title: Risk factors for recurrence of chronic subdural hematoma after burr hole surgery: potential protective role of dexamethasone.
abstract: OBJECTIVE
  Chronic subdural hematomas (CSDHs) are often found in neurosurgery, and display a recurrence rate of up to 37%. This study aimed to determine potential risk factors contributing to unilateral CSDH recurrence, and evaluate the role of postoperative management with dexamethasone (DX) in reducing recurrence.
  
  
  METHODS
  Between January 2010 and May 2015, a total of 242 consecutive patients with CSDH treated with burr-hole trephination were included in this study. Univariate and multivariate analyses were performed to determine risk factors potentially associated with the recurrence of CSDH. Then, patients at high risk were divided into DX and non-DX treatment groups, respectively. Chi-square test was used to assess the potential role of DX.
  
  
  RESULTS
  CSDH recurrence was recorded in 39 patients (16.1%). Among various risk factors, advanced age (p = .01), preoperative midline displacement exceeding 10 mm (p < .001), and hematomas presenting with separated type (p = .03) were significantly associated with CSDH recurrence. Interestingly, patients who accepted therapy with DX had a lower rate of second drainage procedure (p = .017). In addition, DX effectively reduced disease recurrence in patients with the separated type of hematoma (p = .047), and seemed to be beneficial to those with advanced age and midline shift exceeding 10 mm, although statistical significance was not achieved.
  
  
  CONCLUSIONS
  These findings indicated that advanced age, midline displacement, and mixed density hematoma are independent factors for unilateral CSDH recurrence. When the above factors are detected in patients, additional DX administration should be recommended after operation.
authors.affiliation: a Department of Neurosurgery , Ren Ji Hospital, School of Medicine, Shanghai Jiaotong University , Shanghai , China.
authors.forename: Zhongrun
authors.initials: Z
authors.lastname: Qian
authors.affiliation: a Department of Neurosurgery , Ren Ji Hospital, School of Medicine, Shanghai Jiaotong University , Shanghai , China.
authors.forename: Dianxu
authors.initials: D
authors.lastname: Yang
authors.affiliation: b Department of Neurosurgery , The Affiliated Xuzhou Hospital of Medical College of Southeast University , Xuzhou , Jiangsu , China.
authors.forename: Fei
authors.initials: F
authors.lastname: Sun
authors.affiliation: b Department of Neurosurgery , The Affiliated Xuzhou Hospital of Medical College of Southeast University , Xuzhou , Jiangsu , China.
authors.forename: Zhenguo
authors.initials: Z
authors.lastname: Sun
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use*; D003131:Combined Modality Therapy; D003907:Dexamethasone / Q000627:therapeutic use*; D004322:Drainage; D005260:Female; D020200:Hematoma, Subdural, Chronic / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D012189:Retrospective Studies; D012307:Risk Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D014207:Trephining / Q000379:methods*
chemical_list: D000893:Anti-Inflammatory Agents; D003907:Dexamethasone
keywords: Chronic subdural hematoma; dexamethasone; recurrence; risk factors