, X-Ray Computed
keywords: Chronic subdural haematoma; computer tomography; computer-assisted volumetric analysis; outcome; recurrence