title: Predicting recurrence after chronic subdural haematoma drainage.
abstract: BACKGROUND
  Recurrence of chronic subdural haematomas (CSDHs) after surgical drainage is a significant problem with rates up to 20%. This study focuses on determining factors predictive of haematoma recurrence and presents a scoring system stratifying recurrence risk for individual patients.
  
  
  METHODS
  Between the years 2005 and 2009, 331 consecutive patients with CSDHs treated with surgery were included in this study. Univariate and multivariate analyses were performed searching for risk factors of increased post-operative haematoma volume and haematoma recurrence requiring repeat drainage.
  
  
  RESULTS
  We found a 12% reoperation rate. CSDH septation (seen on computed tomogram scan) was found to be an independent risk factor for recurrence requiring reoperation (p=0.04). Larger post-operative subdural haematoma volume was also significantly associated with requiring a second drainage procedure (p<0.001). Independent risk factors of larger post-operative haematoma volume included septations within a CSDH (p<0.01), increased pre-operative haematoma volume (p<0.01), and a greater amount of parenchymal atrophy (p=0.04). A simple scoring system for quantifying recurrence risk was created and validated based on patient age (< or ≥ 80 years), haematoma volume (< or ≥ 160 cc), and presence of septations within the subdural collection (yes or no).
  
  
  CONCLUSIONS
  Septations within CSDHs are associated with larger post-operative residual haematoma collections requiring repeat drainage. When septations are clearly visible within a CSDH, craniotomy might be more suitable as a primary procedure as it allows greater access to a septated subdural collection. Our proposed scoring system combining haematoma volume, age, and presence of septations might be useful in identifying patients at higher risk for recurrence.
authors.affiliation: Division of Neurosurgery,Department of Surgery,University of Alberta,- Edmonton,Alberta,Canada.
authors.forename: Andrew
authors.initials: A
authors.lastname: Jack
authors.affiliation: Division of Neurosurgery,Department of Surgery,University of Alberta,- Edmonton,Alberta,Canada.
authors.forename: Cian
authors.initials: C
authors.lastname: O'Kelly
authors.affiliation: Division of Neurosurgery,Department of Surgery,University of Alberta,- Edmonton,Alberta,Canada.
authors.forename: Cameron
authors.initials: C
authors.lastname: McDougall
authors.affiliation: Division of Neurosurgery,Department of Surgery,University of Alberta,- Edmonton,Alberta,Canada.
authors.forename: J Max
authors.initials: JM
authors.lastname: Findlay
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003399:Craniotomy; D004322:Drainage / Q000379:methods*; D005260:Female; D020200:Hematoma, Subdural, Chronic / Q000175:diagnosis / Q000453:epidemiology* / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D012008:Recurrence; D012189:Retrospective Studies; D012307:Risk Factors; D014057:Tomography, X-Ray Computed
keywords: scoring scale